MAGNETIC TRIGGER FOR AUTOMATIC PUMPING SAMPLERS1

ABSTRACT: A stage-activated triggering device was developed for automatic pumping samplers. The device consists of a proximity switch and ten magnets mounted radially at equal intervals on a plexiglass disk. The triggering device allows discrete sampling of stream water at 3.0 cm intervals of stage. The trigger proved dependable during two years of use at three headwater streams in the Ouachita Mountains of southeastern Oklahoma.     

电梯制动器机械装置提起（或释放）验证的研究

为确保电梯制动器检测开关能够准确检测电梯制动器机械装置提起（或释放）的异常,消除异常造成的危险情况,结合电梯制动器的型式和检测开关的动作原理,对各种检测开关接线方式进行分析,针对制动器的型式提出了合理的制动器检测开关接线方式。研究结果表明:直压式制动器可用1个通断状态的检测开关对其机械装置的提起（或释放）进行验证,但应在电梯的主板上设置2个检测点;杠杆式鼓式制动器应用具备2个通断状态的检测开关对其机械装置的提起（或释放）进行验证,且应采用常开并联或常闭串联的方式检测制动器机械装置的释放,采用常闭并联和常开串联的方式检测制动器机械装置的提起。     

Effect of posture on forces and moments measured in a Hybrid III ATD lower leg

Objective: Anthropomorphic test devices (ATDs) are used to assess real injury risk to occupants of vehicles during injurious events. In the lower leg, values from load cells are compared to injury criteria developed in cadaveric studies. These criteria are typically developed with the leg in a neutral posture, whereas the ATD may assume a wide range of postures during safety evaluation tests. The degree to which the initial posture of an ATD has an effect on the measured forces and moments in the lower leg is unknown.

Methods: A Hybrid III ATD lower leg was impacted in a range of postures under conditions representing a crash test, and peak axial force and adjusted tibia index injury measures were evaluated. Ankle posture was varied in 5° increments using a custom-made footplate, and dorsi/plantarflexion (20° DF to 20° PF) and in/eversion (20° IV to 5° EV) were evaluated. Tibia angle was also varied (representing knee flexion/extension) by ±10° from neutral.

Results: Peak axial force was not affected by ankle flexion or tibia angulation. Adjusted tibia index was lowest for plantarflexion, as well as for tibia angles representative of knee extension. Both peak axial force and adjusted tibia index were lowest for postures of great inversion and were highest in neutral or near-neutral postures.

Conclusions: The range of postures tested herein spanned published injury criteria and thus would have made the difference between pass and fail in a safety evaluation. In/eversion had the largest influence on injury metrics, likely due to the change in axial stiffness and altered impact durations in these postures. Results suggest increased injury risk at neutral or near-neutral postures, whereas previous cadaveric studies have suggested that in/eversion does not influence injury risk. It is unclear whether the ATD appropriately represents the natural lower leg for impacts in out-of-position testing. Great care must be taken when initially positioning ATDs for safety evaluations, because small perturbations in posture were shown herein to have large effects on the measured injury risk using this tool.     

Comparison of current ATDs with Chinese adults in anthropometry

Objective: Crash test dummies are full-scale anthropomorphic test devices (ATDs) that simulate the dimensions, weight proportions, and articulation of the human body and are used to measure human injury potential in vehicle crashes. The Hybrid III dummy family, which is widely used currently, takes selected percentiles of anthropometry dimensions of U.S. adults as design references. The objective of this study was to assess the difference in anthropometry between Chinese adults and the currently used dummy.

Methods: Based on the Chinese National Physical Fitness Surveillance of the year 2000, 2005, 2010 and National Standard of China GB/T 10000–1988, a series of anthropometric parameters for Chinese adults were obtained, and data analysis was conducted between Chinese adults and ATDs that are currently used.

Results: The comparison revealed distinct anthropometric difference between ATDs and Chinese adults. Based on the latest data, median Chinese females were about 2.6% lower in stature and about 8.03% lower in body weight than the ATD design targets. Similarly, median Chinese males were about 3.48% shorter and weighed 11.89% less than the ATD design targets.

Conclusions: Although the anthropometric differences between Chinese adults and the Hybrid III ATD specifications were modest and growing smaller, it is advisable to take the differences in anthropometry between ATDs and Chinese adults into consideration when developing new vehicles in China to provide effective protection specifically for Chinese occupants.     

产品电子元器件封装及加固技术

为保证电子器件的环境适应性和可靠性要求,在传统"三防"的基础上,着重论述了产品电子元器件的封装、加固技术。方法介绍了常用的封装加固材料的性能,针对不同的器件,规定了封装加固工艺流程,其中针对导引头提出了两种封装材料,其耐冲击指标达到8×103g~20×103g。为三防设计及选材提供了依据,对工艺防护提供了实际经验和技术要求,从而避免缺陷导致的质量问题。电子元器件封装加固技术,能够提高电子产品的防护性能,具有一定指导作用。     

水质自动监测站运营外包的质量管理研究

围绕水质自动监测站运营外包的质量管理,概述了水站系统运行过程中的质量保证和质量控制,在分析环境保护监测站在政府外包监测任务中所起作用的基础上,通过项目服务需求的编写、现场质量监督、质量控制措施、质量评价和运用智能化软件提高质控效率等五方面详述了关于水质自动监测站运营外包质量管理的关键点,并且重点阐述了对水站运维服务的质量监督和评价,以期为政府及其下属环境保护监测站关于环境监测任务外包的质量管理方面提供一定的借鉴.     

基于SAE-ARP958环天线校准技术研究

目的介绍基于SAE-ARP958环天线校准技术,研究提高该校准精确性的方法,为精确监测电磁环境提供保障。方法研制一套基于SAE-ARP958环天线的校准装置,提出采用直径分别为30,10,4 cm的三个发射环天线作为磁场发生装置的校准方案,并利用对比测试的方法对校准方案进行优化。结果优化后的校准方案能够实现环天线的精确校准。结论基于SAE-ARP958环天线校准方法具有不受待校环尺寸限制的优点,而且精确性高,值得向具有较多不同尺寸的环天线用户推广。     

溜石坡崩塌体运动过程与防治措施研究*

为降低中巴公路沿线溜石灾害风险,以中巴公路K777桩处溜石坡为研究对象,定性分析溜石崩塌体运动特征并设计格栅挡墙防护结构。采用有限差分与离散元耦合方法对溜石灾害进行数值模拟,定量分析溜石崩塌体运动状态及公路挡墙动力冲击响应。结果表明:不同粒径下溜石平均速度变化趋势相同,溜石崩塌体运动速度与溜石粒径呈正相关,溜石在自然条件下对公路挡墙冲击集中且受力较大,通过布置格栅挡墙可降低公路挡墙受力,分散溜石冲击,有效拦截大粒径溜石,降低溜石灾害影响。在相同格栅挡墙孔径下,降速效果与溜石粒径呈负相关。可通过考察溜石坡实际情况设计格栅挡墙尺寸,降低中巴公路沿线溜石灾害风险。     

城市生活垃圾中转站举升装置设计与应用

对地平式城市垃圾中转站的 3种举升装置进行了详细分析 ,指出了其存在的问题 ,提出了一种新型的链条式城市垃圾中转站举升装置 ,它结构紧凑 ,运行平稳可靠 ,成本低 ,噪音小 ,节能省电 ,是垃圾中转站新型优选产品 ,现已成功应用于环卫工程中