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运用信息熵理论研究条件估值调查中的抽样问题  [PDF]
系统工程理论与实践 , 2003,
Abstract: ?条件估值研究是当前国际上流行且唯一的衡量环境物品非利用经济价值的方法,其中样本的数量和问卷的设计是条件估值研究能否成功的关键因素之一.采用信息熵理论研究了恢复额济纳生态系统条件估值的最佳抽样样本容量问题,通过比较增加随机抽样样本容量所获得的边际信息和增发问卷的边际成本,结果发现,在黑河流域采用支付卡的条件估值研究方法,发放400份有效问卷就能相当近似地得到实证调查中发放646份有效问卷的结果.同时研究发现,被调查者的相关社会经济信息,不仅可以减少条件估值研究结果的不确定性,而且与列联表相关检验结合可以用来揭示被调查者支付意愿的差异.分析表明,在恢复额济纳生态系统的问卷调查中,被调查者的学历、收入、户籍和所居住的区域对支付意愿的结果有较大的影响,而被调查者的年龄和性别对支付意愿的影响很小.
The Characteristics of Ground Flashes in Beijing and Lanzhou Regions

Qie Xiushu,Guo Changming,Liu Xinsheng,

大气科学进展 , 1991,
Abstract: Over twenty thousand lightning location data obtained by using Lightning Location System (LLS) from Lanzhou and Beijing regions have been analysed to ascertain the characteristics of ground flashes in both regions. The strength of positive flashes is 5 times higher in Lanzhou than in Beijing. The strength of positive flashes is 3 times and 2.2 times as large as negative flashes in Beijing and in Lanzhou respectively. It has been found that the strength of positive and negative flashes is submitted to the normal distribution, and is independent of the characteristics of thunderstorm. So the lightning, strength obtained by DF may be used to forecast the coming of thunderstorm. Although the stroke number in both regions decreases as exponent regulation, the maximum number of return stroke for one lightning in Beijing is more than that in Lanzhou. The peak flash rate occurs in late afternoon for both regions, but the maximum and minimum flash rate appeared an hour earlier in Beijing than in Lanzhou.The relationship between DF display and lightning radiation electric field, discharge current is obtained.
兰州银滩湿地沉积物有机质源解析及色素对环境的指示 Organic matter sources in the Lanzhou Yintan wetland and pigments that can indicate relevant environments  [PDF]
张丽,Imbabazi Berthe,徐荣海,叶生霞,张成君
- , 2017,
Abstract: 分析了兰州银滩湿地沉积物中有机质饱和烃组分及色素,有机质来源,以及人类活动对湿地的影响、演化等.结果表明:饱和烃正构烷烃主要以双峰、前峰、后峰型为主,有机质主要来源于藻类、陆生植物和挺水植物,沉水植物和浮游植物有较小的贡献.湿地水体的营养化现象逐步加强,但水体中藻类的数量相对较低,主要为外源污水的毒性导致水质恶化
叶济蓉  [PDF]
叶济蓉?
中国科技期刊研究 , 2007,
Abstract: ×老师:您好!我是贵刊的忠实读者,也是近年来连续不断向贵刊投稿的忠实作者。虽然屡投屡败,但我没有丧失信心。因为虽然稿子被退,但我得到您宝贵的审稿意见,同时也得到了您对我热忱的鼓励。这使我在困境中鼓足勇气,找出失败的原因,不断进行写作尝试。在此,请允许我向您表达崇高的敬意和深深的感激。我也是一名编辑,我要以您为榜样,认真对待每一篇论文,真心对待每一位投稿的作者。…福建农林大学学报(自然科学版)编辑部叶济蓉2007-10-23350002福建金山福建农林大学
小议材料暂估入账  [PDF]
黄芳
财会月刊 , 2007,
Abstract:   材料暂估入账是指企业采购的材料已验收入库,而供应商发票等结算凭证尚未收到,月末按暂估价入账,到下月初再红字冲回。这种做法至少存在如下不足:①材料早已入库,却要到月末才暂估入账,导致账实不符。并且在材料已被领用或已销售的情况下,账实差异更大。②在材料品种多、收发频繁的单位,月末暂估入账、下月红字冲回的工作量很大,容易出错。③在实行计划成本核算的企业中,月末若按计划成本暂估入账,而成本差异却待收到发票后再确认,会导致发出材料的成本差异分摊滞后。针对上述问题,笔者根据多年的实践经验,提出以下建议:  1.将入库单财务联增加为颜色各异的两联,一联为暂估联(绿),一联为确认联(黄)。  2.材料入库后,仓库将两联财务联一起交给会计部门。会计人员将其与采购合同匹配后,抽取其中绿色暂估联,根据采购订单中规定的不含税单价,借记“原材料”科目,贷记“应付账款——应计暂估”科目(不含税金额),并在黄色确认联上注明此笔入账金额。特别提醒,暂估入账时,只需估计货价部分,无需估计增值税进项税额。
ENVIRONMENTAL PROBLEMS IN WESTERN PART OF YINTAN NATIONAL TOURISM AND HOLIDAY RESORT OF BEIHAI CITY
北海市银滩国家旅游度假区西区的环境问题

