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41.
《工程(英文)》2020,6(12):1395-1402
In this report, we show that hyperspectral high-resolution photoluminescence mapping is a powerful tool for the selection and optimization of the laser ablation processes used for the patterning interconnections of subcells on Cu(Inx,Ga1−x)Se2 (CIGS) modules. In this way, we show that in-depth monitoring of material degradation in the vicinity of the ablation region and the identification of the underlying mechanisms can be accomplished. Specifically, by analyzing the standard P1 patterning line ablated before the CIGS deposition, we reveal an anomalous emission-quenching effect that follows the edge of the molybdenum groove underneath. We further rationalize the origins of this effect by comparing the topography of the P1 edge through a scanning electron microscope (SEM) cross-section, where a reduction of the photoemission cannot be explained by a thickness variation. We also investigate the laser-induced damage on P1 patterning lines performed after the deposition of CIGS. We then document, for the first time, the existence of a short-range damaged area, which is independent of the application of an optical aperture on the laser path. Our findings pave the way for a better understanding of P1-induced power losses and introduce new insights into the improvement of current strategies for industry-relevant module interconnection schemes. 相似文献
42.
43.
Meimei Xia Jian Chen Xiao‐Jun Zeng 《International Transactions in Operational Research》2020,27(2):1080-1100
Existing approaches to data envelopment analysis focus mainly on the derivation of the efficiency of the individual decision‐making unit (DMU) or on the calculation of the weights of multiple inputs or outputs, but pay little attention to the team interest of all the DMUs. Motivated by the idea of team reasoning, in which the benefit of the team is of higher importance than that of each individual, this paper considers all the DMUs as a team and introduces the team indexes including the overall efficiencies, variance, boundaries of all the DMUs, and relationships between DMUs. Several models are first developed to estimate values of the team indexes based on which decision makers can provide their preferences regarding them. Then, models are established to obtain the interval efficiencies of individual DMUs under the condition that the team indexes are satisfied. Several examples are given to illustrate the proposed approaches and verify their applicability. 相似文献
44.
针对传统低压回路电阻测试仪只能在被测设备停电时使用的一大限制,本文提出并设计了一种新型低压回路电阻测试仪。该仪器可在低压设备运行状态下对其回路电阻进行测量,在保证测量精度的前提下减少了设备停电率,大大提高了工作效率。 相似文献
45.
城市生态文明建设依托于生态效率的改善,基于2005—2016年长江经济带107座城市面板数据,采用超效率SBM(slacks-based measure)模型测算生态效率,并结合探索性空间分析与空间马尔科夫链等探讨生态效率时空演化格局的内在规律, 实证分析生态效率驱动因素的影响效果。研究表明:2005—2016年经济带生态效率总体呈平稳态势,上、中、下游呈现“阶梯型”分布,下游依次优于中游和上游地区,部分地区生态效率呈“两级型”分化趋势;城市间生态效率发展存在空间联动效应,与生态效率高的城市为邻,其正向溢出作用促进城市状态向高水平跃迁,而与生态效率低的城市为邻,其负向作用拉动城市状态向低水平发展;人口规模与产业升级对经济带不同流域具有异质性作用,其提升下游生态效率而抑制中游和上游生态效率,产业升级与生态效率存在“U”型关联,意味着产业升级在短期内并不能使生态效率状态改善,而经济发展有利于促进生态效率向高水平状态演变。 相似文献
46.
