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利用价格杠杆使农民多交售商品农产品
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作者 贤彬 《农业现代化研究》 1981年第2期49-49,共1页
1979年,桃源全县比1978年多交售商品粮2,386万斤,增加8.1%;多交售商品棉2.5万担,增加22.82%。据统计,超购加价使桃源县农民增加收入2350万元。其中:粮油超购加价收入金额640万元,为牌价收购金额的1.7倍;棉花超购加价交售4万担,虽只占... 1979年,桃源全县比1978年多交售商品粮2,386万斤,增加8.1%;多交售商品棉2.5万担,增加22.82%。据统计,超购加价使桃源县农民增加收入2350万元。其中:粮油超购加价收入金额640万元,为牌价收购金额的1.7倍;棉花超购加价交售4万担,虽只占牌价交售数的39.96%,但加价增收的金额却为牌价增收金额199万元的85.76%,这就从价格上鼓励了农民多卖商品农产品。 展开更多
关键词 超购加 利用价 农产品 商品粮 农民增 收入金额 多卖 商品棉 桃源县
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谨防三资企业利用价格手法转移利润
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作者 池达桂 《求实》 CSSCI 北大核心 1995年第4期31-32,共2页
谨防三资企业利用价格手法转移利润池达桂近些年来,在我国的经济生活中出现了一种奇怪的现象,即许多三资企业在帐面上表现为亏损或零利润,而其投资规模和生产规模却在不断地扩大。事实上,这些企业是盈利的,它们利用价格转移的方法... 谨防三资企业利用价格手法转移利润池达桂近些年来,在我国的经济生活中出现了一种奇怪的现象,即许多三资企业在帐面上表现为亏损或零利润,而其投资规模和生产规模却在不断地扩大。事实上,这些企业是盈利的,它们利用价格转移的方法把利润转移到了国外,使我国的经济和... 展开更多
关键词 格转移 跨国公司 三资企业 阿苯哒唑 利用价 关联公司 手法 中外合作企业 中外合资企业 转移利润
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加强藏书与流通工作 提高图书利用价值
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作者 周继 《辽宁农业职业技术学院学报》 1998年第1期74-75,共2页
高校图书馆历来是高校整体的一个不可分割的有机组成部分,是高校重要的教辅部门,在为学校多出人才、多出成果服务中起着不可替代的作用,因而各高校历来都十分重视图书馆的建设和管理。我校自1984年改建专科学校以来,在图书馆建设方面投... 高校图书馆历来是高校整体的一个不可分割的有机组成部分,是高校重要的教辅部门,在为学校多出人才、多出成果服务中起着不可替代的作用,因而各高校历来都十分重视图书馆的建设和管理。我校自1984年改建专科学校以来,在图书馆建设方面投入了很大的力量,现已形成藏书22万册,设施较齐全,结构较合理的新型图书馆。但近几年来, 展开更多
关键词 流通工作 高校图书馆 利用价 图书馆藏书 图书馆建设 图书馆工作 图书管理人员 院校图书馆 图书馆发展建设 新型图书馆
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别让价格左右你
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作者 小荣 《北京物价》 2000年第2期40-40,共1页
眼下,各商家为招揽顾客,掀起又一轮促销高潮,而在各种形式的促销活动中,无疑,商品降价是最具吸引力的.让我们看一看,商家是如何利用价格做文章的?
