Optimal road spacing of cable yarding using a tower yarder in Southern Austria

Cable yarding systems are widely used in mountainous forests of Austria. The goal of this paper is to determine optimal road spacing (ORS) of yarding operations by tower yarder in Styria to help logging planners minimize logging costs. A total of 591 working cycles were used to develop the multiple regression model using stepwise method to predict yarding time per cycle. The production and cost in whole tree uphill yarding were 6.70 m³/PSH and 27.60 Euro/m³, respectively. The roading, yarding and installation cost per cubic meter were computed for different yarding distances and graphed as a function of road spacing. The minimum total cost and ORS were 42.88 Euro/m³ and 261 m, respectively for one-way yarding. For two-way yarding, the minimum estimated total cost, ORS and optimal road density would be 38.48 Euro/m³, 373 m and 26.8 m/ha, respectively. The results showed increasing harvested volume decreases ORS and that increased roading cost increases ORS. The load volume has a significant effect on ORS.     

Location set-covering inspired models for designing harvesting and cable road layouts

One of the classic operations problems in forest management is to select the harvesting system and to plan the layout, which has a significant impact on overall operational and environmental efficiency. This paper addresses the design of a harvesting system in areas characterized by steep slopes requiring cable-based harvesting under central European conditions. We present two computationally efficient methods (designated as set-covering model SCM and bounded set-covering model BSCM) for solving problems of cable road layouts and comparing them with a previously developed model (CaMLOC). Formulating the problem as a type of location set-covering model allowed us to delineate a much smaller problem that was easier to solve. By applying the new model formulations, it is possible to identify mathematical optimal CR layouts for real-world forests areas up to 50 ha within a reasonable period of time and to even estimate the maximum gap in optimality (only with the BSCM approach).     

Effects of geometric design of forest road and roadside vegetation on traffic noise reduction

Geometric design of forest roads and design of their landscapes can reduce noise pollution and its harmful effects on human health. We investigated the effects of technical and biological parameters such as geometric road design and various roadside tree stands on reducing noise pollution according to the tree density and distance from roadway in Darabkola Forests, Sari, Iran. We recorded the noise generated by a car(Land Rover) relative to changes in longitudinal slope, horizontal curve radius and type of road pavement. We also measured noise levels according to roadside tree density and stand type(coniferous and hardwood) in 40 rectangular plots of three widths(25, 100 and 300 m) and 50 m length that were randomly demarcated along forest roads. The changes in noise level were recorded using a decibel meter with an accuracy of ±1.5 d B and resolution of 0.1 d B. Noise levels were higher alongside unpaved roads than alongside paved roads. There was an inverse relationship between the measured noise level and horizontal curve radius. The rate of noise level on horizontal curve with a radius less than30, 30–45 m and more than 45 m were 64.8, 70.8 and75.9 d B, respectively. The noise level increased with the increasing longitudinal slope of the road. There was a significant difference between the noise level on slopes less than 3 %(67 d B) and 3–8 %(71.2 d B) in comparison with slopes greater than 8 %(77.8 d B),(p 0.05). Pinus brutia L. reduced the noise level more(about 6 d B) in stands of1/3 density of mixed hardwoods within 25 m from middle of the road. Careful design of geometric properties of forest roads as well as planting coniferous trees with hardwoods is a suitable solution for reducing noise pollution.     

无卷筒离合器的轻型绞盘机设计

为适应我国山地丘陵多、坡度陡和绞盘机作业强度大、维护不便等特点,提升绞盘机的操作性和转运能力,设计了一种无卷筒离合器的轻型绞盘机,阐述了绞盘机总体布置方案和工作原理,设计了采用齿轮传动的新型选筒机构,取代传统绞盘机的卷筒离合器,传动可靠,制造工艺简单,对选筒机构的花键轴和齿轮进行了强度校核,并对绞盘机传动系统的主要零部件进行了选型与设计,利用Matlab对绞盘机卷筒进行了轻量化优化设计,利用Solidworks进行了卷筒三维建模和有限元分析。结果表明,优化后的卷筒强度满足要求。该绞盘机采用新型的选筒机构,结构紧凑,安全可靠,整机轻量化程度高,便于运输,操作简便,可以有效提升绞盘机的工作效率。     

