Order picking is considered one of the most time-consuming operations in picker-to-parts warehouses. Accordingly, more emphasis has been given to the task of improving the efficiency of order picking systems in general, and the required traveled distance during the order picking operation, specifically. In this thesis, we focus on two main factors that significantly affect the efficiency of order picking systems: the assignment storage policies, including the full-turnover, nearest-location and random storage policies; and the warehouse layout structure, in terms of the depth and the number of storage aisles. We investigate the combined effects of these two factors on the order picking travel distance. While previous research compares the full-turnover to the random storage policy, we compare the performance of the full-turnover policy to the nearest-location and random storage policies over various warehouse layout alternatives. For this purpose, we present a methodology for estimating order picking travel distance in a single-block, open-ended warehouse, under the assumptions of S-shape routing and discrete order policies.

Thesis (MSc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Order picking is the most important activity in distribution centres. It involves the process of retrieving products from storage in response to a speci c customer request. The order picking system in a distribution centre used by Pep Stores Ltd. (Pep), located in Durban, South Africa, is considered. The order picking system in Pep utilises picking lines. The system requires that the pickers move in a clockwise direction around the picking line. The planning of picking lines may be divided into three tiers of decisions. The rst tier determines which Stock Keeping Units (SKUs) should be allocated to which picking line and is known as the SKU to Picking Line Assignment Problem (SPLAP). The second tier, the SKU Location Problem (SLP), considers the positioning of the various SKUs in a picking line. The nal tier considers the sequencing of the orders for pickers within a picking line and is referred to as the Order Sequencing Problem (OSP). Collectively, these three tiers aim to achieve the objective of picking all the SKUs for all the orders in the shortest possible time. The decisions associated with each tier are made sequentially during the planning of a picking line. Each problem therefore relies on the information generated by its predecessing tier(s). Initially the OSP is addressed. A number of heuristic and metaheuristic approaches are presented, together with an exact formulation to solve this tier. The size of the problem is reduced by using a relaxation of the problem that may be solved exactly. A number of greedy tour construction heuristics, a scope and ranking algorithm, methods based on awarding starting locations with respect to preference ratios and a modi ed assignment approach was used to solve the OSP. Furthermore, a tabu search, simulated annealing, genetic algorithm and a generalised extremal optimisation approach are used to solve the OSP. The solution quality and computational times of all the approaches are compared for the data provided by Pep, with the generalised extremal optimisation approach delivering the best solution quality. Two methods from the literature was used to model the SLP, whereafter an ant colony system was used to maximise the number of orders in common between adjacent SKUs. A number of agglomerative clustering algorithms were used from which dendrograms could be constructed. Two novel heuristic clustering algorithms were considered. The rst heuristic calculates a distance between two clusters as the set of orders that have to collect all the SKUs in both clusters, whereas the second method is based upon the frequency of SKUs within a cluster. Little or no improvement was achieved in most cases. The SPLAP was introduced by means of a number of possibilities of how to formulate objectives. A possible exact formulation is presented, followed by a nearest neighbour search, which was initially used to construct new picking lines based on all data sets. A di erent approach was then taken by means of a tabu search where the waves of two or three picking lines were altered. Signi cant savings may be incurred for large data sets. / AFRIKAANSE OPSOMMING: Die opmaak van bestellings is die belangrikste aktiwiteit in 'n distribusiesentrum. Dit behels dat geskikte hoeveelhede produkte uit stoorplekke opgespoor en herpak moet word om aan kleinhandeltakke gestuur te word. Die bedrywighede binne een van Pep Stores Ltd. (Pep) se distribusiesentrums in Durban, Suid-Afrika, word beskou. Die sisteem vereis dat die werkers in 'n kloksgewyse rigting om 'n uitsoeklyn beweeg. Die beplanning van die uitsoeklyne kan verdeel word in drie besluite/probleme. Die eerste besluit is watter voorraadeenhede (VEs) toegewys moet word aan watter uitsoeklyn. Die tweede besluit is in watter vakkies in die uitsoeklyn die VEs geplaas moet word, en word die VE-plasings probleem (VLP) genoem. Die nale besluit is in watter volgorde bestellings opgemaak moet word in 'n uitsoeklyn, en staan bekend as die volgorde-van-bestellings-probleem (VBP). Die doel van al drie hierdie probleme is om al die bestellings in 'n uitsoeklyn in die kortste moontlike tyd af te handel. Die besluite wat verband hou met elke vlak van besluit word opeenvolgend gedoen tydens die beplanning van 'n uitsoeklyn. Die oplossing van elke subprobleem berus op die inligting van die voorafgaande probleme. Aanvanlik word die VBP beskou. 'n Aantal heuristiese en metaheuristiese benaderings word aangebied saam met 'n eksakte formulering om die derde vlak op te los. Die grootte van die probleem is verminder deur die gebruik van 'n verslapping van 'n eksakte formulering. 'n Aantal toerkonstruksie heuristieke, 'n omvang en rangorde algoritme, metodes wat gebaseer is op die toekenning van beginpunte met betrekking tot voorkeurverhoudings en 'n veralgemeende toewysingsprobleem is gebruik om die VBP op te los. 'n Tabu-soektog, gesimuleerde tempering, genetiese algoritme en 'n veralgemeende-ekstreme-optimering-benadering word ook gebruik om die VBP op te los. Die oplossingsgehalte en berekeningstye van al die benaderings word vergelyk vir werklike data wat verskaf is deur Pep. Die veralgemeende-ekstreme-optimering-benadering lewer die beste oplossingsgehalte. Twee metodes uit die literatuur is gebruik om die VLP te modelleer, waarna 'n mier kolonie stelsel gebruik word om die aantal bestellings wat aangrensende VEs in gemeen het te maksimeer. 'n Aantal groeperingsalgoritmes word gebruik wat dendrogramme kan lewer. Twee heuristiese groeperingsalgoritmes word oorweeg. Die eerste heuristiek bereken die afstand tussen twee groepe as die aantal bestellings wat al die VEs in beide groepe moet versamel, terwyl die tweede metode gebaseer is op die frekwensie van VEs binne 'n groep. Min of geen verbeterings is in die meeste gevalle gevind. Die eerste besluit word bekend gestel na aanleiding van 'n aantal moontlike maniere om die doelwitte te formuleer. 'n Moontlike eksakte formulering word aangebied. 'n Alternatiewe benadering is geneem deur middel van 'n tabu-soektog waar die golwe van twee of drie uitsoeklyne gewysig word. Beduidende besparings word gerealiseer vir groot datastelle.

