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| 2. |
- Frisk, Mikael, et al.
(författare)
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Route optimization as an instrument to improve animal welfare and economics in pre-slaughter logistics
- 2018
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Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 13:3
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Tidskriftsartikel (refereegranskat)abstract
- Each year, more than three million animals are transported from farms to abattoirs in Sweden. Animal transport is related to economic and environmental costs and a negative impact on animal welfare. Time and the number of pick-up stops between farms and abattoirs are two key parameters for animal welfare. Both are highly dependent on efficient and qualitative transportation planning, which may be difficult if done manually. We have examined the benefits of using route optimization in cattle transportation planning. To simulate the effects of various planning time windows and transportation time regulations and number of pick-up stops along each route, we have used data that represent one year of cattle transport. Our optimization model is a development of a model used in forestry transport that solves a general pick-up and delivery vehicle routing problem. The objective is to minimize transportation costs. We have shown that the length of the planning time window has a significant impact on the animal transport time, the total driving time and the total distance driven; these parameters that will not only affect animal welfare but also affect the economy and environment in the pre-slaughter logistic chain. In addition, we have shown that changes in animal transportation regulations, such as minimizing the number of allowed pick-up stops on each route or minimizing animal transportation time, will have positive effects on animal welfare measured in transportation hours and number of pick-up stops. However, this leads to an increase in working time and driven distances, leading to higher transportation costs for the transport and negative environmental impact.
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| 3. |
- Göthe-Lundgren, Maud, et al.
(författare)
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Cost allocation in collaborative forest transportation
- 2010
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Ingår i: European Journal of Operational Research. - : Elsevier BV. - 0377-2217 .- 1872-6860. ; 205:2, s. 448-458
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Tidskriftsartikel (refereegranskat)abstract
- Transportation planning is an important part of the supply chain or wood flow chain in forestry. There are often several forest companies operating in the same region and collaboration between two or more companies is rare. However, there is an increasing interest in collaborative planning as the potential savings are large, often in the range 5–15%. There are several issues to agree on before such collaborative planning can be used in practice. A key question is how the total cost or savings should be distributed among the participants. In this paper, we study a large application in southern Sweden with eight forest companies involved in a collaboration. We investigate a number of sharing mechanisms based on economic models including Shapley value, the nucleolus, separable and non-separable costs, shadow prices and volume weights. We also propose a new allocation method, with the aim that the participants relative profits are as equal as possible. We use two planning models, the first is based on direct flows between supply and demand points and the second includes backhauling. We also study how several time periods and geographical distribution of the supply and demand nodes affect the solutions. Better planning within each company can save about 5% and collaboration can increase this about another 9% to a total of 14%. The proposed allocation method is shown to be a practical approach to share the overall cost/savings.
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| 4. |
- Göthe-Lundgren, Maud, 1952-, et al.
(författare)
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Cost allocation in forestry operations
- 2006
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Ingår i: 12th IFAC Symposium on Information Control Problems in Manufacturing,2006. - Paris : Elsevier Science.
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Konferensbidrag (refereegranskat)abstract
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| 5. |
- Karlsson, Jenny, et al.
(författare)
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RoadOpt : a decision support system for road upgrading in forestry
- 2006
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Ingår i: Scandinavian Journal of Forest Research. - : Informa UK Limited. - 0282-7581 .- 1651-1891. ; 21:S7. 7, s. 5-15
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Tidskriftsartikel (refereegranskat)abstract
- Road blocking due to thawing or heavy rains annually contributes to a considerable loss of profit in Swedish forestry. Companies have to build large stocks of sawlogs and pulplogs to secure a continuous supply during periods where the accessibility of the road network is uncertain. This storage leads to quality deterioration, which means loss in profit. One approach to reduce the losses due to blocked roads is to upgrade the road network to a standard that guarantees accessibility throughout the year. This article describes a decision support system called RoadOpt for the planning of forest road upgrading. The planning horizon is about one decade. The system uses a Geographical Information System (GIS)-based map user interface to present and analyse data and results. Two important modules are the Swedish road database, which provides detailed information about the road network, and an optimization module consisting of a mixed integer linear programming model. A case study from a major Swedish company is presented.
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| 6. |
- Rönnqvist, Mikael, et al.
