Taking the mechanism of technological construction guidance theory and mode which consists of "objective-construction-evaluation-construction-objective" as a starting point, on the basis of county agricultur...Taking the mechanism of technological construction guidance theory and mode which consists of "objective-construction-evaluation-construction-objective" as a starting point, on the basis of county agricultural technological innovation ability and its index definition, this paper researches the constructing system of county agricultural technological innovation ability. Firstly, on the basis of defining county agricultural technological innovation ability and the definition of index, according to the principle of purposefulness, scientificity, systematicness, integration of dynamic state and static state, integration of quantitativeness and qualitativeness and so on, we construct the multi-level measuring system of county agricultural technological innovation ability, including 4 first-level indices, namely technological innovation environment, technological innovation basis, technological innovation ability, and technological innovation efficiency; 15 second-level indices, such as technological policy, technological system mechanism, technological institution construction, ability of innovation subject, ability of industrial expansion, scale merit, technological contribution rate. Moreover, this system has 45 third-level indices. Then, by using unascertained mathematics method and AHM method, we establish the multi-level unascertained composite measuring model of county agricultural technological innovation ability index. Finally, by using the survey data of one county in Hebei Province, and the established county agricultural technological innovation ability index model, we get the county agricultural technological innovation ability index of 0.711 by calculation, that is, the innovation ability is at the intermediate level, namely the modern agricultural sub-stage. The empirical research proves the correctness and applicability of this model.展开更多
In order to detect the refractive index of liquid with high precision,based on modular interference,Mach-Zehnder optical fiber refractive rate sensor was studied.Sensor structure is composed of ordinary single-mode fi...In order to detect the refractive index of liquid with high precision,based on modular interference,Mach-Zehnder optical fiber refractive rate sensor was studied.Sensor structure is composed of ordinary single-mode fiber and multimode fiber,according to the singlemode multimode singlemode sequence to fuse together,and the fused optical fiber is used to process the taper.As a result,the diameter of the sensing head is about 10μm.Experimental results show that,as liquid refractive index increases range from 1.33 to 1.35,the loss peak of the transmission spectrum will shift to long wave direction.展开更多
We proposed and experimentally demonstrated a cascaded tilted fiber Bragg grating(TFBG)for enhanced refractive index sensing.The TFBG is UV-inscribed in series in ordinary single-mode fiber(SMF)and reduced-diameter SM...We proposed and experimentally demonstrated a cascaded tilted fiber Bragg grating(TFBG)for enhanced refractive index sensing.The TFBG is UV-inscribed in series in ordinary single-mode fiber(SMF)and reduced-diameter SMF with the same tilt angle,and then excites two sets of superposed spectral combs of cladding modes.The cascaded TFBG with total length of 18 mm has a much wider wavelength range over 100 nm and narrower wavelength separation than that of a TFBG only in the SMF,enabling an enlarged range and a higher accuracy of refractive index measurement.The fabricated TFBG with the merits of enhanced sensing capability and temperature self-calibration presents great potentials in the biochemical sensing applications.展开更多
Wavelength 1064 nm is one of the most widely used laser wavelengths in industries and science. The high-precision measurement of the refractive index of optical materials at 1064 nm is significant for improving the op...Wavelength 1064 nm is one of the most widely used laser wavelengths in industries and science. The high-precision measurement of the refractive index of optical materials at 1064 nm is significant for improving the optical design. We study the direct measurement of refractive index at 1064nm of lasers, including cMcium fluoride (CaF2), fused silica and zinc selenide (ZnSe), whose refractive indices cover a large range from 1.42847 to 2.48272. The measurement system is built based on the quasi-common-path Nd:YAG laser feedback interferometry. The thickness can be measured simultaneously with the refractive index. The results demonstrate that the system has absolute uncertainties of ~10-5 and ~10-4 mm in refractive index and thickness measurement, respectively.展开更多
We present the thermal expansion coefficient (TEC) measurement technology of compensating for the effect of variations in the refractive index based on a Nd: YA G laser feedback system, the beam frequency is shifte...We present the thermal expansion coefficient (TEC) measurement technology of compensating for the effect of variations in the refractive index based on a Nd: YA G laser feedback system, the beam frequency is shifted by a pair of aeousto-optic modulators and then the heterodyne phase measurement technique is used. The sample measured is placed in a muffle furnace with two coaxial holes opened on the opposite furnace walls. The measurement beams hit perpendicularly and coaxially on each surface of the sample. The reference beams hit on the reference mirror and the high-refiectivity mirror, respectively. By the heterodyne configuration and computing, the influences of the vibration, distortion of the sample supporter and the effect of variations in the refractive index are measured and largely minimized. For validation, the TECs of aluminum samples are determined in the temperature range of 29-748K, confirming not only the precision within 5 × 10-7 K-1 and the accuracy within 0.4% from 298K to 448K but also the high sensitivity non-contact measurement of the lower reflectivity surface induced by the sample oxidization from 448 K to 748 K.展开更多