Due to growing population over the past decades, settlements are scattered in sparse as well as dense clusters across Dalarna County. However, irrespective of any physical, social or economic conditions, free public health care must be available at a minimum and equal distance of travel for all citizens of a region. In the current scenario in Dalarna, around 16% of the population travels beyond 10 km to reach their nearest medical facility. The aim of this study is to suggest the most favorable locations for Mobile Hospital services across Dalarna County, based on spatial analysis of accessibility, population coverage, and importantly, in a way that travel distance, is minimized and equal for all. This study makes use of Multi Criteria Analysis methods. The problem of mobile hospital site selection is broken down into criteria, and Analytic Hierarchical Process is used to evaluate weights for each criterion. Then, a weighted overlay results in regions with score-based suitability for a mobile hospital. Maximum population coverage based Location Allocation analysis results in generating a proposed Facility and Demand Coverage output. The results show an increase in coverage of population, while meeting the requirements of criteria in the aim.

Syftet med fallstudien var att undersöka vad Airshoppen Travel Retail kan tänka på viddesignen av sin nya lagerlayout. För att genomföra studien har en teoretisk modell tagits fram som fokuserar på hur företags layout kan designas. Med den teoretiska modellen analyseras först två verksamheters lagerlayout. I nästa steg användes analysen för att vidare analysera och ge rekommendationer till Airshoppen Travel Retail angående vad företaget kan tänka på vid designen av sin nya lagerlayout. Genomförda intervjuer och observationer visade att utvecklingen av lagerverksamheternas processer anpassades till, och begränsades av, platsbristen. Tidigare forskning talade för att designen av ett lager ska grundas i valet av system. Bristfällig design kan leda till höga kostnader, begränsad flexibilitet och minskad effektivitet. En intressant aspekt som studien lyfte var att den tidigare forskningen främst fokuserar på att minska travel distance, medans studiens empiriska underlag visade att företag främst fokuserade på att öka plocksäkerhet och produktivitet. Studiens resultat presenterades som en rekommendation för hur Airshoppen Travel Retail kan designa sin lagerlayout. Resultatet visade vikten av att välja system i samband med kontrollregler för att undvika låsningar i layouten, att plocka i zoner kan leda till ökad effektivitet. Slutligen krävs noggranna kalkyler för företaget att avgöra om automation är en nödvändig och lönsam investering. / The purpose of the case study was to investigate what Airshoppen Travel Retail could take into consideration when designing their new warehouse layout. In order to carry out the study, a theoretical model was developed, the model focuses on how warehouse layout could be designed. The theoretical model analyzes the warehouse layout of two companies. The findings were then used to analyze and give recommendations to Airshoppen Travel Retail regarding what the company could take into consideration when designing their new warehouse layout. Interviews and observations showed that the development of the warehouses processes was adapted and limited by the lack of space in their warehouses. Previous research suggested that the design of a warehouse should be based on the choice of system, either manual or automatic. Inadequate design can lead to high costs, limited flexibility and reduced efficiency. An interesting aspect that the study highlighted was that the previous research mainly focuses on reducing travel distance, while the study's empirical basis showed that companies primarilyfocus on decreasing picking errors and increasing productivity. The results of the study were presented as recommendations to Airshoppen Travel Retail on how the company could design their new warehouse layout. The results showed the importance of choosing systems and control policies simultaneously to avoid limitations in the layout. Furthermore, with a manual system, implementation of zone picking could lead to increased efficiency. On a final note, careful calculations are required for the company to properly determine whether automation is a necessary and profitable investment.

