鸡西市重拳严打非法盗采

本报讯 日前,鸡西市政府组织国土资源局、公安、国保大队、煤炭、安监等相关部门对全市重点地区非法开采、盗采小煤井行为进行了专项整治,共填埋炸毁各类非法开采小井口30余处,拘留40余人,依法扣押运输车辆一台、提升设备一台、电镐7把、电缆560米。     

公共设施区位理论及其相关研究述评

公共设施科学配置、合理布局、实现效率与公平最大化是保障社会健康发展的基础,公共设施区位理论深受地理学、城市规划、经济学等各领域学者的广泛关注.已有综述类研究缺乏对公共设施区位相关理论体系的全面探讨,同时对20世纪90年代中后期以来的相关研究进展关注较少.本文一方面通过将公共设施区位理论与传统区位论在区位选择目标、决策主体、理论基础、研究内容等方面进行对比,对公共设施区位相关理论予以归纳;另一方面首先基于Deverteuil的综述研究简要阐述创始阶段、数量、后数最时代西方公共设施区位理论的研究内容、研究方法、理论依据及局限性,尔后从多设施、多目标复杂区位模型、空间可达性度量、规划决策支持系统等角度重点评述90年代中后期以来西方最新研究进展,同时对国内公共设施区位相关研究进展予以简要介绍;最后在厘清公共设施区位理论发展脉络的基础上,本文从统筹城乡公共设施配置、多种设施协同布局、区位决策因子多元化等方面提出未来研究展望.     

广州市运输型物流企业空间分布特征分析

基于广州市3 040个运输型物流企业的空间属性资料,揭示广州市运输型物流企业的空间分布规律,剖析不同区域运输型物流企业的集聚机理。研究表明:①全市运输型物流企业空间分布特征是中心城区高度聚集、其它地区零散分布,呈现"三心一轴"的格局。②各个区域呈现不同分布格局,白云区是三纵一横一个中心,越秀区是均质分布,荔湾区和海珠区是零散分布,天河区是轴线分布基础上的小规模集聚,黄埔区、萝岗区是双集聚中心。③影响各区域分布格局的主要因素有:城区历史因素(地理位置、经济发展水平),交通基础设施因素(城市主干道),经济活动中心因素(商业、商务、工业园区),物流节点因素(机场、货运站场、批发市场),规划政策(物流规划)因素和土地因素。     

农业资源利用效率的重新诠释与评价——以江苏省常熟市和江西省泰和县为例

本文重新诠释了农业资源利用效率的内涵,并建立一个新的农业资源利用效率评价框架和指标体系,以此完善和发展农业资源利用效率评价的理论与方法。论文选用多因素综合评价公式测算了常熟市与泰和县的农业资源利用生产率,运用包络分析法(DEA)计算了常熟市与泰和县的粮食生产配置效率。研究表明：①农业资源利用效率可以分解为农业资源利用生产率和生产配置效率两部分,生产配置效率又可进一步分解为纯技术效率和规模效率;②常熟市与泰和县的农业资源利用效率评价分值分别为0.967和0.984,农业资源利用生产率评价分值分别为0.953和0.922,生产配置效率分别为0.684和0.733;③常熟市粮食生产配置效率略低于泰和县,主要原因是常熟市粮食生产资源投入的冗余度(劳动、化肥、资本投入的冗余度分别为28.36%、23.45%和20.48%)高于泰和县(劳动、化肥、资本投入的冗余度分别为8.84%、8.83%和10.58%);④农业资源利用生产率的高低并不总与生产配置效率一致,农业资源利用效率评价应能兼顾这两者。     

黄河入海悬沙季节输送变化与输送机制的数值研究(英文)

Based on sediment and discharge flux data for the Yellow River, realistic forcing fields and bathymetry of the Bohai Sea, a suspended sediment transport module is driven by a wave-current coupled model to research seasonal variations and mechanisms of suspended load transport to the Bohai Sea. It could be concluded that surface sediment concentration indicates a distinct spatial distribution characteristic that varies seasonally in the Bohai Sea. Sediment concentration is rather high near the Yellow River estuary, seasonal variations of which are controlled by quantity of sediment from the Yellow River, suspended sediment concentration reaches its maximum during summer and fall. Furthermore, sediment concentration decreases rapidly in other seas far from the Yellow River estuary and maintains a very low level in the center of the Bohai Sea, and is dominated by seasonal variations of climatology wind field in the Bohai Sea. Only a small amount of sediments imported from the Yellow River are delivered northwestward to the southern coast of the Bohai Bay. Majority of sediments are transported southeastward to the Laizhou Bay, where sediments are continuously delivered into the center of the Bohai Sea in a northeastward direction, and part of them are transported eastward alongshore through the Bohai Strait. 69% of sediments from the Yellow River are deposited near the river delta, 31% conveyed seaward, within which, 4% exported to the northern Yellow Sea through the Bohai Strait. Wind wave is the most essential contributor to seasonal variations of sediment concentration in the Bohai Sea, and the contribution of tidal currents is also significant in shallow waters when wind speed is low.     

