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On Quality and Test Training of English Teaching
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作者 薛永 《徐州教育学院学报》 1999年第3期82-83,共2页
During several decades of English teaching, we have achieved very much. But at the same time we have focused on test training too much. In order to train the developing-both-in-all- round - and - fullt students who ca... During several decades of English teaching, we have achieved very much. But at the same time we have focused on test training too much. In order to train the developing-both-in-all- round - and - fullt students who can suit to social need, we must raise the level of quality training. This article gives the result resulting in the test training and mentions the ways to quality train-ing. 展开更多
关键词 test trainING QUALITY trainING REASONS CHANGE
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Model tests on XCC-piled embankment under dynamic train load of high-speed railways 被引量:7
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作者 Niu Tingting Liu Hanlong +1 位作者 Ding Xuanming Zheng Changjie 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2018年第3期581-594,共14页
Piled embankments,which offer many advantages,are increasingly popular in construction of high-speed railways in China.Although the performance of piled embankment under static loading is well-known,the behavior under... Piled embankments,which offer many advantages,are increasingly popular in construction of high-speed railways in China.Although the performance of piled embankment under static loading is well-known,the behavior under the dynamic train load of a high-speed railway is not yet understood.In light of this,a heavily instrumented piled embankment model was set up,and a model test was carried out,in which a servo-hydraulic actuator outputting M-shaped waves was adopted to simulate the process of a running train.Earth pressure,settlement,strain in the geogrid and pile and excess pore water pressure were measured.The results show that the soil arching height under the dynamic train load of a high-speed railway is shorter than under static loading.The growth trend for accumulated settlement slowed down after long-term vibration although there was still a tendency for it to increase.Accumulated geogrid strain has an increasing tendency after long-term vibration.The closer the embankment edge,the greater the geogrid strain over the subsoil.Strains in the pile were smaller under dynamic train loads,and their distribution was different from that under static loading.At the same elevation,excess pore water pressure under the track slab was greater than that under the embankment shoulder. 展开更多
关键词 piled embankment model test dynamic train load of high-speed railways XCC-pile M-shaped wave
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The Importance of Professional Training for Test Writers
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作者 谭明华 《海外英语》 2016年第1期92-93,共2页
The purpose of this essay was to explore the importance of professional training for test writers and teachers as well.Since both testing and teaching are so closely interrelated that it's impossible to work in ei... The purpose of this essay was to explore the importance of professional training for test writers and teachers as well.Since both testing and teaching are so closely interrelated that it's impossible to work in either field without being constantly concerned with the other. Test writers need professional training to keep pace with emergence of new views of language teaching practice and the rapid change of social life, in order to make testing more authentic and more valid. 展开更多
关键词 PROFESSIONAL training for test WRITERS tests RELIABLE VALID
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A Full Mission Simulator of the Ship's Automated Electric Power System for Training and Competence Testing of Marine Engineers
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作者 Mykola Mukha 《Journal of Shipping and Ocean Engineering》 2017年第4期153-160,共8页
This article describes practical preparation of marine engineers on the full mission simulator complex of the ship's automated electrical power plant. A full mission simulator complex of the ship's automated power m... This article describes practical preparation of marine engineers on the full mission simulator complex of the ship's automated electrical power plant. A full mission simulator complex of the ship's automated power management system meets International Convention STCW (Standards of Training, Certification and Watchkeeping) 78 (with Manila amendments 2010) requirements in part of adequate reproduction of its operational modes corresponding to the actual configuration and layout of the ship's automated power management system with real consumers and typical loads. The simulator is fully consistent with the goals and objectives of the practical training, as well as the goals and objectives of proficiency testing engine department officers on issues of technical maintenance of real ship's equipment (high voltage installations included) and means of automation. The simulator's complex is designed for training and proficiency testing of cadets and students of maritime educational institutions, as well as training and proficiency testing of marine specialists (mechanics and electricians) by watch-keeping and maintenance of modem integrated automated control systems of ship's electric power plant and the individual ship electromechanical systems, including high-voltage systems. A simulator's complex provides adequate reproduction of operational situations on technical side of real ship electric and automation equipment provides training on monitoring, control and management diesel-generator sets in hand, semi-automatic and automatic modes of power station, control and management of electromechanical systems, as well as the set of tasks upon parameterization, visualization and etc. Besides number of combinations of monitoring, control and management tasks, the simulator's complex provides an opportunity to simulate various practical fault conditions. It allows students to focus on the work of automatic control system in emergency situations and to work out correct actions for a watch-keeper on searching, localizing of faults and troubleshooting of equipment. 展开更多
关键词 Full mission simulator ship's automated electric power system practical training and proficiency testing training coursessubjects.
