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41.
本文阐述了在Arduino UNO上对MiFare One卡射频识别卡进行读写的软件实现,并重点描述了阅读器与卡片之间的通信过程。  相似文献   
42.
基于红外图像的林火识别方法及实现   总被引:1,自引:0,他引:1  
森林火灾是一种突发性强、破坏性大且处置救助较为困难的自然灾害,会对森林、森林生态系统和人类带来一定危害和损失。早期的林火判别多基于温度、烟雾以及24小时图像监测实现,主观性强,标准单一,且误报率高。如何快速发现林火目标并及时报警扑灭,已经成为国内外学者研究的热点之一。文章基于红外热像仪,对大量森林背景及模拟林火状态进行了图像和温度数据的采集,首次提出了基于温度标准差方法进行热源识别的概念,得出了不同地点、不同时间段森林背景的温度标准差分布,以及明火温度在各阶段的波动范围,为林火的预防和监测提供了重要依据。同时,通过对干扰源进入前后的红外图像进行预处理和分析,对比目标热源的像素面积变化率及其圆形度,即可准确实现部分干扰热源的排除。实验结果证明,将此基于红外图像的热源初判原则与干扰源排除的规律应用于林火监测,方法简单有效,准确率高,对降低森林火灾的发生率,提高社会经济效益有着重要的作用。  相似文献   
43.
Objective: Philadelphia chromosome negative [Ph(?)] relapsed or refractory (R/R) B-precursor acute lymphoblastic leukemia (ALL) is an extremely rare condition requiring intensive treatment. This retrospective chart review aimed to quantify hospitalizations and reimbursement in this patient population in France.

Methods: Patients aged ≥18 years and with at least one hospitalization for Ph(?) R/R B-precursor ALL were included in the study. They were relapsed with first remission lasting <12 months, relapsed after first salvage therapy, relapsed any time after hematopoietic stem cell transplant (HSCT), or were refractory to initial or salvage therapy. Data were collected from the index date (first diagnosis of R/R ALL) until death or loss to follow-up. The chemotherapy period was defined as the first chemotherapy date after the index date to the earliest of death, loss to follow-up, last chemotherapy dose plus 30 days, or initiation of HSCT. The primary outcome was the percentage of time hospitalized during the chemotherapy period.

Results: Thirty-three patients were included, with a mean age of 49 years. The mean proportion of time spent in the hospital during the chemotherapy period was 46% (95% CI =34–57%). Patients had a mean of 2.2 (SD =1.5) inpatient hospitalizations and the mean length of stay per hospitalization was 16.8 (SD =14.8) days. During the chemotherapy period, the mean amount reimbursed per hospitalization was €31 067 (SD = €4850) and the total hospitalization reimbursement per patient was €68 344. From the index date to death, excluding HSCT, the total reimbursement per patient was €108 873.

Limitations: The sample size was small, although this was expected given the rarity of the patient population.

