自然资源开发利用度预警分析

本文分析了建立自然资源开发利用预警的必要性,研究了预警系统和预警流程。提出了预警建立的原则和相应的指标体系     

贵州喀斯特地区旅游资源的变异与可持续利用

喀斯特景观与民族文化是不可再生的旅游资源,其开发在促进喀斯特地区经济、文化发展的同时,也加剧了环境的损耗和地方特色的消失,旅游资源变异现象普遍发生。文中分析了资源变异的几种情况,并指出控制资源变异,实现可持续利用的途径     

Planning for cooler cities: a plan quality evaluation for Urban Heat Island consideration

ABSTRACT

City strategic plans and enabling policies provide a framework for and inform future development across multiple scales. An exemplar city strategic plan will be one based on evidence, enabled by complementary policy outcomes, and built on the knowledge of the existing landscape. This study evaluated the plan quality of eighteen metropolitan strategic plans for city members in the 100 Resilient Cities initiative. A protocol was developed containing thirty-two indicators to assess plans capacity to act as a strategic planning tool to develop, analyse and implement strategies for the Urban Heat Island (UHI) and climate change mitigation and adaptation. The evaluation indicated that strategies addressing the UHI are rarely included in metropolitan plans. Strategic plans showed a lack of evidence-base to inform the potential actions. Urban warming is often linked to extreme weather events anticipated under climate change, not the UHI as a systemic and increasing phenomenon. We recommend that the pathway to addressing UHI mitigation and adaptation may lie in its nexus to aspects of climate change that concurrently can serve to support liveable and resilient cities.     

Energy consumption estimation model for dual-motor electric vehicles based on multiple linear regression

ABSTRACT

The drive range of electric vehicle (EV) is one of the major limitations that impedes its universalism. A great deal of research has been devoted to drive range improvement of EV, an accurate and efficiency energy consumption estimation plays a crucial role in these researches. However, the majority of EV’s energy consumption estimation models are based on single motor EV, these models are not suitable for dual-motor EVs, which are composed of more complex transmission mechanisms and multiple operating modes. Thus, an energy consumption estimation model for dual-motor EV is proposed to estimate battery power. This article focuses on studying the operating modes and system efficiency in each operating mode. The limitation of working area of each mode ensures the vehicle dynamic performance, then PSO algorithm is adopted to optimize the torque (speed) distribution between two motors to improve the system efficiency in the coupled driving mode. Finally, the energy consumption estimation model is established by multiple linear regression (MLR). The result shows that the proposed model has a high precision in energy consumption estimation of dual-motor EV.     

Experimental study on the effect of fly ash content in cemented paste backfill on its anti-sulfate erosion

ABSTRACT

In order to study the effect of fly ash content in cemented paste backfill (CPB) on its anti-sulfate erosion, the apparent phenomenon, strength development, and hydration products change the law of CPB with different fly ash content under long-term soaking of 5% sodium sulfate solution were studied by the macrotest and microanalysis, in addition, the mechanism of CPB anti-sulfate attack was analyzed by combining with a scanning electron microscope (SEM). The results indicated that the effect of sulfate environment on the strength of fly ash cemented paste backfill (FCPB) was mainly determined by the hydration products in the FCPB at different soaking times. In the early soaking stage, the formation of ettringite (AFt) in FCPB could improve its compactness, which was conducive to improving the strength of FCPB. In the late soaking stage, there were ettringite-type erosion damage and gypsum erosion-type damage internal of the FCPB with low content fly ash, resulting in microfracture, cracking of the FCPB, and reducing the strength. CPB with an appropriate content of fly ash could improve the internal structure of the FCPB to achieve the purpose of anti-sulfate erosion.     

