乡村公路建渣路面结构经济性和环保性研究

针对川南地区高水量粉质粘土软弱路基的情况,提出一种以建渣代替片石、碎石的建渣路面结构形式,通过现场试验对建渣路面结构和传统路面结构的经济性能进行了定量的分析比较,结果表明建渣路面结构具有良好的经济性能和环保性能。     

乡村公路建渣路面结构的技术性能研究

针对川南地区高水量粉质粘土的情况,从再生骨料强度、各层配合比及粒径要求、弯沉值等方面出发,分析了建渣路面结构技术性能,并将其与传统路面结构施工工期进行了研究比较,指出乡村公路建渣路面的结构性能、施工工期较传统路面结构有一定的优势。     

新时期农村公路建养体制的问题与对策

在分析农村公路建养现状及存在问题的基础上,从健全农村公路养护管理体制、推进农村公路养护生产市场化、建立多元筹资模式等方面,探讨了农村公路建养体制改进措施,以使农村公路养护工作更加规范。     

Changes in farming system and population as drivers of land cover and landscape dynamics: The case of enclosed and semi-openfield systems in Northern Galicia (Spain)

In this study, we aimed to document the changes in the bocage and semi-openfield landscapes of Northern Galicia from the second half of the 20th century and analyse the factors driving landscape changes. In particular, we examined (1) the dynamics of the field systems characteristics in these landscapes and (2) the interrelations with changes in dominant land cover, population and farming systems (in terms of productive structure, land use system and farming practices) dynamics. The picture of the1950s showed mainly semi-openfield field systems and nucleated villages that extended through valleys in the lowland, with banks in rough coastline sectors. In the highlands we found enclosed fields and scattered hamlets interspersed within large extensions of scrubland. In between both systems, a transitional area with mixed characteristics appeared. In 2000, the transitional area expanded from the former semi-openfields and banks areas, while the highlands still retain the enclosed character. The dominant land cover has experienced significant changes throughout the area, following an increase in woodland. A reorientation of the farming system was observed, a shift in which cropland lost importance with regard to grassland, the use of scrubland became marginal and forestry increased. The decrease in the number of farms and livestock shows decline in agricultural activity. This can be closely related to changes in dominant land cover and cropping patterns. Despite recent changes, this area still retains characteristic features of traditional landscapes such as the spatial pattern of field systems and ancestral cultural practices (e.g. extensive grazing of the scrubland).     

以宜川县为例谈县域城乡统筹发展研究

在分析统筹城乡发展研究的基础上,总结了宜川城乡发展现状和存在的问题,探讨了宜川县城乡统筹规划的目标、重点内容及编制的方法等,指出城乡统筹规划是协调县域经济社会发展的主要途径,是解决其＂城乡对立＂和＂三农＂问题的关键。     

西部农村公路现状调查及问题浅析

通过对成高公路部分路段交通量的统计,分发相关的调查问卷,对其中的数据和事故隐患进行了分析,并提出了相关的改进意见,从而有效降低该路段的交通事故发生率。     

The Landscape Inventory of Galicia (NW Spain): GIS-web and public participation for landscape planning

The European Landscape Convention recognises the importance of public participation for landscape planning in order to capture local knowledge, sensitive issues and conflicts, boost exchanges of information and democratise the process. However, traditional public participation methods are frequently restricted to public exposure at the final stage of the planning process. New public participation movements call for a greater role for the people at all stages. The growing development of ICT and geospatial information technologies provides new means of improving the participation process. This paper describes the public participation procedure and the participation geographic information system used to develop the Landscape Inventory of Galicia, whose results were used for the characterisation of landscape types, the delimitation of special interest areas from the locations identified by citizens and the definition of special attention areas from the degraded areas located by population.     

Venture capital: The effect of local and global social ties on firm performance

Firm financing literature has been dominated by a relatively ‘undersocialized’ and ‘aspatial’ view. We approach this gap by applying a social capital and economic geography informed lens to financial transactions. We explore if and how the early growth performance of venture capital backed organizations varies with the structural and physical location of their investors in syndication networks. Drawing on longitudinal data of Belgian firms and their venture capital investors, it is demonstrated that inter‐firm relational ties and, especially cross‐border linkages expand organizational outcome. In that, we show that not only social relations shape financial activity, but that also spatial patterns of co‐investment networks deserve notice.     

