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汽车驾驶中车体感,车速感和车距感的训练
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作者 张中举 李存海 《汽车驾驶员》 1996年第8期16-17,共2页
关键词 汽车 驾驶 车体 车速 距感 训练 驾驶员
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挑战手机最小边框——艾迈斯半导体(ams)超窄边框光感距感解决方案
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作者 黄洲 《电子产品世界》 2019年第10期25-26,32,共3页
如今手机的屏幕越来越趋向于超大屏占比的无边框设计,而想要做到这一点实属不易。由于受话器与摄像模组的性能非常依赖于尺寸,所以挑战无边框的重任便落到了缩小光感与距感的占用面积之上。本文重点讨论了光感与距感模块设计的基本原理... 如今手机的屏幕越来越趋向于超大屏占比的无边框设计,而想要做到这一点实属不易。由于受话器与摄像模组的性能非常依赖于尺寸,所以挑战无边框的重任便落到了缩小光感与距感的占用面积之上。本文重点讨论了光感与距感模块设计的基本原理与技术要点,以及ams(艾迈斯半导体)的超窄边框光感距感解决方案的优势所在。 展开更多
关键词 超窄边框 距感
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Test and analysis of dynamic compaction vibration based on piezoelectric sensor
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作者 段伟 韩云山 +2 位作者 董彦莉 秦伟华 吴晗 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第2期116-122,共7页
The paper takes a new campus project site of Shanxi university town for example, tests the influence of dynamic com- paction vibration and vibration isolation effect of isolation trench on this ground, and compares th... The paper takes a new campus project site of Shanxi university town for example, tests the influence of dynamic com- paction vibration and vibration isolation effect of isolation trench on this ground, and compares the influences of the dynamic compaction vibration on surrounding buildings with isolation trench and without it. Furthermore, the attenuation law of dy- namic compaction vibration in fill foundation of the loess area under different tamping energy and how to determine safe distance of dynamic compaction construction are studied. And then the quantitative relationship between acceleration and vibration source in new campus project site is presented. We derive the evaluation method that dynamic compaction construction affects adjacent buildings by contrasting with the existing standards and norms. The monitoring results show that isolation trench makes the amplitude attenuation of the horizontal velocity of dynamic compaction vibration reach above 75%, and the safe dis- tance be 30 m under the tamping energy of 6 000 kN · m. Therefore, isolation trench is better for vibration reduction under dynamic compaction construction. 展开更多
关键词 dynamic compaction VIBRATION safety distance isolation trench piezoelectric sensor
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Distributed Localization Algorithm for Wireless Sensor Network Based on Multidimensional Scaling and the Shortest Path Distance Correction 被引量:2
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作者 丁英强 杜留锋 +1 位作者 杨挺 孙雨耕 《Transactions of Tianjin University》 EI CAS 2009年第4期237-244,共8页
Sensor localization is crucial for the configuration and applications of wireless sensor network (WSN). A novel distributed localization algorithm, MDS-DC was proposed for wireless sensor network based on multidimensi... Sensor localization is crucial for the configuration and applications of wireless sensor network (WSN). A novel distributed localization algorithm, MDS-DC was proposed for wireless sensor network based on multidimensional scaling (MDS) and the shortest path distance correction. In MDS-DC, several local positioning regions with reasonable distribution were firstly constructed by an adaptive search algorithm, which ensures the mergence between the local relative maps of the adjacent local position regions and can reduce the number of common nodes in the network. Then, based on the relationships between the estimated distances and actual distances of anchors, the distance estimation vectors of sensors around anchors were corrected in each local positioning region. During the computations of the local relative coordinates, an iterative process, which is the combination of classical MDS algorithm and SMACOF algorithm, was applied. Finally, the global relative positions or absolute positions of sensors were obtained through merging the relative maps of all local positioning regions. Simulation results show that MDS-DC has better performances in positioning precision, energy efficiency and robustness to range error, which can meet the requirements of applications for sensor localization in WSN. 展开更多
关键词 wireless sensor network (WSN) multidimensional scaling local positioning region relative coordinates
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Key technique of a detection sensor for coal mine wire ropes 被引量:3
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作者 WANG Hong-yao XU Zhao +4 位作者 HUA Gang TIAN Jie ZHOU Bing-bing LU Yan-hong CHEN Feng-jun 《Mining Science and Technology》 EI CAS 2009年第2期170-175,共6页