J. Deming D. Gleeson T. ODwyer J. Kinsella B. OBrien 《Journal of dairy science》2018,101(10):9527-9543
With the cessation of milk quotas in the European Union, dairy herd sizes increased in some countries, including Ireland, with an associated increase in labor requirement. Second to feed costs, labor has been identified as one of the highest costs on pasture-based dairy farms. Compared with other European Union countries, Ireland has historically had low milk production per labor unit; thus, optimization of labor efficiency on farm should be addressed before or concurrently with herd expansion. The objective of this study was to quantify current levels of labor input and labor efficiency on commercial pasture-based dairy farms and to identify the facilities and management practices associated with increased labor efficiency. Thirty-eight dairy farms of varying herd sizes, previously identified as labor-efficient farms, were enrolled on the study and data were collected over 3 consecutive days each month over a 12-mo period, starting in May 2015 and finishing in August of 2016. This was achieved through the use of a smartphone application. For analysis purposes, farms were categorized into 1 of 3 herd size categories (HSC): farms with <150 cows (HSC 1), 150–249 cows (HSC 2), or ≥250 cows (HSC 3). Overall farm labor input increased with HSC with 3,015, 4,499, and 6,023 h worked on HSC 1, 2, and 3, respectively. A higher proportion of work was carried out by hired staff as herd size increased. Labor efficiency was measured as total hours input to the dairy enterprise divided by herd size. Labor efficiency improved as herd size increased above 250 cows with 17.3 h/cow per yr observed for HSC 3; labor efficiency was similar for HSC 1 and 2, at 23.8 and 23.3 h/cow per yr, respectively. A large range of efficiency was observed within HSC. The labor requirements had a distinct seasonal pattern across the 3 HSC with the highest input observed in springtime (February to April) primarily due to calving and calf-care duties, milking, and winter feeding. The lowest input was observed in wintertime (November to January) when cows were dry. Particular facilities and management practices were associated with efficiency within certain tasks, the most notable in regard to milking and winter feeding practices. Additionally, the most efficient farms used contractors to perform a higher proportion of machinery work on farm than the least efficient farms. 相似文献
47.
The assessment of efficiency is always of particular importance according to different indicators from different perspectives. There are various techniques for evaluating petrochemical companies, among which the data envelopment analysis technique is one of the best techniques that can be used to calculate the relative efficiency of a set of decision-making units with network structures. In the present paper, seven petrochemical companies listed in the Iranian stock exchange were analysed. These companies were evaluated in terms of financial performance and sustainable development, and their relative efficiency was calculated during 2015–2016. According to the obtained results, only Marun Petrochemical Co. was found to be efficient in all areas and years. The results also showed that four companies were efficient in financial terms over the period under study. In the general conclusion regarding the companies' performance, Marun was ranked first, Jam was ranked second, and Zagros was ranked third. 相似文献
48.
数字游戏常被认为是继文学、绘画、音乐等传统艺术之后的“第九艺术”。然而,长期以来,由于游戏的评价标准被商业体系左右,造成了游戏创作在思想层面的偏颇,所以设计师有必要建立一套针对数字游戏的艺术评价标准,以促进游戏的艺术创作和理论研究。从艺术思潮、艺术哲学和设计创新的角度出发,通过美学历史文献查阅、游戏艺术作品案例分析、艺术理论辨析等方法,就游戏的核心艺术因素展开论述。游戏的艺术标准应包括情感表现、艺术反思和创新性三个主要方面。其中,艺术情感是所有艺术的共性和核心;艺术反思是艺术理念的升华和艺术创作的动机;创新性则是艺术更替发展的内在动力。该标准独立于商业体系,将有助于促进和引导数字游戏在艺术层面的发展。 相似文献
49.
摘要:对腿部运动意图识别算法的实时性能进行综合可靠的评价是实现下肢假肢灵活稳定控制的前提。提出一种逐层分级的基于下肢运动意图识别算法的实时测评方法,对算法的可靠性、稳定性以及运动意图识别速度进行综合评价。利用开发的运动意图识别算法评测系统,对基于肌电信号源和机械信号源的两种运动意图识别算法进行了实时性能测试,发现肌电信号源的算法识别时间大于机械信号源算法,但是其算法稳定性优于机械信号源算法。进一步地,还利用该评测系统有效地区分出正常识别策略与异常识别策略,发现正常策略的动作识别稳定系数比异常策略高25%左右。因此,所提的基于下肢运动意图识别算法的实时测评方法,能够对不同信号源算法以及不同识别策略的实时性能进行有效评价,为智能下肢假肢控制系统开发提供可供参考的测试平台。 .txt 相似文献