Based on analyzing the overlap appearance of random winding, basic principles of ribbon-free random winding and parametric selections for anti-overlap are discussed. The ribbon-free random winding control system and i...Based on analyzing the overlap appearance of random winding, basic principles of ribbon-free random winding and parametric selections for anti-overlap are discussed. The ribbon-free random winding control system and its related hardware construction as well as its software design are introduced by applying PCC technology to high speed spinning machine of synthetic filament.展开更多
Sea-crossing bridges are affected by random wind–wave–undercurrent coupling loads, due to the complex marine environment. The dynamic response of long-span Rail-cum-Road cable-stayed bridges is particularly severe u...Sea-crossing bridges are affected by random wind–wave–undercurrent coupling loads, due to the complex marine environment. The dynamic response of long-span Rail-cum-Road cable-stayed bridges is particularly severe under their influence, potentially leading to safety problems. In this paper, a fluid–structure separation solution method is implemented using Ansys–Midas co-simulation, in order to solve the above issues effectively while using less computational resources. The feasibility of the method is verified by comparing the tower top displacement response with relevant experimental data. From time and frequency domain perspectives, the displacement and acceleration responses of the sea-crossing Rail-cum-Road cable-stayed bridge influenced by wave-only, wind–wave, and wind–wave–undercurrent coupling are comparatively studied. The results indicate that the displacement and acceleration of the front bearing platform top are more significant than those of the rear bearing platform. The dominant frequency under wind–wave–undercurrent coupling is close to the natural vibration frequencies of several bridge modes,such that wind–wave–undercurrent coupling is more likely to cause a resonance effect in the bridge. Compared with the wave-only and wind–wave coupling, wind–wave–undercurrent coupling can excite bridges to produce larger displacement and acceleration responses: at the middle of the main girder span, compared with the wave-only case, the maximum displacement in the transverse bridge direction increases by 23.58% and 46.95% in the wind–wave and wind–wave–undercurrent coupling cases, respectively;at the tower top, the variation in the amplitude of the displacement and acceleration responses of wind–wave and wind–wave–undercurrent coupling are larger than those in the wave-only case, where the acceleration change amplitude of the tower top is from-0.93 to 0.86 m/s^(2) in the waveonly case, from-2.2 to 2.1 m/s^(2) under wind–wave coupling effect, and from-2.6 to 2.65 m/s^(2) under wind–wave–undercurrent coupling effect, indicating that the tower top is mainly affected by wind loads, but wave and undercurrent loads cannot be neglected.展开更多
OBJECTIVE: To observe the curative effect of Jinye Baidu granule in the treatment of fever and swollen and sore throat caused by wind-warmth lung-heat disease(heat in the lung-wei) to further identify the indications....OBJECTIVE: To observe the curative effect of Jinye Baidu granule in the treatment of fever and swollen and sore throat caused by wind-warmth lung-heat disease(heat in the lung-wei) to further identify the indications.METHODS: This randomized, double-blind, parallel, controlled trial will include patients with acute upper respiratory infection and wind-warmth lung-heat disease(heat in the lung-wei). Patientswith serious bacterial infection(white blood cell count > 12 × 10~9, neutrophils > 80%) will be excluded. Patients will be divided into three categories(blocks) according to their condition: fever only, a swollen and sore throat, and combined fever plus a swollen and sore throat. Patients within each of the three blocks will be further divided into a treatment group and a control group via stratified blocked randomization. The treatment group will be treated with Jinye Baidu granule, and the control group will be treated with Fufang Shuanghua granule. The primary outcome measure will be body temperature recovery time for patients with fever, throat symptom score for patients with a swollen and sore throat, and body temperature recovery time and throat symptom score for patients with combined fever plus a swollen and sore throat. Routine blood testing, urine testing, liver function, kidney function and ECG data of all patients will be collected as safety indices before and after enrollment, and adverse events will be recorded during the whole trial course.CONCLUSION: This study protocol will include stratified block analysis according to patients' symptoms, and identify the accurate clinical indications of Jinye Baidu granule. It will also enable safety evaluation from laboratory indices and adverse events, which will provide reliable evidence for clinical treatment.展开更多
A frequency-domain algorithm is presented for the dynamic analysis of guyed masts. By introducing a four-degrees-of-freedom model of a suspended cable, guyed masts are simpli?ed as an equivalent cable-beam model. Th...A frequency-domain algorithm is presented for the dynamic analysis of guyed masts. By introducing a four-degrees-of-freedom model of a suspended cable, guyed masts are simpli?ed as an equivalent cable-beam model. Then, based on the discrete random vibration theory, recurrence formulas for the statistical moments of the wind-induced behavior of guyed masts are developed with the wind load treated as ?ltered white noise excitation. The dynamic analysis of a two-level guyed mast has been illustrated. Finally, results from a wind-tunnel experiment of guyed mast are used to testify the theory developed in this paper.展开更多
风力机组的运行状态关乎风电企业的经济效益,低效机组判定对风电场效能提升具有重要意义。现有研究多聚焦单机风电功率特性等运行状态,针对风电场整体效能评估的研究较少。为此,提出一种基于聚类和随机森林的低效风力机组判定方法。首...风力机组的运行状态关乎风电企业的经济效益,低效机组判定对风电场效能提升具有重要意义。现有研究多聚焦单机风电功率特性等运行状态,针对风电场整体效能评估的研究较少。为此,提出一种基于聚类和随机森林的低效风力机组判定方法。首先基于数据采集与监视控制系统(supervisory control and data acquisition,SCADA)获取机组运行数据,引入风能捕获差异率和发电输出差异率指标,对数据进行聚类后添加低效判定值。其次应用随机森林分类算法对低效判定值进行验证分析,最后根据机组低效判定值均值结果识别低效机组。为验证所提方法的准确性和有效性,根据某风电场23台风力机组的全年运行数据进行分析,结果表明该方法能够精确有效识别低效风力机组,能够为风电场针对性技改提供指导。展开更多
文摘Based on analyzing the overlap appearance of random winding, basic principles of ribbon-free random winding and parametric selections for anti-overlap are discussed. The ribbon-free random winding control system and its related hardware construction as well as its software design are introduced by applying PCC technology to high speed spinning machine of synthetic filament.