关键词 格游戏 商品降 招揽顾客 促销活动 刺激消费 成本计算 利用价 吸引力 产品质量 标高
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Ecological Suitability Evaluation on Agricultural Land in Western Jilin Province Based on Fuzzy Mathematics 被引量:2
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作者 臧立娟 王凤艳 任建超 《Agricultural Science & Technology》 CAS 2012年第8期1757-1761,共5页
[Objective] This study was to evaluate the ecological suitability of agricultural land in western Jilin Province, with the aim to provide basis for the effective application of agricultural resources and the structura... [Objective] This study was to evaluate the ecological suitability of agricultural land in western Jilin Province, with the aim to provide basis for the effective application of agricultural resources and the structural adjustment of land use. [Method] The evaluation index system was constructed based on fuzzy mathematic method according to the principles of systematic, dominant, effectiveness and feasibility; based on law of tolerance, reasonable evaluation criteria were determined according to the ecological amplitude of crops; based on GIS processing, the initial data completed the mathematical operation by using the VBA program in Excel. [Result] The area of agricultural land grade I was 5 512 km2, grade II of 25 985 km2, grade Ill of 7 907 km2, and area of land not suitable for agriculture was 6 312 km2. According to the evaluation results, the key areas for land use adjustment were Zhenlai County, Da'an County, Tongyu County and western Changling County. The directions of land use adjustment included improving irrigation and drainage conditions, governing land salinization and conversion of cropland to forest and grassland. [Conclusion] This study provided basis for the effective application of agricultural resources and ecological environment construction in western Jilin Province. 展开更多
关键词 Land use Suitability evaluation Agricultural land Fuzzy mathematic method Western Jilin Province
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Impacts of Land Use Change on Ecosystem Service Value in Yanchi County of Ningxia 被引量:3
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作者 杨越 孙保平 +3 位作者 哈斯 杜会石 赵岩 赵瑞 《Agricultural Science & Technology》 CAS 2013年第11期1687-1692,共6页
Based on TM image data in 1989, 1995, 1999, 2003, 2006 and 2009 of Yanchi County of Ningxia, the land use date of Yanchi County in each year were extracted supported by RS and GIS technology, and used to analyze the d... Based on TM image data in 1989, 1995, 1999, 2003, 2006 and 2009 of Yanchi County of Ningxia, the land use date of Yanchi County in each year were extracted supported by RS and GIS technology, and used to analyze the dynamic change of land use. The land use data were studied for estimating the change of ecosystem services value caused by the land use change of Yanchi County, using the evaluation method of China terrestrial ecosystem services value. The results showed that the changes of land use were obvious during 1989 to 2009. The area of woodland and construction land had an increasing tendency; grassland area changed from decreasing to increasing, which was in contrary to farmland and un-used land areas (from increasing to decreasing); water area fluctuated slightly. The ecosystem services value of Yanchi County had an increasing tendency during 1989 to 1995, because the increasing woodland area had took the major role in raising the total ecosystem services value. The grassland accounted for a large proportion of the total ecosystem service value of Yanchi County, with its contribution rate from 49.8% to 60.4%. And the composition of the ecosystem services value of Yanchi County happened benign change for the increasing contribution rate of woodland. The ecosystem services value sensitivity index of each land use type was less than 1, indicating that the ecosystem services value of Yanchi County lacks flexibility on its service value index, and the research results are reliable. 展开更多
关键词 Ecosystem services value Land use change Yanchi County of Ningxia
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Assessment of Direct Eco-value of Liangzi Lake
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作者 封瑛 李兆华 刘化吉 《Agricultural Science & Technology》 CAS 2013年第6期882-885,共4页
[Obective] This study amied to evaluate the direct usage value of Liangzi Lake, like plants and animal resources and water storage value. [Method] It was measured through the market value method. The physical environm... [Obective] This study amied to evaluate the direct usage value of Liangzi Lake, like plants and animal resources and water storage value. [Method] It was measured through the market value method. The physical environment was introduced and the productivity of the lake was investigated both through the literature materials and the investigations. The market value method was clarified in this paper as well as its operation process and the application fields. [Result] Based on the introduction of the current situation in Liangzi Lake, the direct usage value was estimated as 1.32 billion Yuan/year. Plant resources value was 318 million Yuan/year; animal resources value was 675 million Yuan/year; and water storage value was 325 million Yuan/year for the three parts. [Conclusion] This paper will attract more attention to the emphasis of the reasonable development of nature sources. 展开更多