(författare)
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Collaboration and optimization in farmland exchanges
- 2023
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Ingår i: International Transactions in Operational Research. - : John Wiley and Sons Inc. - 0969-6016 .- 1475-3995. ; 30:4, s. 1591-1616
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Tidskriftsartikel (refereegranskat)abstract
- To keep businesses competitive in world markets, the number of farms in most countries is decreasing while farm size is increasing, and parcels making up the farm area are extremely fragmented. It is common for farms to expand faster than available arable land near the farm center, leading to longer distances between the farm center and field areas. Consequently, logistic costs increase and affect the farm's profitability and the environment. Moreover, there is often substantial overlap between different farms, which implies that it is possible for farmers to collaborate with each other. We developed and proposed three optimization models to describe different levels of collaboration and sharing restrictions. Many practical considerations need to be weighed, such as the soil type and crops used. We collected detailed information on farms, parcels, and cost drivers in seven large instances for our case study in Sweden. One instance had 1431 farms and 32,091 parcels with 96 crop types. The resulting optimization models were very large; special pre-processing and optimization techniques were developed for their solutions. The theoretical potential for collaboration in logistic cost reduction was very large, ranging from approximately 10% to 50% depending on the form of the collaboration. Because a large part of costs comes from less use of diesel for transport resources, the reduction in cost is directly related to a reduction in CO2 emissions. © 2022 The Authors. International Transactions in Operational Research
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| 7. |
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| 8. |
- Engström, Jonas, et al.
(författare)
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Planeringssystem för ett effektivare jordbruk
- 2019
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The work presented in this report is one of three different areas of improving the efficiency of agricultural logistics that have been investigated in the project ”Energieffektivisering av Jordbrukets logistik - fördjupning och utveckling”. The three areas are, 1) Shifting of arable land (2) Planning tool for simulating, planning and optimizing logistical work on the farm (3) KPIs for logistics work at farm level to spur efficiency. All three areas are considered important parts in the work of reducing energy consumption and climate impact from agricultural transports and in food production.More efficient agricultural logistics can be achieved through better planning and coordination of all activities throughout the production process. This improved planning then requires decision support to get a holistic grip on the interacting parts of the process. In this report, we have begun the work to investigate how farmers can make agriculture more efficient by having access to good and simple planning and simulation systems, thereby reducing energy consumption and costs at farm level.We have made a review of which systems (for plant cultivation) that are available on the market today (with focus on the Swedish market) and identified shortcomings, gaps and needs for continued development. We have also in a case study exemplified the decisions a farmer make, and which tools are used. In the longer term, the aim is to have tools for simulation, planning and optimization of logistics for agriculture.There are many applications for planning, control and monitoring of agriculture activities on the market, but no purely logistics planning tools. Many of the tools available on the market are de facto not decision support, but rather business support, where the user can fill in the business conditions and to some extent follow the development during the year. For the applications to provide real decision support, they need to be more intelligent by being able to analyze large amounts of data smarter, make simulations of different scenarios and make assessments on plans. Internationally, the range of programs, apps and other IT support for agriculture management is very large, but the gaps are mainly the same. However, it is not easy to apply an internationally developed tool to Swedish conditions and regulations.
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| 9. |
- Frisk Garcia, Madeleine, et al.
(författare)
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Examining property and neighborhood effects on perceived safety in urban environments : Proximity to square and heights of buildings
- 2024
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Ingår i: Cities. - : Elsevier Ltd. - 0264-2751 .- 1873-6084. ; 150
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Tidskriftsartikel (refereegranskat)abstract
- Residents’ perceived safety is key to improving livelihoods and reducing disparities between neighborhoods in Sweden. Neighborhood interventions may be more cost-effective than individual-level interventions in addressing major societal issues such as unequal levels of safety between neighborhoods. However, most studies investigating the impact of neighborhood characteristics on perceived safety suffer from either poor data quality, too few respondents per statistical unit, large units of analysis, or a lack of longitudinally collected data. This study aims to fill this gap by combining property-specific longitudinal sociodemographic data with customer satisfaction survey data (N = 147,965) collected between 2013–2014 and 2016–2021 in Gothenburg. Using two multilevel models, we examined the relationship between perceived safety and both property-level and area-level structural characteristics, testing three hypotheses. Consistent with prior research, we find that sociodemographic and urban environmental characteristics influenced perceptions of safety. The multilevel analyses reveal that proximity to the square is associated with lower levels of perceived safety, particularly among residents living within 0–100 m of the square in socioeconomically disadvantaged neighborhoods. Moreover, the results show that living in taller buildings of 10–16 floors is associated with lower levels of safety.
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| 10. |
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