WU Yu,hua,
吴宇华

自然资源学报 , 1998,
Abstract: Yintan National Tourism and Holiday Resort, located on the seashore of Beihai City of Southwest China, is one of the twelve national tourism and holiday resorts approved by the State Council in October of 1992. It occupies an area of 22.15 km2 and is divided into western part and eastern part by Fengjia River. The western part covers 8.71 km2. From 1987 up to now, the western part of Beihai Yintan National Tourism and Holiday Resort has been attracting more than 8 million tourists. The tourism activities bring in environmental problems, namely, natural resources destruction, visual pollution, pollution of waste water and trash, sand quality degradation and tourist overload.(a)Natural resources have been seriously destroyed. A lot of trees were cut away and the lands was used for dense buildings. Part of the beach is occupied by blocks of villas and tourism facilities. A wave proof dike separates the spacious beach into two zones, making the width of the beach from more than a thousand meters to less than two hundred meters.When the tide is at flood, the west section of the beach is submerged to the foot of the dike,reducing the bathing function of the section.(b)Many villas, hotels and tourism facilities do not harmonize with surroundings in aspects of location and shape. The varied buildings in the bathing center are established just next to the dike, too near to the beach and the sea, disordering the landscape of the water front. Buildings in other places are also too dense.People there would think they were in a downtown city. The space and design style of the entrance square are a failure, and it can not attract visitors to stay in.(c)Sea water near the seashore is polluted by nitrogen, BOD5 and oil.(d)The beach is polluted by waste water and trash from local domestic lifes and tourism activities, and the sands bagan to change from white color to gray.(e)The west section of the beach is often overloaded by tourists, for they crowd there to get convenient service.Those problems are derived from the lack of natural resources survey, weakplanning, poor management and insufficient investment to environment. So corres pondingly, the survey and evaluation of natural resources should be done first followed by environment releted planning and its implementation. The key is master plan which should include contents of environmental capacity, environmental protection, landscape control, landuse allocation,and distribution of tourism attractions. Finally,environmental policies and management measures should also be formulated and put to practice.They should contain the following: restriction of types and scale of projects, collection of pollution tax from hotels and restaurants, control of vehicles and parking lots, announcement of the state of environment, stipulation of tourists, clean of trash, relocation of service stands.
广义系统稳态Kalman估值器  [PDF]
邓自立, 刘玉梅
自动化学报 , 1999,
Abstract: ?用现代时间序列分析方法,提出了广义离散线性随机系统稳态Kalman滤波、平滑和预报的一种统一格式,给出了稳态Kalman估值器增益新算法,避免了求解Riccati方程.为保证估值器的渐近稳定性,给出了选择初始估值的公式.仿真例子说明了所提出的结果的有效性.
动态系统白噪声估值器  [PDF]
邓自立, 周露, 刘叔军
自动化学报 , 1995,
Abstract: ?用现代时间序列分析方法提出了单输入单输出(SISO)动态系统的统一的和通用的白噪声估值器.它包括输入白噪声估值器和观测白噪声估值器,可处理非零均值白噪声、相关白噪声、不稳定和非最小相位系统.对于雷达跟踪系统的仿真例子说明了其有效性和可应用性.
Atmospheric particulate pollution of Lanzhou using magnetic measurements
Chen Fa-hu,Yang Li-ping,Wang Jian-min,Zhang Jia-wu,
Chen Fahu
,Yang Liping,Wang Jianmin,Zhang Jiawu

环境科学学报(英文版) , 1999,
Abstract: To differentiate between natural and anthropogenic particulate sources in the atmosphere in Lanzhou City, samples were collected in different sites. The dust flux was calculated and magnetic measurements were conducted. Results show a distinct pattern of variation of dust flux within a year and it agrees with the shifts of atmospheric circulation regime. The magnetic parameters indicate that natural sources are the major components of atmospheric particulate during late spring and early summer, while anthropogenic sources contribute much more during winter months. The data also support the earlier findings that magnetic parameters are effective for differentiating between particulate arising from natural sources such as soil erosion and from anthropogenic sources such as coal combustion.
暂估材料会计处理之我见  [PDF]
余念
财会月刊 , 2010,
Abstract: 计划成本法下暂估材料的会计处理直接影响到发出材料成本的核算。本文探讨了暂估材料成本差异的核算,通过分析其对当期发出材料成本的影响,认为现行暂估材料的会计处理比较符合实际。  【关键词】暂估材料会计处理材料成本差异率发出材料成本一、暂估材料现行会计处理方法  暂估材料是指企业购进的,到了月底料已入库而结算凭证未到,为保证会计核算的及时完整,在会计处理时按合同价或计划成本入账的材料。  《企业会计准则第1号——存货》第二章第四条规定,存货同时满足下列条件的,才能予以确认:①与该存货有关的经济利益很可能流入企业;②该存货的成本能够可靠计量。
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