关键词 Valuation assessment Direct usage value Market value method Liangzi Lake
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Response of Ecosystem Service Value Based on Land Use Changes and Analysis of its Driving Factors in Typical Hilly Region with Red Soil 被引量:6
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作者 邹金浪 王金政 +1 位作者 王鹏 乐文年 《Agricultural Science & Technology》 CAS 2010年第11期150-154,共5页
The contribution rate of ecosystem service value variation was used to analyze the effects of land use changes on the changes of ecosystem service value in Xingguo County during 1996-2005.Grey integrated correlation w... The contribution rate of ecosystem service value variation was used to analyze the effects of land use changes on the changes of ecosystem service value in Xingguo County during 1996-2005.Grey integrated correlation was employed to explore the contribution level of the indicators such as total population,urbanization level,proportion of primary industry and investment of social fixed assets on ecosystem service value,and the correlation analysis was also carried out.The results showed that the ecosystem service value in Xingguo County during 1996-2005 mainly was woodland,and the decrease of woodland area was the major reason for the sustained reduction of ecosystem service value.With the further increase of market demand and the incentives of local government,the garden area rapidly increased during 2001-2005,and the influence degree of garden towards the changes of ecosystem service value was only second to woodland,ranking No.2.Four socio-economic indicators had different correlation degree with ecosystem service value during the different research periods.Total population,urbanization level and proportion of primary industry had high correlation degree with ecosystem service value,whereas the influence degree of various socio-economic indicators on ecosystem service value was equal with each other day by day.Urbanization level,investment of social fixed assets and total population had significant negative correlation with ecosystem service value,while the proportion of primary industry had positive correlation with ecosystem service value. 展开更多
关键词 Ecosystem service value Land use change Gray correlation analysis Driving factor Hilly region with red soil
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Research on Evaluation and Optimization of Regional Land Use Structure Efficiency 被引量:1
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作者 张群 《Agricultural Science & Technology》 CAS 2016年第7期1749-1752,共4页
[Objective] The purpose of this study is to judge the rationality of land use structure from new perspectives and method. [Method] The theory of data en- velopment analysis (DEA) has been employed in this article. A... [Objective] The purpose of this study is to judge the rationality of land use structure from new perspectives and method. [Method] The theory of data en- velopment analysis (DEA) has been employed in this article. A case study of evalu- ation of land use structure for Wujin district in 2012 is provided to illustrate the ap- plication of this research model. At the micro perspective, land use efficiency has been analyzed by use of data envelopment analysis model. The optimization and adjustment direction in land use structure has been pointed out from the view point of land use efficiency. [Result] The result has shown that the research method based on information entropy and data envelopment analysis model can effectively overcome the drawback of traditional evaluation techniques. Compared with the tra- ditional methods, the new optimization model based on a structure of the multi-crite- ria factors and objective weighting method can evaluate the rationality of land use structure more comprehensively. 展开更多
关键词 Evaluation for efficiency Land use structure Data Envelopment Analysis
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新经济的政府困境
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作者 Lawrence H.Summers 胡菡菡 《商务周刊》 2002年第13期22-22,共1页
市场和技术变革远不能囊括经济进步的全部含义,当经济结构发生变化,政府职能也必须随之调整,否则发展的脚步就会停滞。 让我们先回到19世纪末的美国,正如Leon Trotsky所说的那样,“那里是锻造未来的火炉”。大工业生产,托拉斯,州际市场... 市场和技术变革远不能囊括经济进步的全部含义,当经济结构发生变化,政府职能也必须随之调整,否则发展的脚步就会停滞。 让我们先回到19世纪末的美国,正如Leon Trotsky所说的那样,“那里是锻造未来的火炉”。大工业生产,托拉斯,州际市场,庞大的电网,所有的一切都在新制度的孕育下诞生。原本一盘散沙的各州市场,在联邦法律的串联下变成了一个整体。 展开更多
关键词 政府困境 新经济 知识力量 反托拉斯法 经济进步 技术变革 利用价 火炉 新法规 新企业
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试论经济杠杆的运用
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作者 张鸿羽 《山西财经大学学报》 1985年第3期26-28,共3页
