Zugl.: Bielefeld, Universiẗat, Diss., 1994.

Universiẗat, Diss.--Basel, 1996.

Thesis (doctoral)--Hochschule St. Gallen für Wirtschafts-, Rechts- und Sozialwissenschaften, 1996.

This bachelor thesis will, through a method study, make an overlook of hypothetical movement patterns and travel routes in northern Sweden between Mesolithic sites/settlements.The common interpretation of the early movement patterns of northern Sweden has been heavily based on waterways as travel routes. With the building of dams along the major rivers in northern Sweden since 1940s many sites have been found along these rivers. This thesis will explore alternative routes based on least cost path analyses and movement patterns over land.Through data of topographic elevation and the Least Cost Path tool through QGIS, hypothetical connections will appear between the sites. The hypothetical travel routes will be tested with data from the cultural register of Sweden to find sites with similar dating near the routes. Through this thesis connections between sites over a large area will test if people moved through these hypothetical routes.

Taiwan¡¦s feed Industry contributes remarkably to the food supply chain in terms of animal protein production. However, after FMD breakout in 1997 and join WTO, feedmill companies with past glories start to erode their advantages in the industry ending up termination of business or struggling the competition. Competitive strategies of¡ucost leadership¡vand ¡udifferentiation¡v proposed by Michael Porter, the strategist, clearly pinpoint out the sustainability in competitive advantages. Those outstanding feedmill companies in different regions that can survive through the tough industry challenges and keep expanding their businesses in a successful manner coincide with these two criteria to compete in the industry. By analyzing the competitive advantage in theory and demonstrations, we also apply these ¡§cost leadership¡¨ and ¡§differentiation¡¨ criteria to the case study Greatwall Group as the suggestive sustainable competitive advantages strategies for the coming challenges in the feed industry. Competitive advantage rigidity could be lessened by meeting the ¡§cost leadership¡¨ criteria by reforming the purchasing model using e-commerce, and ¡§differentiation¡¨ strategy by 1) upgrading the nutrition formulation concept to modeling operation considering the integration advantages; 2) re-allocating the resources in service including research, quality control and vet diagnosis. In the mean times, management restructuring to reinforce the leadership and implementation performance will also be the inevitable requirements. Hopefully through the study of this case, it also sheds lights on other feedmill companies as a learning model.

The study of ancient Maya causeways is crucial for understanding Maya social and spatial organization. Archaeologists have been interested in Maya causeways for decades, specifically documenting their locations. More recently, the use of Geographic Information Systems, or GIS, has been used for understanding the spatial organization of archaeological sites. GIS analyses on ancient Maya causeways however have been very limited. This thesis aims to evaluate ancient Maya causeways through GIS analysis. Specifically, five intersite causeway systems are looked at: the Mirador Basin, Yaxuna-Coba-Ixil, Uxmal-Nohpat-Kabah, Ake-Izamal-Kantunil, and Uci-Kancab-Ukana- Cansahcab. These causeway systems were evaluated using least-cost paths based on the terrain. In this thesis, I argue that the intersite causeways do not follow a least-cost path based on terrain and that the purpose of these roads varies between sites and regions.

The Geographic Information System (GIS) is a crucial part of any land navigation system. Autonomous ground vehicles should have access to stored geographic data and the ability to manipulate it for routing purposes. Since there is no human interaction involved in operating these vehicles, data that a human driver would use to make decisions must be stored in the GIS. The data which represent the earth's surface become a series of factors and constraints which translate to friction in terms of mobility. Factors need to be weighted appropriately, but require a sensitivity analysis before designating these weights. Constraints do not require any weight because they represent absolute barriers which cannot be traveled upon. All GIS layers are incorporated into the raster environment, so that an accumulated surfaces can be built on which a least-cost path can be located. The sensitivity analysis allows generation of many routes which can be field tested for the appropriate weight selection for each factor. Ultimately, the entire process would select an optimal path and output closely spaced waypoints which the vehicle can follow. / Master of Science

