石油储量价值评价中运销成本级差模型的设计与检验

对石油资源价值评价中的4个成本因素之一——运销成本级差因素进行了讨论。文中分析了运销成本级差因素的组成因子之后．建立对之进行测算的数学模型，并就两个油田的实测数据给出了计算结果。     

Co-ordination of land exploitation,exploitable farmland reserves and national planning in China

Land exploitation, as an important strategy to mitigate farmland loss and stabilize grain production, has been adopted to compensate farmland loss due to rapid urbanization in China. Bounded by the limited capacity and obvious spatial variations of national farmland reserves, it is essential to arrange land exploitation activities timely and reasonably. In this study, we propose an indicator for the status of regional land exploitation, the Exploitation Degree, to facilitate an overview of land exploitation programs in China at both provincial and prefectural levels based on project data from 2006 to 2012. To further our understanding of the regional features of land exploitation activities, we employ the Lasso model to identify and quantitatively assess influencing factors on land exploitation. Our study shows that: (1) contemporary land exploitation practices in China are significantly inconsistent across exploitable farmland reserves. Some areas are greatly over-exploited and such irrational land exploitation has been persistent; (2) related national land plans designed to guide land exploitation efforts centered on resource-rich regions and critical areas do not function as intended. Therefore, we suggest that China⿿s land exploitation policy shall be improved by reconsidering the orientation of land exploitation policy, coordinating land exploitation activities with productivity improvements and eco-system protection, and enhancing the power and scope of the plans in controlling and guiding land resource management.     

Ecotourism as a conservation tool and its adoption by private protected areas in Brazil

Ecotourism in private reserves combines the establishment of protected areas with an incentive mechanism to conserve biodiversity. Brazil's private reserve system is well-established but little is known about its links to tourism. This study puts the global private protected area into context and quantifies the extent to which ecotourism has been adopted as a sustainable land-use practice on private reserves in Brazil. Our findings demonstrate that small reserves do contribute to conservation and are used for ecotourism. The belief that large reserves are necessary for ecotourism and conservation is challenged. Only 4% (n = 45) of the 1182 reserves are engaged in ecotourism, mainly those within the Atlantic Forest biome and these are generally small in size (<50 ha). Reserves provide modest to basic accommodation as well as education and economic opportunities that include adjacent communities. Hiking and bird watching are the most popular activities but many reserves are threatened by poaching and invasive species. The low adoption of ecotourism appears due to a combination of factors, including lack of landowner interest, constraints imposed by regulations, logistics and anthropogenic threats. Nonetheless, there is potential to expand ecotourism within private reserves as 143 further private reserves are located near those already engaged in ecotourism.     

The Relationship Between Sovereign Spreads and International Reserves: Does the Exchange Rate Regime Matter?

International reserves have been put forward as an important factor affecting sovereign spreads in the literature. This article empirically analyzes whether the relationship between international reserves and sovereign spreads depends on exchange rate policy in emerging markets. The analysis is carried out using exchange rate classifications based on both the officially declared regimes and the actual exchange rate behavior. The results show that international reserves reduce sovereign spreads for all levels of exchange rate flexibility using both classifications. Reserves have a similar effect on spreads for all exchange rate categories, except for hard pegs, under which the effect is larger.     

FX Intervention in the New Keynesian Model

We develop an open-economy New Keynesian Model with foreign exchange (FX) intervention in the presence of a financial accelerator and shocks to risk appetite in international capital markets. We obtain closed-form solutions for optimal monetary and FX intervention policies assuming the central bank cannot commit to future policies, and we compare the solution to that under policy commitment. We show how FX intervention can help reduce the volatility of the exchange rate, of inflation, and of the output gap, thus mitigating welfare losses associated with shocks in the international capital markets. We also show that, when the financial accelerator is strong, there is a risk of indeterminacy (self-fulfilling currency and inflation movements) although FX intervention can reduce this risk and thus reinforce the credibility of the inflation targeting regime. Model simulations match well the impact of a VIX shock obtained by local projections on a panel of inflation targeting emerging markets.     

综放工作面动态分次加架技术实践

针对一些不规则布置的综放工作面,介绍了当工作面长度变长时,采取不同的布置及加架方式的优缺点。这对于一些储量较少,地质条件复杂的矿井具有很好的借鉴意义。     

Central banks and macroeconomic policy choices: Relaxing the trilemma

Macroeconomic policy choices in open economies are constrained by the trilemma according to which the objectives of exchange rate stability, monetary independence and capital mobility cannot be attained jointly. This paper shows that foreign exchange interventions provide an effective instrument to relax the trilemma. An active reserve policy allows central banks to pursue independent monetary and exchange rate policies when the capital account is liberalised.We use the framework of the portfolio balance model to show that exchange market interventions may substitute for capital controls. Both allow a country to achieve the other two objectives of the trilemma. Our empirical analysis of a large country panel data set covering the period 1970–2010 confirms this theoretical insight: the weighted sum of the three trilemma objectives increases in the degree of foreign exchange market intervention. The capacity to relax the trilemma constraint has increased over time and has been most effective in emerging markets.     

The shadow costs of repos and bank liability structure

Making use of a structural model that allows for optimal liquidity management, we study the role that repos play in a bank׳s financing structure. In our model the bank׳s assets consist of illiquid loans and liquid reserves and are financed by a combination of repos, long-term debt, deposits and equity. Repos are a cheap source of funding, but they are subject to an exogenous rollover risk. We show that the use of repos inflicts two types of indirect (“shadow”) costs on the bank׳s shareholders: first, it induces the bank to maintain higher liquid reserves in order to alleviate the additional default risk; second, it adds to the cost of long-term debt financing. These shadow costs limit the bank׳s appetite for cheap but unstable repo funding. This effect is, however, weakened under poor returns on risky assets, access to deposit funding and the depositor preference rule. We also analyze the impact of a liquidity coverage ratio, payout restrictions and a leverage ratio on the bank׳s financing choices and show that all these tools are able to curb the bank׳s reliance on repos.     

对当前我国外汇储备基金实现投资增值的思考

外汇储备必须在满足流动性和安全性前提下,拓展投资渠道,控制投资风险,提高投资收益.近几年来,我国外汇储备持续高企,而外汇储备基金投资却只有3%的营运收益率.本文分析了我国外汇储备基金投资增值的现状,从区分管理功能和投资功能,组建高效基金运营模式;设定投资基准和投资限额,控制和规避投资风险;优化外汇储备的货币结构和资产结构,拓宽投资渠道;加快培养吸纳国际金融市场操作人才,完善有关法规等几个方面提出了改进外汇储备基金投资增值的对策.     

库存管理与国家石油储备

本文试用库存管理、"牛鞭子效应"、安全库存和库存成本等库存管理的基本理论,结合我国石油开采量与消费现状分析建设国家石油储备的重要性、迫切性和石油储备的相关成本。