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971.
根据色斑的形成机理,采用相应的天然草本植物提取物淡化色斑。根据细胞内黑色素形成机理,选用适当抑制剂。减少黑色素的过量生成,防止皮肤表皮的继续黑化,提出美白与祛斑化妆品的合理配制方法。  相似文献   
972.
溪源泄洪洞出口位于闽江之上,为分析泄洪洞出口处的设计水位,采用设计流量和水位流量关系推求法及实测水位资料推求法两种方法对工程设计水位进行计算,经过合理性分析,工程所在地近年水位变化剧烈,采用设计流量和水位流量关系推求法更符合现状情况,为工程建设提供可靠的设计成果。  相似文献   
973.
介绍 4 0 0 kt/ a硫酸系统电除雾器总体结构及工艺设计参数 ,投入运行后 ,除雾效率低 ,介绍对存在问题的分析及解决过程 ,并介绍 2点成功经验  相似文献   
974.
聚丙烯管材加工性能研究   总被引:3,自引:0,他引:3  
研究了无规共聚聚丙烯管材(PP-R)管材专用料的加工工艺,PP管材加工设备的选用及模具设计参数,并对PP-R管材焊接工艺进行了研究,结果表明,合适的加工工艺条件,成型设备及焊接工艺能够保证PP-R管材的质量。  相似文献   
975.
本文介绍了复合材料管件(无人机尾撑杆)的结构与铺层设计、基体树脂选择和成型工艺以及性能测试等内容。  相似文献   
976.
加快创新开发,开拓聚氯乙烯压力管道系统的新局面   总被引:5,自引:0,他引:5  
张玉川 《塑料》2006,35(6):54-64
近年来聚氯乙烯管道取得了重大进步。PVC-M管材(改性聚氯乙烯管材)、PVC-O管材(取向聚氯乙烯管材)兼有非凡的强度和韧度,和传统的硬聚氯乙烯管材比可以采用较高的设计应力,显著地节约材料。  相似文献   
977.
占晓初  石荣国 《中国陶瓷》2007,43(10):74-76
青花红绿彩作为加彩器的一种,比传统的观点早一个朝代,根据明中青花红绿彩盖罐结合最新的窑址考古成果,得出元代的窑炉设计和釉面配方的缺陷,使元代青花红绿彩的生产和存世极少,明官窑中由于斗彩的出现,青花红绿彩在民间一直沿烧。与元代风格相近,只是到了后期风格才大变。  相似文献   
978.

Introduction

A usability test was employed to evaluate two medical software applications at an expert conference setting. One software application is a medical diagnostic tool (electrocardiogram [ECG] viewer) and the other is a medical research tool (electrode misplacement simulator [EMS]). These novel applications have yet to be adopted by the healthcare domain, thus, (1) we wanted to determine the potential user acceptance of these applications and (2) we wanted to determine the feasibility of evaluating medical diagnostic and medical research software at a conference setting as opposed to the conventional laboratory setting.

Methods

The medical diagnostic tool (ECG viewer) was evaluated using seven delegates and the medical research tool (EMS) was evaluated using 17 delegates that were recruited at the 2010 International Conference on Computing in Cardiology. Each delegate/participant was required to use the software and undertake a set of predefined tasks during the session breaks at the conference. User interactions with the software were recorded using screen-recording software. The ‘think-aloud’ protocol was also used to elicit verbal feedback from the participants whilst they attempted the pre-defined tasks. Before and after each session, participants completed a pre-test and a post-test questionnaire respectively.

Results

The average duration of a usability session at the conference was 34.69 min (SD = 10.28). However, taking into account that 10 min was dedicated to the pre-test and post-test questionnaires, the average time dedication to user interaction of the medical software was 24.69 min (SD = 10.28). Given we have shown that usability data can be collected at conferences, this paper details the advantages of conference-based usability studies over the laboratory-based approach. For example, given delegates gather at one geographical location, a conference-based usability evaluation facilitates recruitment of a convenient sample of international subject experts. This would otherwise be very expensive to arrange. A conference-based approach also allows for data to be collected over a few days as opposed to months by avoiding administration duties normally involved in laboratory based approach, e.g. mailing invitation letters as part of a recruitment campaign.Following analysis of the user video recordings, 41 (previously unknown) use errors were identified in the advanced ECG viewer and 29 were identified in the EMS application. All use errors were given a consensus severity rating from two independent usability experts. Out of a rating scale of 4 (where 1 = cosmetic and 4 = critical), the average severity rating for the ECG viewer was 2.24 (SD = 1.09) and the average severity rating for the EMS application was 2.34 (SD = 0.97). We were also able to extract task completion rates and times from the video recordings to determine the effectiveness of the software applications. For example, six out of seven tasks were completed by all participants when using both applications. This statistic alone suggests both applications already have a high degree of usability. As well as extracting data from the video recordings, we were also able to extract data from the questionnaires. Using a semantic differential scale (where 1 = poor and 5 = excellent), delegates highly rated the ‘responsiveness’, ‘usefulness’, ‘learnability’ and the ‘look and feel’ of both applications.

Conclusion

This study has shown the potential user acceptance and user-friendliness of the novel EMS and the ECG viewer applications within the healthcare domain. It has also shown that both medical diagnostic software and medical research software can be evaluated for their usability at an expert conference setting. The primary advantage of a conference-based usability evaluation over a laboratory-based evaluation is the high concentration of experts at one location, which is convenient, less time consuming and less expensive.  相似文献   
979.
Vibration mechanism is good candidates to be used as actuation system in small robots. However, mini fabrication of small electrical and mechanical drives is a challenging issue. Moreover, no analytical model for motion analysis of vibration driven robots is devised. In this paper, a small robot is developed. To setup a low-cost robot, cell phone vibrators are employed as actuation mechanism. Motion principle of the robot is analytically obtained and appropriate mechanical and electronic derives are designed. Some technical tips are employed to reduce the size of the robot. The obtained model was evaluated by simulations in MSC.ADAMS as well as some standard experiments on a real robot named Rizeh. Moreover, the robot is tested in a line following task, as a typical task for mobile robots.  相似文献   
980.
Catalytic Materials for High-Temperature Combustion   总被引:15,自引:0,他引:15  
Catalytic combustion, as an alternative to conventional thermal combustion, has received considerable attention during the past decade. Research efforts have been promoted by the need to meet governmental demands concerning pollution and the wish to use energy sources more efficiently. The two main advantages offered by catalytic combustors over flame combustors apply to these goals:
  1. Catalytic combustion can be carried out over a wide range of fuel concentrations in air and at low temperatures.
  2. These low temperatures result in attaining NO, emission levels substantially lower than possible with conventional combustors.
  相似文献   
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