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本文应用季节指地和指数平滑法,以微机为工具,对林业汽车运输企业的木材运输量进行预测,探索一种简便适用的木材运输量预测方法,为企业科学地制定运输计划提供依据。 相似文献
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党凤兰 《绿色中国(A版)》1986,(5)
线性规划是运筹学中研究比较早,而且比较成熟的一个分支。近几十年来,线性规划在经济管理方面的应用得到了飞速的发展。目前,有些国家应用线性规划已取得了比较成功的经验。例如,苏联卡累里州森工联合公司利用线性规划编制木材计划,使计划更为准确,并且提高了木材平均售价,降低了非生产性消耗,减少了企业同时生产材种的数目。又如加拿大林业产品有限公司,在1967年,根据已知的生产限制,编制了一个线性规划模型,以确定现有木材品种和销售需要之间的最优平衡方案。使用这一规划模型的结果,该部门的贡献幅度,1970—1975年间与1969年相比,每年平均增长100万美 相似文献
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本文讨论的是灰色系统在家具生产中的应用。采用的方法是用灰色线性规划取代传统的线性规划，为茶几生产建立了灰色规划模型，从而满足了家具生产的动态特征。从解的结果看，灰色线性规划在制定家具生产计划方面是切实可行的。 相似文献
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《林业工程学报》2016,(5)
为了提高林业执法干部的木材运输稽查水平,需要向执法人员提供周边地形地貌、林地资源和运输车辆的位置信息。基于Mobile Web GIS理念,应用Microsoft Visual Studio 2010的C#.net语言开发了林业运输稽查系统。系统分为两个部分:一是智能手机终端的定位程序读取GPS模块测量的位置信息,并通过GPRS上传至互联网上的云数据中心;二是云数据中心通过ASPMAP组件绘制村庄的道路、村界、等高线和林地小班的地理信息,然后叠加显示运输车辆和执法车辆的位置,以Web GIS网页的形式向手机端发布。成功开发了林业运输稽查系统,林业执法干部在手机终端的支持下,能更有目的性地开展运输稽查工作,追查木材来源,追踪车辆轨迹。系统的应用使林业运输稽查实现了可视化管理,降低案件的调查难度,提高了林业干部行政执法能力。 相似文献
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GIS-based decision support system for wood logistics 总被引：1，自引：0，他引：1
QiuRongzu EskoMikkonen 《中国林学(英文版)》2004,6(4):29-33
A wood logistics system was combined with a linear programming (LP) method utilizing GIS-based techniques on the platform of GIS soflware-ARC/INFO. The combined costs of road and off-road transport were taken as the objective function to find the least cost route and the optimal landing locations of wood transportation. Then transport costs and allowable wood volume of stands were calculated. An LP model was developed to allocate timber resources among mills in order to minimize the wood logistics costs from harvesting sites to mills. The parameters of the LP model, including the transport costs, allowable wood volume and wood orders, were written into a text file in MPS format which were then accessed by LINDO to solve the LP problem. The system is an effective tool to manage logistics, information and funds together in order to increase the speed of wood logistics and reduce the cost.The benefits and efficiency of mill cluster can be improved. The focal firm in the cluster can be competitive. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(7):689-700
Availability of solid by-products from wood harvesting and mechanical wood processing was estimated as sources for energy production based on recent actual harvesting, sawmill, and plywood production in Northwest Russia at 30 million m3. Nearly 70% of the energy wood, 20 million m3, was from harvesting, consisting of non-industrial round wood, unused branches and tops, defective wood resulting from logging, and spruce stumps removed after final felling. Over 30%, 10 million m3, of the available volume was from sawmills and plywood mills, i.e. wood chips, sawdust, and bark. Due to current low utilization of energy wood for bioenergy in Northwest Russia, delivery cost of energy wood to the potential border-crossing points in Finland was analyzed for three means of transport: railways, roadways, and waterways. Nearly 28 million m3 of the energy wood could be transported by railways and 2 million m3 by roadways and waterways. The costs were lowest by roadways from the nearby border areas (10–15 €/m3 for wood processing by-products and 16–22 €/m3 for forest chips). The costs by railways varied from 12 to 27 €/m3 on shorter distances to 47–58 €/m3 on longer distances. Waterway transportation was the most expensive, about 28–48 €/m3. It should be emphasized that we have estimated availability and delivery costs of energy wood, not prices which are defined by the market based on supply and demand. 相似文献
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Franz Holzleitner Christian Kanzian Karl Stampfer 《European Journal of Forest Research》2011,130(2):293-301
Round wood supply in Austria is often affected by different factors such as bottlenecks or oversupply due to changing market, weather and road conditions. An additional factor impacting the complex wood supply chain is the rising transport costs from the landing to the sawmill. Logging trucks are the primary transportation technology used from the forest to the customer??s site. The objectives of this study were to analyze the actual situation and characteristics of typical trucking activities for round wood supply from the region to an Austrian sawmill. The study used time and fuel consumption, proportion of travel on forest roads and average speed on different functional road classes to estimate productivity and costs. Data collection including GPS-tracking was done using fleet management equipment built into the driver??s cabin. The GPS-routes were analyzed in ArcGIS 9.3 based on the national road network and its attributes. The sawmill studied with a yearly demand of 600,000 m3 round wood was located in southern Austria. In total, more than 2,000 round trips operated by seven logging trucks recorded close to 100,000 km. The transport distance from the forest to the sawmill averaged 51 km. The average share on forest roads within a route to the sawmill was 14.2% with an average speed of 13.5 km/h, whereby the forest road is defined as road with minor importance. Transport costs from the forest site to the sawmill with a truck and trailer were ? 11/m3 solid timber based on an average load size of 25 m3. An average 0.77 l of diesel fuel per kilometer was consumed during a round trip including all work phases. A trip to an interim storage location consumed 2.05 l/km due to the number of work phases without driving distance. 相似文献
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Fraefel Marielle Bont Leo G. Fischer Christoph 《European Journal of Forest Research》2021,140(5):1195-1209
Efficient forest management, and wood production in particular, requires a forest road network of appropriate density and bearing capacity. The road network affects the choice of a suitable extraction method and the length of the transport route from the forest, while the road standard defines the truck type that can be used.