A refractive index (RI) sensor based on hybrid long-period fiber grating (LPFG) with multimode fiber core (MMFC) is proposed and demonstrated. The surrounding RI can be determined by monitoring the separation be...A refractive index (RI) sensor based on hybrid long-period fiber grating (LPFG) with multimode fiber core (MMFC) is proposed and demonstrated. The surrounding RI can be determined by monitoring the separation between the resonant wavelengths of the LPFG and MMFC since the resonant wavelengths of the LPFG and MMFC will shift in opposite directions when the surrounding RI changes. Experimental results show that the sensor possesses an enhanced sensitivity of 526.92nm/RIU in the RI range of 1.387-1.394 RIU. The response to the temperature is also discussed.展开更多
In this paper,a new concept of forward-pumped random Raman fiber laser(RRFL)-based liquid refractive index sensing is proposed for the first time.For liquid refractive index sensing,the flat fiber end immersed in the ...In this paper,a new concept of forward-pumped random Raman fiber laser(RRFL)-based liquid refractive index sensing is proposed for the first time.For liquid refractive index sensing,the flat fiber end immersed in the liquid can act as the point reflector for generating random fiber lasing and also as the sensing head.Due to the high sensitivity of the output power of the RRFL to the reflectivity provided by the point reflector in the ultralow reflectivity regime,the proposed RRFL is capable of achieving liquid refractive index sensing by measuring the random lasing output power.We theoretically investigate the effects of the operating pump power and fiber length on the refractive index sensitivity for the proposed RRFL.As a proof-of-concept demonstration,we experimentally realize high-sensitivity half-open short-cavity RRFL-based liquid refractive index sensing with the maximum sensitivity and the sensing resolution of-39.88W/RIU and 2.5075×10^(-5) RIU,respectively.We also experimentally verify that the refractive index sensitivity can be enhanced with the shorter fiber length of the RRFL.This work extends the application of the random fiber laser as a new platform for highly-sensitive refractive index sensing in chemical,biomedical,and environmental monitoring applications,etc.展开更多
Three-dimensional(3D)refractive index(RI)distribution is important to reveal the object’s inner structure.We implemented terahertz(THz)diffraction tomography with a continuous-wave single-frequency THz source for mea...Three-dimensional(3D)refractive index(RI)distribution is important to reveal the object’s inner structure.We implemented terahertz(THz)diffraction tomography with a continuous-wave single-frequency THz source for measuring 3D RI maps.The off-axis holographic interference configuration was employed to obtain the quantitative scattered field of the object under each rotation angle.The 3D reconstruction algorithm adopted the filtered backpropagation method,which can theoretically calculate the exact scattering potential from the measured scattered field.Based on the Rytov approximation,the 3D RI distribution of polystyrene foam spheres was achieved with high fidelity,which verified the feasibility of the proposed method.展开更多
[Objectives]In order to better understand the performance of Kongshan cattle,their growth and development was analyzed.[Methods]The body weights of 106 kongshan cattle at different month ages were measured,and the gro...[Objectives]In order to better understand the performance of Kongshan cattle,their growth and development was analyzed.[Methods]The body weights of 106 kongshan cattle at different month ages were measured,and the growth curves and body measurement indices of Kongshan cattle after one year old were analyzed by SPPS18.0.[Results]Kongshan cattle have good body shape.Compared with 1985,the performance of body measurements and weight was improved significantly;and the body measurements and body weight of Kongshan cattle increased significantly after 24 months old,indicating that Kongshan cattle still have good fattening performance in adulthood.[Conclusions]This study analyzed the growth and development laws of Kongshan cattle and the status quo of the population,and will provide some help for the selection and utilization of Kongshan cattle breed more intuitively.展开更多
Self-excited oscillation in a collapsible tube is an important phenomenon in physiology. An experimental approach on self-excited oscillation in a thin-walled collapsi- ble tube is developed by using a high transmitta...Self-excited oscillation in a collapsible tube is an important phenomenon in physiology. An experimental approach on self-excited oscillation in a thin-walled collapsi- ble tube is developed by using a high transmittance and low Young's modulus silicone rubber tube. The elastic tube is manufactured by the method of centrifugal casting in our laboratory. An optical method for recording the evolution of the cross-sectional areas at a certain position along the longitudinal direction of the tube is developed based on the technology of refractive index matching. With the transparent tube, the tube law is measured under the static no-flow condition. The cross section at the middle position of the tube transfers from a quasi-circular configuration to an ellipse, and then to a dumbell-shape as the chamber pressure is increased. During the self-excited oscillation, two periodic self-excited oscillating states and one transitional oscillating state are identified. They all belong to the LU mode. These different oscillating states are related to the initial cross-sectional shape of the tube caused by the difference of the downstream transmural pressure.展开更多