In the past several years, the Defense Advanced Research Projects Agency (DARPA) has sponsored two Grand Challenges, races among autonomous ground vehicles in rural environments. These vehicles must follow a course delineated by Global Positioning System waypoints using no human guidance. Airborne LIDAR data and GIS can play a significant role in identifying barriers and least cost paths for such vehicles. Least cost paths minimize the sum of impedance across a surface. Impedance can be measured by steepness of slope, impenetrable barriers such as vegetation and buildings, fence lines and streams, or other factors deemed important to the vehicle's success at navigating the terrain. This research aims to provide accurate least cost paths for those vehicles using airborne LIDAR data. The concepts of barrier identification and least cost path generation are reviewed and forty-five least cost paths created with their performance compared to corresponding Euclidean paths. The least cost paths were found superior to the corresponding Euclidean paths in terms of impedance as they avoid barriers, follow roads and pass across relatively gentler slopes. / Master of Science

In the planning and design of sewer networks, most of the decisions are spatially dependent because of the right of way considerations and the desire to have flow by gravity. This research addresses the application of combined optimization-geographic information system (GIS) technology in the design process. The program developed for the design uses selected manhole locations to generate the candidate potential sewer networks. The design area is delineated into subwatersheds for determining the locations for lift stations when gravity flow is not possible. Flows from upstream subwatersheds are transported to the downstream subwatersheds via a force main. The path and destination of each force main in the system is determined by applying the Dijkstra's shortest path algorithm to select the least cost path from a set of potential paths. This method seeks to minimize the total dynamic head. A modified length is used to represent the length of each link or force main segment. The modified length is the physical length of the link (representing the friction loss) plus an equivalent length (representing the static head). The least cost path for the force main is the path with the least total modified length. The design approach is applied to two areas in the town of Blacksburg, Virginia. The resulting network and the force main paths are discussed. / Master of Science

Least Cost Path Analysis (LCPA) is a GIS-based approach for calculating the most efficient route between a start and end point, often in terms of shortest time or least amount of energy. The approach is often applied in archaeology to estimate locations of sites, and routes between them. We applied LCPA to estimate how sites in the Andes in the eastern portion of the Inka empire may have connected to sites in the western Amazon Basin. Our approach further used the known Inka Road network to test performance of two types of LCP models (linear vs. areal calculation) and four types of cost functions. LCPs can be calculated with an areal approach, where each cell of the DEM is given one overall slope value, or linearly, where the direction of travel across a cell affects the slope value. Four different algorithms were tested: Tobler's Hiking Function (1993), Tobler's Hiking Function with a vertical exaggeration of 2.3 based on human perceptions of slope (Pingel 2010), Pingel's empirical estimation approach (2010), and Pandolf et al.'s energy expenditure equation (1977) using both an areal and linear approach for all the algorithms. An initial study was conducted in the Cusco region and results were compared to the Inka Road network using the linear accuracy assessment method of Goodchild and Hunter (1997) and Güimil-Fariña and Parcero-Oubiña (2015). The findings suggest that the empirical estimation and caloric cost methods were the most accurate and performed similarly, both were more accurate than travel-time based costs, and linear methods were better than areal based methods when using higher resolution DEM inputs. / Master of Science / Least Cost Path Analysis (LCPA) is a method used for determining the most efficient route between a start and end point, often in terms of shortest time or least amount of energy. The approach is often applied in archaeology to estimate locations of sites, and routes between them. We applied LCPA to estimate how sites in the Andes in the eastern portion of the Inka empire may have connected to sites in the western Amazon Basin. Our approach further used the known Inka Road network to test performance of two types of Least Cost Path (LCP) models (linear vs. areal calculation) and four types of cost functions. LCPs can be calculated with an areal approach, where each cell in an elevation dataset is given one overall slope value, or linearly, where the direction of travel across a cell affects the slope value. Four different ways of calculating cost were tested: Tobler's Hiking Function (1993) using time as a cost, Tobler's Hiking Function with a vertical exaggeration of 2.3 where the cost is based on human perceptions of slope (Pingel 2010), Pingel's empirical estimation approach (2010) based on the preexisting Inka Road system, and Pandolf et al.'s energy expenditure equation (1977). All four ways of calculating costs were used both an areal and linear approach. An initial study was conducted in the Cusco region and results were compared to the Inka Road network by seeing what percent of each LCP was within 500 m of the Inka Road. The findings suggest that the empirical estimation and energy based methods were the most accurate and performed similarly, both were more accurate than travel-time based costs, and linear methods were better than areal based methods when using higher resolution elevation data inputs.