1997-2007年中国建设用地在经济增长中的利用效率

中国建设用地面积与经济同步增长,但也存在低效利用的问题.本文应用数据包络分析面向投入的CCR模型,测算得到了1997-2007年28个省份的资本、劳动和建设用地投入对GDP产出的效率.研究表明:①多数省份的建设用地等要素投入平均效率较低,各地区效率水平基本上与其经济发展水平一致;②以1997-2002年和2003-2007年两个时间段分别计算平均效率,有21个省份后一时段的效率相对降低,这个趋势与后一时段中国重化工业加速发展的趋势相吻合;③在资本、劳动和建设用地投入方面,存在不同形式的投入要素的松弛,即纯超量投入,主要以就业人口和建设用地的松弛为主,进一步表明这些生产要素没有实现最佳配置.     

黄河入海泥沙悬移输送机制的控制试验(英文)

Five diagnostic experiments with a 3D baroclinic hydrodynamic and sediment transport model ECOMSED in couple with the third generation wave model SWAN and the Grant-Madsen bottom boundary layer model driven by the monthly sediment load of the Yellow River, were conducted to separately diagnose effects of different hydrodynamic factors on transport of suspended sediment discharged from the Yellow River in the Bohai Sea. Both transport and spatio-temporal distribution of suspended sediment concentration in the Bohai Sea were numerially simulated. It could be concluded that suspended sediment discharged from the Yellow River cannot be delivered in long distance under the condition of tidal current. Almost all of sediments from the Yellow River are deposited outside the delta under the condition of wind-driven current, and only very small of them are transported faraway. On the basis of wind forcing, sediments from the Yellow River are mainly transported north-northwestward, and others which are first delivered to the Laizhou Bay are continuously moved northward. An obvious 3D structure characteristic of sediment transport is produced in the wind-driven and tide-induced residual circulation condition. Transport patterns at all layers are generally consistent with circulation structure, but there is apparent deviation between the depth-averaged sediment flux and the circulation structure. The phase of temporal variation of sediment concentration is consistent with that of the bottom shear stress, both of which are proved to have a ten-day cycle in wave and current condition.     

Sediment removal efficiency of siphon dredging with wedge-type suction head and float tank

Siphon dredging with a float tank and different siphon suction heads, including the plain-type and wedge-type with/without side holes, through flume experiments were used to investigate the reservoir sediment removal efficiency. The experiment revealed maximum suction pressure and velocity when the distance from the suction head to the bed was about 25% of suction head diameter. Suction pressure decreased rapidly as the distance from the suction head to the bed increased to 50% and 100% of suction head diameter. Suction pressure achieved by wedge-type suction head was only 16.9-17.6% of that around plain-type suction head, and the velocity around wedge-type suction head was 64.7-68.4% of that around plain-type suction head. However the plain-type suction head was easily clogged doe to its long bobbing period. The average bobbing period for the plain-type suction head was about 105-263% that of the wedge-type suction head. The sediment removal efficiency was achieved when float tank diameter was 3-4 times that of the suction head. Flow discharge and sediment removal increased as the suction head diameter and side hole diameter increased, respectively. The most efficient side hole area was an area within 15% of suction head area. Totally, the optimal sediment removal efficiency was the wedge angle of 20° with 3 side holes. The efficiency of sediment dredging by siphon suction with a suction tube passing through the dam bottom was better than that with suction passing over the top of the dam. The wedge-type siphon suction with a float tank is preferable for sediment dredging in small reservoirs because it is inexpensive and efficient.     

江苏省能源效率空间分异特征与成因分析

提高能源效率是江苏省突破能源困局的重要途径。文章采用数据包络分析法(Data Envelopment Analysis, DEA),在全要素生产力分析框架下,测度2007 年江苏省各地级市能源利用的综合效率、技术效率和规模效率,分析3 类能源效率的空间分异特征,并根据3 类能源效率的关联关系划分能源效率的地域类型;进而采用变异系数(CV)、单位GDP能耗和大中型 企业集中指数(CI) 等指标,结合各地级市的产业结构特征,分析江苏省能源效率地域分异成因;最后,根据DEA模型的投入产出优化目标值(Targets),探讨提高各地级市能源效率的对策措施。研究结果表明：① 江苏省能源效率总体上呈南高北低、东西分化的分布特征,并存 在轻工业型和重工业型两大“DEA有效”极核;② 能源规模效率是制约江苏省能源综合效率的主要方面;③ 单位GDP能耗可以集中反映区域能源技术效率水平,大中型企业集中指数可以集中反映区域能源规模效率水平;④ 高耗能产业比重高的区域其能源技术效率相对较低, 居于经济区过渡地带或边缘区位的区域其能源规模效率相对较低;⑤ 全省普遍存在生产要素投入冗余现象,可通过优化投资环境、产业结构高级化、突出特色产业、提升产业技术、提高劳动力素质及提高产业集中程度等途径来提高区域的能源利用效率。