A design of a transportation system for the logistics at location South at FloraHolland Aalsmeer

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Delft University of Technology

FACULTY OF MECHANICAL,

MARITIME AND MATERIALS

ENGINEERING

Department of Marine and Transport Technology Mekelweg 2 2628 CD Delft the Netherlands Phone +31 (0)15-2782889 Fax +31 (0)15-2781397 www.mtt.tudelft.nl

Specialization: Transport Engineering and Logistics Report number: 2015.TEL.7921

Title: A design of a transportation system for the logistics at location South at FloraHolland Aalsmeer

Author: J.L.M. Osterholt

Title (in Dutch): Het ontwerp van een transport systeem voor de logistiek op zuid bij FloraHolland Aalsmeer.

Assignment: Master’s thesis

Confidential: yes (until 3,3,2016) Initiator (TUDelft): prof. dr. ir. G. Lodewijks Initiator (FloraHolland): N. Jansen in de Wal Supervisor (TUDelft): dr. ir. H.P.M. Veeke

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ENGINEERING

Department of Marine and Transport Technology Mekelweg 2 2628 CD Delft the Netherlands Phone +31 (0)15-2782889 Fax +31 (0)15-2781397 www.mtt.tudelft.nl

Student: J.L.M. Osterholt Assignment type: Master Thesis

Supervisor (TUD): Dr. ir. H.P.M. Veeke Credit points (EC): 35 Supervisor (Company): D. De Groot Specialization: TEL

Professor Prof. Dr. ir. G. Lodewijks Report number: 2015.TEL.7921 Confidential: until: 2016,3,3

Subject: A design of a transportation system for the logistics at location South at FloraHolland Aalsmeer

Introduction

On a yearly basis 7.700 growers bring 3.8 million trollies with flowers or plants to FloraHolland. Each morning the stored products are distributed and transported to the customers, who either bought or rented a space in the buildings of FloraHolland. There are two different type of flows at FloraHolland, the one that is already sold when the products leave the grower and the one that has to be auctioned at the flower auction. Each morning the sold products enter the distribution area and FloraHolland has 2,5 hours to deliver the products to the customer. The customers at location South at Aalsmeer are connected to the distribution area with the Aalsmeer Shuttle or Elektro HangBaan (EHB). The trollies are put into the system at location center and are automatically transported by this system towards the customers location where trollies exit the system.

Problem definition

Over the years the maintenance cost of the EHB have been increasing and an investigation showed that there are large necessary investments required to keep the system running. Besides the cost, the amount of transported trollies is uncertain. The general trend of the amount of handled trollies at FloraHolland is decreasing each year. These two developments combined resulted in the desired to start a research to develop a system, that has to be able to transport all of the different flows, has

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ENGINEERING

Department of Marine and Transport Technology Mekelweg 2 2628 CD Delft the Netherlands Phone +31 (0)15-2782889 Fax +31 (0)15-2781397 www.mtt.tudelft.nl Research goal

Design a system to transport all logistic flows at location South at FloraHolland Aalsmeer, considering the cost, throughput time requirements, and integration on both FloraHolland as the customers processes.

Research structure

 The logistic flows towards, from, and at South are analyzed with the Delft Systems Approach.  The processes at distribution and at the customers at South are analyzed with the Delft

Systems Approach.

 The functional requirements of the system are defined.

 A transport system is selected using Saaty’s multiple criteria analysis.  The concept is simulated using Discrete Process Simulation.

 A design of the required changes on the infrastructure is developed.  Relevant literature is analyzed.

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Summary

 1 or 2 pages.

 Should follow the structure of the report.  As a guideline:

o 1/3 introduction

o 1/3 intermediate chapters o 1/3 conclusions

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List of abbreviations

RB - Remote Buying

EHB - Elektro HangBaan or Aalsmeer shuttle

STW - Auction Trolley (in Dutch Stapelwagen)

DC - Danish Contrainer

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1 Introduction

FloraHolland is the largest flower auction in the world and has been the home of the Dutch floriculture sector for years. Meanwhile the floriculture sector outside Europe has been growing ever since. FloraHolland offers its customers a gateway to international trade because of a solid logistics network and market places at six different locations, of which five of them are located in the Netherlands and one in Germany. The different products of all the 5000 growers can be delivered at the auctions 24 hours, 7 days per week. The products are then traded via the connect or clock auction. With the digitalization, virtualization, and internationalization trends in the floriculture sector, FloraHolland implemented the remote buying system which provides the florist the possibility to purchase their products from their own location anywhere in the world.

Since most of the deliveries at FloraHolland take place during the night, the majority of the products are stored in a cool storage room. Before the auction starts the trollies with Connect products are transported the florist’s location, through the auction’s infrastructure. When the auction starts the rest of the trollies are transported from the cold storage to the auction room and are sold at one of the 38 auction clocks. The trollies are then transported to the distribution section of the auction. Here employees distribute the products in a process comparable to a reversed order picking process. When the trolley is either filled or has reached its change time, it’s transported to the florist, which in Aalsmeer is done partially by an automated system. The volumes handled by FloraHolland are changing and the cost of this automated system are rising. This research focuses on the design of an alternative for the existing system as state in the research goal:

“Design a system to transport all logistic flows at location South at FloraHolland Aalsmeer,

considering the cost, throughput time requirements, and integration on both FloraHolland and the traders processes.”

The system at FloraHolland Aalsmeer is described in chapter ‎2. This chapter describes the developments at FloraHolland and explains the processes that take place in the company. Chapter ‎3 uses the Delft System Approach to analyze the problem and defines the system borders and describes the different flows through the system. Chapter ‎4 summarizes the analysis and shows the research goal. Chapter ‎5 gives the analysis done to the selection of the designed transport concept, which is analyzed in detail in chapter ‎6. The implications of this design and the proposed infrastructural changes are elaborated in chapter ‎7. Chapter ‎8 concludes the findings and gives

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2 System description

This chapter first describes the system at FloraHolland Aalsmeer, the developments at FloraHolland Aalsmeer, the change in organizational structure, the different actors at the auction. Secondly it describes the processes and flows at FloraHolland Aalsmeer, starting with the supply, followed by the distribution, delivery and traders processes, and finally the return flows.

