Astronomical site selection work is very hard.Unmanned technologies are important trends and solutions.We present a relatively easy method to plan a high reliability site selection which can extend the time from site ...Astronomical site selection work is very hard.Unmanned technologies are important trends and solutions.We present a relatively easy method to plan a high reliability site selection which can extend the time from site deployment to returning for maintaining by unmanned confirming the site.First,we redefine the reliability of a site selection deployment with the parameter of the trusty time,which means when we must return,and which can be relatively easy for estimating.The redefinition makes the reliability parameter as a Bayesian probability,and can be obtained by estimating besides testing,which makes the evaluation of each device's reliability much easier.Then we use block diagram tools in the Matlab Simulink software to construct structure diagram,and to link each component with relations of parallel,serial,protection,and so on.This makes the whole reliability value can be calculated at the time when we design or plan a site selection.We applied this concept and method in an actual site selection in Lenghu,Qinghai Province,China.The survey practice reveals its effectiveness and simpleness.展开更多
The castings defects are affected by the melting volume change rate of material. The change rate has an important effect on running safety of the high temperature thermal storage chamber, too. But the characteristics ...The castings defects are affected by the melting volume change rate of material. The change rate has an important effect on running safety of the high temperature thermal storage chamber, too. But the characteristics of existing measuring installations are complex structure, troublesome operation and low precision. In order to measure the melting volume change rate of material accurately and conveniently, a self-designed measuring instrument, self-heating probe instrument, and measuring method are described. Temperature in heating cavity is controlled by PID temperature controller; melting volume change rate υ and molten density are calculated based on the melt volume which is measured by the instrument. Positive and negative υ represent expansion and shrinkage of the sample volume after melting, respectively. Taking eutectic LiF＋CaF2 for example, its melting volume change rate and melting density at 1 123 K are -20.6% and 2 651 kg/m–3 measured by this instrument, which is only 0.71% smaller than literature value. Density and melting volume change rate of industry pure aluminum at 973 K and analysis pure NaCl at 1 123 K are detected by the instrument too. The measure results are agreed with report values. Measuring error sources are analyzed and several improving measures are proposed. In theory, the measuring errors of the change rate and molten density which are measured by the self-designed instrument is nearly 1/20-1/50 of that measured by the refitted mandril thermal expansion instrument. The self-designed instrument and method have the advantages of simple structure, being easy to operate, extensive applicability for material, relatively high accuracy, and most importantly, temperature and sample vapor pressure have little effect on the measurement accuracy. The presented instrument and method solve the problems of complicated structure and procedures, and large measuring errors for the samples with high vapor pressure by existing installations.展开更多
This paper systematically summarizes previous measuring methods and observational instruments for the magnitude of dewfall on land surface, analyzes the characteristics of common observational instruments for land sur...This paper systematically summarizes previous measuring methods and observational instruments for the magnitude of dewfall on land surface, analyzes the characteristics of common observational instruments for land surface dewfall, and describes several basic dewfall measurement methods. Moreover, the basic principles of these methods and instruments are interpreted, and their advantages, disadvantages, and applicability are analyzed. Recommendations for the further improvement of these observational instruments and the development of dewfall measuring methods are presented, and new technologies and scientific proposals for exploiting dewfall are elucidated.展开更多
