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271.
目的 柔性卫生用品由于其材料表面不平整、产品容易发生变形等特性,给机器视觉中图像关键区域的定位和分割带来了很大问题,从而影响检测结果。为了解决复杂底纹柔性卫生用品表面脏点的检测问题,提出一种新型检测算法,以实现对复杂底纹柔性卫生用品快速又精准的检测。方法 在该检测算法中首先对采集的模板图像和样本图像进行预处理,在模板图像中创建一个合适特征模板,根据特征模板进行样本图像的匹配和定位;然后把经过精准定位后的样本图像进行关键区域分割;最后运用差影法把样本关键区域中的缺陷找出。该算法采用德国MVtec公司的halcon算子加以编程实现。结果 实验结果显示,该算法能够识别棉芯表面大于0.04 mm2的脏点,检测1幅图片的平均时间平均在100 ms,检测准确率为100%。结论 文中方法与传统方法相比,鲁棒性强,速度快,能够满足工业高速生产的需求。 相似文献
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273.
AbstractExposure assessment models are deterministic models derived from physical–chemical laws. In real workplace settings, chemical concentration measurements can be noisy and indirectly measured. In addition, inference on important parameters such as generation and ventilation rates are usually of interest since they are difficult to obtain. In this article, we outline a flexible Bayesian framework for parameter inference and exposure prediction. In particular, we devise Bayesian state space models by discretizing the differential equation models and incorporating information from observed measurements and expert prior knowledge. At each time point, a new measurement is available that contains some noise, so using the physical model and the available measurements, we try to obtain a more accurate state estimate, which can be called filtering. We consider Monte Carlo sampling methods for parameter estimation and inference under nonlinear and non-Gaussian assumptions. The performance of the different methods is studied on computer-simulated and controlled laboratory-generated data. We consider some commonly used exposure models representing different physical hypotheses. Supplementary materials for this article are available online. 相似文献
274.
《Contact lens & anterior eye》2019,42(4):411-414
PurposeTo investigate if the application of Blephagel, an eyelid cleansing gel, causes subjective and/or objective cooling effects by measuring ocular symptomology and temperature.MethodsTwenty-five healthy subjects underwent baseline non-invasive temperature measurements on the closed upper eyelid (centrally, nasally, and temporally) and ocular surface temperature (OST) on both eyes using an infrared camera. A standard application of Blephagel was then applied to the closed upper eyelid and eyelashes with a sterile cotton-wool to one eye selected at random. Temperature measures were then repeated on both eyes after 30–60, 120–150, and 180–210 s. At each interval, subjects rated the comfort and any cooling sensation of each eye on a 0–10 scale.ResultsAfter application of the gel, there was a significant difference in temperature at all locations on the eyelid between the test and control eyes over time (F = 9.322, p < 0.001). Post hoc analysis revealed this was significant from 30 to 60 s interval (36.3 ± 1.1 °C versus 37.2 ± 0.7 °C; p < 0.001) and the 120–150 s interval (36.8 ± 0.8 °C versus 37.2 ± 0.6 °C; p < 0.001). There was no significant variation between the OST locations over time (F = 3.350, p = 0.07). With respect to symptoms, there was a significant increase in cooling sensation in the test eye compared to the control eye over time (F = 10.438, p < 0.001), that remained throughout the experiment.ConclusionsBlephagel produces a reduction in temperature of the eyelids that is accompanied with a subjective cooling sensation. 相似文献
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《Food Control》2017
The aim of this study was to check the compliance of street food vendors hygienic practices with requirements of the Codex code of practice - general principles on food hygiene and of the Regulation (EC) No. 852/2004. The materials were 110 street food vendors located in Athens, Greece. Specially designed questionnaire allowed fast data collection. The lowest ratings were found in the hygiene of food preparation and serving, that was related to basic infrastructure, especially the protection of light bulbs from glass spreading in case of breaking, and protection of hair from falling into food by wearing sufficient hair covers or caps. Much higher ratings were found in separation of fresh food from ready-to-eat one and in the section of personal hygiene - lack of visible cuts or skin disease symptoms on hands. One of the most interesting findings is that street vendors selling meat or fish meals obtained higher ratings than vegetable or fruit ones. A greater effort should be made to increase hygiene level especially in the case of small mobile food vendors. Because of variation in hygiene level there is a need for more inspections covering greater number of street food vendors. Due to high popularity of street food and its importance for tourism, more effort should be made to improve the degree of compliance with the hygiene requirements. The fast observation questionaire used in this study allowed rapid assessment of implementation of hygiene principles. Further research is needed to explain why, despite food safety authorities licencing and inspection, implementation of hygiene principles by street food vendors is often incomplete and what factors affect the correct operation. 相似文献
277.
《Food Control》2015
Poor hand hygiene is a leading cause for the spread of foodborne illnesses in the foodservice industry. A series of complex motivational interventions must be employed to permanently change the behavior of workers, to increase their compliance and sustain appropriate levels of proper hand hygiene. Unlike the healthcare industry, which uses large, costly multi-modal behavior modification strategies, the foodservice industry must deploy rapid, cost-efficient strategies that take into account a high employee turnover rate and diverse demographics. This paper reviews the current motivational models used in the foodservice industry and examines the habitual nature of complying with good hand hygiene. It also reviews current techniques to increase hand hygiene compliance using clues from three of the five basic senses (sight, hearing, and smell) and two mechanisms (context-bridging and disgust). Lastly, the current model for habit intervention is evaluated, and its possible applications in the foodservice industry with additional reminders are accessed. We believe that this review will provide foodservice managers the background, theoretical basis and practical applications for making long-term changes in their employees on this and similar critical behaviors in foodservice. 相似文献
278.
Tian Xie Ziliang Yang Guanyu Dai Kaixiao Yan Yuan Tian Dan Zhao Huawei Zou Fei Deng Xiaolei Chen Quan Yuan 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(3):668-673
Chronic kidney disease has become a worldwide public health problem, and it negatively affects oral health. However, the data of the hemodialysis (HD) patients in Chinese population is unknown. This study was aimed to evaluate the dental health status and oral hygiene behavior of the HD patients in China. Patients undergoing HD therapy at two hospitals were asked to finish a questionnaire and receive dental examination (DMF‐T). A total of 306 patients, aged 24–88 (58.09 ± 14.06), took part in this study. Although majority of the patients (77.78%) brushed their teeth at least twice a day, few (less than 5%) had ever used dental floss or mouthwash. More than half of the patients have not visited a dentist since the commencement of HD therapy. The dental examination showed that DMF‐T was 9.63 ± 7.54, and the number of filled teeth (F‐T) was only 0.70 ± 1.48. Moreover, the average caries restoration ratio and replacement index were 17.57% and 32.59%, respectively. HD therapy seems to prevent patients from visiting a dentist, and there is a great need for dental treatment for Chinese HD patients. 相似文献
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Public service psychologists have led in the systematic use of new approaches to assessment, diagnosis, therapeutic interventions, and organizational management of mental and physical disorders. Outstanding examples include the MMPI and its successor developed at the University of Minnesota; elaboration of its 2-point code types and additional clinical scales at VA Medical Centers; David Wechsler’s work on intelligence and memory measurement at Bellevue Hospital, New York; early adoption of group therapy, early development of family therapy, token economies, and adult mental hygiene clinics; and finally the impetus for the development of accreditation in professional psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献