2.1 FloraHolland Aalsmeer

With around 25% of the annual clock turnover and around 50% of the remote buying turnover, FloraHolland Aalsmeer is the largest flower auction of the Netherlands. This turnover is achieved by 14 clocks and 3 auction rooms at Aalsmeer and in total more than 3.8 million trollies and Danish containers are handled on a yearly basis (FloraHolland, 2012). Besides the actual work the facility at Aalsmeer is open for public visits and therefore a lot of tourists take a quick peak at the famous Dutch flower handling skills. The structures within the redline in Figure 1 show both the 1.3 million square meters of the flower auction and the 240 thousand square meters owned by traders/customers. Within the center facility the supply area, clocks, auction rooms, both distribution of flowers and plants, and a number of traders/ customers are located. The two facilities connected to the central facility are the company Waterdrinker and facility South. In contrast to Waterdrinker, facility South facilitates an in-house infrastructure and automated system which delivers the trollies to a large number of different customers, traders, shipping agents, and brokers.

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2.1.1 Developments at FloraHolland Aalsmeer

Last couple of years have been challenging for a lot of Dutch companies and also for FloraHolland. The fact that the turnover grew in this year testifies to the power of the cooperation. But while the volume of houseplants grew with 1,1%, the volumes of both cut flowers and garden plants decreased with 0,9% and 3,2%. The increase in turnover is due to the increases in average price per product. Besides the change in volume there is also a shift from auction clock to direct sales, where the auction clock decreased with 4,7% the direct sales increased with 9,3% (FloraHolland, 2014).

This decrease in volume is expected to continue coming years because growers are focusing more and more on the customer and the customer-of-the-customer. The main reason is both growers and traders are scaling their production and this results in a larger volume and it becomes economically feasible to transport the products directly to the trader from the grower. Besides the change in volume, the production outside of Europe has been growing rapidly. So the globalization, digitalization, and virtualization of the international world economy is also seen in the floriculture and horticulture industry. These changes require a different service from FloraHolland because current services become outdated. Although the current turnover shows a small growth, this prospect is a bit optimistic since the physical flows to the auction clocks have decreased with six to seven percent. This reduction in flow requires a redistribution of the available resources and flexibilization of the current processes and systems (FloraHolland, 2013).

2.1.2 Change in organizational structure

FloraHolland Aalsmeer has gone through a large change last year. To be able to provide a higher service level and a better organizational connection with the members of FloraHolland Aalsmeer is split in two departments; product and service. This change resulted in a reduction of 25% of management functions, a loss of 200 full time jobs and new members of the board of directors to facilitate the organizational change. These kind of changes challenge companies to be able to keep the normal activities from harm and try to rebuild and improve the results of the company.

2.1.3 Different actors at Aalsmeer

In order to get a good understanding of the situation at FloraHolland the different actors need explaining. This section explains the relation between the growers, traders, remote buyers, shipping agents, commissionaires, Eisenmann, and the employees at FloraHolland.

Since FloraHolland is a cooperative service provider for the trade of flowers there are a lot of different actors whose demands differ. The main actors are the members of the corporation, i.e. the

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by a board of directors, who communicate with the executive board of FloraHolland. In total Aalsmeer has 4775 active suppliers who deliver products to the flower auction.

Of course on the other side of FloraHolland are the 715 traders, who buy the products from the growers. FloraHolland facilitates a link between the growers and traders on multiple fronts, namely the payment insurance, quality checks, buffer capacity, and distribution of the trollies on packaging level. Because of the competitive pressure on the supply chain, the relation with some of the traders has gotten more tense over the last couple of years. Traders tend to contact growers themselves and on the same time FloraHolland is enabling customers further on in the supply chain to purchase products at the auction thus getting around the traders. This relation does not apply for all traders, and some of them tend to use the FloraHolland initiatives such as remote buying to their advantage and transform into shipping agents. Because of the remote buying system, the remote buyers have also become an actor at FloraHolland. They purchase products with the license of traders, which results in a lot of single packaging purchases.

Besides the growers and traders there are also shipping agents located in the facilities of FloraHolland. The shipping agents transport the products from different locations to the auction’s facilities. This transport can come from multiple locations such as the grower, the airport, or an FloraHolland auction and products are also transported to multiple locations such as the customer, the airport, or another FloraHolland auction. Some of the shipping agents have their own facility at FloraHolland and unload the truck at their own dock and distribute the trollies through the infrastructure of FloraHolland.

Other actors located in the buildings at FloraHolland are the commissionaires. They buy products at the auction and provide traders the possibility to buy small amounts of a certain product. They also execute a little work on the products in order to deliver specialized products. For example a nonstandard length of a product. They are not that large in amount of products, but they transport a lot of single piece products through the infrastructure of FloraHolland.

The actor who does not actually buy products at the auction, but has a large influence on FloraHolland is Eisenmann. Eisenmann is the builder of the Aalsmeer Shuttle also called; the Elektro HangBaan (EHB), which has been operational for almost 12 years. During this operation time the relation between Eisenmann and FloraHolland has become more tense, because maintenance and operational cost grew, service lowered, and performance standards were not met. Currently effort is put into repairing the relation between Eisenmann and FloraHolland to reach a common goal; proper transport performance to location South. The last actors, with a big influence on FloraHolland are the employees of FloraHolland itself. FloraHolland is a large company with around 3900 employees.

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Besides the employees with a permanent contract, also a lot of temporary employees are hired each day.

2.2 Process description

Figure 2 shows the floriculture supply chain. The growers receives seeds from the breeders and grow them into the desired products. The growers then transport their products to FloraHolland where the products are auctioned, distributed, and delivered to FloraHolland’s customers; the traders. The traders processes range from creating bouquets, to not changing anything on the products and just ship the products to their customers; the retailers. The retailers finally sell the products to the end customer.

The processes and departments at FloraHolland are grouped into three main functions; supply, distribution, and delivery. These functions will be discussed shortly in the following section. Within the flow of trollies three main distinctions can be made in the type of flow, namely:

1. Connect vs. Clock (13%-83%); Connect products are bought before they enter FloraHolland’s premises. The clock products still need to pass the auction clocks, either virtual or physical. The remaining 4% is a third party flow, which is similar to the connect flow, but handled different then the connect flow.

2. Flowers vs. Plants (61%-39%); Flowers are cut from their roots and are transported in a layer

of water, therefore they have a much shorter lifetime and are kept at low temperatures as much as possible. Plants are still attached to their roots and transported in a small amount of soil to keep them alive.

3. Auction trolley vs. Danish Container (92% - 8%) (at plants: 79%-21%); The difference between

the auction trolley (or in Dutch stapelwagen, STW) and the Danish container are the dimensions and handling during transport. On Danish Containers only plants are transported

Retailer

Breeder Customer

Supply Distribute Deliver Grower FloraHolland Trader

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These three distinctions all have influence on the required service to be provided in the three main functions at FloraHolland which will be discussed next. The total amounts of the three distinctions flowing through FloraHolland are summarized in Table 1.