Economic modeling that yields practical value must cater for effects caused by exogenous variables. AutoRegressive eXogenous approach (ARX) has been widely used in regional economic studies. Instrumental Variable Meth...Economic modeling that yields practical value must cater for effects caused by exogenous variables. AutoRegressive eXogenous approach (ARX) has been widely used in regional economic studies. Instrumental Variable Method is regarded as a preferential method to parametric estimation in ARX modeling. However, traditional instrumental variable methods can only handle single variable which has limited its capability. This paper presents an extended instrumental variable method (EIVM) which is based on multiple variables. This provides the capability of taking into account of exogenous variables and reflects better the economic activities. A case study is conducted, which illustrates the application of the EIVM in modeling Northeastern economy in China.展开更多
With determination micro-Fe by 1, 10-phenanthroline spectrophotometry for example, they are systematically introduced the combinatorial measurement and regression analysis method application about metheodic principle,...With determination micro-Fe by 1, 10-phenanthroline spectrophotometry for example, they are systematically introduced the combinatorial measurement and regression analysis method application about metheodic principle, operation step and data processing in the instrumental analysis, including: calibration curve best linear equation is set up, measurand best linear equation is set up, and calculation of best value of a concentration. The results showed that mean of thrice determination , s = 0 μg/mL, RSD = 0. Results of preliminary application are simply introduced in the basic instrumental analysis for atomic absorption spectrophotometry, ion-selective electrodes, coulometry and polarographic analysis and are contrasted to results of normal measurements.展开更多
A new method of data access which can effectively resolve the problem of high speed and real time reading data of nuclear instrument in small storage space is introduced. This method applies the data storage mode of ...A new method of data access which can effectively resolve the problem of high speed and real time reading data of nuclear instrument in small storage space is introduced. This method applies the data storage mode of “linked list” to the system of Micro Control Unit (MCU), and realizes the pointer access of nuclear data on the small storage space of MCU. Experimental results show that this method can solve some problems of traditional data storage method, which has the advantages of simple program design, stable performance, accurate data, strong repeatability, saving storage space and so on.展开更多
The proposed design of a microwave superconducting kinetic inductance detector(MKID)array readout system characterizes the performance of MKIDs through a digital homodyne frequency mixing architecture.Meanwhile,the re...The proposed design of a microwave superconducting kinetic inductance detector(MKID)array readout system characterizes the performance of MKIDs through a digital homodyne frequency mixing architecture.Meanwhile,the readout system is implemented using a frequency division multiplexing circuit system,coupled with an FFT design to enable the readout of MKID arrays.The system is characterized by its compact size,low cost,portability,and ease of further development.Together,these features have significant implications for the design and readout of terahertz MKID arrays,while simultaneously advancing both the theoretical and practical aspects of MKID technology.展开更多
基金supported by the Investigation of Technological Infrastructure Resources(No.2023FY101101)the National Natural Science Foundation of China(NSFC)(No.11073027 and No.12373104)。
文摘Astronomical site selection work is very hard.Unmanned technologies are important trends and solutions.We present a relatively easy method to plan a high reliability site selection which can extend the time from site deployment to returning for maintaining by unmanned confirming the site.First,we redefine the reliability of a site selection deployment with the parameter of the trusty time,which means when we must return,and which can be relatively easy for estimating.The redefinition makes the reliability parameter as a Bayesian probability,and can be obtained by estimating besides testing,which makes the evaluation of each device's reliability much easier.Then we use block diagram tools in the Matlab Simulink software to construct structure diagram,and to link each component with relations of parallel,serial,protection,and so on.This makes the whole reliability value can be calculated at the time when we design or plan a site selection.We applied this concept and method in an actual site selection in Lenghu,Qinghai Province,China.The survey practice reveals its effectiveness and simpleness.
