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Risk-opportunity analyses and production peak forecasting on world conventional oil and gas perspectives

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Petroleum Science 2010年第1期7卷 136-146页

作者： Zhang Jian Sun Zandong Zhang Yiwei Sun Youshun Nail Toksoz ~Lab for Integration of Geology and Geophysics China University of Petroleum Beijing 102249 China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing 102249 China Earth Resources Laboratory Massachusetts Institute of Technology 77 Mass. Ave Cambridge MA 02139 USA

To investigate the situation of conventional oil and gas, this paper examines the global oil and gas discoveries, proved reserves, production, consumption and price. All the influencing factors can be subjected to risk and opportunity analyses, so in the paper, we build upon a risk-opportunity analysis framework, which is a new train of thought. To forecast the peak time of oil and gas production, we used the methods of multi-Hubbert model forecasting and data forecasting. Our results showed that the world oil production will reach a peak between 2010 and 2015 and the gas production will reach a peak around 2030 Oil peak is coming and gas peak is on the way. The main purpose of forecasting oil and gas production peak is give people enough time for preparing mitigation and adaptation plans. This means taking decisive action well before the problem is obvious.

关键词： Production reserve risk opportunity forecasting

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Challenge and opportunity of ionic liquidsdAn interview with *** ***

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Green Energy & Environment 2020年第2期5卷 243-245页

作者： Jing Kong Hongyan He Institute of Process Engineering Chinese Academy of SciencesBeijing100190China Green Energy&Environment(GEE)Editorial Office China

Expert Profile:*** *** is an Australian Laureate Fellow at Monash University's School of Chemistry and leader of the Energy Program in the Australian Centre for Electromaterials *** is the Australian Academy of Scienc... 详细信息

关键词： interview Australian opportunity

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Inequality of opportunity in China's Labor Earnings: The Gender Dimension

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China & World Economy 2019年第1期27卷 28-50页

作者： Jane Golley Yixiao Zhou Meiyan Wang Australian Centre on China in the World Australian National University Australia School of Economics Finance and PropertyCurtin University Institute of Population and Labor Economics Chinese Academy of Social SciencesChina

This paper investigates the inequality of opportunity in China's labor earnings,defined as the component of inequality determined by personal circumstances that lie beyond the control of an individual,of which gender is one,as opposed to the component determined by personal *** the Survey of Women's Social Status in China (2010),we measure the share of inequality of opportunity in the total inequality of individual labor earnings for people aged 26-55 years,and separately for six birth cohorts and for female and male *** is revealed as the single most important circumstance determining nationwide individual labor earnings,with one's region of residence, father's occupation,father's education,birth cohort and holding rural or urban hukou also playing significant roles.A further investigation into the roles of circumstances and personal efforts (including education level,occupation,Communist Party membership, migration and marital status)confirms that circumstances *** alarmingly high role in shaping labor earnings distribution in China,and reveals notable gender differences that cannot be attributed to personal effort *** results provide the basis for recommending ways to improve gender equality of opportunity in the future.

关键词： China gende inequality of opportunity

Measurement and analysis of content diffusion characteristics in opportunity environments with Spark

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Frontiers of Information Technology & Electronic Engineering 2019年第10期20卷 1404-1414页

作者： Xiao-hong ZHANG Kai QIAN Jian-ji REN Zong-pu JIA Tian-peng JIANG Quan ZHANG College of Computer Science and Technology Henan Polytechnic UniversityJiaozuo 454000China Beijing Anqi Zhilian Technology Co. Ltd.Beijing 100000China Department of Computer Science Wayne State UniversityDetroit 48202USA

opportunity networks provide a chance to offload the tremendous cellular traffic generated by sharing popular content on mobile networks. Analyzing the content spread characteristics in real opportunity environments can discover important clues for traffic offloading decision making. However, relevant published work is very limited since it is not easy to collect data from real environments. In this study, we elaborate the analysis on the dataset collected from a real opportunity environment formed by the users of Xender, which is one of the leading mobile applications for content sharing. To discover content transmission characteristics, scale, speed, and type analyses are implemented on the dataset. The analysis results show that file transmission has obvious periodicity, that only a very small fraction of files spread widely, and that application files have much higher probability to be popular than other files. We also propose a solution to maximize file spread scales, which is very helpful for forecasting popular files. The experimental results verify the effectiveness and usefulness of our solution.

关键词： Content dissemination Device-to-device communication opportunity network Linear threshold model

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opportunity Costs of Emissions Caused by Land-Use Changes

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Open Journal of Forestry 2014年第1期4卷 85-90页

作者： S. Suyanto Andree Ekadinata Muhammad Sofiyuddin Arif Rahmanullah World Agroforestry Center (ICRAF Southeast Asia Program) Bogor Indonesia

Amid the euphoria of Reducing Emissions from Deforestation and Forest Degradation (REDD) and REDD+ discussions, the expectations of large financial gains raise the interest of all. A country, however, will only enjoy REDD benefits if the cost of REDD is lower than the benefit. The opportunity cost analysis is an effective tool for assessing the feasibility of REDD+ since the largest portion of costs associated with REDD+ and can help to identify fair compensation for those who change their land use. The opportunity cost analysis has been exercised in Tanjung Jabung Barat (Tanjabar) district-Indonesia to examine the economic-feasibility of carbon emission reduction under different type carbon price scenarios. This study reveals a sharp decline of land-use systems with high carbon-stock and low profitability is obvious. On mineral soil, low carbon-stock and high profitability (mostly oil palm) has increased rapidly, especially in the period 2000-2009. It has become the dominant land-use system. The low-to-medium carbon stock and medium profitability land-use category increased from 1990 to 2005 but declined from 2005 to 2009. The low carbon-stock and low profitability category was constant and the proportion of the area was below 15%. The ex-ante analysis in predicting the potential for future emissions reduction in Tanjabar through REDD+ approaches shows that the cumulative emission of Tanjabar in 2020 is estimated at 61.91 Mg CO2-eq/***, while the reduced emission by excluding all land use conversion below $5 threshold is estimated at 51.71 Mg CO2-eq/***. This means that there is a potential for 16% emission reduction using $5/ton CO2-eq incentive. Another important finding in this study is that if the price of carbon increases by double to $10, the amount of reduced emission does not change much. This can use as a basis for determining the right amount of incentive for trade-off between economic profitability and climate change mitigation effort in Tanjabar