文摘Sea-crossing bridges are affected by random wind–wave–undercurrent coupling loads, due to the complex marine environment. The dynamic response of long-span Rail-cum-Road cable-stayed bridges is particularly severe under their influence, potentially leading to safety problems. In this paper, a fluid–structure separation solution method is implemented using Ansys–Midas co-simulation, in order to solve the above issues effectively while using less computational resources. The feasibility of the method is verified by comparing the tower top displacement response with relevant experimental data. From time and frequency domain perspectives, the displacement and acceleration responses of the sea-crossing Rail-cum-Road cable-stayed bridge influenced by wave-only, wind–wave, and wind–wave–undercurrent coupling are comparatively studied. The results indicate that the displacement and acceleration of the front bearing platform top are more significant than those of the rear bearing platform. The dominant frequency under wind–wave–undercurrent coupling is close to the natural vibration frequencies of several bridge modes,such that wind–wave–undercurrent coupling is more likely to cause a resonance effect in the bridge. Compared with the wave-only and wind–wave coupling, wind–wave–undercurrent coupling can excite bridges to produce larger displacement and acceleration responses: at the middle of the main girder span, compared with the wave-only case, the maximum displacement in the transverse bridge direction increases by 23.58% and 46.95% in the wind–wave and wind–wave–undercurrent coupling cases, respectively;at the tower top, the variation in the amplitude of the displacement and acceleration responses of wind–wave and wind–wave–undercurrent coupling are larger than those in the wave-only case, where the acceleration change amplitude of the tower top is from-0.93 to 0.86 m/s^(2) in the waveonly case, from-2.2 to 2.1 m/s^(2) under wind–wave coupling effect, and from-2.6 to 2.65 m/s^(2) under wind–wave–undercurrent coupling effect, indicating that the tower top is mainly affected by wind loads, but wave and undercurrent loads cannot be neglected.
基金Supported by the Ninth Scientific Research Foundation of Institute of Basic Research in Clinical Medicine,China Academy of Chinese Medical Sciences(No.Z0406)the Research Project of World Federation of Chinese Medicine Societies(SCEPCM12E001)the Special Research Project of Traditional Chinese Medicines by the State Administration of Traditional Chinese Medicine(No.201507003-8)
文摘OBJECTIVE: To observe the curative effect of Jinye Baidu granule in the treatment of fever and swollen and sore throat caused by wind-warmth lung-heat disease(heat in the lung-wei) to further identify the indications.METHODS: This randomized, double-blind, parallel, controlled trial will include patients with acute upper respiratory infection and wind-warmth lung-heat disease(heat in the lung-wei). Patientswith serious bacterial infection(white blood cell count > 12 × 10~9, neutrophils > 80%) will be excluded. Patients will be divided into three categories(blocks) according to their condition: fever only, a swollen and sore throat, and combined fever plus a swollen and sore throat. Patients within each of the three blocks will be further divided into a treatment group and a control group via stratified blocked randomization. The treatment group will be treated with Jinye Baidu granule, and the control group will be treated with Fufang Shuanghua granule. The primary outcome measure will be body temperature recovery time for patients with fever, throat symptom score for patients with a swollen and sore throat, and body temperature recovery time and throat symptom score for patients with combined fever plus a swollen and sore throat. Routine blood testing, urine testing, liver function, kidney function and ECG data of all patients will be collected as safety indices before and after enrollment, and adverse events will be recorded during the whole trial course.CONCLUSION: This study protocol will include stratified block analysis according to patients' symptoms, and identify the accurate clinical indications of Jinye Baidu granule. It will also enable safety evaluation from laboratory indices and adverse events, which will provide reliable evidence for clinical treatment.
基金Project supported by the National Natural Science Foundation of China (No. 59778030).
文摘A frequency-domain algorithm is presented for the dynamic analysis of guyed masts. By introducing a four-degrees-of-freedom model of a suspended cable, guyed masts are simpli?ed as an equivalent cable-beam model. Then, based on the discrete random vibration theory, recurrence formulas for the statistical moments of the wind-induced behavior of guyed masts are developed with the wind load treated as ?ltered white noise excitation. The dynamic analysis of a two-level guyed mast has been illustrated. Finally, results from a wind-tunnel experiment of guyed mast are used to testify the theory developed in this paper.
文摘风力机组的运行状态关乎风电企业的经济效益,低效机组判定对风电场效能提升具有重要意义。现有研究多聚焦单机风电功率特性等运行状态,针对风电场整体效能评估的研究较少。为此,提出一种基于聚类和随机森林的低效风力机组判定方法。首先基于数据采集与监视控制系统(supervisory control and data acquisition,SCADA)获取机组运行数据,引入风能捕获差异率和发电输出差异率指标,对数据进行聚类后添加低效判定值。其次应用随机森林分类算法对低效判定值进行验证分析,最后根据机组低效判定值均值结果识别低效机组。为验证所提方法的准确性和有效性,根据某风电场23台风力机组的全年运行数据进行分析,结果表明该方法能够精确有效识别低效风力机组,能够为风电场针对性技改提供指导。