<p>Land use planning has gained popularity as a travel demand management strategy for the last two decades. Many urban authorities in North America have adopted smart growth policies in order to curb auto use and promote sustainable forms of travel, namely, public transit, bicycle and walking. The purpose of this study is to examine whether someone’s travel behavior is influenced by the characteristics of the built environment where one lives and works. The study area is Halifax Regional Municipality, Nova Scotia, Canada. Two aspects of travel are analyzed for a weekday: total distance travelled by auto and average tour complexity. Separate models are developed for worker and non-worker by applying ordinary least square and spatial lag modeling techniques. The built environment variables are measured near home and workplace and at different geographical scales. The average auto distance and tour complexity are separately regressed against the built environment variables while personal characteristics, household attributes, preferences for residential location and transport mode, and meteorological conditions of survey days are accounted for. The results of auto distance models suggest that people living and working in high accessibility areas with mixed land uses make shorter travel by auto, which supports the claims of smart growth proponents. The built environment variables make significant contribution to the fitness of auto distance models. In case of tour complexity models, built environment variables also appear to be significant but with lower contribution to model <em>R²</em>. The results suggest that non-workers, who live in poor accessibility areas, make more complex tours. Workers living in poorly accessible neighborhoods and working in highly accessible areas make complex commuting and work-based, non-work tours. It means that, workers compensate poor neighborhood accessibility by trip chaining near workplace. The findings would be helpful to evaluate the existing growth strategies in Halifax Regional Municipality. In addition, it makes several contributions to the literature.</p> / Master of Arts (MA)

<p>A central theme in animal ecology is the study of the relationship between ecology and behavior. This dissertation demonstrates how ecological parameters, particularly food and weather variables, correlate with ranging, activity budget, and diet in Udzungwa red colobus monkeys (URC, <italic>Procolobus gordonorum</italic>), endemic to the Udzungwa Mountains, Tanzania. </p><p> From April 2009 - March 2010, four URC groups were habituated and studied in Mwanihana and Magombera Forests. During all-day follows, ranging, activity budget, and diet data were collected using GPS units and ten-minute scan samples of sustained activities. Food characteristics were assessed using transect and phenology surveys. Preliminary nutritional analyses were conducted on species-specific parts fed upon during October. I designed and employed novel methods for estimating ranging statistics which were compared with conventional methods.</p><p> Home range sizes were relatively small (8.8 - 20.8 ha). Home range size may relate to food species diversity and feeding selectivity for species-specific food parts. Variability in dietary composition was partly explained by plant phenology, forest composition, and selectivity differences among groups. URC primarily fed upon young leaves with higher fat content. Some non-nutritive items eaten may function as detoxifying agents. Data suggest that the URC dietary strategy involves nutrient balancing (i.e. maximizing energetic intake and nutrient acquisition while avoiding high concentrations of particular plant secondary compounds).</p><p> Mean daily travel distance (DTD) was 970 m, longer than in other red colobus taxa. DTD was shorter in October and November when temperatures were warmer and a high abundance of young growth became available. Young growth comprised the majority of all groups' diets in each sample period. When young growth abundances were highest, Magombera groups traveled shorter distances. One group's DTD did not differ seasonally and was significantly longer compared to other groups. This group may have traveled longer distances and spent less time resting in order to consume young growth in a habitat with lower young growth abundances. A correlation between time spent resting and temperature suggests behavioral prevention of hyperthermia. URC energetic strategies may involve balancing thermoregulation with maximizing energy intake. Conservation recommendations are discussed and include stricter forest protection.</p> / Dissertation

