Gravity dam is a typical structure that has been frequently used in the fields of water conservancy engineering, and the safety of the structure has received widespread attention recently. Due to earthquakes or other ...Gravity dam is a typical structure that has been frequently used in the fields of water conservancy engineering, and the safety of the structure has received widespread attention recently. Due to earthquakes or other reasons, gravity dams normally have damage such as cracks in practical service. Damage in the structures can alter the structural dynamic behavior and seriously affect structural performance. Maintaining safety and integrity of the gravity dam structures requires a better understanding of dynamic response of structure with damage and associated damage detection method. In order to study thoroughly the dynamic behavior of gravity dam with damage, the sweep vibration responses of the gravity dam with and without damage are investigated. The experimental results show that the peak-peak acceleration responses all increase for the structure is with crack. At the same time, a structural damage detection method, i.e., the local damage factor (LDF) method, is considered in the study of gravity dam damage detection when the dam is subjected to the base excitation. It is shown that the LDF method can be used as a damage index and is capable of evaluating both the presence and relative severity of structural damage, and it can be used as a viable condition assessment and damage identification technique to detect and quantify the damage in the gravity dam.展开更多
We justify and extend the standard model of elementary particle physics by generalizing the theory of relativity and quantum mechanics. The usual assumption that space and time are continuous implies, indeed, that it ...We justify and extend the standard model of elementary particle physics by generalizing the theory of relativity and quantum mechanics. The usual assumption that space and time are continuous implies, indeed, that it should be possible to measure arbitrarily small intervals of space and time, but we ignore if that is true or not. It is thus more realistic to consider an extremely small “quantum of length” of yet unknown value <em>a</em>. It is only required to be a universal constant for all inertial frames, like<em> c</em> and <em>h</em>. This yields a logically consistent theory and accounts for elementary particles by means of four new quantum numbers. They define “particle states” in terms of modulations of wave functions at the smallest possible scale in space-time. The resulting classification of elementary particles accounts also for dark matter. Antiparticles are redefined, without needing negative energy states and recently observed “anomalies” can be explained.展开更多
A laboratory-made tumor cell detection device was fabricated based on both surface plasmon resonance imaging（SPRi） and image processing.In this device,a gravity-induced flow injection chip（gFIC） was exploited to r...A laboratory-made tumor cell detection device was fabricated based on both surface plasmon resonance imaging（SPRi） and image processing.In this device,a gravity-induced flow injection chip（gFIC） was exploited to replace a pump.Also two charge coupled devices（CCDs） were used to detect HepG2 cells by SPRi and image processing,respectively.The results of two CCDs are associated.Protein A was used to modify the sensing surface.The inlet angle was carefully adjusted for the device to get an enhanced image.In the test,the contrast among cell solutions at different concentrations can be easily distinguished.The other CCD using image processing can tell false-positive in some degree.This detection is label-free,real time,and precise.展开更多
基金supported by the National Basic Research Program of China ("973"Project)(Grant No. 2007CB714104)
文摘Gravity dam is a typical structure that has been frequently used in the fields of water conservancy engineering, and the safety of the structure has received widespread attention recently. Due to earthquakes or other reasons, gravity dams normally have damage such as cracks in practical service. Damage in the structures can alter the structural dynamic behavior and seriously affect structural performance. Maintaining safety and integrity of the gravity dam structures requires a better understanding of dynamic response of structure with damage and associated damage detection method. In order to study thoroughly the dynamic behavior of gravity dam with damage, the sweep vibration responses of the gravity dam with and without damage are investigated. The experimental results show that the peak-peak acceleration responses all increase for the structure is with crack. At the same time, a structural damage detection method, i.e., the local damage factor (LDF) method, is considered in the study of gravity dam damage detection when the dam is subjected to the base excitation. It is shown that the LDF method can be used as a damage index and is capable of evaluating both the presence and relative severity of structural damage, and it can be used as a viable condition assessment and damage identification technique to detect and quantify the damage in the gravity dam.
文摘We justify and extend the standard model of elementary particle physics by generalizing the theory of relativity and quantum mechanics. The usual assumption that space and time are continuous implies, indeed, that it should be possible to measure arbitrarily small intervals of space and time, but we ignore if that is true or not. It is thus more realistic to consider an extremely small “quantum of length” of yet unknown value <em>a</em>. It is only required to be a universal constant for all inertial frames, like<em> c</em> and <em>h</em>. This yields a logically consistent theory and accounts for elementary particles by means of four new quantum numbers. They define “particle states” in terms of modulations of wave functions at the smallest possible scale in space-time. The resulting classification of elementary particles accounts also for dark matter. Antiparticles are redefined, without needing negative energy states and recently observed “anomalies” can be explained.
基金Supported by the National Natural Science Foundation of China（Nos.31070772,31270907,21275129）.
文摘A laboratory-made tumor cell detection device was fabricated based on both surface plasmon resonance imaging（SPRi） and image processing.In this device,a gravity-induced flow injection chip（gFIC） was exploited to replace a pump.Also two charge coupled devices（CCDs） were used to detect HepG2 cells by SPRi and image processing,respectively.The results of two CCDs are associated.Protein A was used to modify the sensing surface.The inlet angle was carefully adjusted for the device to get an enhanced image.In the test,the contrast among cell solutions at different concentrations can be easily distinguished.The other CCD using image processing can tell false-positive in some degree.This detection is label-free,real time,and precise.