党的十二届三中全会《关于经济体制改革的决定》要求我们学会掌握经济杠杆,并且把领导经济工作的重点放到这一方面来。过去我国的计划管理,忽视了经济杠杆的作用,产生了许多弊端。随着计划体制的改革,指令性计划的范围和比重逐步缩小,... 党的十二届三中全会《关于经济体制改革的决定》要求我们学会掌握经济杠杆,并且把领导经济工作的重点放到这一方面来。过去我国的计划管理,忽视了经济杠杆的作用,产生了许多弊端。随着计划体制的改革,指令性计划的范围和比重逐步缩小,指导性计划、市场调节的范围和比重逐步扩大。在这种新形势下,计划工作就要来一个大的转变,必须学会和掌握经济调节手段的运用,使经济杠杆的综合运用成为国家计划的重要组成部分,使经济杠杆成为实现国家计划的有效手段。因此,正确认识和掌握经济杠杆的运用,无论在理论上和实践上都具有重要意义。也是当前摆在计划工作者面前的一项重要学习任务。 展开更多
关键词 经济杠杆 格杠杆 利用价 国家计划 通过税 计划工作 信贷 工资杠杆 国民收入 利息
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捍卫独创布图设计的专有权
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作者 王舜林 《软件和信息服务》 2015年第6期86-,共1页
捍卫集成电路独创布图设计的专有权,保护所有者权益,集成电路设计业才能健康发展。"钜锐案"的判决是我国集成电路知识产权保护的一个历史性的重大事件,对于集成电路布图设计侵权案的统一裁判尺度和法律适用标准以及促进集成... 捍卫集成电路独创布图设计的专有权,保护所有者权益,集成电路设计业才能健康发展。"钜锐案"的判决是我国集成电路知识产权保护的一个历史性的重大事件,对于集成电路布图设计侵权案的统一裁判尺度和法律适用标准以及促进集成电路技术创新和产业发展都具有重要意义,堪称经典性指导案例。一。 展开更多
关键词 布图 所有者权益 智力劳动成果 技术转让 代码信息 产权交易 曝光装置 保密协议 存储介质 利用价
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Group separation of coal components and new ideas of coal utilization as petroleum 被引量:19
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作者 QIN Zhi-hong HOU Cui-li CHEN Juan ZHANG Li-ying MA Jie-qiong 《Mining Science and Technology》 EI CAS 2009年第5期636-641,共6页
Four different groups of components were separated from coal under mild conditions of extraction and stripping process. Within these groups, and with pre-separation, individual utilization of all coal components can b... Four different groups of components were separated from coal under mild conditions of extraction and stripping process. Within these groups, and with pre-separation, individual utilization of all coal components can be realized, similar to petroleum components and enhance the inherent value and utilization value of coal, as well as increase environmental benefits. The characteristics of each component were analyzed with measurements by FTIR, GC/MS, TEM and the establishment of caking properties. The results show that coal can be separated into residues, ultra-pure coal, asphaltene components and light components by adding solvents for stripping into the CS2/NMP mixed extraction solution. Those four groups of components present great differences in the presence of carbon and hydrogen elements, in the structure of functional groups, in their macroscopic structure and micro-morphology and caking properties. Every component possesses its own inherent values and approaches. A new idea of coal processes and utilization, similar to the use of petroleum is proposed. 展开更多
关键词 COAL group components SEPARATION similarity to petroleum process and utilization
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Method for Evaluating the Degrees of Land Use Sustainability of Mountainous County and its Application in Yunnan Province,China 被引量:10
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作者 YANG Zisheng LIU Yansui +2 位作者 TAO Wenxing XU Jingling ZHAO Qiaogui 《Journal of Mountain Science》 SCIE CSCD 2008年第2期98-112,共15页
The evaluation of sustainable land use is the key issue in the field of studying the sustainable land utilization. In general analysis, the sustainable land use is evaluated respectively from its ecological sustainabi... The evaluation of sustainable land use is the key issue in the field of studying the sustainable land utilization. In general analysis, the sustainable land use is evaluated respectively from its ecological sustainability, economic sustainability and social sustainability in China and other countries in recent years. Although this evaluation is an important work, it seems insufficient and hard to comprehensively reflect the whole degree of land use sustainability. Thus, to make up this deficiency, this paper brings forward the evaluation indexes, which make it possible to quantitatively reflect the whole degree of land use sustainability, namely, the concept of "degrees of overall land use sustainability" (Dos), and research and measurement development of the method of and calculation in Dos. Taking the evaluation of the degree of land use sustainability in county regions of Yunnan Province as the actual example for analysis, results are basically as follows: 1) The degree of land use sustainability (Dos) is the ration index to organically and systematically integrate the degree of ecological friendliness (DeF), the degree of economic viability (Dev) and the degree of social acceptability (Dsa), able to comprehensively reflect the whole sustainability degree of regional land use 2) Based on the value of Dos, the grading system and standard for the sustainability of land use may be established and totally divided into five grades, namely, the high-degree sustainability, middle-degree sustainability, low-degree sustainability, conditional sustainability and non-sustainability. Meanwhile, the standard for distinguishing sustainability grades has also been confirmed so as to determine the nature of sustainability degrees in different grades. This makes the possibility for the combination of nature determination with ration in research result and provides with the scientific guideline and decision-making gist for better implementation of sustainable land use strategy. 