Conclusions: Adults with Ph(?) R/R B-precursor ALL had repeated and prolonged hospitalizations during salvage chemotherapy. Approximately half the follow-up period was spent in the hospital, and this time was associated with high economic burden in France.  相似文献   
44.
This article explores how the adoption of company sponsored smart phones inflicts upon the lives of professionals. Drawing upon qualitative interviews at a law firm in Brazil, the experiences of new smart phone users are reported upon in detail. Increased accessibility, accuracy and speed in exchanges gave the users a sense of autonomy and flexibility. However, the technology also helped to intensify the organisation's hold on employees outside of regular working hours, reaching into new settings, time slots and social contexts. Employees expressed concerns regarding demands from superiors that negatively affected their private spheres, yet many of them paradoxically requested more efficient smart phone connectivity. The article focuses on the justifications, the different narrative strategies, employed by professionals for their conscious engagement in escalating work connectivity. It is suggested that these justifications display users' attempt to ‘dis‐identify’ with the role and practice they perform.  相似文献   
45.
刘元铚 《价值工程》2014,(20):183-184
针对近几年施工企业安全形势严峻,安全管理急需转型的形势完成本文。本文通过对企业安全管理的内部能力与外部因素运用SWOT分析,阐述了施工企业安全管理战略从过去突击式的安全大检查到以预防为主的危险源辨识管控的转变。  相似文献   
46.
Market characteristics, including intrinsic demand and customer sensitivity on price and product performance level, are distinct at different markets. Comparisons of various product development strategies in one market or two geographically separated markets are conducted for three classes of products: development intensive products (DIPs) with constant unit cost, marginal cost-intensive products (MIPs) with constant fixed cost, and marginal and development intensive products (MDIPs) with non-constant unit cost and fixed cost. Results show that larger demand size, less customer sensitivity on price and/or more sensitivity on performance level lead to more profit, a higher sale price and a not-lower product performance. The customer reservation or the saturation performance level should be generally adopted though the optimal performance level does exist occasionally. Unit cost and/or fixed cost must increase in performance at an increasing rate for the existence of one optimal performance level. Due to the impact of demand size, one high-end (low-end) MDIP or DIP could be introduced into one low-end (high-end) market at a different price if the demand size is significantly large in the low-end market. For DIPs, offering one niche high-end product is not worse than offering the low-end product into two markets. For MIPs with negligible fixed cost, the product line strategy is not worse than the standard product development strategy. Additionally, the product cost reduction approach adopted in one product line has significant effects on the best product development strategy and sequence.  相似文献   
47.
After more than 50 years of self‐regulation of the US auditing profession, the Sarbanes‐Oxley Act of 2002 (SOX) created the Public Company Accounting Oversight Board (PCAOB) as a quasi‐governmental entity with statutory authority to inspect accounting firms that audit public clients. The frequency of this inspection is annual or triennial, based upon the number of public clients the firm audits. We examine the effects of these two levels of inspection frequency on financial reporting quality and audit fees for clients of small and midsize public accounting firms. Our findings provide evidence of significantly higher audit quality and audit fees for clients of annually inspected firms relative to clients of triennially inspected firms. These findings are robust to auditor‐client alignment analyses, propensity score matching, time‐series analyses, examination of firms that have changed from triennial to annual inspection, and particular examination of firms with inspection deficiencies. Overall, our study suggests that the two‐tier frequency system of PCAOB inspection may have also resulted in two‐tier audit quality and audit fee systems for small and midsize public accounting firms, with more frequent inspection leading to more rigorous and informed auditor decisions. We discuss the implications of our results for the Board and the profession at large.  相似文献   
48.
Today’s companies still rely heavily on expert knowledge rather than quantitative data with a systematic approach to effectively identify and choose Research and Development (R&D) partners. It is advantageous to identify and select potential R&D partners using a Problem & Solution (P&S) pattern. This paper presents a novel process for identifying R&D partners on the basis of solution similarities that assist technology managers in understanding the relationships between research targets. First, we choose a thematic dataset that contains problems and quantitative data with relative topic terms. Then, we extract Subject-Action-Object semantic structures in a P&S pattern from the dataset, and identify various solutions to a technical problem, with each as a subject. In addition, we provide correlation mapping to visualise the text characters and identify R&D partners. Finally, we validate the proposed method through a case study of the dye-sensitized solar cells sector.  相似文献   
49.
This study examines the mediating role of group efficacy on the relationship between group affect and group identification by integrating the collective cognition process. Using a sample of forty-seven work groups in Study 1, the results show that group efficacy fully mediates the relationship between positive and negative group affect and group identification. Study 2 applies a two-wave panel design to verify the impact of group efficacy on group identification. The results of Study 2 indicate that group efficacy relates positively to the development of group identification. The implications for theory and practice are discussed.  相似文献   
50.
The purpose of this research was to examine the antecedents and consequences of brand prestige in the luxury cruise industry in order to provide luxury cruise managers with practical strategies for maximizing and utilizing brand prestige. Based on the existing theoretical background, it was hypothesized that eight types of cruise experience factors influence the formation of brand prestige: food quality, service quality, staff/crew attractiveness, entertainment, ship facilities, ports of call, programs/places for children, and cabin quality. In addition, it was proposed that brand prestige can result in three managerial outcomes: well-being perception, customer brand identification, and brand loyalty. A conceptual model was developed and tested using the empirical data collected from 330 U.S. luxury cruise passengers. The results showed that all of the proposed hypotheses were statistically supported. The key theoretical/managerial implications that were derived from the analysis are presented and discussed in the last part of the article.  相似文献   
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