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Methodology to Evaluate Fatigue Damage of High-Speed Train Welded Bogie Frames Based on On-Track Dynamic Stress Test Data 被引量:5
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作者 Guangxue Yang Meng Wang +1 位作者 Qiang Li Ran Ding 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第3期181-188,共8页
The current method of estimating the fatigue life of railway structures is to calculating the equivalent stress amplitude based on the measured stress data. However, the random of the measured data is not considered. ... The current method of estimating the fatigue life of railway structures is to calculating the equivalent stress amplitude based on the measured stress data. However, the random of the measured data is not considered. In this paper, a new method was established to compute the equivalent stress amplitude to evaluate the fatigue damage based on the measurable randomness, since the equivalent stress is the key parameter for assessment of structure fatigue life and load derivation. The equivalent stress amplitude of a high-speed train welded bogie frame was found to obey normal distribution under uniform operation route that verified by on-track dynamic stress data, and the proposed model is, in effect, an improved version of the mathematical model used to calculate the equivalent stress amplitude. The data of a long-term, on-track dynamic stress test program was analyzed to find that the normal distribution parameters of equivalent stress amplitude values differ across different operation route. Thus, the fatigue damage of the high-speed train welded bogie frame can be evaluated by the proposed method if the running schedule of the train is known a priori. The results also showed that the equivalent stress amplitude of the region connected to the power system is more random than in other regions of the bogie frame. 展开更多
关键词 Fatigue damage evaluation Equivalent STRESS amplitude On-track dynamic STRESS test Welded BOGIE frame of high-speed train
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应用Test.Lab进行高速车体线路模态试验 被引量:9
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作者 邱飞力 张立民 王学亮 《噪声与振动控制》 CSCD 2012年第2期67-70,共4页
针对高速列车的振动问题,通过线路模态试验进行车体结构模态参数研究,采用LMS test.lab振动噪声测试系统进行数据采集和分析后处理。基于环境激励模态试验方法及模态参数识别理论,运用PolyMax模态提取法,获取了车体的前三阶弹性模态参... 针对高速列车的振动问题,通过线路模态试验进行车体结构模态参数研究,采用LMS test.lab振动噪声测试系统进行数据采集和分析后处理。基于环境激励模态试验方法及模态参数识别理论,运用PolyMax模态提取法,获取了车体的前三阶弹性模态参数和对应的模态振型,为车体结构优化设计提供依据。 展开更多
关键词 振动与波 高速列车 模态试验 模态参数 振型
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基于Testcase Designer的列车运行控制系统测试方法的研究 被引量:2
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作者 陈黎洁 孙超 +1 位作者 卢利勇 贺红阳 《铁路计算机应用》 2017年第1期18-22,共5页
针对CTCS-3级列控系统的需求规范,结合欧洲列车运行控制系统(ETCS)的测试经验,研究基于Testcase Designer的CTCS-3级列控系统自动测试方法。Testcase Designer主要用于将测试案例模块化,通过优化编写流程,生成符合测试平台需求的测试序... 针对CTCS-3级列控系统的需求规范,结合欧洲列车运行控制系统(ETCS)的测试经验,研究基于Testcase Designer的CTCS-3级列控系统自动测试方法。Testcase Designer主要用于将测试案例模块化,通过优化编写流程,生成符合测试平台需求的测试序列,为测试项目的执行提供必要的关键数据点。同时,Testcase Designer可供存储、导出及发布。其测试案例中的关键输入输出接口(如BTM、TIU、RTM等)配置信息均已通过配置文件形式实现。以列控系统无线闭塞中心(RBC)切换场景为例,采用Testcase Designer编写该场景的测试案例。研究结果表明:Testcase Designer实现了功能特征、参考需求、测试步骤等元素的集成,编写的测试案例是合理的。 展开更多
关键词 CTCS-3级列控系统 测试案例 运营场景 RBC切换
