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1.
[目的]以高分1号(GF-1)融合2m卫星遥感影像为基础数据源,结合土地利用现状数据、高分多源遥感影像和地面样方等数据,对冬小麦分类提取中存在的面积误差问题进行研究和分析。[方法]文章以河南省永城市为研究区,在冬小麦提取结果聚类处理基础上,基于线性地物缓冲区数据,采用GIS空间运算实现线性地物面积扣除,接着分析了样方数据和土地利用现状数据再扣除零星地物面积比例上的差异,并采用样方零星地物平均扣除系数对全市各乡镇耕地与非耕地中冬小麦提取面积进行了相关统计和误差分析。[结果]永城市冬小麦最终解译面积11. 29万hm~2,其中线性地物和零星地物扣除面积分别为6 613. 08hm~2和3 875. 22hm~2,占研究区冬小麦解译面积的5. 86%和3. 32%,与统计上报数据相比,其处理前后误差由14. 12%降低至4. 41%,有效地提高冬小麦提取面积精度。[结论]误差来源分析与修正对冬小麦解译面积核算精度具有重要影响,该研究为县级区域尺度下冬小麦面积提取核算提供了思路和借鉴。  相似文献   
2.
We investigate the impact of direct payments on agricultural commercialisation in Kosovo. Kosovo is one of the poorest countries in Europe but, with European assistance, provides substantial funds to support agriculture, made up of many small and often semi‐subsistence farms. Thus, the effect of this support is a central policy issue. Identifying the effect of direct payments on market participation faces endogeneity issues arising from the possible simultaneous determination of participation in support programmes and market participation. In order to achieve proper identification of the endogenous direct payments, we use a strategy of targeted identification search that employs several different methodological approaches. We find that direct payments for fruit and vegetables, and those for cereals and oilseeds have a positive effect on market participation. However, we cannot identify any definite effect of livestock payments.  相似文献   
3.
Aims: The EINSTEIN-Extension trial (EINSTEIN-EXT) found that continued treatment with rivaroxaban for an additional 6 or 12 months (vs placebo) after 6–12 months of initial anticoagulation significantly reduced the risk of recurrent venous thromboembolism (VTE) with a small non-significant increased risk of major bleeding (none fatal or in critical site). This study aimed to compare total healthcare cost between rivaroxaban and placebo, based on the EINSTEIN-EXT event rates.

Methods: Total healthcare cost was calculated as the sum of treatment and clinical event costs from a US managed care perspective. Treatment duration and event rates were obtained from the EINSTEIN-EXT study. Adjustment on treatment duration was made by assuming a 10% non-adherence rate. Drug costs were based on wholesale acquisition costs. Cost estimates for clinical events (i.e. recurrent deep vein thrombosis [DVT], recurrent pulmonary embolism, major bleeding, clinically relevant non-major bleeding) were determined from the literature. Results were examined over a ±20% range of each cost component and over 95% confidence intervals (CIs) of event rate differences in deterministic (one-way) and probabilistic sensitivity analyses (PSA).

Results: Total healthcare cost was $1,454 lower for rivaroxaban-treated (vs placebo-treated) patients in the base-case, with a lower clinical event cost fully offsetting drug cost. The cost savings of recurrent DVT alone (–$3,102) was greater than drug cost ($2,723). Total healthcare cost remained lower for rivaroxaban in the majority (73%) of PSA (cost difference [95% CI]?=?–$1,454 [–$2,396, $1,231]).

Limitations: This study was conducted over the 1-year observation period of the EINSTEIN-EXT trial, which limited “real-world” applicability and examination of long-term economic impact. Assumptions on drug and clinical event costs were US-based and, thus, not applicable to other healthcare systems.

Conclusions: Total healthcare costs were estimated to be lower for patients continuing rivaroxaban therapy compared to those receiving placebo in VTE patients who had completed 6–12 months of VTE treatment.  相似文献   
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5.
世界主要工业发达国家以及亚洲“四小龙”在工业化过程中,尤其是在工业化初期和中期,作为劳动密集型的纺织工业具有重要的推动和关联作用。从目前和今后一段时期我国经济发展和工业化趋势来看,纺织工业在21世纪前50年间,在出口创汇、增加就业、扩大消费等方面仍将为我国国民经济发展起到重要的支撑作用,这种作用是其他产业一时难以取代的。这与中国纺织工业在原料供给、加工能力、产业体系、劳动力成本及素质等方面仍然具有明显的比较优势,以及占有世界市场最多的份额作为竞争的基础有着直接关系。由此,依靠科技、深化改革把我们的纺织大国建成纺织强国越来越具有重要的战略意义。  相似文献   
6.
本文阐述了跨文化管理的基本原则,重点探讨了企业实施跨文化管理的主要方法。  相似文献   
7.
探讨了物流在经济生活中的作用和现阶段我国物流产业方面存在的问题。提出了发展我国物流产业的基本途径。指出了我国的物流企业应该适时调整经营战略。顺应世界经济的发展趋势。不断提高自身的生存和发展能力。以应对未来更为激烈的竞争局面。  相似文献   
8.
货币政策的目标是多元化的,如价格稳定、经济增长等。通过货币政策的调整可以发挥其调节经济的效能。在货币政策协调过程中,运用好与其它社会经济政策的关系,对于提高宏观调控的科学性大有裨益。  相似文献   
9.
Australia is unusual among the world's antitrust jurisdictions in not making the pre‐notification of mergers compulsory. However, if the parties are concerned that the Australian Competition and Consumer Commission (ACCC) is likely to object to the merger, there are strong incentives for them to notify the ACCC as the regulator has developed a strong reputation for imposing heavy costs on parties that fail to notify such mergers. The result is a system of quasi‐compulsory notification that creates the strongest incentives for parties to notify the ACCC of those proposals to which it is most likely to object. This study analyses data extracted from the ACCC's merger database and the empirical results are consistent with this characterisation. Mergers reported voluntarily by the parties are found to experience longer delays to completion, and are more likely to be challenged by the ACCC, when compared with a sample of all other mergers assessed by the regulator. The results suggest that non‐compulsory notification allows the parties themselves to pre‐sort the proposed merger vis‐à‐vis its interest to the ACCC.  相似文献   
10.
On the morrow of President Truman's election the newspapers announced that the first person the President had received was the President of the powerful American syndical organisation known throughout the world under the name of C.I.Q. (Congress of Industrial Organizations). We know that this organisation as well as the other central organisation, the American Federation of Labour, had unequivocally taken up its stand in favour of Truman's candidacy. As the legislative elections had at the same time given the majority to the Democratic Party it was immediately declared on all hands that trade-unionism was going to exert considerable influence on American policy. These facts conferred a great importance on the memorandum addressed by Mr. Philipp Murray, in November 1947, to President Truman; a memorandum which was officially communicated by the C.I.O. to the International Trades Unions Conference for the recovery and reconstruction of Europe held in London on the 9th and 10th of March, 1948. We are especially pleased to put this document, which constitutes a declaration of principles of tie utmost interest, before the readers of the Annals.  相似文献   
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