With the application of energy-saving, environmental and durable LED lighting products, the reliability testing has become a pivot point for the large scale industrialization and popularization. The paper briefly intr...With the application of energy-saving, environmental and durable LED lighting products, the reliability testing has become a pivot point for the large scale industrialization and popularization. The paper briefly introduces two methods to be respectively applied in the accelerated depreciatinn lesting for the luminous flex of LED lighting products and the life of outdoor LED-driving power, which can sharply shorten the time for lifetime lest. providing references for the LED lighting products＇ reliability evaluation.展开更多
To estimate a compressive strength from existing concrete structures by core drilling are usually gathered with a diameter specimen of 100 mm or three times of maximum coarse aggregate size and examined by uniaxial co...To estimate a compressive strength from existing concrete structures by core drilling are usually gathered with a diameter specimen of 100 mm or three times of maximum coarse aggregate size and examined by uniaxial compressive strength （UCS）. It is relatively difficult to gather a large sized core, and a pit place will be limited by main members. To get an alternative solution with smaller specimen, point load test （PLT） has been sele,：ted which is a simple test and widely accepted in rock materials research, but relatively new in concrete. The reliability of PLT is evaluated by extracting a lot of core drilled specimen from ready mixed concrete blocks with maximum coarse aggregate size, G of 20 mm in representative of architectural structures and 40 mm in representative of civil structures on the range of concrete grade from 16 to 50. Compressive strengths were classified into general categories, conversion factors were determined, and scattering characteristics were also investigated. The relationship between point load index （Is） and compressive strength of concrete core specimen （fcc） can be written as linear approximation as fcc = k.Is- C.展开更多
In the past,only one performance parameter was considered in the reliability estimation of micro-electro-mechanical system (MEMS) accelerometers,resulting in a one-sided reliability evaluation. Aiming at the failure c...In the past,only one performance parameter was considered in the reliability estimation of micro-electro-mechanical system (MEMS) accelerometers,resulting in a one-sided reliability evaluation. Aiming at the failure condition of large range MEMS accelerometers in high temperature environment,the corresponding accelerated degradation test is designed. According to the degradation condition of zero bias and scale factor,multiple dependent reliability estimation of large range MEMS accelerometers is carried out. The results show that the multiple dependent reliability estimation of the large range MEMS accelerometers can improve the accuracy of the estimation and get more accurate results.展开更多
OBJECTIVE: To evaluate the quality of randomized controlled trials(RCTs) testing the efficacy of warming needle moxibustion on knee osteoarthritis(KOA).METHODS: Nine databases were searched systematically including: t...OBJECTIVE: To evaluate the quality of randomized controlled trials(RCTs) testing the efficacy of warming needle moxibustion on knee osteoarthritis(KOA).METHODS: Nine databases were searched systematically including: the Cochrane Library(1/1993-10/2012), Pub Med(1/1980-10/2012), EMBASE(1/1990-10/2012), SCI Expanded(1/1986-10/2012), Science Direct(1/1979-10/2012), Chinese Biomedical Literature Database disc(1/1978-10/2012), China National Knowledge Infrastructure Database(1/1979-10/2012), China Science and Technology Journal Database(a full text issue database of China, 1/1989-10/2012), and Wanfang Database(a full text issue database of China, 1/1990-10/2012). Traditional reference retrieval was also conducted. Language was limited to Chinese and English. We identified 37 RCTs that used warming needle moxibustion as an intervention and they were assessed with the Consolidated Standards for Reporting of Trials Statement 2010(CONSORT 2010) and Standards for Reporting Interventions Controlled Trials of Acupuncture 2010(STRICTA 2010).RESULTS: Of the 37 reports, only seventeen(45.95%) mentioned the random allocation of sequence methods, nine used unacceptable methods, and only one(2.70%) gave the description of the mechanism of allocation concealment. One study(2.70%) mentioned blinding, one(2.70%) had a sample size calculation, and twenty-three(62.16%) used reasonable statistical methods. Thirteen(35.14%) described the background and reason for the RCTs, three(8.11%) gave a description of lost or eliminated patients, and two(5.41%) reported accidental situations. Only three(8.11%)gave analysis of the RCT limitations. No report mentioned intentional analysis.CONCLUSION: The quality of the RCTs assessed in this study was from moderate to low. The design of RCTs, the methods of statistical analysis, and the description of reports information needs to be improved. CONSORT 2010 and STRICTA 2010 should be used to standardize the reporting of acupuncture RCTs in the future.展开更多
文摘With the application of energy-saving, environmental and durable LED lighting products, the reliability testing has become a pivot point for the large scale industrialization and popularization. The paper briefly introduces two methods to be respectively applied in the accelerated depreciatinn lesting for the luminous flex of LED lighting products and the life of outdoor LED-driving power, which can sharply shorten the time for lifetime lest. providing references for the LED lighting products＇ reliability evaluation.
