Radon observation is an important measurement item of seismic precursor network observation.The radon detector calibration is a key technical link for ensuring radon observation accuracy.At present,the radon detector ...Radon observation is an important measurement item of seismic precursor network observation.The radon detector calibration is a key technical link for ensuring radon observation accuracy.At present,the radon detector calibration in seismic systems in China is faced with a series of bottleneck problems,such as aging and scrap,acquisition difficulties,high supervision costs,and transportation limitations of radon sources.As a result,a large number of radon detectors cannot be accurately calibrated regularly,seriously affecting the accuracy and reliability of radon observation data in China.To solve this problem,a new calibration method for radon detectors was established.The advantage of this method is that the dangerous radioactive substance,i.e.,the radon source,can be avoided,but only“standard instruments”and water samples with certain dissolved radon concentrations can be used to realize radon detector calibration.This method avoids the risk of radioactive leakage and solves the current widespread difficulties and bottleneck of radon detector calibration in seismic systems in China.The comparison experiment with the traditional calibration method shows that the error of the calibration coefficient obtained by the new method is less than 5%compared with that by the traditional method,which meets the requirements of seismic observation systems,confirming the reliability of the new method.This new method can completely replace the traditional calibration method of using a radon source in seismic systems.展开更多
The challenges of the ocean working environment and conditions require that marine instrumentsand equipment be highly reliable and environmentally adaptable.The various parts and componentsof marine instruments should...The challenges of the ocean working environment and conditions require that marine instrumentsand equipment be highly reliable and environmentally adaptable.The various parts and componentsof marine instruments should be interchangeable,so as to reduce product costs and reasonably economizethe use of energy and material resources.This paper intruduces the importance of formulating marine instrumentproduct standards,the present conditions and problems of marine product standards,and proposesrelated measures and suggestions to sovle the problems.展开更多
Stations are often regarded as change engines--places where passengers have to change as quickly and efficiently as possible from one mode of transport to another. Underpinned by research, NS （Netherlands Railways） ...Stations are often regarded as change engines--places where passengers have to change as quickly and efficiently as possible from one mode of transport to another. Underpinned by research, NS （Netherlands Railways） currently takes the view that stations should be transformed into dynamic urban portals that not only facilitate a speedy transfer but also make the stay at the station more enjoyable. To discover which aspects the customer perceives as important, NS developed a research method that is based on enviromnental psychology and with which the impact of passengers＇ waiting and station experience can be measured. This article addresses the measures taken, the method of measurement and the measurement results. Examples of such measures are： experimenting with colour, light, music, infotainment and increasing and repositioning the shopping facilities. Our studies not only showed an increase in the score for the general evaluation of a test station （Leiden Central Station） with one full point but also significant positive effects on various aspects of waiting and experience.展开更多
基金supported by the National Natural Science Foundation of China Study on the Key Technology of Non-radium Source Radon Chamber(No.42274235).
文摘Radon observation is an important measurement item of seismic precursor network observation.The radon detector calibration is a key technical link for ensuring radon observation accuracy.At present,the radon detector calibration in seismic systems in China is faced with a series of bottleneck problems,such as aging and scrap,acquisition difficulties,high supervision costs,and transportation limitations of radon sources.As a result,a large number of radon detectors cannot be accurately calibrated regularly,seriously affecting the accuracy and reliability of radon observation data in China.To solve this problem,a new calibration method for radon detectors was established.The advantage of this method is that the dangerous radioactive substance,i.e.,the radon source,can be avoided,but only“standard instruments”and water samples with certain dissolved radon concentrations can be used to realize radon detector calibration.This method avoids the risk of radioactive leakage and solves the current widespread difficulties and bottleneck of radon detector calibration in seismic systems in China.The comparison experiment with the traditional calibration method shows that the error of the calibration coefficient obtained by the new method is less than 5%compared with that by the traditional method,which meets the requirements of seismic observation systems,confirming the reliability of the new method.This new method can completely replace the traditional calibration method of using a radon source in seismic systems.
文摘The challenges of the ocean working environment and conditions require that marine instrumentsand equipment be highly reliable and environmentally adaptable.The various parts and componentsof marine instruments should be interchangeable,so as to reduce product costs and reasonably economizethe use of energy and material resources.This paper intruduces the importance of formulating marine instrumentproduct standards,the present conditions and problems of marine product standards,and proposesrelated measures and suggestions to sovle the problems.
文摘Stations are often regarded as change engines--places where passengers have to change as quickly and efficiently as possible from one mode of transport to another. Underpinned by research, NS （Netherlands Railways） currently takes the view that stations should be transformed into dynamic urban portals that not only facilitate a speedy transfer but also make the stay at the station more enjoyable. To discover which aspects the customer perceives as important, NS developed a research method that is based on enviromnental psychology and with which the impact of passengers＇ waiting and station experience can be measured. This article addresses the measures taken, the method of measurement and the measurement results. Examples of such measures are： experimenting with colour, light, music, infotainment and increasing and repositioning the shopping facilities. Our studies not only showed an increase in the score for the general evaluation of a test station （Leiden Central Station） with one full point but also significant positive effects on various aspects of waiting and experience.