Wire ropes,employed extensively in coal mine hoists and transportation systems are subject to damage due to wear,corrosion and fatigue.The extent of damage and the carrying capacity of ropes are closely related to the... Wire ropes,employed extensively in coal mine hoists and transportation systems are subject to damage due to wear,corrosion and fatigue.The extent of damage and the carrying capacity of ropes are closely related to the sense of safety by staff and equipments.Magnetic flux leakage detection method(MFL),as an effective method,is these days widely used in detection of broken strands of wire ropes.In order to improve the accuracy of detection of flaws in wire ropes by magnetic flux leakage(MFL),the effect of the distance between a sensor and the surface of a wire rope(i.e.,lift-off) on detection by magnetic flux leakage was in-vestigated.An analysis of the main principles for the choice of lift-off is described by us and a new method that improves the structure of the detector is proposed from the point of view of the design of a magnetic circuit,to restrain the impact of fluctuations of sensor lift-off.The effect of this kind of method is validated by simulation and computation.The results show that the detection sensitivity is markedly increased by this method.Furthermore,the signal-to-noise ratio(SNR) can be increased by over 28%.This method will lend itself to offer reliable scientific information to optimize the structure of excitation devices and improve the accuracy of MFL detection. 展开更多
关键词 coal mine wire rope magnetic flux leakage detection LIFT-OFF
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Detection and Ranging System of Flight Aid Lights 被引量:1
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作者 YU Zhi-jing WANG Qiang 《Semiconductor Photonics and Technology》 CAS 2007年第1期20-24,共5页
Dynamic detection based on optics sensors and ranging radars is a new method to detect the luminous intensity of flight aid lights. The optics sensors can get the illumination information of each light, the ranging ra... Dynamic detection based on optics sensors and ranging radars is a new method to detect the luminous intensity of flight aid lights. The optics sensors can get the illumination information of each light, the ranging radar gets the distance information, and then data amalgamation technology is used to compute the luminous intensity of each light. A method to modify the errors of this dynamic detection system is presented. It avoids the accumulation error and measurement carrier’s excursion error by using peak value detection based on optics sensors to estimate the accurate position of each light, then to modify the lights’ lengthways distance information and transverse position information. The performance of the detection and ranging system is validated by some experiments and shown in pictures. 展开更多
关键词 luminous intensity dynamic detection ILLUMINATION optics sensor
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Normative Versus Perceptual Gap Analysis of Hotel Product Quality as a Service to Tourism in Kenya
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作者 Joe Kibuye Wadawi Frederick Jacobus Herbst Nerine Cecilia Bresler 《Chinese Business Review》 2011年第12期1091-1105,共15页
Kenya's tourism business stagnated from 1991 to 2003 and only registered small but steady grew from 2004. One of the sectors that recorded poor performance as a result of the slow growth of tourism is the hotel busin... Kenya's tourism business stagnated from 1991 to 2003 and only registered small but steady grew from 2004. One of the sectors that recorded poor performance as a result of the slow growth of tourism is the hotel business. Despite this slack, stakeholders in Kenya have not tried to assess the extent to which the quality of this sector may impact on destination preference. The ultimate purpose of this research was to establish the quality gap between the expected and the perceived hotel product/service quality from both the perspective of the tourists and the hotel operators in Kenya. It was motivated by the need to create parameters that can elavate the competitiveness of Kenya's tourism using the hotel product/service quality offer. Descriptive quantitative research design was used to establish the secondary objectives and to assess two propositions set for the study. A sample of 211 tourists and 19 hotel operators in two major tourist provinces of Kenya was used to obtain information regarding normative and perceptive hotel product/service