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2万t重载组合列车充排风特性对纵向冲动影响分析
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作者 卢小永 田昊 +1 位作者 宋逸飞 郭嘉 《科学技术创新》 2025年第3期197-200,共4页
纵向冲动是影响大秦线重载组合列车运行安全的关键因素。分别利用全真制动试验台和列车空气制动与纵向力学仿真系统,开展2万t重载组合列车充排风试验和初制调速列车纵向力仿真试验,根据试验结果分析充排风特性对列车纵向力的影响。
关键词 重载列车 试验 空气制动 纵向冲动
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不同性别和中医体质规培生心肺耐力的差异性研究
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作者 朱丽梅 林佳 +2 位作者 吴孝旭 王可文 钟文亮 《医学新知》 2025年第1期41-47,共7页
目的基于中医体质学说,探索不同性别和体质规培生心肺耐力的差异性。方法选取2023年7月至2024年4月期间的南平市人民医院规培生,评估中医体质并进行心肺运动试验,分析不同性别、体质规培生峰值摄氧量(VO_(2peak))等指标的差异。结果共纳... 目的基于中医体质学说,探索不同性别和体质规培生心肺耐力的差异性。方法选取2023年7月至2024年4月期间的南平市人民医院规培生,评估中医体质并进行心肺运动试验,分析不同性别、体质规培生峰值摄氧量(VO_(2peak))等指标的差异。结果共纳入67例规培生,其中,男性20例(29.85%)、女性47例(70.15%);平和质21例(31.34%)、偏颇质46例(68.66%)。男性规培生[1.97(1.68,2.27)]VO_(2peak)高于女性规培生[1.38(1.17,1.52)],差异具有统计学意义(P<0.05)。平和质组规培生[1.57(1.32,1.88)]VO_(2peak)高于偏颇质组规培生[1.48(1.19,1.72)],但差异无统计学意义(P>0.05)。男性、女性规培生偏颇质组的VO_(2peak)均高于平和质组,但差异均无统计学意义(P>0.05)。不同类型偏颇质中,痰湿质、湿热质的VO_(2peak)较高。结论规培生中中医体质以偏颇质为主,不同性别VO_(2peak)存在差异,平和质规培生VO_(2peak)数值较偏颇质规培生高。 展开更多
关键词 中医体质 心肺运动试验 心肺耐力 规培生
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市域D型车辆气密性试验方法现状与展望
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作者 贾晓沛 杜文韬 《液压气动与密封》 2025年第1期119-121,共3页
针对市域D型车辆气密性试验标准和试验方法展开讨论,对传统车辆气密性试验方法进行总结并分析其优缺点。提出一种新的车辆气密性试验方法,并对该氦质谱气密性检测法原理及试验应用做了阐述,以及展望了市域D型车辆气密性试验的未来技术。
关键词 市域D型 气密性试验 试验标准 氦质谱检测法
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Effectiveness of a Training Program for Improving Public Health Nurses’ Attitudes and Confidence in Dealing with Men Who Have Sex with Men
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作者 Asuka Waki Yumiko H. Nishimura +3 位作者 Mieko Iwai Gaku Okamoto Mikiko Ito Yasuharu Hidaka 《Open Journal of Nursing》 2017年第2期169-184,共16页
Objective: This study examined the effect of an educational intervention on public health nurses’ attitudes and confidence in dealing with men who have sex with men (MSM). In Japan, HIV is primarily transmitted throu... Objective: This study examined the effect of an educational intervention on public health nurses’ attitudes and confidence in dealing with men who have sex with men (MSM). In Japan, HIV is primarily transmitted through sexual contact between men, and free HIV testing and counseling are provided by public health nurses. However, because of a lack of education, public health nurses do not often recognize the existence of MSM in daily life. Thus, improving public health nurses’ understanding of MSM is crucial. Methods: This study used a quasi-experimental design to examine public health nurses’ homophobia, confidence in dealing with MSM, and low awareness of MSM in daily life at pre-test, post-test, and 1 and 3 months follow-ups. The intervention comprised a 3-hour training session conducted between November 2012 and September 2013 in the Kinki region. Results: A total of 124 public health nurses participated in the training, 117 of which were allocated to the intervention group;182 public health nurses who did not participate in the training session were allocated to a control group. Homophobia scores had significantly decreased at post-test, and remained