2.2.1 Supply

The supply of trollies at FloraHolland is a 24 hours, 7 days per week process, this is the unique service FloraHolland provides to enable the growers the possibility to always deliver and the traders to get their products early in the morning. The trucks arrive at docks where the products are unloaded and enter the FloraHolland system. The effect of the first distinction between plants and flowers is straightforward at the supply process: flowers always have to be transported to the cold storage rooms, and plants need to be transported to their buffer near the chain belt. The second distinction, connect vs. clock has the following effect; when the connect products arrive they either get buffered in a cold storage room or if they are requested at that time they get transferred into the distribution process. The connect flow usually starts at 5 am, before the auction clock flow starts, so that the auction process does not get slowed down by the connect products. The clock products are stored in either the cold or normal storage areas, depending whether it concerns are plants or flowers. The third distinction has little effect on the flower area, since there are only STWs, but at the plants area both DCs and STWs are used to transport the products. The presence of both types of trollies requires some extra dedicated DC forklifts and some extra handling steps where the DCs are turned 90 degrees to be put onto the chain belt. The supply docks at the center location can in Figure 3.

Table 1: Numbers (x1000) of yearly physical transactions at FloraHolland Aalsmeer to South

Connect Clock STW DC Total

Flowers 115 1.825 1.940 - 1.940

Plants 309 672 981 250 1.231

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2.2.2 Distribution

The main functions at distribution are the same at both the plant and flower floor. The connect flow to location South gets put into the EHB and the connect flow to North and East are transported there by tractor. The clock flow has to enter the distribution process and also gets transported to their trader by either the EHB or tractor. However, between flowers and plants there are two main differences. First, all of the plants physically pass through the auction room and at the flowers pass the clock either virtual or physical. Second, the flowers get distributed by the “voice” system and the plants are distributed by printed lists. The distribution process can be compared with a reversed order picking process. For example, in the supermarket the customer walks around the store and picks desired products from the shelf and transports them through the store and finally walks up to the counter, pays, leaves the store, and returns the empty trolley. At distribution, an employee starts with a filled trolley and has to drive by all of stations on his schedule to deliver a number of crates with flowers. First the flower process will be explained, later on the plant process will be explained. At the flowers floor the trollies (only STWs) are transported from the cold storage by chain belt, then they either pass the auction room and flow into a buffer or directly flow into a buffer. This buffer contains multiple rows where employees grab a trolley and enter the main lane to all the paths, shown in Figure 6. Then the employee starts distributing the products on his trolley on the STWs located along multiple paths based on the commands the “voice” system gives him/her. When the employee reaches his/hers destination he has to tell voice the control number located at the floor. If this matches the required destinations voice registers the input and tells the next destination. After the distributing has been done, the controllers will take out the filled trollies and connect the loaded products to the trolley and checks whether the amount of crates put onto the trolley matches the order. Based on either the changing time or filling percentage of the trolley, the controller passes on

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with a tractor or directly puts the trolley into the EHB. The floor plan of the distribution area can be seen in Figure 7.

At the plants floor the main process is the same, but voice is not yet implemented at this area. The employees are given lists with locations and numbers of plants. They drive to the various locations and distribute the plant along the different paths. The disadvantage of this approach is the lack of control and error sensitivity of the process. If plants are put onto the wrong trolley another employee needs to transport them back to their correct location when he checks and controls the trolley. If the trolley passes the check it gets put into a train. Another process controller keeps track of the trains and orders employees to transport them to the shuttle or trader. The floor plan of the distribution area can be seen in Figure 8.

One of the challenging demands on the distribution system is the changing amount of trollies. Figure 4 shows the difference of trollies between every day, and Figure 5 shows the change per hour on an average day at the Aalsmeer facility. The pattern in Figure 5 seen in this year is representative for throughout the year. Besides these average days, there are also a number of days with a high demand such as Dutch mother’s day, Valentine’s day, international women’s day, etc.

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Figure 5: Daily average number of transports to South in 2013

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Figure 7: Floor plan distribution flowers

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2.2.3 Delivery

The delivery to the traders happens in two ways, by train or by the Aalsmeer shuttle. The delivery by train is a straightforward process where a train driver picks up the buffered train and delivers it at one or more locations based on an order sheet. The Aalsmeer Shuttle is the only an automated unique flower transport system in the world. Each morning at 4:00 am the Aalsmeer Shuttle is started and every day at 5:00 pm the system is shutdown. The trollies can be loaded into the shuttle in a random order and the system scans the trolley and retrieves its location based on the scan done by the controller at distribution. If the location is unknown or something is sticking out of the trolley the system will reject the trolley and an employee is notified that something is wrong. If a trolley passes the tests it is lifted up into the system and transported to the trader as can be seen in Figure 9.

The Aalsmeer Shuttle was one of the prestige projects at the Aalsmeer Auction before the fusion into FloraHolland. At the time the shuttle was built, a similar project was started at the flower auction in Naaldwijk. Aalsmeer wanted to be the most advanced flower auction in the world, but in contrast to Aalsmeer, the plug was pulled out of the project in Naaldwijk although most of the construction had been done. It is unclear why Aalsmeer still built the Aalsmeer Shuttle and Naaldwijk thought such a system was too expensive. This is still a delicate situation between the nowadays colleagues. At Aalsmeer employees still think Naaldwijk cannot deliver on time and at Naaldwijk they think that the Aalsmeer Shuttle is way too expensive.

2.2.4 Traders process

At FloraHolland Aalsmeer there is a certain number of traders, commissionaires, and shipping agents.

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supply by train. The traders at location South structured their processes around the shuttle exits. Figure 12 shows two different companies, OZ Export and D. Visser & Sons. OZ Export is one of the larger traders with over 1,3 million trollies per year in contrast to D. Visser & Sons who handles just over 19 thousand on a yearly basis. OZ Export has two shuttle exits for themselves and D. Visser & Sons has to share a shuttle exit with their neighbor. This difference in size is seen in all the following processes; where OZ Export has a large system consisting of a large cold storage room, conveyor belts, a shoe sorter, and over 200 employees. D. Visser & Sons shares a cold storage room, employs just under 30 people and transport everything manually. These differences are just because of the difference in size. To emphasize the diversity in traders, the three largest traders containing over 30% of the total transports at South, differ a lot as well. OZ Export has built a large conveyor belt system with a large cold storage room in order to keep the products cold as long as possible. FleuraMetz has a relatively small cold storage room and also has built a conveyor system and tries to ship out the flower as soon as possible, and finally Hilverda de Boer has an even larger cold storage room starting where the shuttle enters their system as can be seen in Figure 11 and Figure 10. The difference in size of the cold storage area is a result of the strategic policy difference. FleuraMetz strives to ship all of the products as soon as possible and try not to store anything. Hilverda de Boer wants to be able to sell products whenever a customer needs it and therefore they have a large stock of products. OZ Export has the option to produce bouquets, so they have a whole production line set up.

