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425 Uppsatser om Volume haptics - Sida 5 av 29
Hur enkel- & dubbelportsturbin i kombination med två olika avgassamlare påverkar gasväxlingsprestanda på en Scania V8
The exhaust arrangement on a Scania V8 consists of one manifold at each bank connected to a twin entry turbine (8-2-2). A study in GT-Power has shown improved performance and reduced cylinder to cylinder variations using two manifolds at each bank in combination with a single entry turbine (8-4-1). This thesis work analyses the difference in performance shown in simulation and verify it by engine test.The initial work was focused on simulation in GT-Power. Investigating how exhaust manifold volume and pulses effects the turbine efficiency and the mean effective pressure during the gas exchange. To verify GT-Power simulations four engine tests with different exhaust arrangement have been made.The results from GT-Power simulation indicate that a larger exhaust volume improve the turbine efficiency.
Jämförelse av fyra rundbalspressars packningsförmåga som funktion av grödans torrsubstanshalt :
To succeed, and make money at your animal production you need to feed your animals with
high quality fodder. Other condition to succeed is that you keep your production costs at a minimum. To be able to produce baled silage at a low cost it?s very important that the bales have a high density. Density is measured in kg dry matter (DM) per cubic meter.
The purpose with this report was to learn more about making silage in round bales and to how much the bale density varies between different brands of round balers.
Data och metodik för utbytesberäkning - en studie på Medelpads Skogsförvaltning
To manage the industry?s need of wood assortments in a optimal and cost effective way the forest companies need to have knowledge of the actual standing volume and the yield of the planned clear cuts. The mean volume of the trunk is also important since it is important for the contractors prices. Today the total volume are estimated either with Näslund (1940) or Brandels (1990) functions of volumes, and the yield is estimated with Rune Ollas (1980) function for trunks and stands. The purpose of this study has been to answer the following questions: How good is the yield forecast with data collected with currently used methods? How well can the yield forecasts became with data collected according to the instructions? How well can the yield forecast be with data collected according to the instruction and calculated with the program Aptan for theoretical bucking? The study has been initiated and financed by SCA Skog AB.The material consisted of a number of randomly selected objects ready for clear cut.
Productivity of integrated harvesting of pulpwood and energy wood in first commercial thinnings
The aim of this study was to quantify the productivity and the costs of different harvesting systems (teams), containing harvesters equipped with accumulating harvester heads and forwarders, in first commercial thinnings were an integrated harvest of pulpwood and energy wood were performed. In the beginning the plan was to study and measure 20 sites before and after harvest. Due to storms during the summer of 2010, complete data could only be obtained from 8 of these 20 sites. Seven of these sites were privately owned and one was owned by UPM, all of the sites had been pre-commercially thinned. The mean stem density before harvest was 2578 stems per ha and the mean stem volume was 0.074 m3solid over bark.On average 1518 stems/ha was harvested.
Kostnader vid gallring med flerträdshanterande aggregat, från skog till industri
Profit in first commercial thinnings of today is hard to achieve. This is because of prevailing pulpwood prices and because of high costs of logging and transport. To reduce these costs higher productivity is advocated. One way to increase the productivity is the use of multi-tree handling harvester heads. The aim of this study was to calculate logging and transport costs in first thinnings, where multi-tree handling has been used.
Placering av lastbärare : Faktorer som styr placeringen av lastbärare i terminal
Purpose: The Essay is written on behalf of a company called ?Uppdragsgivaren?. The purpose is to connect theory with the result of the survey and thereby find the critical factors for an optimal placement of the cargo holders in the company?s terminal. Method: A qualitative case study has been carried out. The theory collection is completed with the result from the survey, which include the information ?Uppdragsgivaren? provides and the result from the survey.
Transportekonomi : Underlag för prisförhandlingar
The report addresses four main tasks, situation analysis of the company's total costs and transportation volume, cost analysis associated with the adjustment of the filling ratio, transport costs for the expansion and new expenses on a combination of expansion with new adjusted filling ratio. Increasing transport costs for the company was the main reason for the request of the current situation analysis. A survey of the total cost with the actual volumes and transport provider pricing is the basis of the analysis that extends from May 2006 to October 2008. The results show an increase in costs, both overall expense and per cubic meter of transported goods. Volume spreads, trends, and seasonal variations are according to our and the company?s expectations.
Identifiering av fel i skogliga beståndsregister med hjälp av satellitdata :
This thesis has focused on the possibility to use a satellite image method developed by Metria Mijöanalys to identify stands that are wrongly registered in Holmen Skogs database. The method is only intended for identifying stand with poor descriptions in Holmen?s database that needs to be updated and not for updating the stand information.