at that low level by the follow-up at 3 months (pre-test to post-test;p = 0.00, post-test to 1 month;p = 0.83, 1 month to 3 months;p = 0.64, pre-test to 3 months;p = 0.00). Confidence in dealing with MSM and recognition of MSM had significantly increased by post-test;these were also maintained by the follow-up at 3 months (pre-test to post-test;p = 0.0, post-test to 1month;p = 0.18, 1 to 3 months;p = 0.44, pre-test to 3 months;p = 0.0). Discussion: While the three-hour training session was short, it was effective for improving attitudes toward MSM and building confidence in dealing with them. 展开更多
关键词 MEN Who Have SEX with MEN PUBLIC Health NURSE HIV test training
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LDRA TestBed在CTCS2-200C扩展单元软件测试中的应用 被引量:1
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作者 周永健 范明 +1 位作者 张淼 赵东旭 《机车电传动》 北大核心 2016年第5期102-106,共5页
介绍了LDRA Test Bed软件测试工具和CTCS2-200C扩展单元,以CTCS2-200C为例,通过对软件进行静态和动态测试,参照EN 50128:2011标准,提高了整个软件开发生命周期中的各项验证和确认活动效率,降低了软件的风险。
关键词 软件测试 test BED EN 50128 CTCS2-200C扩展单元 列控车载系统
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Qualified “in shelter” dogs’ evaluation and training to promote successful dog-human relationships
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作者 Marilena Sticco Roberto Trentini Pia Lucidi 《Open Journal of Animal Sciences》 2011年第3期135-144,共10页
The phenomenon of dogs’ relinquishment in Italy has become a social evil, although many laws exist to regulate animal protection and lately, the act of abandonment has become criminalised (law n.189/2004, enforced by... The phenomenon of dogs’ relinquishment in Italy has become a social evil, although many laws exist to regulate animal protection and lately, the act of abandonment has become criminalised (law n.189/2004, enforced by law n.201/2010). Adoption from shelters seems to be the only way to have a controlled, microchipped population of dogs, as well as limiting confinement and euthanasia. After being asked to simplify the previous Ethotest ? version [13] by many shelter operators and veterinarians, the authors aimed at analyzing the effectiveness of an improved model to test dogs’ behavioral aptitude matching the expectations of a hypothetical adopter. The new version improves the test feasibility by the elimination of a previous computer-based program, and by the introduction of new items such as hierarchical behavior towards food. In this study dogs housed in the sanitary shelter of L’Aquila (Abruzzo, Italy), of different age and sex, either sterilized or not, and belonging to different breeds or crossbreeds, were tested. All the dogs adopted from the shelter were monitored for one year after the adoption by both phone interviews and home visit. The study aimed at analyzing if the shelter dogs showed a good and consistent behavior after adoption in the new environment. The results demonstrated that apart from a predictable relinquishment and an unfortunate case of abuse, none of the dogs adopted showed any unwanted behaviors such as house soiling, jumping up, separation-related and aggressive behaviors;this made their stay in the family a desirable, exciting experience independently of the dog sex, age, and the family composition. The authors stress the necessity of every shelter, together with the veterinary cares, for a professional expert at dogs’ behavior who can efficaciously prevent behavioral problems, eventually train the dogs and afford the pairing with humans in a competent, qualified manner. 展开更多