半悬空集材索道设计系统

本文在半悬空集材索道设计的数学模型及其理论推导的基础上,用高级BASIC语言编程.该系统能对单跨半悬空集材索道的三种类型(两端固定式、松紧式、运行式)分别进行完整的设计计算.并绘制索道纵断面图。     

浅谈平水桥游园的改造设计

平水桥游园的改造，体现了海滨风景旅游度假中蓝天、绿树、碧海、金沙等要素俱全的特色景观，突出了山、海、林的风景旅游度假城市形象，为游人提供了一个亲近自然的环境空间。     

公路养护机械及质量检查与评定

本介绍了公路养护机械、公路养护质量日常检查、公路养护质量定期检查及公路养护质量等级的检查与评定。     

谈乡镇公园的规划与建设

乡镇公园的规划与建设既应有对传统建园手法的继承与发展,也应有其自己的特色。     

悬索式暖棚冬期施工

介绍悬索式暖棚的设计及搭设方式。悬索式暖棚可以取代传统的满堂红架子式暖棚，适合在冬期施工基础或地下室工程。暖棚内无支柱，无障碍，便利施工。     

浅谈园林规划布局

结合多年的园林工作实践，对园林绿地规划设计时应遵循的6大基本原则作了简要的综合论述，为城市园林规划设计、园林艺术布局提供了理论依据，为园林规划的实施提供了技术指导。     

虚交基线支距法——公路平曲线测设的一种高效方法

根据多年的公路测设经验，利用虚交基线结合切线支距法和弦支距法测量原理，总结出一种公路平曲线测设的高效方法－虚交基线支距法。章介绍了虚交基线支距法的计算方法与测设方法。尤其在树木茂密的林区与房屋密集的村镇使用虚交基线支距法测设公路平曲线，既可减轻劳动强度，又可节省时间，提高工作效率；而且测设精度高，不存在误差累计。     

The effect of road traffic on a breeding community of woodland birds

The very rapid development of the road infrastructure in recent years has adversely affected the natural environment. The main effects of this have been the loss or deteriorating quality of habitats, the mortality of animals due to collisions with road vehicles, the withdrawal of birds as a result of disturbance and excessive noise in the neighbourhood of roads. In this study, we attempted to define the influence of a busy road on a breeding community of woodland birds. Individuals were counted using the point method at 54 observation points located at three various distances (60, 310, 560 m) from the road. At each point, we determined the habitat parameters and the intensity of noise. In total, 995 individuals of 39 species were recorded on the study plot. This study showed that the area was homogeneous with respect to habitat. The number of birds per point increased with distance from the road. Species diversity was lower near the road. The density of nine common species increased with distance from the road. Great Tit Parus major and Song Thrush Turdus philomelos preferred the neighbourhood of the road, whereas the numbers of the other species were the highest in the middle row of points. The number and species diversity of birds were correlated with the pattern of sound propagation across our study area. Our results showed that the species particularly sensitive to road traffic were those nesting near the ground and with low-frequency calls.     

落叶松人工林最适密度的探讨

以林分中的优势木和亚优势木的树冠面积,作为单株林木最适宜的生长发育空间,来确定合理的林分密度,并依据林木胸径和树冠面积的密切关系,最终由林分平均胸径来确定林分最适的经营密度。     

公路机械化养护方式的决策方法

本介绍了公路机械化养护方式的决策方法，建立指标体系后，分别对单指标效用函数，定性能标效用函数、多指标效用函数进行建立，应用效用理论最后做出决策。     

Sedimentation associated with forest road surfacing in a bottomland hardwood ecosystem

Access systems are a necessary element of resource production in bottomland hardwood sites. However, road building may have a detrimental effect on hydrologic function of the site. This report describes initial results of a study designed to examine the effect of different road surfacing treatments on water quality.

Four surfacing treatments installed on two test roads included native soil, native soil with vegetative stabilization, 6 cm of gravel, and 15 cm of gravel over geotextile. During the first flooding season periodic sampling measured floodwater suspended sediments and location of erosion and sediment deposition within the road prism. Initial results suggest that sediment movement was confined to the road right-of-way, with no statistically significant sedimentation effects detected beyond the clearing limits of the road. The study is continuing for another field season.     