3) The practice in evaluation of sustainability degree in county regional land use in Yunnan shows that the value of the degree of land use sustainability (Dos) of whole Yunnan Province is only 58.39, belonging to the grade of low-degree sustainability. Two thirds of counties in the whole province represent the grade of "conditional sustainability" and "non-sustainability" in the sustainability of land use. Among these counties, 11.11 % shows "non- sustainability'. The lowest degree of land use sustainability appears especially in the middle plateau mountain region of Northeast Yunnan, where the value of Dos in most counties (districts) is below 40 %, belonging to the grade of "non-sustainability". The sustainability degree in the karst mountainous region in lower-middle plateau mountain region in Southeast Yunnan is generally low and the value of sustainability degree (Dos) in most of the counties (cities and districts) is below 55. The value of sustainability degree (Dos) in most of the counties (cities and districts) in the north, west, northwest and southwest parts of Yunnan is below 55. This article also analyzes the reasons of low degree of sustainability in land use in Yunnan and puts forward the countermeasures to increase the degree of sustainability in land use in the whole province. 展开更多
关键词 Land use degrees of overall sustainability evaluation method county level degrees of ecological friendliness degrees of economic viability degrees of social acceptability
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Evaluation and prediction of blast induced ground vibration using support vector machine 被引量:14
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作者 KHANDELWAL M KANKAR P K HARSHA S P 《Mining Science and Technology》 EI CAS 2010年第1期64-70,共7页
We present the application of Support Vector Machine (SVM) for the prediction of blast induced ground vibration by taking into consideration of maximum charge per delay and distance between blast face to monitoring po... We present the application of Support Vector Machine (SVM) for the prediction of blast induced ground vibration by taking into consideration of maximum charge per delay and distance between blast face to monitoring point. To investigate the suitability of this approach, the predictions by SVM have been compared with conventional predictor equations. Blast vibration study was carried out at Magnesite mine of Pithoragarh, India. Total 170 blast vibrations data sets were recorded at different strate-gic and vulnerable locations in and around to mine. Out of 170 data sets, 150 were used for the training of the SVM network as well as to determine site constants of different conventional predictor equations, whereas, 20 new randomly selected data sets were used to compare the prediction capability of SVM network with conventional predictor equations. Results were compared based on Co-efficient of Determination (CoD) and Mean Absolute Error (MAE) between monitored and predicted values of Peak Particle Veloc-ity (PPV). It was found that SVM gives closer values of predicted PPV as compared to conventional predictor equations. The coef-ficient of determination between measured and predicted PPV by SVM was 0.955, whereas it was 0.262, 0.163, 0.337 and 0.232 by USBM, Langefors-Kihlstrom, Ambraseys-Hendron and Bureau of Indian Standard equations, respectively. The MAE for PPV was 11.13 by SVM, whereas it was 0.973, 1.088, 0.939 and 1.292 by USBM, Langefors-Kihlstrom, Ambraseys-Hendron and Bureau of Indian Standard equations respectively. 展开更多
关键词 blast vibration support vector machine generalised predictor equations
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Exploiting Geo-Social Correlations to Improve Pairwise Ranking for Point-of-Interest Recommendation 被引量:9
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作者 Rong Gao Jing Li +4 位作者 Bo Du Xuefei Li Jun Chang Chengfang Song Donghua Liu 《China Communications》 SCIE CSCD 2018年第7期180-201,共22页
Recently, as location-based social network(LBSN) rapidly grow, point-of-interest(POI) recommendation has become an important way to help people locate interesting places. Nowadays, there have been deep studies conduct... Recently, as location-based social network(LBSN) rapidly grow, point-of-interest(POI) recommendation has become an important way to help people locate interesting places. Nowadays, there have been deep studies conducted on the geographical and social influence in the point-of-interest recommendation model based on the rating prediction. The fact is, however, relying solely on the rating fails to reflect the user's preferences very accurately, because the users are most concerned with the list of ranked point-of-interests(POIs) on the actual output of recommender systems. In this paper, we propose a co-pairwise ranking model called Geo-Social Bayesian Personalized Ranking model(GSBPR), which is based on the pairwise ranking with the exploiting geo-social correlations by incorporating the method of ranking learning into the process of POI recommendation. In this model, we develop a novel BPR pairwise ranking assumption by injecting users' geo-social preference. Based on this assumption, the POI recommendation model is reformulated by a three-level joint pairwise ranking model. And the experimental results based on real datasets show that the proposed method in this paper enjoys better recommendation performance compared to other state-of-the-art POI recommendation models. 展开更多