The traders have a meeting with FloraHolland four times a year, where they discuss problems in order to keep FloraHolland updated about their wishes and requirements. The main analogy between all traders is they want to have a constant flow of arriving trollies, rather than fast delivery. The requirements expected from the traders will be discussed in more detail in chapter ‎3.

2.2.5 Return flows

Besides the flows of trollies that carry flowers and plants, there are return flows inside FloraHolland as well, which represent a significant claim on the infrastructure at FloraHolland. After the traders completed their processes, most of the products are not transported on auction trollies. Auction trollies are designed for the auction processes and are very robust and not as space efficient as other carriers. This results in a flow of empty trollies from the trader towards the auction. The handling of the empty trollies is a service that is provided by FloraHolland and happens either by using the Aalsmeer Shuttle or by tractor. The other return flows are packaging trollies, wrongfully delivered or rejected products, and waste trollies. These flows will be explained in chapter ‎3.

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Figure 10 Left: Arrival at FleuraMetz Right: Arrival at Hilverda de Boer

Figure 11 Left: Conveyor system at FleuraMetz Right: Conveyor system at OZ Export

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3 Process analysis

This chapter analyzes the system at hand. First the highest aggregation level will be explained followed by opening the black boxes. The handling of the products will be opened first. Secondly the trader processes will be analyzed. Then the different flows going through the system are explained, followed by the functional requirements. Concluding, the increasing cost of the current system will be explained.

In order to provide a structured analysis on the processes the system will be analyzed using the Delft System Approach (Veeke, Ottjes, & Lodewijks, 2008). The system as described can be presented as a black box with a transformation of the input flow to the output flow to some extent of the requirements reported by the performance information. Figure 14 represents the black box representation of the system. The main function of the system as a whole; is handling of the products. Growers deliver trollies to the system and the handling of the products ends when the traders deliver them to their customers. Since there are multiple actors involved the requirements of the system can be grouped per actor. The performance of the system is measured in terms of the Key Performance Indicators (KPI) and the annual report.

To be able to get a better understanding of the underlying processes the black box is opened. The handling of the products does not concern only FloraHolland, but also the other actors explained in the previous chapter. Therefore two transformations can be identified; the handling of FloraHolland and the handling by the buyers. Although both FloraHolland and the buyer handle the products, the requirements on the system come from different actors as can be seen in Figure 15.

Handle products

Requirements: - Grower - Buyer - Transporter - Eisenmann Performance: - KPI - Annual report

Arrived trollies Delivered trollies

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When opening the black boxes of FloraHolland and the buyer a distinction can be made on full trollies towards the trader and return trollies towards FloraHolland. First the flow to the trader will be explained then the return flows will be explained and finally the flow between traders will be explained.

3.1 Handling the products

This research is about the transport system towards the traders at location South so therefore the system scope starts at the distribution function at FloraHolland and ends when the trollies are received by the trader. When zooming in on Figure 15 the following functions in Figure 16 are found at the system. First trollies are received by FloraHolland, then distributed and delivered at the trader who receives, processes, and delivers the trollies at their traders. The agreement between the traders and the flower auction is that 95% of the trollies have to be delivered within 2,5 hours starting from the moment they are bought. The distribution process takes up 2 hours, which leaves the deliver part half an hour to deliver the trollies.

Opening the deliver black box reveals the functions as can be seen in Figure 17. All trollies that enter the deliver function are received by FloraHolland. Depending on the type of trolley a scan is made and the trollies is registered. Next the trolley is transported to the right location. The trollies that

Requirements: - Grower - Trader - Transporter - Eisenmann Performance: - KPI - Annual report Handle products

Arrived trollies Delivered trollies

Requirements: - Grower - (Remote) Buyer - Transporter - FloraHolland Performance: - KPI - Annual report

Handle products Delivered products

FloraHolland Trader

Figure 15: Black box representation of FloraHolland and the buyer

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have to go to a trader have the option to be buffered before they are delivered in the trader’s area. As said in the previous chapter there are lots of different flows at FloraHolland. The difference between these flows will be explained in paragraph ‎3.3.

3.2 Trader processes

At the trader the incoming trollies are scanned and besides the check to see if it is the right trolley a quality check is done. If the products are not the right quality the products are sent back to the flower auction. The returned products are passed on to a quality check to see whether the grower or the trader is right. The products that passed the check enter the traders processes. They are sorted and placed in buffers, waiting on transportation to the (cold) storage, where they are buffered again until the products are sold. After they are sold, some processing is done, varying from creating bouquets or placement in a different kind of packaging. After they are processed the products await transportation by truck.

Code Pass on and

scan trolly Transport to system System Scope Receive Transport to buyer Deliver at buyer Deliver Receive Delivered trollies (Full)

Return trollies _{Transport to}

location

Deliver at destination

Delivered trollies

Figure 17: Aggregation level 2

Scan

Transport to

(cold) storage Deliver

Sort Process Check Delivered trollies Received trollies Returned trollies

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3.3 Different flows

As said in chapter ‎2 there are multiple different flows going towards South and there are also multiple flows coming back from South. This section elaborates the difference in numbers and processes on each flow.

3.3.1 Connect

The distribution of connect is a process which happens each week day and is divided into two shifts; the night and day shift. The day shift takes place from 7 am until 5 pm and takes up 40% of the total connect volume. The whole day connect handling takes a maximum of one hour. In that hour 10 minutes is reserved for the receiving part of the process and there is 50 minutes of delivery reserved. The night shift has a slight different process since the time span is right before the auction process. All night trollies are buffered until 4 am when the distribution of trollies starts. Trollies are distributed on trader location in the complex and the trollies destined for South are buffered right in front of the EHB elevators. The South trollies are then put into the lift at 4:45am so that they will arrive just before the beginning of the auction process.