Preferred surface microscopic geometric features on floors as potential interventions for slip and fall accidents on liquid contaminated surfaces

PROBLEM: Surface roughness affects friction, so selection of floor surfaces with certain roughness characteristics could potentially reduce slip and fall accidents. This article summarizes the preferred surface microscopic geometric features that could increase friction on surfaces covered with liquid contaminants. METHOD: Three types of surface features, represented by the average of the maximum height above the mean line in each cut-off length (R(pm)), the arithmetical average of surface slope (Delta(a)), and the kernel roughness depth (R(k)), are identified as preferred surface microscopic geometric features for a higher friction. The proper settings on the profilometers (instruments used to measure surface roughness) for optimizing these surface parameters are specified. The friction mechanisms involved reveal why these features are more desirable. RESULTS: Although surface roughness is important in determining slipperiness, there is still insufficient information to establish a safety criterion based on roughness; however, the method presented in this paper can readily provide a relative comparison. IMPACT ON INDUSTRY: The summary presented will help safety professionals properly select new floor surfaces or assess existing floors to reduce slip and fall accidents.     

Utilization of Photographs for Determining Impact Indicators for Trail Management

Indicators are a key component of resource management, but selecting them can be difficult and controversial. This study explores different methods for selecting impact indicators for management of trail conditions by comparing photo survey methods (PSM) with written survey methods (WSM). A total of 661 subjects participated in interviews conducted within Mudeung- Mountain Provincial Park in Kwang-ju, Korea. PSM explained variation in acceptability better than WSM. Six major photo components (in order of importance: area of large rocks on trail, area of wood steps, area of bare roots, area of bare soil, area of small stones, and area of stone steps) explained 84.7% of the variation in acceptability of trail management conditions. This study suggests that PSM can be a useful tool for selecting impact indicators. Supported by the grant of Post-Doctoral Program, Chonbuk National University (2001)     

Removal of copper ions and dissolved phenol from water using micellar-enhanced ultrafiltration with mixed surfactants

A laboratory study was conducted to evaluate the effects of composition and concentration of mixed anionic/nonionic surfactants on the efficiency of a micellar-enhanced ultrafiltration (MEUF) operation in removing metal ions/organic solutes from aqueous solutions. Based on the analysis of surface tensions and micelle sizes, it was found that for mixed sodium dodecylsulfate (SDS)/Triton X-100 surfactants, the critical micelle concentration (cmc) was significantly lower than that of SDS and mixed micelles formed. The mixed surfactant system was then applied in a cross-flow mode of MEUF, in which the concentration polarization can be neglected, to remove Cu2+ from aqueous solutions. With a surfactant concentration of 10 mM, the Cu2+ rejection was negligible by using pure Triton X-100 and increased with increasing SDS mole fraction with a value as high as 85%, which suggests that the rejection of Cu2+ was due to the electrostatic attraction between Cu2+ and SDS. Furthermore, pronounced Cu2+ rejection was obtained for a 5 mM SDS solution, which was attributable to a decrease in the cmc of SDS by the existence of Cu2+. When the MEUF technique was applied to remove Cu2+ and phenol simultaneously from aqueous solutions, the Cu2+ rejection was slightly enhanced in the presence of phenol. However, the rejection of phenol was comparatively low, approximately 27%, which may be caused by its relatively hydrophilic characteristic.     

废钻井液固化实验研究

利用经实验筛选的固化剂配方对废钻井液进行了固化处理的室内配方研究。结果表明,经该固化剂配方处理后的固结材料在水中浸泡5d后的浸出液在色度、化学需氧量、pH值、石油类、悬浮物含量和重金属含量等指标方面可达到国家《污水综合排放标准》(GB8978-1996)中的二级标准。     

国内外油田含油污泥处理技术

通过对国内外各种含油污泥处理工艺技术的调查分析和对比,提出了适合国内实际的含油污泥处理技术方案。以离心分离技术为核心,辅之以调质、倾析等多种预处理技术和高温裂解、生物处理等后续处理技术的污泥综合处理工艺,适于我国现阶段的含油污泥处理。