Understanding the impact of risks on performance in internal and outsourced information technology projects: The role of strategic importance

Successfully managing the risks of information technology projects continues to be a central problem for organizations regardless of whether the project is outsourced or not. While a plethora of studies has examined the effects of risks on performance, majority fail to distinguish the sourcing characteristics of the projects investigated. Furthermore, little is known about the joint effects of strategic importance and the risk on system performance across internal and outsourced projects. Based on data collected from 77 internal projects and 51 outsourced projects, we find that social subsystem and project management risks are negatively associated with system performance in both internal and outsourced projects. However, technical subsystem risk negatively affects performance only in internal projects. While social subsystem risk exerts greater influence on system performance in outsourced projects than in internal projects, the technical subsystem risk has greater effect on performance in internal than that in outsourced projects. Moreover, the effect of project management risk is not different in both types of projects. In addition, strategic importance moderates the relationship between risks and performance. The negative impact of risks on performance is greater in projects that are more strategic. Strategies are proposed to reduce the complexity and potential conflicts inherent to strategic projects because these characteristics may amplify a risk's impact.     

加快推进重庆城镇化建设策略研究——基于重庆统筹城乡发展的视角

大城市、大农村、大山区和大库区并存使重庆成为全国城乡二元结构矛盾较为典型的地区。要打破这种城乡二元分割格局、解决农村问题,就必须城乡统筹考虑,加快城镇化进程。文章在分析直辖后重庆城镇化建设的主要绩效和存在问题的基础上,提出了新时期推进重庆城镇化进程的建议。     

Spatial and temporal trends of volatile organic compounds (VOC) in a rural area of northern Spain

Ambient concentrations of volatile organic compounds (VOCs) were measured at 40 rural sampling points in Navarre (northern Spain). Air samples were collected by means of sorbent passive sampling and analyzed by thermal desorption (TD) and gas chromatography/mass-selective detector (GC/MSD). A total of 140 VOCs were identified during the study, which was carried out between May to October 2004 for a total of a 10 biweekly sampling campaigns. Concentrations of benzene, toluene, ethylbenzene, m/p-xylenes, o-xylene (BTEX) and 1,3,5-trimethylbenzene were determined in order to investigate their temporal and spatial distributions. Geostatistical analysis pointed to traffic as the main emission source of these compounds. Supporting this idea, BTEX and nitrogen oxides concentrations were found to be highly significantly correlated (r = 0.495, P = 0.001), whereas a strong negative correlation between BTEX and ozone was also observed (r = -0.355, P = 0.025). The concentrations for the BTEX group were similar to the values that have been previously reported for other rural areas.     

新形势下城乡规划专业本科教育的改革与探索——解析天津大学城乡规划专业新版本科培养方案

针对城镇化发展的新常态对城乡规划专业人才的需要,以及城乡规划一级学科教育的目标,文章分析了当前城乡规划专业本科教育面临的发展机会和挑战,并以天津大学城乡规划专业本科培养方案的修订为例,探讨城乡规划专业本科教育改革。通过对原版培养方案的解析,对比介绍了新版培养方案的改革思路、办学思想、培养目标等概况,重点阐述了新版培养方案在教学安排、课程组织和教学方法上的探索与尝试。     

The potential impacts of sprawl on farmland in Northeast China—Evaluating a new strategy for rural development