The connect flow of trollies is expected to continue to grow coming years. This is a result of traders buying directly from growers, but want to have the advantage of shared transportation and storage at FloraHolland. The development of the growth of the connect flow can be seen in Figure 19.

3.3.2 Clock

The clock process starts each day at 6am and has an end time which depends on the total number of to be auctioned trollies. At the flower floor there are two chain belts connecting the cold storage

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rooms to the auction area. As mentioned earlier, the auction process is changing, which will result in a 20% increase in auction speed. To copewith this change the throughput time agreement might be lengthened from 2,5 to 3,5 hours. Otherwise an increase of required buffer capacity or transportation speed is necessary and receiving speed of traders must be increased. But since the auction process will be finished earlier the required extra personnel can be used on different processes such as the delivery of trollies to the traders.

Expected is that the amount of clock trollies will decrease over the coming years, because the traders buy directly from the growers instead via auction clock. The only downside of buying directly of the grower is that the grower might have a lower price per product. If a buyer buys a full truckload at the grower, this is delivered directly to his company instead via the processes of FloraHolland. This is one of the reasons why the clock flow is expected to continue to decrease at FloraHolland. Allthough Figure 20 shows an increase of clock trollies towards South in 2014. However, this can be easily explained because the vancancies within South in 2013. A couple of companies went bankrupt at the end of 2012 and those spaces have been filled in 2014. Thus the increase seems promising, but is not expected to last.

3.3.3 Packaging

Another return flow is the flow of empty packaging. The flowers are transported in all sort of buckets and cardboard boxes. All of these containers have different sizes and a different deposit. If a trader’s has a trolley filled with packaging, they announce it to FloraHolland who sends an employee who

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3.3.4 Waste, rejected, and wrongfully delivered products

The rejected or wrongfully delivered products flow and the waste flow are really small in size and happen in the same matter as the empty trollies, they are announced to FloraHolland who send an employee to pick up the trollies, this always happens by tractor. The waste trollies is not available, but after interviewing some of the employees this flow is negligible. The same goes for the rejected and wrongfully delivered product flow, the amount of transported trollies is negligible compared to the full and empty flows at South.

3.3.5 Trader to trader

The infrastructure at FloraHolland is freely accessible to the traders. This results in a lot of trader to trader traffic. Traders trade have different reasons to trade with each other depending on their processes. For example, some change the size of the products which is required by others. Or if a trader requires a product that has already been auctioned, but still is in stock at another trader the product is traded between them. This flow is seen a lot in the hallways, but there is no data available. But in contrast to the waste flow this flow seems to be non-negligible. Therefore this flow has been counted only on an average day, because of a shortage of available employees. A summarization of the counting can be found in Appendix D: Trader to trader measurement. During the counting a couple of strange things were noticed. Although it is prohibited to transport Danish Containers by using their own wheels, almost none of the registered transports where done by using carriers. This flow is always done by employees of the traders. When a transport is needed one of the employees who has time on his hand is assigned to deliver or pick up the products. In 2014 a company, Tjoek-Tjoek, saw potential in a service which made the delivery of this flow easier for the traders. This competitor uses the infrastructure at FloraHolland and picks up and delivers products spread out through the whole facility.

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3.3.6 Empty

As said in chapter ‎2, there is also a large volume of empty trollies going back from the traders to FloraHolland. If the trader has an empty trolley during the morning period, when it still is prohibited to enter the EHB, the trader forms a train and puts it into the hallway. The reason why it is prohibited to transport empty trollies back to the center facility is the impact on the Aalsmeer Shuttle. Experience showed that the capacity of the system reduced drastically, because the Aalsmeer shuttle carriers had to travel to the empty output instead of directly to the shuttles input. Most of the enter trollies enter FloraHolland’s system in the afternoon and a large part of them has to be transported back during the night, when the Aalsmeer Shuttle has been shut down. Figure 23 show the periodical development of the trollies over the last three years.

Figure 22: Trader to trader flow, measured on 5-August 2014

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3.3.7 Summary of the different flows

To understand the impact of the flows not only the development over the years, but a combined impact on the system must be identified. To make a more detailed analysis on the impact of the flows it is decided in a dialogue with the Manager of Delivery at FloraHolland that the 2013 data was sufficient for this research. Figure 25 shows the distribution of days sorted on number of transports through the Aalsmeer Shuttle, so the sum of connect, clock, and empty trollies. Figure 26 shows the distribution of days sorted on the maximum hour peak during the day. This peak is the peak of the total trollies in the Aalsmeer shuttle, so also the connect, clock, and empty trollies combined.

The requirement of delivery within half an hour has a great influence on the peak capacity of the system. The Aalsmeer Shuttle is said to correct the delay created at the distribution process. This problem is well known and there is a constant improvement on the throughput times. Figure 24 shows the distribution of throughput times per trolley in Q2 of the clock flowers flow towards South. Table 2 shows the percentages of trollies that are delivered within 30 minutes in 2013 by the Aalsmeer shuttle.

Table 2: Percentage delivered within 30 minutes in 2013

Flowers Plants

Clock Connect Clock Connect

Q1 0,987 0,948 0,969 0,964

Q2 0,982 0,967 0,977 0,962

Q3 0,980 0,961 0,984 0,960

Q4 0,990 0,943 0,990 0,966

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Since all of the flows must be combined to get an understanding of what flows through the system at location South. Figure 27 shows all of the mentioned flows on an average day.

Of course all of these flows pass through the infrastructure at South, but it is necessary to know how much each buyer purchases. The amounts that each trader buys has a direct influence on the impact on the capacity required in each hallway. For example, the three largest traders (OZExport, FleuraMetz, and Hilverda de Boer) purchase almost 30% of the total volume that goes towards South annually. The daily average transports towards and from each trader by the Aalsmeer Shuttle are presented in Figure 28. These are only the clock, connect, and empty flow registered by the system. Other data on trader to customer is not available per trader, the same goes for the waste and packaging flow. Connect Clock Packaging Waste Customer to Customer Packaging Waste Customers’ trollies Empty Empty Scan Destination Deliver 850 910 960 5540 5500 7300 960 5500

Not registered Not registered

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3.4 Functional Requirements

Different requirements are requested of the system, because of all the different actors. By interviewing different parties a list of functional requirements was compiled. Appendix A: all of the requirements shows the summarization of the different requirements desired by the different parties. In order to select a concept these requirements were analyzed and summarized into 7 criteria:

1. At least current service level: The service level agreement is the minimum level of performance that has to be met in a concept.