quality. Kenya's only destination marketing organisation, Kenya Tourist Board (KTB) marketers were also surveyed to provide insight on Kenya's destination position with regard to the motivation of tourists to visit Kenya. The study established that although the attractions which make tourists come to Kenya are the unique wildlife safari, beach tourism and the natural scenery, hotel product quality and hospitality plays a vital role in motivating tourists to choose Kenya as the destination to visit. However, this study found out that while the tourists and hotel operators agree on the normative hotel product quality level, there is a significant gap between the normative quality and the perceptual quality registered by tourists who used hotel services. The study established that hotel operators only recognize quality regulatory institutions with statutory and legal authority to incriminate facilities that do not comply with laid down operational requirements such as Hotels and Restaurants Authority and the Local Authority Public Health Department. The study has proposed an integrated framework that may be utilized to build a superior national hotel product/service quality so that the economic potential of tourism is maximized in Kenya. 展开更多
关键词 destination marketing TOURISM COMPETITIVENESS Kenya tourism hotel product/service quality
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Middle range wireless power transfer systems with multiple resonators 被引量:1
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作者 陈新 张桂香 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第6期2127-2136,共10页
The equivalent two-port network model of a middle range wireless power transfer(WPT) system was presented based on strongly coupled multiple resonators. The key parameters of the WPT system include self-inductance, re... The equivalent two-port network model of a middle range wireless power transfer(WPT) system was presented based on strongly coupled multiple resonators. The key parameters of the WPT system include self-inductance, resistance, parasitic capacitance, mutual inductance and S-parameters of coils & resonators were analyzed. The impedance matching method was used to optimize load power and transmission efficiency of the multi-resonator WPT system, and the impedance matching method was realized through adjusting the distances between the coils and resonators. Experiments show that the impedance matching method can effectively improve load power and transmission efficiency for middle range wireless power transfer systems with multiple resonators, at distances up to 3 times the coil radius with efficiency more than 70% and load power also close to 3.5 W. 展开更多
关键词 wireless power transfer middle range multiple resonators S-PARAMETERS two-port network impedance matching
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Compare Quantum Operation Sensitivity for Different Distance Measures
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作者 麻志浩 王渺寅 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第4期635-636,共2页
In this paper, we compare the quantum operation sensitivity for different distance measures. We find that, among all usual distance measures, Bures fidelity is more sensitive to quantum operation than others. This may... In this paper, we compare the quantum operation sensitivity for different distance measures. We find that, among all usual distance measures, Bures fidelity is more sensitive to quantum operation than others. This may explain in some sense why fidelity is so useful in quantum information theory. 展开更多
关键词 FIDELITY quantum operation
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A Survey of Ranging Algorithms and Localization Schemes in Underwater Acoustic Sensor Network 被引量:4
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作者 QU Fengzhong WANG Shiyuan +1 位作者 WU Zhihui LIU Zubin 《China Communications》 SCIE CSCD 2016年第3期66-81,共16页
Underwater Acoustic Sensor Network(UASN) has attracted significant attention because of its great influence on ocean exploration and monitoring. On account of the unique characteristics of underwater environment, loca... Underwater Acoustic Sensor Network(UASN) has attracted significant attention because of its great influence on ocean exploration and monitoring. On account of the unique characteristics of underwater environment, localization, as one of the fundamental tasks in UASNs, is a more challenging work than in terrestrial sensor networks. A survey of the ranging algorithms and the network architectures varied with different applications in UASNs is provided in this paper. Algorithms used to estimate the coordinates of the UASNs nodes are classified into two categories: rangebased and range-free. In addition, we analyze the architectures of UASNs based on different applications, and compare their performances from the aspects of communication cost, accuracy, coverage and so on. Open research issues which would affect the accuracy of localization are also discussed, including MAC protocols, sound speed and time synchronization. 展开更多
