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61.
金倩仪 《现代食品》2021,27(1):167-170
通过参加2020年食品安全抽检监测工作承检机构微生物检验实验室间比对,分别对菌落总数、大肠菌群和沙门氏菌进行盲样考核,对实验室人员和技术的能力进行评估并提高实验室的检验能力.结果表明,4个样品的检验结果均取得满意的反馈.  相似文献   
62.
杨硕  郜金金  孙迪  张文  张仁松 《现代食品》2021,27(2):102-104
采集和保存样品是食品微生物检验工作的第一步,对后续的微生物检验工作的顺利开展至关重要.食品微生物检验样品的质量和状况对检验结果起着决定性作用.因此,现就食品微生物检验样品的采集、保存、检验过程进行探究,其目的是保障食品微生物检测结果能够真实反映其食品安全现状.  相似文献   
63.
This paper assesses the impact of the ‘decoupling’ reform of the Common Agricultural Policy on the labour allocation decisions of Irish farmers. The agricultural household decision‐making model provides the conceptual and theoretical framework to examine the interaction between government subsidies and farmers’ time allocation decisions. The relationship postulated is that ‘decoupling’ of agricultural support from production would probably result in a decline in the return to farm labour but it would also lead to an increase in household wealth. The effect of these factors on how farmers allocate their time is tested empirically using labour participation and labour supply models. The models developed are sufficiently general for application elsewhere. The main findings for the Irish situation are that the decoupling of direct payments is likely to increase the probability of farmers participating in the off‐farm employment market and that the amount of time allocated to off‐farm work will increase.  相似文献   
64.
In a recent paper, Rouse and Daellenbach (1999) provide a five‐step methodological approach which they feel will cure alleged inadequacies in empirical resource‐based research. We suggest, however, that their methodology can provide only a useful aid for expanding our understanding of potential sustainable competitive advantages but will not allow researchers to effectively verify those hypothesized advantages. Specifically, we argue that Rouse and Daellenbach's methodology is plagued by three major shortcomings: (1) it confuses the important distinction between knowing‐how and knowing‐what; (2) it fails to recognize the importance of observable variables in verifying the sources of sustainable competitive advantage; and (3) it calls for sampling on the dependent variable. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
65.
Sample design and sample allocation methods are developed for random digit dialling in household telephone surveys. The proposed method is based on a two-way stratification of telephone numbers. A weighted probability proportional to size sample allocation technique is used, with auxiliary variables about the telephone coverage rates, within local telephone exchanges of each substrata. This makes the sampling design nearly “self-weighting” in residential numbers when the prior information is well assigned. A computer program generates random numbers for the local areas within the existing phone capacities. A simulation study has shown greater sample allocation gain by the weighted probabilities proportional to size measures over other sample allocation methods. The amount of dialling required to obtain the sample is less than for proportional allocation. A decrease is also observed on the gain in sample allocation for some methods through the increasing sample sizes.  相似文献   
66.
This paper investigates the impact of R&D disclosure and finance variables on the level of R&D expenditures. The question addressed is: what is the impact of changes in disclosure requirements on the relationship between R&D expenditure and the financing of firms? The question is motivated by the possible signalling role that elective disclosure may have had prior to changes in accounting practices to ensure R&D disclosure.  相似文献   
67.
68.
Survey data from PhD-granting economics departments are used to assess the teaching preparation of graduate students in economics. The results show that relatively few departments require graduate student instructors to take a credit course in teaching before teaching their own course or leading a recitation section. Although more graduate student instructors are required to take a noncredit course in teaching before serving as an instructor or recitation leader, the value of such noncredit courses may be limited. The assessment of teaching preparation by department chairs shows mixed responses, with about three-fifths rating it as very good or good and about two-fifths considering it to be only adequate or poor. Recommendations are offered for improving the teaching preparation of graduate student instructors in economics.  相似文献   
69.
This paper analyzes the persistence of inflation in the euro area and, in particular, whether the persistence properties have changed since the start of European Monetary Union(EMU). For that purpose, we compare pre‐ and post‐EMU inflation persistence, use rolling‐window estimates of persistence, and apply tests specifically designed to detect break dates near the end of the sample period. In contrast to previous research, we find that inflation persistence has fallen significantly since the start of EMU. Persistence of consumer price inflation, which is central to the European Central Bank's policy mandate, has fallen more than the persistence of deflator inflation. The drop in inflation persistence is consistent with the results from a simulated small New Keynesian model with a shift toward a more aggressive monetary policy stance.  相似文献   
70.
文章提出了一种针对小样本训练集的人脸图像超分辨率重构算法。该算法在马尔可夫网络模型的基础上,将视觉相容性检查准则引入到候选分块的匹配准则中,提高了匹配精度和块间兼容性。将权值机制融合进图像的重构过程,强化了训练集的有用性。实验表明,在小样本训练集下,算法能有效地抑制块效应和局部失真现象,明显改善超分辨率图像的质量。  相似文献   
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