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3. Reliability: The system needs to be robust and there is a certain level of redundancy required

within the design.

4. Cost compared to current system: The design does not necessarily need to be the cheapest

solution there is as long as the cost are less than the current system and has a return on investment of 5 years.

5. Flexibility: Flexibility means the way the system is able to be reutilized in a different process

at FloraHolland.

6. User friendliness: User friendliness means on both maintenance as operational aspects of the

design.

7. Controllability: The ease of control means, the amount of time is needed to direct the system

into tolerable performance on both operational as maintenance functioning.

3.5 Increasing cost of the current system

Besides the expected decrease in number of transports by the Aalsmeer Shuttle, the cost are expected to increase coming years as can be seen in Figure 29. This is a result of incorrect engineering of the system. The steel infrastructure has been calculated to withstand a static load, but since the trollies travel with 11 km/h and have to brake and turn a lot, the stresses are too high. This results in breaking bolts, which causes parts of the system to malfunction. An investigation is started to find out whether it is safe to continue the operation or large changes have to be made on the current Aalsmeer Shuttle. Besides the malfunctioning of the system, the contractual maintenance has been increasing over the last years. Eisenmann, the constructor of the system, has been increasing cost each year, and currently FloraHolland is investigating the causes of these increases. Because of the large investments that have to made each year to repair the current system, the repayments of the current system are continuing, which leads to a situation where the system has not been depreciated. In the coming years, all of the carriers of the system need a large refit, because of the life expectancy of the electric parts.

Besides the maintenance cost, there is not a clear insight in the operational costs such as labor, cleaning, damage due to incorrect use, or energy cost.

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C o st in m ill io n e ur o

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4 Research goal

The polarity between the Naaldwijk and Aalsmeer employees, can be described best by quotes such as:

“The EHB works just as an employee, on busy days it cannot handle volumes as it should be.” Or

“Luckily we have an EHB, because in Naaldwijk they are making a mess of their delivery process.” To make a final decision on whether to keep or to get rid of the Aalsmeer Shuttle research was needed into the current system. FloraHolland’s research into the Aalsmeer Shuttle is twofold; on the one hand there are the increasing cost of the current system, and on the other side there is the change in amount of annually handled trollies. This research focuses on a replacement system for the Aalsmeer Shuttle and doesn’t include a grasp on the increasing cost, reduction of the cost or causes of the cost, but takes the cost of the current system into account. The research also excludes a study on the future scenarios, but a change in volume must be taken into account in the design of the system. By investigating the processes of both FloraHolland and the traders the following basic functions of a desired system have been determined:

The desired system needs to be able to receive the trollies, which means that they need to be registered and picked up at the location where they are presented. After that it needs to be an option to buffer the trollies, when further on in the system it is required to slow down the trollies. When they no longer need to be buffered, the trollies need to be transported to the right location, which requires a sorting function. Upon arrival, it must be possible to buffer again. Both full and empty trollies need to have the option to wait until there is room at the deliver part of either the traders or FloraHolland’s processes. Besides these functions there are the functional requirements set by the commitments made by FloraHolland. Summarizing all these statements, this resulted in the following research goal:

“Design a system to transport all logistic flows at location South at FloraHolland Aalsmeer, considering the cost, throughput time requirements, and integration on both FloraHolland and the traders processes.”

Figure 30: Required functions of the system

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5 Concept selection

This chapter describes the steps taken to get to the final design concept. First the selected concepts are explained followed by the assignment of weight factors to the selection criteria. With these selection criteria the concepts have been ranked and a concept is selected.

5.1 Concepts

Using the different functions specified in the requirements, partial solutions are developed together with employees at FloraHolland. As can be seen in the morphological overview in Table 3. Combining these solutions resulted in the following concepts:

 Keeping the EHB  Train transport  AGV  Large transport  Conveyor belts  Chain belt  Truck transport

 Warehouse located in South with train transport

5.1.1 Keeping the EHB

In order to compare the different solutions to the existing one, concept 1 is the solution of not changing anything about the current system. This seems an easy solution, but the current system also has its flaws. The system consists of lifts at distribution to lift the trollies onto the tracks which transport the trollies to their location. The sorting function is done by a number of switches which are controlled by a central software system. The transport happens in a separate area where no humans are allowed during operation, but since most of the time the system is located on the first floor a lot of space is created for other activities. On both ends there is manual labor required to put the trollies in and to reclaim them from the lift stations. The return flow of empty trollies are picked up at the lift areas and transported from there to the empty trolley buffer. This system only transports flows from connect, clock, and returns empty trollies back to South. The other flows such as trader-trader, the packaging, and waste trollies have to be done by train transport.

5.1.2 Train transport

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driving towards their destination. This concept can be optimized by changing routes and the way of control on the system. The influences of these changes must be done in a later stadium of the research. Changes in control are for example the options of formatting the trains, the handling of the return flow, and the handling of trader to trader trollies. The trains formed at distribution can range from trader specific to only South. When the sorting is done per trader, the train driver can immediately drive to the destination and deliver the trollies and drive back. If the drivers have to only pick up a train destined for South, the trains have to be sorted again when they arrive on the other side of the bridge. The influences on deliver time versus labor cost must be researched in a later phase in the research.

5.1.3 AGV

This concept works almost the same as the train transport concept, but it uses AGVs instead of human controlled tractors. This concept can be optimized by using different control settings. For example the choice of driving with single trollies or driving with trains of trollies. But because there is a lot of human traffic within the buildings of FloraHolland, this systems requires a dedicated transport area where the AGVs are driving.

5.1.4 Large transport

In order to reduce the occupation of the road to South the transport can be done by a large vehicle on which multiple trains are loaded and transported to South. Also at this concept, the trollies can be hoisted into the air, when more capacity is needed on the roads located on the base level. When the vehicle arrives at South the trollies must be unloaded and the sorting must be done at South by tractors.

5.1.5 Conveyor belts

A complete other solution to the way of transport is the installation of conveyor belts. Transport by conveyor belt can be done on different levels ranging from trolley to single bucket or packaging, these two will be explained in concept ‎5.1.5.1 and ‎5.1.5.2. Since the roads behind the chain belt on the base level must be accessible by other traffic, the loading stations at distribution flowers must transport the packaging to the first floor.