The study area is located several km west of Hudiksvall on the borderline between Gävleborgs- och Västernorrlands län. The area is covered by a SPOT image from 2005. By which Metria Miljöanalys has made estimates of forest parameters for all stands in the area, and compared them with corresponding estimates according to the stand database.
Alla vill beta men ingen vill bränna : skogshistoria inom Särna-Idre besparingsskog i nordvästra Dalarna
In this work I have tried to reconstruct the forest history within Särna-Idre forest common in northern Dalarna from the 19th century until present time.
The Särna-Idre region has been an extensively used landscape for a long time. Pollen which indicates grazing has been found in samples orginating from the 10th century. Early travellers from the 18th and 19th centuries seem to have been passing trough a "used" landscape. Burned forests on naked ground are described as common. Also large areas are mentioned as undisturbed with lots of large trees, snags and dead wood.
Simulering av hydrauliska dämpare i borrslagverk
This master thesis consists of the creation of shock absorber models for percussive rock drills. A model of the rock was also developed. These models were connected to existing models of the rock drill to create a complete simulation of the rock drilling process.When the models had been created the rock model was evaluated by comparison with measured values from lab tests. The verified rock model was then used to evaluate the shock absorber models.Four new shock absorber concepts have been developed. Three of these have been modelled, while the fourth have only been sketched and described.The evaluation of the models showed the following:? Simulations of the single shock absorber don?t correlate to reality very well.
Metod för urval av bäriga bestånd längs med bäriga vägar i Sveaskogs planeringsområde Råneå och Överkalix :
With increased need for flexibility in timber deliveries, forest roads become an important factor. The disintegration of roads during the spring season can be avoided if it is possible to rule cutting areas to stands with good carrying capacity along roads with good carrying capacity.
The goal with this work was to create a method to find the stands with high carrying capacity located near roads with high carrying capacity, and select them into a collection file. The method was based on Esri ArcGIS 9 and the tables that follow within that program.
The method resulted in four different themes:
1. Collections with GYL 100 that cross the bufferzon for 0, 1, 2 and 3 class roads. Result 36 collections.
2. Collections with GYL 100 and 200 that cross the bufferzon for 0, 1, 2 and 3 class roads.
EFFEKTIVARE UTLASTNING FÖR LAGER UNDER HÖGSÄSONG PÅ HUSQVARNA AB
Husqvarna AB operates two warehouses located in the area of Jönköping. The most important task is to manage the large volume fluctuations during the peak season. DHL Exel Supply Chain (DESC) run the warehouses and the domestic transportations is outsourced to DHL Express. A number of forwarder agents are responsible for distributing the export gods. In the present situation a bottleneck occurs at the warehouse loading section, and the consequence is fulfill the time of delivery for all customer orders.
Detaljhänsyn efter slutavverkning : kvantitet och inverkan på framtida produktion hos SCA i Västerbotten
According to FSC (Forest Stewardship Council) shall at least a mean of 10 trees per hectare including riparian zones and other areas with high biological values be left in final felling. In addition large clear areas should not be created and all retained trees with high environmental value shall be spared. To leave trees in final felling means a lower cutting volume and hence a lower income from the cutting, but it also means that the production in the next generation becomes less because of competition. The aim of this study was to evaluate the effect retained trees have on the production in the new generation of forest, and to investigate if there is any way to lower this effect. The environmental care has also been estimated by the amount left in final felling.
Lodgepole pine - stability after thinning
SCA has today almost 300 000 hectares of their forest land planted with lodgepole pine(Pinus contorta var. latifolia). Due to initial extensive planting in the 1970ies the area oflodgepole pine forests in the thinning age has grown rapidly from the end of the 1990ies.During the years 1996-2005 first commercial thinning of lodgepole pine at SCA took place.The goal of the hereby presented study was to investigate the growth and stability in thosefirstly-thinned lodgepole pine stands a few years after thinning. Furthermore, the objectivewas to investigate the relationship between stand stability and different stand parameters.Additionally, lodgepole pine stem quality was estimated.The study is mainly based on the data collected during an inventory project carried out atSCA in 2008. Altogether 91 lodgepole pine stands in northern Sweden were measured afterthe first thinning.
Naturvärden i en värmländsk bruksskog : en skogshistorisk studie av Åbengtshöjden/Bogranghöjden
In this study I have analysed the history of a forest belonging to Saxåhyttan in Värmland. The study area is 448 hectares and has been used by iron industry since the 16th century. A forest that has been used by man during at least 400 years should have few ecological values. This inventory however shows the opposite.
The aim of the study is to interpret the history of the forest in the area, i. e.