关键词 underwater acoustic communication underwater acoustic sensor network localization
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Technical Analyses of the Interference Effect of “Advanced Radar”
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作者 张锡祥 张忠捷 《Journal of Measurement Science and Instrumentation》 CAS 2010年第1期71-73,共3页
The conception of "advanced radar" is introduced and lint forward, while it is proved that the weakpoints of interference can still be employed. Meanwhile, the paper expounds the principle how Over-The-Horizon Radar... The conception of "advanced radar" is introduced and lint forward, while it is proved that the weakpoints of interference can still be employed. Meanwhile, the paper expounds the principle how Over-The-Horizon Radar(OTHR) works, and derives the OTHR interference equation. By listing the OTHR examples, it analyzes and calculates the equivalent power of the OTHR and the sensitivity of the receiver to build up a block diagram how the interferencer is structured. Hence, the effective area is achieved, and OTHR can be intereferenced effectively with not so high equivalent power. 展开更多
关键词 OTHR INTERFERENCE advanced radar
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Relationship between the sensor temperature and moxibustion distance of mild moxibustion 被引量:2
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作者 戴国斌 刘琼 +7 位作者 孙天爱 刘迈兰 梁昊 丁家峰 许雪梅 刘密 吴焕淦 常小荣 《World Journal of Acupuncture-Moxibustion》 CSCD 2017年第4期13-19,共7页
Objective To explore the relationship between the receptor temperature and moxibustion distance of mild moxibustion, and provide evidence for clinical moxibustion distance. Methods Mild moxibustion was carried out for... Objective To explore the relationship between the receptor temperature and moxibustion distance of mild moxibustion, and provide evidence for clinical moxibustion distance. Methods Mild moxibustion was carried out for 15min by adopting moxibustion shelf, and the moxibustion ash was shook off automatically for once every 3 min. The distance between moxa stick and temperature sensor was set as 2 cm, 3 cm, 4 cm and 5 cm, respectively, by ruler. The temperature was recorded for once every 2 s with photothermal detection system for moxibustion combustion to form a temperature profile. The initial temperature, maximum temperature and average temperature were observed, and the experimental data were analyzed via SPSS18.0 statistical software. Results The initial receptor temperature was (25.33±0.29) ℃ when the moxibustion distance was 2 cm, (25.29±0.05) ℃ when the moxibustion distance was 3 cm, (25.43±0.17) ℃ when the moxibustion distance was 4cm, and (25.16±0.22) ℃ when the moxibustion distance was 5 cm, respectively. The maximum temperature was (74.96±1.20) ℃ when the moxibustion distance was 2 cm, (51.70±0.74) ℃ when the moxibustion distance was 3 cm, (49.33±0.40) ℃ when the moxibustion distance was 4 cm, and (42.50±0.26) ℃ when the moxibustion distance was 5 cm, respectively. The average temperature was (62.40±7.84) ℃-(62.68±7.58) ℃ when the moxibustion distance was 2 cm, (44.77±3.31) ℃-(45.11±3.21) ℃ when the moxibustion distance was 3 cm, (42.72+3.86) ℃-(43.12±3.54) ℃ when the moxibust-ion distance was 4 cm, and (38.45±1.67) ℃-(38.50±1.63) ℃ when the moxibustion distance was 5 cm, respectively. The temperature curve showed that the fluctuation range was the maximum when the moxibustion distance was 2 cm, larger when the moxibustion distance was 3 cm, smaller when the moxibustion distance was 4 cm, and minimum when the moxibustion distance was 5 cmo There was no significant difference in the initial temperature of mild moxibustion at different distances, however, the maximum temperature, average temperature and the fluctuation range of temperature curve were closely related to the moxibustion distance. Conclusion The nearer the distance is, the higher the maximum temperature and average temperature as well as the larger the fluctuation range will be, and the farther the distance is, the lower the maximum temperature and average temperature as well as the smaller the fluctuation range will be. Accordin8 to preliminary analysis, the temperature will be the most suitable when the moxibust-ion distance is 3 cm-4 cm. 展开更多