5.1.5.1 Conveyor belts packaging level

Because there is a system in place which transports the products on packaging level to South, the return flow of empty trollies reduces drastically. The flow of products towards South is taken from the trolley and put on a conveyor directly after distribution, which transports it to South. A sorter can be installed on the current bridge shifting the flow into multiple flows towards the different hallways located in South. Within the hallways the conveyor must have an exit per trader or just as the EHB

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have a couple of traders sharing one exit based on their size. This systems has one large downside, namely the handling of 1-trader trollies and connect trollies. These trollies are already completely filled when entering distribution. So the whole trolley has to be unpacked and loaded onto the conveyor system, resulting in an increase in throughput time of those buckets or packages. The complexity of the system increases when all of the flows at South have to be transported by the conveyor system. When it is necessary to transport the trader to trader flow and return flow of packaging and waste there must also be a system in place to support these flows. If these flows have not to be transported by the conveyor system enough space must be left in the hallways to enable train transport.

5.1.5.2 Conveyor belts trolley level

This concept transports the trollies on a conveyor belt, but the products are kept on their trolley. This concept is comparable to the existing system, but does not have powered single carriers. Compared to the conveyor belt on packaging level, the disadvantage of the extra handling on 1-trader trollies and connect trollies is eliminated by putting trollies on a conveyor belt. The trollies are buffered on the distribution side the same way the current system works, and there has to be space constructed to buffer the trollies at the trader side. The advantage of eliminating the empty flow by transporting the products on packaging level, does not apply in this concept. This flow has be thought of in the detailed design stage.

5.1.6 Chain belt

The transport of trollies to South can be done by using a chain belt such as used to transport the trollies from the (cold) storage rooms to the auction clocks. This concept works on the same principle as the concept ‎5.1.5.2, but the trollies are transported using their own wheels.

5.1.7 “Warehouse” storage at South

This concept reduces the flow from center to South drastically, and reduces driving times. The concept stores products to be delivered at location South, at a (cold) storage at location South instead at location Center. Trucks arriving from either growers or the other auctions can dock at the warehouse and unload their products. Since the traders have a predictable purchasing trend, a base level of products can be stored in the warehouse. If there are more products requested at South than there are currently present at the warehouse there is still transport necessary from the center clocks. The connect flow can already be stored at South when it arrives at FloraHolland Aalsmeer.

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ordered the products are transported to a trolley destined for the trader and leave the warehouse a couple of minutes before the requested time resulting in a just in time on demand delivery.

5.1.8 Truck transport

Instead of transporting the trollies via the internal route the trollies are transported by truck. Because of the large amount of docks the trucks have enough space to dock, but it will be a large challenge to transport the flows towards in location South. But most of all, the trader to trader flow will be a challenge. This concept is mainly constructed to see if the ranking from the multiple criteria analysis result in the expected manner.

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5.2 Morphological overview

Tab le 3 : M o rp h o lo gi cal o ve rv ie w P ic k up B uf fe r Tr ans po rt S o rt B uf fe r De li ve r Con tr ol Di str ib ution Cus to m er Cus to m er Di str ib ution El ev ato r El ev ato r tr ains Trai n tra ins Lo ad ing s ta tion Lo ad ing s ta tion M anu al Pa te rno st er lift Pa te rno st er lift qu eu es AGV (tra in) que ue s Au to mated Cha in be lt Cha in be lt Sing le tro lle y AGV Se mi -aut omated Lo ad ing s ta tion Lo ad ing s ta tion Tru ck Slop e Slop e W are ho us e Con ve yo r be lt Cha in be lt Bulk tra ns po rt er R oll er co nve yo r

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5.3 Multi Criteria Analysis

Selecting a concept can be subjective and a difficult task when multiple parties are involved in the decision process. (Saaty, How to make a decision: The Analytic Hierarchy Process, 1990) offers a solution to create a more objective selection process. First weight factors are assigned to the different selection criteria mentioned in section ‎3.4, then the concepts are evaluated on all of the selection criteria, which will finally result in a selected concept for further investigation. To select the concept, three employees with different jobs have been interviewed to get a view on the different interests. The interviewees are:

 The manager of delivery; he has the overview of the whole delivery process. He is responsible for the overall delivery, costs, and contact with traders.

 Team manager of delivery; he has a lot of experience on operational processes. His main focus is keeping control on the daily performance of the system. He is used to the different problems faced every day and has a lot of contact with the traders on operational level.  Project Manager of Facility Management; he has experience on the counseling of the

construction different projects within FloraHolland.

5.3.1 Assignment of the weights

(Saaty, How to make a decision: The Analytic Hierarchy Process, 1990) states that by directly assigning a weight to a selection criteria, the discussion will be a more about the politics of persuasion and of wheeling and dealing. This is why he proposes to compare the criteria judging them ranging from equal to extreme, corresponding to the verbal judgments are the numerical judgments 1,3,..,9. The results of the interviews can be found in Appendix B: Weight factor assignment. The weights and consistency ratio are calculated by using the Random Index by (Saaty, The analytic hierarchy process, 1980) and (Bunruamkaew, 2012). After reviewing and consulting the interviewees to improve the consistency, the summary of the weights can be found in Table 4. What becomes clear, is the difficulty of consistent ranking the criteria.

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5.3.2 Sensitivity analysis

Because of the variation in consistency ratios and thus assigned weights, the weights are varied to find out the influence the of the weight factors on the ranking of the concepts. Table 5 shows the variation done in the sensitivity analysis. Each column shows the different assigned weight factors, corresponding to the columns in Table 6.

5.3.3 Ranking the concepts

(Saaty, 1990) stated that people such as chess experts can deal with information involving simultaneously only a few facts. With more, they become confused and cannot handle the information. This is in combination with the difficulty to rank the weight factors, the ranking of the concepts on the selection criteria has been chosen on a scale from 1 to 10, 1 being the lowest score and 10 being the highest. The score per concept is average of the three interviewees and then

Table 4: Assigned weights to the criteria

Manager Team

Manager

Project manager

Average

at least current service level 0,17 0,24 0,05 0,15

Scalability 0,06 0,06 0,02 0,05

Reliability 0,13 0,15 0,13 0,13

Cost compared to current system 0,34 0,36 0,23 0,31

Flexibility 0,04 0,11 0,02 0,06

User friendliness 0,15 0,01 0,48 0,22

Controllability 0,10 0,07 0,08 0,08

Consistency Ratio 0,15 0,6 0,33 -

Table 5: Variation on the weight factors

1 2 3 4 5

at least current service level 0,15 0,20 0,10 0,10 0,14

Scalability 0,05 0,05 0,05 0,10 0,14

Reliability 0,13 0,13 0,13 0,13 0,14

Cost compared to current system 0,31 0,26 0,36 0,26 0,14

Flexibility 0,06 0,06 0,06 0,06 0,14

User friendliness 0,22 0,22 0,22 0,27 0,14

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5.3.4 Selected concept

During the interviews it seemed that the train transport concept was preferred by all different parties. This is also concluded by the multiple criteria analysis. Although it scores just a bit better than the current system the EHB it has some advantages and some challenges to be investigated. The strength of the concept lies with the ease on scalability, flexibility, and particularly the reduction in cost compared to the current system. The challenge of this system lies within reaching the service level. It was emphasized by the employees on the operational side of FloraHolland, that changing to train transport must include involving all of the traders in the process.

