Technology of passive location has broad prospects in applications. In this paper, the method using the phase rate of change for the single observer passive location is introduced based on existing methods. One can ob...Technology of passive location has broad prospects in applications. In this paper, the method using the phase rate of change for the single observer passive location is introduced based on existing methods. One can obtain the direction of the target with phase information of two orthogonal interferometers on the observer and the radial distance with the corresponding phase rate of change. Then the target can be located with high speed and precision. A locating approach is given when the flying posture of t...展开更多
The Burris Gravity MeterTM manufactured by ZLS Corporation, Austin/Texas, USA, is based on the in- vention of L^R (L. LaCoste and A. Romberg): The ZLS (zero-length spring). A digital feedback system (range of ab...The Burris Gravity MeterTM manufactured by ZLS Corporation, Austin/Texas, USA, is based on the in- vention of L^R (L. LaCoste and A. Romberg): The ZLS (zero-length spring). A digital feedback system (range of about 50 mGal) is used to null the beam. Now, more than 120 gravity meters of this make exist worldwide and are used successfully in exploration, volcanology, geodetic work and surveying. The sensor is made of the well-known (L&R) metal-alloy zero-length spring providing a low drift characteristic. The drifts observed are comparable to L&R gravimeters and are less than 0.3 mGal per month, which is much lower than the drifts known for the fused quartz sensors. The dial is calibrated every 50 regal over the entire 7000 mGal meter range. Since the gravity value is determined at these points, there are no periodic errors. By a fourth heater circuit temperature effects are totally avoided. The gravity meter is controlled via Bluetoothce either to a handheld computer (tablet) or a notebook computer. The feedback responds with high stability and accuracy. The hulling of the beam is controlled by the UltraGravTM control system which incorporates an inherently linear PWM (pulse-width modulated) electrostatic feedback system. In order to improve the handling of the gravimeter we have developed two Windows based programs: AGESfield for single measurements and AGEScont for continuous readings.展开更多
Cells are the basic unit of human organs that are not fully understood.The revolutionary advancements of optical imaging alowed us to observe single cells in whole organs,revealing the complicated composition of cells...Cells are the basic unit of human organs that are not fully understood.The revolutionary advancements of optical imaging alowed us to observe single cells in whole organs,revealing the complicated composition of cells with spatial information.Therefore,in this review,we revisit the principles of optical contrast related to those biomolecules and the optical techniques that transform optical contrast into detectable optical signals.Then,we describe optical imaging to achieve threedimensional spatial discrimination for biological tisutes.Due to the milky appearance of tissues,the spatial information burred deep in the whole organ.Fortunately,strategies developed in the last decade could circumvent this issue and lead us into a new era of investigation of the cells with their original spatial information.展开更多
Technology of passive location has broad prospects inapplications. In this paper, the sin- gle observer passive locationmethod using phase rate of change is introduced based on existingmeth- ods. This new method can o...Technology of passive location has broad prospects inapplications. In this paper, the sin- gle observer passive locationmethod using phase rate of change is introduced based on existingmeth- ods. This new method can obtain the direction of he target withphase information of two orthogonal interferometers on the observerand the radial distance with the corresponding phase rate of change.Then the target can be located with high speed and precision. Somelocating expressions are given When the flying posture of theobserver is change. Simulations show that this method is effective.展开更多
The capability to image, as well as control and manipulate single molecules such as nucleic acids(DNA or RNA) can greatly enrich our knowledge of the roles of individual biomolecules in cellular processes and their be...The capability to image, as well as control and manipulate single molecules such as nucleic acids(DNA or RNA) can greatly enrich our knowledge of the roles of individual biomolecules in cellular processes and their behavior in native environments. Here we summarize the recent advances of single nucleic acid imaging based on optical observation and force manipulation. We start by discussing the superiority of single molecule image, the central roles nucleic acids play in biosystems, and the significance of single molecule image towards nucleic acids. We then list a series of representative examples in brief to illustrate how nucleic acid of various morphologies has been imaged from different aspects, and what can be learned from such characterizations. Finally,concluding remarks on parts of which should be improved and outlook are outlined.展开更多
文摘Technology of passive location has broad prospects in applications. In this paper, the method using the phase rate of change for the single observer passive location is introduced based on existing methods. One can obtain the direction of the target with phase information of two orthogonal interferometers on the observer and the radial distance with the corresponding phase rate of change. Then the target can be located with high speed and precision. A locating approach is given when the flying posture of t...