China's “building a new countryside” strategy for coordinating urban and rural development and gearing up national economic growth brings challenges to the country's farmland protection. The objective of this study is to evaluate potential impacts of implementing the strategy on farmland and to provide scientific guidelines and decision support for decision makers in northeast China. We analyzed three “building a new countryside” implementation scenarios (Historical Trend, Intensive Development, and Extensive Development) using the SLEUTH urban growth and land cover change model in combination with remote sensing and GIS analysis. The results indicated that farmland loss was inevitable, but revealed large differences in landscape patterns and the amount of farmland loss among the three BNC implementation scenarios. The Extensive Development scenario showed the largest increase in urban and rural residential land, the highest level of landscape fragmentation, and the largest loss of farmland. Farmland loss under the Intensive Development scenario is higher than that under the Historical Trend scenario; however, urban and rural sprawl and the fragmentation of landscape under the Intensive Development scenario were lower than those under the Historical Trend scenario. Consequently, the Intensive Development scenario was recommended for actual “building a new countryside” implementation in the study area. Potential rural sprawl under the Intensive Development scenario was also discussed, which provided useful information for guiding scientific-based decision support and policy making. While most studies of sprawl prediction involve urban centers only, our study presents a case of predicting urban and rural sprawl simultaneously.     

新形势下地方高校城乡规划专业特色办学路径探索——以安徽建筑大学为例

随着城镇化进程加快和城乡规划学科的发展,开办城乡规划专业的地方高校越来越多,办学竞争日趋激烈,如何寻求特色化发展已成为地方高校城乡规划专业发展的热点问题。文章分析了地方高校城乡规划专业办学面临的新形势,以安徽建筑大学为例,从特色凝练、课程优化、就业导向3个方面探讨新形势下地方高校城乡规划专业特色办学路径,以期实现发展创新力、提升竞争力及扩大影响力的目标。     

Evaluation of distribution, mobility and binding behaviour of heavy metals in surficial sediments of Louro River (Galicia, Spain) using chemometric analysis: a case study

Contents of total and extractable heavy metals, carbonates, MnO and Fe₂O₃, organic matter, and matrix components such as SiO₂, Al₂O₃, CaO, Na₂O, MgO, TiO₂, K₂O and P₂O₅ are used along with principal component analysis (PCA) for studying distribution, mobility and binding behaviour of Cd, Cr, Cu, Ni and Pb in the Louro River (Galicia, Spain). Eleven surficial sediment samples were taken along the beds of the river course. Total metal concentrations were obtained after microwave-assisted digestion whilst extractable metal contents were obtained following a three-stage sequential extraction scheme (i.e. soluble, reducible and oxidisable fractions). Loading plots of heavy metals bound to carbonates, Fe–Mn oxides, organic matter and aluminosilicates allowed determination of binding behaviour. Correlations found indicate that Pb and Cu are mainly discharged from urban wastes, whereas Cr and Ni are from electroplating and galvanizing industries. The occurrence of diffuse pollution sources along the river can account for the binding behaviour of Cd. Metal mobility decreased in the order: Cd>Pb>Cu>Ni>Cr. Despite total contents indicating moderate-to-high heavy metal pollution in this river, metals are mostly distributed in the residual fraction, hence showing a low risk of mobility.     

Team development and performance in construction design teams: an assessment of a hierarchical model with mediating effect of compensation

A high-performance construction workplace invests in its human resources and facilitates their technical and innovation skills through team development. Though team development has been explored in many studies, to date, little research has disentangled how team development and compensation methods enhance team performance in construction companies. Accordingly, team development as a hierarchical, reflective construct, incorporating six associated components was extended and the variables of the model in a nomological network analysed using partial least squares (PLS). As a result, with the help of PLS path modelling, a hierarchical team development construct with the mediating effects of compensation on the relationship between team development and team performance was developed. The research analysis was completed on a sample population of 128 construction design teams and the results lead to the development of a model that shows team development has a significant direct and indirect impact on team performance. The results also confirm the mediating role of group compensation on the relationship between team development and team performance. In general, it is suggested that the design teams achieved better performance when the leaders adapted team compensation methods consistent with the team development practices.     