Table 6: Rankings assigned to the concepts with different weight factors

1 2 3 4 5

Keeping the EHB 6,2 6,4 6,0 6,1 5,8

Only train transport 6,6 6,4 6,6 6,6 6,4

AGV 5,0 4,6 4,7 4,7 5,0

Large transport 3,8 3,8 4,0 4,0 4,0

Conveyor belts packaging level 5,3 5,4 5,3 5,3 5,0

Conveyor belts trolley level 4,9 4,8 4,9 4,9 4,7

Chain belt 4,0 4,1 4,3 4,3 3,8

Roller conveyor 3,6 3,7 3,8 3,8 3,6

“Warehouse” storage at South 5,7 5,5 5,3 5,3 6,0

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6 Modelling of tractor transport

This chapter sets forth the arguments to simulate the proposed concept and then explains the simulation goals the selected input data. After that the description of the processes in the simulation are explained followed by the output. Then the verification and validation are explained and finally the conclusion of the simulation is explained.

6.1 Deterministic model

By using simplified calculations an insight can be given into the cost of the concept. The average speed of the tractors has been measured, with fully loaded train and with a fully empty train. Using the data provided by the Aalsmeer Shuttle and using floor plans, an average distance per trolley has been determined. Together with the flow of trollies per hour towards South an estimated amount of tractors can be calculated using the following formulas:

𝑎𝑚𝑜𝑢𝑛𝑡 𝑜𝑓 𝑡𝑟𝑎𝑐𝑡𝑜𝑟𝑠 =𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑡𝑟𝑎𝑖𝑛𝑠 / ℎ𝑜𝑢𝑟 𝑐𝑦𝑐𝑙𝑒𝑠/ ℎ𝑜𝑢𝑟 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑡𝑟𝑎𝑖𝑛𝑠 / ℎ𝑜𝑢𝑟 = 𝑡𝑟𝑜𝑙𝑙𝑖𝑒𝑠 / ℎ𝑜𝑢𝑟 𝑡𝑟𝑎𝑖𝑛 𝑙𝑒𝑛𝑔𝑡ℎ 𝑐𝑦𝑐𝑙𝑒𝑠/ℎ𝑜𝑢𝑟 𝑝𝑒𝑟 𝑡𝑟𝑜𝑙𝑙𝑒𝑦 = 𝑎𝑣𝑒𝑟𝑎𝑔𝑒 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑡𝑟𝑜𝑙𝑙𝑒𝑦 𝑎𝑣𝑒𝑟𝑎𝑔𝑒 𝑠𝑝𝑒𝑒𝑑

By using the cost estimates provided by FloraHolland, the result can be seen in Table 7. Because of the difference in flows both the cost of the maximum peak and average peak have been evaluated. This estimations shows a promising result. Therefore it is necessary to do a detailed study on the required amount of tractors and the impact on the current infrastructure at FloraHolland. This analysis will be explained in the following chapters.

The assumptions made in order to calculate the annual cost are:  Personnel cost: € 40.000 / year

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6.2 Simulation goal

The deterministic model showed a promising result on the required amount of tractors to deliver the trollies, but this model is simplified in such a way that it is required to investigate the influence of the simplifications. This is done by a Discrete Process Simulation, which is made by using Delphi TOMAS by (Veeke & Ottjes).

The goal of the simulation is to determine:

 The required amount of tractors in order to deliver 95% of the trollies within 30 minutes.  The occupancy of the tractors during the day.

 The required capacities of the hallways.  The required capacities of the intersections.

To investigate the first two goals, the amount of tractors is varied. When the throughput time requirement is met, the output data is used to calculate the required capacity in the intersections and hallways.

6.3 Input data

As input to simulate the system data from Aalsmeer Shuttle is used. The trolley’s arrival time, arrival station, and destination are registered as soon as they are enter the Aalsmeer Shuttle, which can be seen in the example in Figure 31.

Table 7: Estimated cost of tractor transport

Maximum Average number of trains 42 30 Demolition cost € 975.000 € 975.000 Depreciation cost € 69.738 € 50.099 Maintenance cost € 41.843 € 30.059 Operational cost € 1.673.714 € 1.202.366 Investment € 1.046.071 € 751.479

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Because of the uncertainty of the future volumes three days have been selected in consultation with the manager of delivery at FloraHolland. Table 8 shows the three days;

 the 8th of April, the day with the maximum half hour peak.  the 21st of May, the day with the maximum amount of trollies.

 the 4th of June, an average day comparable with the day the trader-to-trader flow was measured.

The fourth day run in the simulation is the average day combined with the measured data on trader-to-trader trollies. So the flows put into the simulation model are the full, empty, and trader-trader-to-trader trollies. The waste and packaging are left out because these flows have no throughput time constraint. Although the empty trollies also do not have a time constraint, the impact of this flow on the infrastructure is too large to disregard during auction time.

The distribution of the arrival of trollies during the day are shown in Figure 33, Figure 34, Figure 35, and Figure 32.

Table 8: Selected input days

Maximum peak Maximum volume Average 8th -April 21st May 4th June

Total to South 8822 11088 6783 from South 6542 7835 5817 Half-hour peak to South 928 882 725 from South 520 635 567

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Figure 35: Maximum volume day input Figure 34: Maximum half hour day input

A design of a transportation system for the logistics at location South at FloraHolland Aalsmeer

Summary

List of abbreviations

Table of contents

1 Introduction

2 System description

2.1 FloraHolland Aalsmeer

2.2 Process description

3 Process analysis

Handle products

3.1 Handling the products

3.2 Trader processes

3.3 Different flows

3.4 Functional Requirements

3.5 Increasing cost of the current system

4 Research goal

5 Concept selection

5.1 Concepts

5.2 Morphological overview

5.3 Multi Criteria Analysis

6 Modelling of tractor transport

6.1 Deterministic model

6.2 Simulation goal

6.3 Input data