基金supported by Gansu Provincial Critical Patented Projects of China(Grant No. 1101ZSB117)Gansu Provincial Science and Technology Pillar Program of China(Grant No. 1002ZSB018)
文摘The castings defects are affected by the melting volume change rate of material. The change rate has an important effect on running safety of the high temperature thermal storage chamber, too. But the characteristics of existing measuring installations are complex structure, troublesome operation and low precision. In order to measure the melting volume change rate of material accurately and conveniently, a self-designed measuring instrument, self-heating probe instrument, and measuring method are described. Temperature in heating cavity is controlled by PID temperature controller; melting volume change rate υ and molten density are calculated based on the melt volume which is measured by the instrument. Positive and negative υ represent expansion and shrinkage of the sample volume after melting, respectively. Taking eutectic LiF＋CaF2 for example, its melting volume change rate and melting density at 1 123 K are -20.6% and 2 651 kg/m–3 measured by this instrument, which is only 0.71% smaller than literature value. Density and melting volume change rate of industry pure aluminum at 973 K and analysis pure NaCl at 1 123 K are detected by the instrument too. The measure results are agreed with report values. Measuring error sources are analyzed and several improving measures are proposed. In theory, the measuring errors of the change rate and molten density which are measured by the self-designed instrument is nearly 1/20-1/50 of that measured by the refitted mandril thermal expansion instrument. The self-designed instrument and method have the advantages of simple structure, being easy to operate, extensive applicability for material, relatively high accuracy, and most importantly, temperature and sample vapor pressure have little effect on the measurement accuracy. The presented instrument and method solve the problems of complicated structure and procedures, and large measuring errors for the samples with high vapor pressure by existing installations.
基金supported by the National Science Foundation of China (Grant Nos. 40830957 and 40575006)
文摘This paper systematically summarizes previous measuring methods and observational instruments for the magnitude of dewfall on land surface, analyzes the characteristics of common observational instruments for land surface dewfall, and describes several basic dewfall measurement methods. Moreover, the basic principles of these methods and instruments are interpreted, and their advantages, disadvantages, and applicability are analyzed. Recommendations for the further improvement of these observational instruments and the development of dewfall measuring methods are presented, and new technologies and scientific proposals for exploiting dewfall are elucidated.
文摘Economic modeling that yields practical value must cater for effects caused by exogenous variables. AutoRegressive eXogenous approach (ARX) has been widely used in regional economic studies. Instrumental Variable Method is regarded as a preferential method to parametric estimation in ARX modeling. However, traditional instrumental variable methods can only handle single variable which has limited its capability. This paper presents an extended instrumental variable method (EIVM) which is based on multiple variables. This provides the capability of taking into account of exogenous variables and reflects better the economic activities. A case study is conducted, which illustrates the application of the EIVM in modeling Northeastern economy in China.
文摘With determination micro-Fe by 1, 10-phenanthroline spectrophotometry for example, they are systematically introduced the combinatorial measurement and regression analysis method application about metheodic principle, operation step and data processing in the instrumental analysis, including: calibration curve best linear equation is set up, measurand best linear equation is set up, and calculation of best value of a concentration. The results showed that mean of thrice determination , s = 0 μg/mL, RSD = 0. Results of preliminary application are simply introduced in the basic instrumental analysis for atomic absorption spectrophotometry, ion-selective electrodes, coulometry and polarographic analysis and are contrasted to results of normal measurements.
文摘A new method of data access which can effectively resolve the problem of high speed and real time reading data of nuclear instrument in small storage space is introduced. This method applies the data storage mode of “linked list” to the system of Micro Control Unit (MCU), and realizes the pointer access of nuclear data on the small storage space of MCU. Experimental results show that this method can solve some problems of traditional data storage method, which has the advantages of simple program design, stable performance, accurate data, strong repeatability, saving storage space and so on.
基金funded by the National Key Research and Development Program of China under Nos.2023YFA1608200&2020YFC2201703the National Natural Science Foundation of China(NSFC,Grant No.12020101002)the Natural Science Foundation of China for the youth under No.12103093。
文摘The proposed design of a microwave superconducting kinetic inductance detector(MKID)array readout system characterizes the performance of MKIDs through a digital homodyne frequency mixing architecture.Meanwhile,the readout system is implemented using a frequency division multiplexing circuit system,coupled with an FFT design to enable the readout of MKID arrays.The system is characterized by its compact size,low cost,portability,and ease of further development.Together,these features have significant implications for the design and readout of terahertz MKID arrays,while simultaneously advancing both the theoretical and practical aspects of MKID technology.