Prospects of non-edible neem (Azadirachta indica) oil in Bangladesh: performance and emission evaluation in a direct injection diesel engine

Transition to alternative energy is receiving serious attention globally and in this very way, biodiesel from inedible neem can be an alternative to conventional liquid fuels as it contains 30–45%?wt of oil. In this study, esterification and transesterification reaction of methanol and triglycerides at a molar ratio of 7:1 was done and maximum 96% by volume biodiesel was extracted. Physiochemical properties of neem biodiesel lies within ASTM standards and Fourier transform infrared spectroscopy analysis of neem biodiesel reveals the presence of strong esters and the alkane group. The maximum efficiencies were found to be 22.8% and 22.3%, whereas minimum brake specific fuel consumptions were observed to be 0.57 and 0.59?kg/kW-hr for diesel and B20, respectively. Moreover, B20 provides less emission of HC, CO_x and increase in NO_x. Taking all into consideration, if at least 60% of the arid lands is utilised to cultivate neem trees then it will minimise the import of fossil fuel to an extent of 8.75%.     

The impact of a call centre on communication in a programme and its projects

Call centres are increasingly being utilised in public sector programmes to facilitate and manage communication between numerous stakeholders. Yet, the impact of call centres on projects has not been investigated. This paper reports on a survey with 92 respondents that assessed the impact of a call centre for a repair and maintenance programme. An empirically verified model is presented to illustrate the relationship between call centre communication and project performance. A balance of frequent informal and formal communication is shown to reduce mistrust and conflict of interest resulting from each party trying to maximise his respective economic position in the principal–agency relationship. The data provides evidence that a call centre improves the communication, collaboration and trust in project principal–agency relationships which, in turn, is perceived to contribute to project performance.     

Impact of nano zero valent iron (NZVI) on methanogenic activity and population dynamics in anaerobic digestion

Nano zero valent iron (NZVI), although being increasingly used for environmental remediation, has potential negative impact on methanogenesis in anaerobic digestion. In this study, NZVI (average size = 55 ± 11 nm) showed inhibition of methanogenesis due to its disruption of cell integrity. The inhibition was coincident with the fast hydrogen production and accumulation due to NZVI dissolution under anaerobic conditions. At the concentrations of 1 mM and above, NZVI reduced methane production by more than 20%. At the concentration of 30 mM, NZVI led to a significant increase in soluble COD (an indication of cell disruption) and volatile fatty acids in the mixed liquor along with an accumulation of H₂, resulting in a reduction of methane production by 69% (±4% [standard deviation]). By adding a specific methanogenesis inhibitor-sodium 2-bromoethanesulfonate (BES) to the anaerobic sludge containing 30 mM NZVI, the amount of H₂ produced was only 79% (±1%) of that with heat-killed sludge, indicating the occurrence of bacterially controlled hydrogen utilization processes. Quantitative PCR data was in accordance with the result of methanogenesis inhibition, as the level of methanogenic population (dominated by Methanosaeta) in the presence of 30 mM NZVI decreased significantly compared to that of the control. On the contrary, ZVI powder (average size <212 μm) at the same concentration (30 mM) increased methane production presumably due to hydrogenotrophic methanogenesis of hydrogen gas that was slowly released from the NZVI powder. While it is a known fact that NZVI disrupts cell membranes, which inhibited methanogenesis described herein, the results suggest that the rapid hydrogen production due to NZVI dissolution also contribute to methanogenesis inhibition and lead to bacterially controlled hydrogenotrophic processes.     

Importance and performance of streetscapes at a tourism destination in Indonesia: The residents' perspectives

The present study examined the importance and performance of streetscapes at a tourism destination in Makassar, Indonesia, from the residents’ perspectives using the importance–performance analysis method. Thus, six attributes of the streetscapes in four segments of the old city district were identified and presented to 400 participants. The participants were then asked to rate the perception and preference of each attribute. Results of the attribute values were illustrated in a Cartesian diagram. Findings indicate notable discrepancies between the perceptions and preferences of the respondents. Thus, these attributes were inconsistent with their expectations. Moreover, the results showed that each segment should have different priorities for specific attributes to improve the performance of the streetscapes. Overall, such data can be used by stakeholders, such as tourism developers and government policymakers, to make appropriate and informed decisions that will improve the attractiveness of this tourism destination and increase the number of visitors.