Forest road design with soil sediment evaluation using a high-resolution DEM

In this study, we combined a program to optimize forest road alignments with a method for prediction of surface erosion and related sediment delivered to streams. Combining the forest road design program with the high-resolution digital elevation model made it possible to estimate soil sediment based on a standard methodology, because a relatively accurate road prism could be generated. The combined program properly places and spaces drainage structures based on the Washington State Forest practice board manual. We applied the program to a part of Capitol State Forest in Washington State and optimized horizontal and vertical alignments while estimating movement of soil sediment from roads to streams. We discussed the effects of road surface materials, near-stream culvert distance to stream, and out-sloped forest road template on total road costs and soil sediment delivered to streams. Using lower quality rock surfacing reduced total costs, but the amount of soil sediment from lower quality rock surfacing was 1.5 times more than that on a higher quality rock traction surface. Therefore, lower quality rock surfacing should not be used near the stream. The placement of near-stream culverts 15 m upstream and out-sloped road template were examined using a traction surface on 15-m sections upstream and lower quality rock surfacing on other sections in order to reduce soil sediments to the stream and total costs. As a result, placing near-stream culverts 15 m upstream and using an out-sloped road template significantly reduced total road cost and soil sediment. Finally, we optimized horizontal and vertical alignments while limiting soil sediment to a specified maximum level. The model successfully optimized forest road alignments, which reduced total road cost as well as soil sediment.     

Runoff and sediment concentration of different parts of a road in Hyrcanian forests

Road prisms, such as cutslopes, fillslopes and road surfaces, can be important contributors of sediment to streams in forested watersheds. In this study rainfall simulations were carried out on cutslopes, fillslopes, road surfaces and forest grounds in hardwood forests of Lolet and Lat Talar, Iran. Water at intensity of 32.4 mm·h 1 was sprayed from a nozzle onto a square area of 0.48 m 2 . Runoff was collected by water gauge every 4 min and then runoff and sediment parameters were measured in each plot. Results indicated that on road surfaces, the runoff coefficient was 63.28%. On the cutslopes and fillslopes, the runoff coefficients were 35.14% and 10.23%, respectively. On the forest ground as a control, the runoff coefficient was 5.90%. Runoff volume was 2.73 mL·s-1 on the road surfaces and 1.52 mL·s-1 on cutslopes. On fillslopes the runoff volume was 0.44 mL·s-1 and on the forest ground 0.25 mL·s-1 . The greatest rate of soil loss was found on the cutslope (280.79 g·m-2·h-1). The total soil loss from the cutslopes was two times higher than that from the road surfaces and six times higher than that from the fillslopes. We conclude that cutslopes can be considered the main source of sediments in our study sites, but the function of road surface as a source of runoff generation is more important.     

CHRIS数据几何校正精度改善研究(英文)

This paper deals with a new type of multi-angle remotely sensed data--CHRIS （the Compact High Resolution Imaging Spec- trometer）, by using rational function models （RFM） and rigorous sensor models （RSM）. For ortho-rectifying an image set, a rigorous sen- sor model-Toutin＇s model was employed and a set of reported parameters including across track angle, along track angle, IFOV, altitude, period, eccentricity and orbit inclination were input, then, the orbit calculation was started and the track information was given to the raw data. The images were ortho-rectified with geocoded ASTER images and digital elevation （DEM） data. Results showed that with 16 ground control points （GCPs）, the correction accuracy decreased with view zenith angle, and the RMSE value increased to be over one pixel at 36 degree off-nadir. When the GCPs were approximately chosen as in Toutin＇s model, a RFM with three coefficients produced the same accuracy trend versus view zenith angle while the RMSEs for all angles were improved and within about one pixel.     

关于城市浅山区生态廊道景观规划的探索——张家口市城市快速路景观设计

运用生态学基本原理和方法,结合绿道理论,从整个区域的生态、游憩、文化、美学及土地的可持续发展相关概念、多重目的进行快速路景观设计,着力体现"城市大园林"构想,建设城乡一体化的绿地体系,针对公路建设与生态建设同步实施课题进行有益的探索。     

公路工程监理的几点体会

本文对公路工程监理中的工程质量、工程进度、工程费用三大目标的控制进行了较为系统的分析和论述。