关键词 Mild moxibustion DISTANCE receptor temperature temperature sensor photothermal detection system for moxibustion combustion
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Investigation of loading and force sensing properties of a probe-type microforce sensor with force-distance curves 被引量:3
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作者 SUN Chen SU DongChuan LI XiDe 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第6期1362-1370,共9页
In this paper,the force-distance curves have been employed to investigate the force sensing properties of the probe-type microforce sensors.In the preliminary studies,two kinds of probe-type microforce sensors have be... In this paper,the force-distance curves have been employed to investigate the force sensing properties of the probe-type microforce sensors.In the preliminary studies,two kinds of probe-type microforce sensors have been used to load the objects with dry and wetted surfaces.One is a developed piezoresistive cantilever force sensor with sensitivity of 35 μN/V and the other an atomic force microscope(AFM) cantilever beam probe with sensitivity of 10.4 nN/V.The force outputs corresponding to the regimes of approaching,indenting,and loading are obtained,and the properties of the stability in the approaching regime of the sensors,local mechanical behavior of the tested objects in the indenting regime,and the force sensing of the global samples are analyzed.Experimental results of this analysis are also presented. 展开更多
关键词 force sensor PROBE force-distance curve mechanical behavior surface effects
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Blade Tip Timing Vibration Monitoring Method Based on Fiber Bragg Grating 被引量:1
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作者 Fei WU Lei LIANG Junya XING Lin WANG Lang JIA 《Photonic Sensors》 SCIE EI CAS 2014年第2期188-192,共5页
The ventilators have been vividly called "the lungs of mine". The rotating blades are the core parts of a ventilator, they can influence the safety and reliability of the ventilator. This paper will use the tip-timi... The ventilators have been vividly called "the lungs of mine". The rotating blades are the core parts of a ventilator, they can influence the safety and reliability of the ventilator. This paper will use the tip-timing method based on the fiber Bragg grating magnetically coupling sensor to study and analyze the ventilator blade vibration, in order to realize long-distance and non-contact real-time online safety monitoring of blade vibration. Compared with the electronic sensorand fiber intensity reflective sensor, the fiber grating coupling magnetic sensor has such advantages as explosion-proof, working at harsh environment with humid air, dust and greasy dirt, capable of achieving long-distance signal transmission, and joining easily with other fiber Bragg grating sensors to form a network in order to achieve multi-parameter distributed online monitoring. 展开更多
关键词 Blade vibration fiber Bragg grating magnetic coupling SENSOR
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The Thermal Character of the Underwater Heat Exhausting Source 被引量:2
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作者 Shengtao Chen,Huanying Liu and Yi Qi Science and Technology on Underwater Test and Control Laboratory,PO Box 67,Dalian,Liaoning 116013 《Journal of Thermal Science》 SCIE EI CAS CSCD 2010年第5期445-450,共6页
The underwater heat exhausting source can cause the thermal difference of the surrounding and surface water.In this paper,the thermal character caused by the underwater heat exhausting source is studied by numerical s... The underwater heat exhausting source can cause the thermal difference of the surrounding and surface water.In this paper,the thermal character caused by the underwater heat exhausting source is studied by numerical simulation and experiment.The results show that the thermal floating distance is related with the sailing velocity of the underwater target.The higher the velocity is,the longer the hot wake is,and the broader the hot scope is.The relative distance of the thermal floating spot is almost in a logarithmic law with the velocity.The experimental results are accordant with the numerical simulation,and the obvious hot wake can be observed by the moving underwater heat exhausting source testing with temperature sensors and infrared camera. 展开更多
关键词 heat exhausting hot wake thermal character underwater target
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