This thesis aims to explore how the urban form specifically sprawl affects travel behavior and travel distance in Riyadh. Since the city is expanding and the travel time gets longer, the first mode option is the car. The research question that reframes this thesis is, how does the urban form 'sprawl' affect travel behavior and distance in Riyadh specifically 'Al-Narjis and Al-Malaz' based on their density and land use. In order to respond to the thesis question, a qualitative research design including mixed qualitative methods has been used. This study conducted a web survey for Riyadh citizens, this survey got 6312 respondents. In addition, this study conducted in-depth online interviews including travel itinerary diaries with six participants, three from each of the two neighborhoods in the study area. The interviews' outputs were visualized through QGIS by producing six maps. The results indicate that travel behavior and travel distance in Riyadh are affected negatively by sprawl. This effect could be seen in the high dependency on automobiles that resulted from land use and city planning, longer trips due to disconnected streets, and poor service accessibility. As well as less usage of other transportation such as walking and cycling due to the lack of pedestrian infrastructure.

<p>This study explores telecommuter travel behaviour by examining discretionary travel distance and mode choice. The study utilizes data obtained from the 2005 origin-destination survey conducted by TRANS, a joint transportation planning committee serving the National Capital Region of Canada. The study compares and explains the discretionary travel behavior of teleworkers relative to other population groups and identifies that the average teleworker travels 3 times farther than regular workers and 1.7 times farther than non-workers for discretionary purposes. Regression indicates that dependent children, vehicle accessibility, housing type, residential distance to the urban core, land-use mix, residence within a Greenbelt region and day of the week all positively affect travel distance. Conversely, age, proximity to shopping centers and inclement weather demonstrate significant negative effects. Then, through binary logistic regression, the study confirms that work status significantly influences mode choice. Similarly, the following predictor variables demonstrate a significant positive effect towards active mode choice: teleworker work status, larger household size, greater income, warmer temperature, closer proximity to shopping centers, apartment housing type, trips for recreational and restaurant purposes, taking subsequent trips in a day, and travel between 8:00 A.M. and 4:00 P.M. On the contrary, increased entropy, trips within the Greenbelt region, dependent children under 16 years old, increased vehicle accessibility and trips for transporting someone or for shopping purposes all reduce the probability of active travel mode choice.</p> / Master of Arts (MA)

My thesis deals with the construction of on-board computers for a motorcycle. The scheme is based on the parameters of onboard computers appearing on the market. In comparison with the models, which are offered commercially it also allows measurement of the motorcycle’s fuel consumption and location by using GPS. On-board computer measures speed, traveled distance, motor speed and engine temperature. It is controlled by a pair of eight-bit AVR microcontrollers. The measured data are showed by a graphical LCD display with touch screen.

This master thesis analyzes the influence of psychological barriers of consumers from Germany, Sweden, and Iran for using sustainable transportation modes. Climate change has started to change the way people travel. Yet prior research has shown that consumers from all over the world lack consistency between their behavioral intention and their actual behavior. In the case of traveling, this means that a significant number of consumers intends to use sustainable transportation modes, but fails to use them in the end. The reasons for this so-called intention-behavior gap in consumers' minds have been researched successfully and frequently in the past two decades. The novelty of this present thesis is the international comparison of travelers from three different countries and the explicit focus on voluntary travel. The according research questions are: RQ 1:  To what extent is there a gap between the intention and behavior of leisure travelers          regarding choosing sustainable transportation vehicles? RQ 2:  Which group of consumers (inclined abstainers or disinclined actors[1]) plays the bigger      role in creating this gap? RQ 3:  What are the determinants and barriers of using more sustainable transportation     vehicles in leisure transportation? RQ 4:  How is the sustainable behavior of leisure travelers in Sweden, Germany, and Iran            different? To answer the research questions, an online survey in Swedish (n1 = 130), German (n2 = 128), and Persian (n3 = 127) language was carried out ( ∑ n = 385) in April 2020 with a convenience sampling method and analyzed in May 2020. The results show that there is a slightly positive intention-behavior gap in the Swedish sample and a slightly negative intention-behavior gap in the Iranian sample. In the German sample, no significant intention-behavior gap has been found. Moreover, a higher level of environmental attitude, a higher level of environmental knowledge, a higher level of perceived effectiveness (of the consumers' own actions), and a higher level of social norms increases the intention of leisure travelers in Sweden, Germany, and Iran to use sustainable vehicles for leisure traveling - both for short and for long trips. The impact of perceived value and perceived price of sustainable transportation modes, as well as the impact of consumers' sustainable lifestyle on the on the travel intention are not supported in all three countries. Additionally, distance between origin and destination has been found to moderate the impact of determinants on intention. The moderating role of distance also varies in different countries. [1] See the literature review chapter for an explanation