关键词： opportunity Cost Land Use Change Carbon Emission REDDS

Measuring the effect of opportunity cost of time on participation in sports and exercise

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Open Journal of Preventive Medicine 2013年第5期3卷 380-392页

作者： Nana Kwame Anokye Subhash Pokhrel Julia Fox-Rushby Health Economics Research Group (HERG) Brunel University Uxbridge Middlesex UK

Background: There is limited research on the association between opportunity cost of time and sports and exercise due to lack of data on opportunity cost of time. Using a sample of 14142 adults from Health Survey for England (2006), we develop and test a composite index of opportunity cost of time (to address the current issues with data constraint on opportunity cost of time) in order to explore the relationship between opportunity cost of time and sports participation. Methods: Probit regression models are fitted adjusting for a range of covariates. opportunity cost of time is measured with two proxy measures: a) composite index (consisting of various indicators of wage earnings) constructed using principal component analysis;and b) education and employment, approach in the literature. We estimate the relative impact of the composite index compared with current proxy measures, on prediction of sports participation. Findings: Findings suggest that higher opportunity cost of time is associated with increased likelihood of sports participation, regardless of the time intensity of activity or the measure of opportunity cost of time used. The relative impacts of the two proxy measures are comparable. Sports and exercise was found to be positively correlated with income. Another important positive correlate of sports and exercise is participation in voluntary activity. The research and policy implications of our findings are discussed.

关键词： Physical Activity Sports and Exercise opportunity Cost of Time Index

Utilizing Occupancy Models and Platforms-of-opportunity to Assess Area Use of Mother-Calf Humpback Whales

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Open Journal of Marine Science 2018年第2期8卷 276-292页

作者： J. J. Currie S. H. Stack J. A. McCordic J. Roberts Pacific Whale Foundation Wailuku Maui USA

The Hawaiian Islands, and particularly the Maui 4-island region, are a critical breeding and calving habitat for humpback whales (Megaptera novaeangliae) belonging to the Hawaii distinct population segment. Our aims were to test the use of platforms-of-opportunity to determine trends in mother-calf pod use of the region and to present opportunistic platforms as an alternative method of long-term, cross-seasonal monitoring. Data were collected from whale watching vessels over a 4-year period and analyzed using occupancy models to determine the probability of habitat use of pods with calves and pods without calves within the study area. Detection probability was influenced by survey effort and month for all pod types with detection of adult only pods further influenced by year. Pods with a calf showed a preference for shallow (75 meters). Results presented here align with previous work, both in Hawaii and in other breeding grounds, which show a distinct segregation of mothers with a calf from other age-classes of humpback whales. The need for long-term continuous monitoring of cetacean populations is crucial to ensure species conservation. Data collected aboard platforms-of-opportunity, as presented here, provide important insight on humpback whale spatial and temporal distribution, which are essential for species protection and management.

关键词： Humpback Whale Occupancy Model Platform of opportunity Whale and Dolphin Tracker Area Use

Modeling Spatial opportunity Structures and Youths’ Transitions from School to Training

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Open Journal of Statistics 2017年第6期7卷 1013-1038页

作者： Alexandra Wicht Alexandra Nonnenmacher GESIS—Leibniz Institute for Social Sciences Mannheim Germany University of Siegen Siegen Germany

This paper examines the significance of spatial externalities for youths’ school-to-training transitions in Germany. For this purpose, it is necessary to address the methodological question of how an individual’s spatial context has to be operationalized with respect to both its extent and the problem of spatial autocorrelation. Our analyses show that the “zone of influence” comprises of the whole of Germany, not only close-by districts, and that these effects differ between structurally weak and strong regions. Consequently, assuming that only close proximity affects individual outcomes may disregard relevant contextual influences, and for spatial models that require an a priori definition of the weights for spatial units, it may be erroneous to make a decision based on this assumption. Concerning spatial autocorrelation, we found that neglecting local spatial autocorrelation at the context level causes considerable bias to the estimates, especially for districts that are close to the home district.

关键词： Spatial Effects Spatial Autocorrelation Event History Models Youths School-to-Work Transitions opportunity Structures

Analysis of Factors Influencing Farmers' Identification of Entrepreneurial opportunity

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Asian Agricultural Research 2013年第6期5卷 112-117,121页

作者： Jing GAO Fang YANG Center of Rural Economics and Management Southwest University School of Economics and Management Southwest University

Based on the survey data of entrepreneurship concerning farmers in China,this article uses the multivariate adjustment regression analysis method,to analyze the factors influencing farmers' identification of entrepreneurial opportunity and the mechanism. The results show that demographic characteristics are still an important factor influencing farmers' identification of entrepreneurial opportunity,but the extent of its influence is weaker than entrepreneurs' trait. The new trait theory is verified in farmers' entrepreneurship opportunity behavior; entrepreneurship environment is becoming an important factor influencing entrepreneurial opportunity identification,whose regulation effect on entrepreneurs' social network and previous experience is stronger than the regulation effect on entrepreneurs' psychological trait.

关键词： Farmers’ entrepreneurship opportunity behavior Inf