关键词 location-based social network(LBSN)point-of-interest(POI)recommendation geographical influence social influence Bayesian personalized ranking(BPR)
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Evaluation of Intensive Urban Land Use Based on an Artificial Neural Network Model:A Case Study of Nanjing City,China 被引量:2
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作者 QIAO Weifeng GAO Junbo +3 位作者 LIU Yansui QIN Yueheng LU Cheng JI Qingqing 《Chinese Geographical Science》 SCIE CSCD 2017年第5期735-746,共12页
In this paper, the artificial neural network(ANN) model was used to evaluate the degree of intensive urban land use in Nanjing City, China. The construction and application of the ANN model took into account the compr... In this paper, the artificial neural network(ANN) model was used to evaluate the degree of intensive urban land use in Nanjing City, China. The construction and application of the ANN model took into account the comprehensive, spatial and complex nature of urban land use. Through a preliminary calculation of the degree of intensive land use of the sample area, representative sample area selection and using the back propagation neural network model to train, the intensive land use level of each evaluation unit is finally determined in the study area. Results show that the method can effectively correct the errors caused by the limitations of the model itself and the determination of the ideal value and weights when the multifactor comprehensive evaluation is used alone. The ANN model can make the evaluation results more objective and practical. The evaluation results show a tendency of decreasing land use intensity from the core urban area to the periphery and the industrial functional area has relatively low land use intensity compared with other functional areas. Based on the evaluation results, some suggestions are put forward, such as transforming the mode of urban spatial expansion, strengthening the integration and potential exploitation of the land in the urban built-up area, and strengthening the control of the construction intensity of protected areas. 展开更多
关键词 urban land intensive use functional area artificial neural network (ANN) model Nanjing City
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Humble View on Soil Water Resources 被引量:3
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作者 CHENZHI-XIONG ZHOULIU-ZONG 《Pedosphere》 SCIE CAS CSCD 1993年第3期261-268,共8页
Soil water is one of renewable water resources.Some properties of soil water concerning with its availability to plant are briefly described.An equation for estimating the amount of soil water resource is presented.Ba... Soil water is one of renewable water resources.Some properties of soil water concerning with its availability to plant are briefly described.An equation for estimating the amount of soil water resource is presented.Based on the evaporation demand of atmosphere,the evaluation coefficient for soil water resource is suggested. 展开更多
关键词 RESOURCE soil water
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SUSTAINABLE USE OF LAND RESOURCE AND ITS EVALUATION IN COUNTY AREA—A Case of Guangxi Zhuang Autonomous Region, China 被引量:1
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作者 Liao Chi-mei Li Lan +1 位作者 Yan Zhi-qiang Peng Ding-xin 《Chinese Geographical Science》 SCIE CSCD 2002年第1期61-67,共7页
Sustainable use of natural resources is different from sustainable development. As the most important natural resource, sustainable use of land resource is the essential guarantee of sustainable development. The natur... Sustainable use of natural resources is different from sustainable development. As the most important natural resource, sustainable use of land resource is the essential guarantee of sustainable development. The nature of sustainable use of land resource is to retain the quantity and productivity of land resource from generation to generation.The evaluation of sustainable use of land resource is an important method to ensure land use to get onto the sustainable track. Furthermore, building index system is the key of the evaluation. In view of tendency of the evaluation indexes chosen so widely, the evaluation indexes should include only three kinds