关键词 Adoption Behavioral test SHELTER DOGS training
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Rehabilitation training improves exercise tolerance after percutaneous coronary intervention 被引量:6
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作者 Fang Cui Yusheng Ren +1 位作者 Heng Jin Bo Cui 《The Journal of Biomedical Research》 CAS 2012年第4期248-252,共5页
The aim of this present study was to investigate the effects of training on exercise tolerance of patients with coronary heart disease after percutaneous coronary intervention.Fifty-seven cases of coronary heart disea... The aim of this present study was to investigate the effects of training on exercise tolerance of patients with coronary heart disease after percutaneous coronary intervention.Fifty-seven cases of coronary heart disease after percutaneous coronary intervention were divided randomly into the rehabilitation training group(26 cases) and control group(31 cases).Patients in the rehabilitation training group received rehabilitation training at different stages and exercise intensities 3 d after percutaneous coronary intervention for 3 months.The heart rate,blood pressure,ECG changes in treadmill exercise test,and the frequency of anginal episodes were observed.The results showed that NST and ΣST of ECG and the frequency of anginal episodes were significantly reduced in the rehabilitation training group.In addition,exercise tolerance was improved and the total exercise time was lengthened in these patients.Moreover,ST segment depression time and emergence time of angina with exercise were also lengthened compared with controls(P 〈 0.05,or 0.01).However,the heart rate and blood pressure before and after exercise of the two groups were similar.The study indicated that rehabilitation training could significantly relieve angina,amend ischemic features of ECG,and improve exercise tolerance of coronary heart disease patients after percutaneous coronary intervention. 展开更多
关键词 coronary heart disease percutaneous coronary intervention rehabilitation training exercise tolerance treadmill exercise test
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强化培训及模拟测试方法在住院医师规范化培训中的应用
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作者 韩敦正 曾文铤 +2 位作者 罗碧辉 潘秀娣 董旻昱 《中国继续医学教育》 2024年第11期98-102,共5页
目的研究考前强化培训及模拟测试方法在住院医师规范化培训(以下简称“住培”)过程中的应用效果,提高住培医师的培训质量与考核成绩。方法选取广州医科大学附属第一医院2020年11月及2021年12月参加水平测试的内科住培医师作为研究对象,... 目的研究考前强化培训及模拟测试方法在住院医师规范化培训(以下简称“住培”)过程中的应用效果,提高住培医师的培训质量与考核成绩。方法选取广州医科大学附属第一医院2020年11月及2021年12月参加水平测试的内科住培医师作为研究对象,于2021年起在“三大考”前进行强化培训,特别是对末位15%的学员进行个别辅导,并使用模拟考试(包括执业医师模拟考试及水平测试模拟考试)的方法以提高住培学员的最终考试成绩,随后比较2020年、2021年内科住培医师的业务水平测试(简称水平测试)考核结果及执业医师考试结果,分析强化培训与模拟考试的培训效果。结果通过考前强化培训,2021年的水平测试成绩较2020年有进步。2021年住培医师水平测试平均全国百分位为(73.90±23.29)%,高于2020年度的(55.23±28.52)%,差异有统计学意义(P<0.05);2021年住培医师水平测试平均全省百分位为(64.44±26.85)%,高于2020年度的(40.72±28.69)%,差异有统计学意义(P<0.001)。2020年度广州医科大学附属第一医院内科执业医师考试参加考试人数为20名,通过19名,通过率为95.00%;2021年度广州医科大学附属第一医院内科执业医师考试参加考试人数为24名,通过23名,通过率为95.83%。2020、2021年度的执业医师考试通过率比较,差异无统计学意义(P>0.05),连续2年均保持高通过率。2021年,第3、4、5次水平模拟考试成绩均高于第1、2次,差异有统计学意义(P<0.01)。结论通过考前多方面强化培训,及时发现问题并反馈住培医师模拟考试结果,根据模拟考试成绩因材施教,可显著提高整体的水平测试考核成绩;通过加强理论授课及过程管理,可以达到培养优秀临床医师、提高住培质量的目的。 展开更多