We evaluate the forest road network’s economic suitability for harvesting operations in the entire Swiss forest, an area of about 13,000 km2 covering a range of topographies, based on the Swiss National Forest Inventory’s (NFI) forest road dataset. This dataset is based on information from an interview survey with the local forest services and includes all forest roads in Switzerland capable of carrying trucks. Extraction options and hauling routes are analysed together; thus, the entire logging process is examined.
Model results include maps of the most suitable extraction method; extraction costs; hauling costs; and a suitability map based on a combination of the results. While the larger part of the Swiss forest is classified as “suitable” for economic harvesting operations, significant portions also fall into the “limited suitability” and “not suitable” categories. Our analysis provides an objective, country-wide, spatially explicit assessment of timber accessibility. The resulting suitability map helps identify areas where timber harvesting is economic using the current forest road network, and where it is not. The model results can be used in road network planning and management, for example, by comparing road-network re-design scenarios, and compared to the spatial distribution of available wood volume.
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《Scandinavian Journal of Forest Research》2012,27(4):390-402
Forest management planning comprises selection among treatment alternatives in management units. A traditional linear programming (LP) approach may effectively account for a profit maximization objective combined with sustainability constraints, e.g. on the temporal distribution of harvest volume flows, cash‐flow, and net present value development, but it fails to account for spatial constraints, especially those associated with final felling. By applying a simulated annealing adjacency model based on net present value maximization and combined with an LP consequence computation model, it is possible to delineate optimal strategies of final felling scheduling. Evaluation is made of the trade‐off between (1) the incremental cost (determined by use of the LP model) of an optimal adjacency model solution, and (2) the potential damage cost resulting from adjacency characteristics such as windthrow and bark injuries. The decision support system may contribute significantly to reduce damage costs and may improve the reliability of forest management planning. 相似文献
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针对道路运输企业营运车辆运行过程中燃油消耗状态难以监控的实际情况,本文设计了以单片机STC89C52为核心的车载油耗实时监测系统.提出监控系统的总体设计方案,搭建由电源处理模块、单片机主控模块、油耗数据采集模块、GPS定位模块、GPRS无线通信模块和数据存储模块构成的硬件系统,开发系统控制软件和上位机油耗管理软件.该车载油耗实时监测系统操作方便,成本较低,兼容性强,具有广阔的应用前景.能够对营运车辆行车过程中的实时耗油量进行统计分析,结合生产计划进行燃料供给管理工作,能够有效改善道路运输企业的燃油浪费现象,实现节能增效的目的. 相似文献
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Combining stand simulation and forest-level optimization is an efficient way to study harvest scenarios of a forest area. A simulator first generates for each treatment unit a number of treatment schedules. Linear programming (LP) can then be used to study how stand-level schedules can be combined at the forest level with respect to alternative goals and constraints. The special structure of the obtained LP problems can be utilized using the generalized upper-bound technique which takes care of the so-called area constraints. JLP software was based on this technique. Later J software was developed to replace JLP. Now J is developed to deal with factory problems where the transportations costs and capacities of factories are included in the problem definition. The generalized upper-bound technique was modified to handle transportation constraints which tell that each timber unit produced is transported to some of the factories. The number of these constraints is very large. This paper describes the basic features of the algorithm and its implementation in the J software. 相似文献
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Hans R. Heinimann 《Journal of Forest Research》1998,3(1):1-9
Road spacing on slpes depends on the underlying off-road transportation technology. One major decision in road network planning
is to determine under what terrain conditions ground- or cable based extraction systems should be applied. The present investigation
aims to develop a road spacing model for steep slope conditions and to implement a total cost model for skidder and cableyarder
based road network concepts. The study analyzes transportation and road geometry to specify the relationship between road
density, slope gradient, and road spacing. Production functions for skidder and yarder-systems make it possible to derive
transportation cost as a function of road density and slope gradient. A total cost function integrates road building cost,
harvesting strategy, and production economics to derive optimal road density for the two network concepts. The difference
between the cost levels at optimum road density is an indicator for differentiating cable and skidder-based extraction systems.
The model was implemented as a Visual Basic add-in for Microsoft Excel spreadsheet software. This flexible approach makes
future adaptations and changes very easy due to the modular concept. The validity of the model is limited to the production
functions of the underlying off-road transportation technologies. Future work needs to develop production functions for the
state-of-the-art technologies and to improve the road building cost model. 相似文献
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从道路运输工具、运输行业管理和道路运输基础设施3个方面分析影响道路运输业节能减排的因素,结合国家和地方颁布的相关法规政策,以区域道路运输行业节能减排的评价为目标,明确道路运输业节能减排评价指标体系的设计依据,建立道路运输业节能减排评价指标体系. 相似文献