文摘To estimate a compressive strength from existing concrete structures by core drilling are usually gathered with a diameter specimen of 100 mm or three times of maximum coarse aggregate size and examined by uniaxial compressive strength （UCS）. It is relatively difficult to gather a large sized core, and a pit place will be limited by main members. To get an alternative solution with smaller specimen, point load test （PLT） has been sele,：ted which is a simple test and widely accepted in rock materials research, but relatively new in concrete. The reliability of PLT is evaluated by extracting a lot of core drilled specimen from ready mixed concrete blocks with maximum coarse aggregate size, G of 20 mm in representative of architectural structures and 40 mm in representative of civil structures on the range of concrete grade from 16 to 50. Compressive strengths were classified into general categories, conversion factors were determined, and scattering characteristics were also investigated. The relationship between point load index （Is） and compressive strength of concrete core specimen （fcc） can be written as linear approximation as fcc = k.Is- C.
文摘In the past,only one performance parameter was considered in the reliability estimation of micro-electro-mechanical system (MEMS) accelerometers,resulting in a one-sided reliability evaluation. Aiming at the failure condition of large range MEMS accelerometers in high temperature environment,the corresponding accelerated degradation test is designed. According to the degradation condition of zero bias and scale factor,multiple dependent reliability estimation of large range MEMS accelerometers is carried out. The results show that the multiple dependent reliability estimation of the large range MEMS accelerometers can improve the accuracy of the estimation and get more accurate results.
基金Supported by Study on the Mechanism of Chiropractic Therapy Why It Can Adjust Gastrointestinal Function(National Natural Science Foundation of China,No.81273868)The Acupuncture Clinical Practice Guideline of Knee Arthritis(the Standardization Project of State Administrative of Traditional Chinese Medicine,No.ZYYS2009-0009-9)
文摘OBJECTIVE: To evaluate the quality of randomized controlled trials(RCTs) testing the efficacy of warming needle moxibustion on knee osteoarthritis(KOA).METHODS: Nine databases were searched systematically including: the Cochrane Library(1/1993-10/2012), Pub Med(1/1980-10/2012), EMBASE(1/1990-10/2012), SCI Expanded(1/1986-10/2012), Science Direct(1/1979-10/2012), Chinese Biomedical Literature Database disc(1/1978-10/2012), China National Knowledge Infrastructure Database(1/1979-10/2012), China Science and Technology Journal Database(a full text issue database of China, 1/1989-10/2012), and Wanfang Database(a full text issue database of China, 1/1990-10/2012). Traditional reference retrieval was also conducted. Language was limited to Chinese and English. We identified 37 RCTs that used warming needle moxibustion as an intervention and they were assessed with the Consolidated Standards for Reporting of Trials Statement 2010(CONSORT 2010) and Standards for Reporting Interventions Controlled Trials of Acupuncture 2010(STRICTA 2010).RESULTS: Of the 37 reports, only seventeen(45.95%) mentioned the random allocation of sequence methods, nine used unacceptable methods, and only one(2.70%) gave the description of the mechanism of allocation concealment. One study(2.70%) mentioned blinding, one(2.70%) had a sample size calculation, and twenty-three(62.16%) used reasonable statistical methods. Thirteen(35.14%) described the background and reason for the RCTs, three(8.11%) gave a description of lost or eliminated patients, and two(5.41%) reported accidental situations. Only three(8.11%)gave analysis of the RCT limitations. No report mentioned intentional analysis.CONCLUSION: The quality of the RCTs assessed in this study was from moderate to low. The design of RCTs, the methods of statistical analysis, and the description of reports information needs to be improved. CONSORT 2010 and STRICTA 2010 should be used to standardize the reporting of acupuncture RCTs in the future.