in the researches on the evaluation of sustainable use of land resource. The first is the stock and structure index of land resource, viz. Areas quantity structure of land resources. In China, it is especially paid attention to the per person index of land quantity and rate between cultivated land and farmland. The second is the productive index of land, which includes the productivity, potentiality, stability and renewal situation of land. The third is the sustained index of land environment. On the evaluation research of area level, we should lay particular emphasis on statistic indexes. With a case of Guangxi Zhuang Autonomous Region in China, the evaluation index system of sustainable land use in county area has been built in this thesis. Using the weighted average method to calculate the means of sustainable land use in each county, according to the land using situation, all counties in the autonomous region have been divided into three types. (1) Sustainable Pattern contains 18 counties, which have higher land resource productivity, stronger sustained abilities of land environment .The economic benefits of land using in these counties are obviously higher. These counties have gotten highly intensive farming, and they are all in the good circumstance. (2) Basically Sustained Pattern contains 48 counties, which productivity of land resource is of middle level. In part of counties and cities, the stock of land resource inclines to lower level, but their land using potentialities are still greater. Through changing land using pattern, these counties can rapidly enter in a good circumstance. (3) Critically Sustained Pattern contains 14 counties, which are mostly in the karst mountain areas. They have less stock of land resource, lower productivity and more extensive cultivation. The productivity of land renewing has been hindered, so it urgently need to be renovated. At last, the writers have explored the basic ways of sustainable use of land resource in Guangxi, China — (1) Retain the stock of land resource and strictly manage farmland uses. (2) Strengthen the value accounting of land resource, and control the farmland occupation of non agricultural construction. (3) Depend on technology advanced, optimize the land using structure, and promote the productive level. (4) Carry out land management all round, and improve the ecological environment of land resource. (5) Enhance evaluation researche and land monitoring, and promote the sustainable utilization level of land resource. 展开更多
关键词 sustainable use of land resource land evaluation evaluation index county area GUANGXI
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Steam Reforming of Natural Gas: A Value Addition to Natural Gas Utilization in Nigeria 被引量:1
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作者 Minister Ezekiel Obonukut Sunday Boladale Alabi Perpetua George Bassey 《Journal of Chemistry and Chemical Engineering》 2016年第1期28-41,共14页
Petrochemicals play a vital role in the economy of any nation. The products of the industry are the building blocks in many industries as they deepen the forward and backward linkages of the petroleum sector with the ... Petrochemicals play a vital role in the economy of any nation. The products of the industry are the building blocks in many industries as they deepen the forward and backward linkages of the petroleum sector with the rest of the economy. The industry uses a variety of hydrocarbon feedstock such as different cuts of naphtha from refinery and natural gas. One of the problems facing the industry is lack of reliable feedstock supplies. Nigeria has the potential to be a major petrochemicals producer. With proven gas reserves currently estimated at 187 tcf, not much has been accomplished with respect to the effective exploitation and utilization of this resource as most of the nation's natural gas production has been flared, liquefied for export or re-injected to enhance greater crude oil recovery. It has become imperative to further find ways to exploit and utilize the nation's natural gas reserves and translate it to the improvement of the nation's economy. Steam reforming of natural gas is one of the avenues for conversion of natural gas to petrochemicals. This paper, however, reviews various ways of utilizing natural gas, examines the process details of steam reforming of natural gas as a route to optimized natural gas utilization and industrialization in Nigeria. Syngas (synthesis gas) is a versatile feedstock for most petrochemicals and chemical intermediates. Thus utilizing natural gas in this way would strengthen the petrochemical industry making it possible for the country to change from raw materials to value-added products supplier, boost the economy and solve the "hydra-headed" problem of unemployment in Nigeria with its multiplier employment effect. 展开更多
关键词 Natural gas PETROCHEMICALS steam reforming synthesis gas.
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