文摘The Burris Gravity MeterTM manufactured by ZLS Corporation, Austin/Texas, USA, is based on the in- vention of L^R (L. LaCoste and A. Romberg): The ZLS (zero-length spring). A digital feedback system (range of about 50 mGal) is used to null the beam. Now, more than 120 gravity meters of this make exist worldwide and are used successfully in exploration, volcanology, geodetic work and surveying. The sensor is made of the well-known (L&R) metal-alloy zero-length spring providing a low drift characteristic. The drifts observed are comparable to L&R gravimeters and are less than 0.3 mGal per month, which is much lower than the drifts known for the fused quartz sensors. The dial is calibrated every 50 regal over the entire 7000 mGal meter range. Since the gravity value is determined at these points, there are no periodic errors. By a fourth heater circuit temperature effects are totally avoided. The gravity meter is controlled via Bluetoothce either to a handheld computer (tablet) or a notebook computer. The feedback responds with high stability and accuracy. The hulling of the beam is controlled by the UltraGravTM control system which incorporates an inherently linear PWM (pulse-width modulated) electrostatic feedback system. In order to improve the handling of the gravimeter we have developed two Windows based programs: AGESfield for single measurements and AGEScont for continuous readings.
基金supported by the National Science and Technology Innovation 2030 Grant No. (2021ZD0200104)National Nature Science Foundation of China (81871082).
文摘Cells are the basic unit of human organs that are not fully understood.The revolutionary advancements of optical imaging alowed us to observe single cells in whole organs,revealing the complicated composition of cells with spatial information.Therefore,in this review,we revisit the principles of optical contrast related to those biomolecules and the optical techniques that transform optical contrast into detectable optical signals.Then,we describe optical imaging to achieve threedimensional spatial discrimination for biological tisutes.Due to the milky appearance of tissues,the spatial information burred deep in the whole organ.Fortunately,strategies developed in the last decade could circumvent this issue and lead us into a new era of investigation of the cells with their original spatial information.
文摘Technology of passive location has broad prospects inapplications. In this paper, the sin- gle observer passive locationmethod using phase rate of change is introduced based on existingmeth- ods. This new method can obtain the direction of he target withphase information of two orthogonal interferometers on the observerand the radial distance with the corresponding phase rate of change.Then the target can be located with high speed and precision. Somelocating expressions are given When the flying posture of theobserver is change. Simulations show that this method is effective.
基金supported by the National Natural Science Foundation of China (21525523, 21574048, 21375042, 21405054)the National Basic Research Program of China (2015CB932600, 2013CB933000)+1 种基金the Special Fund for Strategic New Industry Development of Shenzhen, China (JCYJ20150616144425376)1000 Young Talent (to Fan Xia)
文摘The capability to image, as well as control and manipulate single molecules such as nucleic acids(DNA or RNA) can greatly enrich our knowledge of the roles of individual biomolecules in cellular processes and their behavior in native environments. Here we summarize the recent advances of single nucleic acid imaging based on optical observation and force manipulation. We start by discussing the superiority of single molecule image, the central roles nucleic acids play in biosystems, and the significance of single molecule image towards nucleic acids. We then list a series of representative examples in brief to illustrate how nucleic acid of various morphologies has been imaged from different aspects, and what can be learned from such characterizations. Finally,concluding remarks on parts of which should be improved and outlook are outlined.