关键词 内科 住院医师 规范化培训 年度业务水平测试 培训质量 考核成绩
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以学科竞赛推动创新人才培养的《饲料分析与检测》教学改革 被引量:1
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作者 冯志华 郝艳霜 +1 位作者 芦春莲 陈宝江 《养殖与饲料》 2024年第5期133-137,共5页
[目的]为进一步提升《饲料分析与检测》课程中学生学习知识的积极性和实践能力,同时加强动物科学应用型人才的培养。[方法]将《饲料分析与检测》课堂教学与学科竞赛相结合,从饲料检测的必要性、学科竞赛的重要性以及饲料检测和学科竞赛... [目的]为进一步提升《饲料分析与检测》课程中学生学习知识的积极性和实践能力,同时加强动物科学应用型人才的培养。[方法]将《饲料分析与检测》课堂教学与学科竞赛相结合,从饲料检测的必要性、学科竞赛的重要性以及饲料检测和学科竞赛融合探索等方面进行探讨,对《饲料分析与检测》课程进行改革。[结果]通过在课程中增加竞赛项目,显著提升了学生的学习兴趣、实践操作和创新能力。[结论]以学科竞赛促进《饲料分析与检测》课堂教学的改革,有助于提高广大师生的积极性和实践能力并培养学生的创新能力,为社会推送创新型人才。 展开更多
关键词 饲料分析与检测 学科竞赛 创新人才培养 教学改革
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基于Teststand的列控车载系统自动测试方案的设计与实现 被引量:4
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作者 李自豪 徐先良 欧国恩 《铁道通信信号》 2021年第4期5-9,共5页
针对在既有人工测试环境中执行系统功能测试和集成测试时,测试用例多、测试周期长、人员需求量大,以及重复验证工作繁重等问题,设计并实现了一种基于Teststand的列控车载设备自动测试系统。该系统综合运用TestStand测试管理工具、AutoI... 针对在既有人工测试环境中执行系统功能测试和集成测试时,测试用例多、测试周期长、人员需求量大,以及重复验证工作繁重等问题,设计并实现了一种基于Teststand的列控车载设备自动测试系统。该系统综合运用TestStand测试管理工具、AutoIt自动化工具和Python开发技术,实现了自动化测试环境的搭建,经模拟测试人员的操作,完成了测试过程并自动生成测试报告,在保证测试覆盖率的前提下降低了人力和时间成本。 展开更多
关键词 列控系统 自动测试 测试管理工具 自动化工具 Python开发技术
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信创赋能、产教融合软件测试人才培养探索
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作者 王智钢 曾岳 《教育教学论坛》 2024年第43期181-184,共4页
信创,即信息技术应用创新。针对信息技术应用创新背景下软件测试的发展和创新,提出以新工科建设为指导,从价值引领赋能课程思政、人才需求赋能专业发展、技术工具赋能课程建设、应用项目赋能人才培养四个方面,借力信创测试,赋能软件测... 信创,即信息技术应用创新。针对信息技术应用创新背景下软件测试的发展和创新,提出以新工科建设为指导,从价值引领赋能课程思政、人才需求赋能专业发展、技术工具赋能课程建设、应用项目赋能人才培养四个方面,借力信创测试,赋能软件测试人才培养,通过产教协同软件测试人才供需对接融合、技术方法理论创新融合,以及成果资源优势互补融合三个方面,实现产教深度融合,以协同培养信创测试人才,使其参与信创测试项目,从事信创测试工作,服务信创测试生态,推动信息技术创新产业发展。 展开更多
关键词 新工科 信息技术应用创新 产教融合 软件测试 人才培养
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基于测试与训练系统的大学英语混合教学模式研究
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作者 张蔚东 赵冬梅 霍金侠 《河北能源职业技术学院学报》 2024年第2期93-96,共4页
数字化网络时代催生了众多英语测试与训练系统,基于某省属地方本科院校大学英语课程,利用U校园等测试与训练平台,探究大学英语混合教学模式建构,打造符合新时代社会和学生发展需求的线上线下混合式立体化课程体系。学生成绩测试和问卷... 数字化网络时代催生了众多英语测试与训练系统,基于某省属地方本科院校大学英语课程,利用U校园等测试与训练平台,探究大学英语混合教学模式建构,打造符合新时代社会和学生发展需求的线上线下混合式立体化课程体系。学生成绩测试和问卷调查以及访谈表明,基于测试与训练系统的大学英语混合教学能够优化教学模式,做到靶向定位、精准教学,提升大学英语教学效果。 展开更多
关键词 测试与训练系统 大学英语 混合教学模式
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动态空心圆柱扭剪试验的离散元模拟研究
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作者 崔新壮 包振昊 +2 位作者 郝建文 杜业峰 李向阳 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第10期3921-3932,共12页
为了揭示应力主轴旋转效应对土体宏细观动力特性的影响,提出土体动态空心圆柱扭剪试验的数值模拟方法,该方法采用FDM-DEM耦合技术模拟物理试验中的完全柔性边界条件,并基于动态伺服原理实现柔性约束下循环动剪应力的精确加载。以重载列... 为了揭示应力主轴旋转效应对土体宏细观动力特性的影响,提出土体动态空心圆柱扭剪试验的数值模拟方法,该方法采用FDM-DEM耦合技术模拟物理试验中的完全柔性边界条件,并基于动态伺服原理实现柔性约束下循环动剪应力的精确加载。以重载列车荷载为例,建立“心形”复杂应力路径下重载铁路路基土体动态空心圆柱扭剪的数值试验模型,并通过物理试验验证数值模拟方法的正确性,分析应力主轴旋转效应对土体颗粒的运动状态、局部孔隙率、平均配位数、组构等细观特性的影响。研究结果表明,重载列车荷载引起的应力主轴旋转效应加剧了表征土体细观结构各项参数的变化程度,并加快了重载铁路路基土体竖向塑性累积变形的发展。此研究实现了复杂应力路径下空心圆柱试样的动态加载数值模拟,可为阐明土体在复杂应力路径下的宏细观动力特性演化规律提供参考。 展开更多
关键词 离散元 动态空心圆柱扭剪试验 重载列车荷载 应力主轴旋转 重载铁路路基
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