Vulnerability technology is the basic of network security technology,vulnerability quantitative grading methods,such as CVSS,WIVSS,ICVSS,provide a reference to vulnerability management,but the problems of ignoring the...Vulnerability technology is the basic of network security technology,vulnerability quantitative grading methods,such as CVSS,WIVSS,ICVSS,provide a reference to vulnerability management,but the problems of ignoring the risk elevation caused by a group of vulnerabilities and low accuracy of exploitable level evaluation exist in current vulnerability quantitative grading methods.To solve problems above in current network security quantitative evaluation methods,this paper verified the high relevance degree between type and exploitable score of vulnerability,proposed a new vulnerability quantitative grading method ICVSS,ICVSS can explore attack path using continuity level defined by privilege,add vulnerability type to measure indexes of exploitable metrics and use Analytic Hierarchy Process(AHP)to quantify the influence of vulnerability type on exploitable level.Compared with CVSS and WIVSS,ICVSS is proved that it can discover attack path consist of a sequence of vulnerabilities for network security situation evaluation,and has more accuracy and stability.展开更多
[ Objective] To study the meat production performance of geese in different crossbred combination, and provide a reference for cultivating new multiplication strains of meat geese. [Method] A total of five goose breed...[ Objective] To study the meat production performance of geese in different crossbred combination, and provide a reference for cultivating new multiplication strains of meat geese. [Method] A total of five goose breeds including Taihu goose (T), Wulong goose (WL), Wanxi white goose (WX), Sichuan white goose (SC) and Sanhua goose (SH) were used as research objects, and eight crossbred combinations were designed. The body measurements, slaughter performance, conventional meat quality and muscle composition of 90-day-old geese in eight crossbred combinations were determined and comparatively analyzed. [ Result] All the body measurement indexes except thud width of WXSC combination were the biggest in the eight crossbred combinations. Contrarily, the body measurement indexes of SHSC combination, including average body weight, body slope length, breast depth, breast width, shank length, neck length and half-diving depth were the lowest in the eight crossbred combinations. The live weight, slaughter weight and abdomen fat weight of WXSC combinations ware 3 291.36, 2 956.46 and 77.84 g, respectively, which were the biggest in eight crossbred combinations. The slaughter rate of SHWL combinations was 92.96%, and more than other crossbred combinations. The shear force of SHT and WXWL combinations were the lowest (3.09 kg) and the highest (3.78 kg), respectively. The water holding capacities of SCWL and WXSC combinations were the highest (66.46%) and the lowest (61.48%), respectively. The percentage of moisture content of SHWL and SCT combinations were the highest (73.05%) and the lowest (66.77%), respectively. The crude protein content of SHT and SHWL combinations were the highest (23.32%) and the lowest (21.94%), respectively. The percentage of crude fat content of SHT and SCWL combinations were the highest (3.06%) and the lowest (1.67%), respectively. [ Concusion] The growth rate of WXSC combination is the fastest, and the meat performance of SHT combination is the best.展开更多
Advanced technology used for arithmetic computing application,comprises greater number of approximatemultipliers and approximate adders.Truncation and Rounding-based Scalable ApproximateMultiplier(TRSAM)distinguish a ...Advanced technology used for arithmetic computing application,comprises greater number of approximatemultipliers and approximate adders.Truncation and Rounding-based Scalable ApproximateMultiplier(TRSAM)distinguish a variety of modes based on height(h)and truncation(t)as TRSAM(h,t)in the architecture.This TRSAM operation produces higher absolute error in Least Significant Bit(LSB)data shift unit.A new scalable approximate multiplier approach that uses truncation and rounding TRSAM(3,7)is proposed to increase themultiplier accuracy.With the help of foremost one bit architecture,the proposed scalable approximate multiplier approach reduces the partial products.The proposed approximate TRSAM multiplier architecture gives better results in terms of area,delay,and power.The accuracy of 95.2%and the energy utilization of 24.6 nJ is observed in the proposed multiplier design.The proposed approach shows 0.11%,0.23%,and 0.24%less Mean Absolute Relative Error(MARE)when compared with the existing approach for the input of 8-bit,16-bit,and 32-bit respectively.It also shows 0.13%,0.19%,and 0.2%less Variance of Absolute Relative Error(VARE)when compared with the existing approach for the input of 8-bit,16-bit,and 32-bit respectively.The proposed approach is implemented with Field-Programmable Gate Array(FPGA)and shows the delay of 3.640,6.481,12.505,22.572,and 36.893 ns for the input of 8-bit,16-bit,32-bit,64-bit,and 128-bit respectively.The proposed approach is applied in digital filters designwhich shows the Peak-Signal-to-NoiseRatio(PSNR)of 25.05 dB and Structural Similarity Index Measure(SSIM)of 0.98 with 393 pJ energy consumptions when used in image application.The proposed approach is simulated with Xilinx and MATLAB and implemented with FPGA.展开更多
The collaboration tools offered by Cloud Computing have increased the need to share data and services within companies or between autonomous organizations. This has led to the deployment of community cloud infrastruct...The collaboration tools offered by Cloud Computing have increased the need to share data and services within companies or between autonomous organizations. This has led to the deployment of community cloud infrastructures. However, several challenges will arise from this grouping of heterogeneous organizations. One of the main challenges is the management of trust between the actors of the community. Trust issues arise from the uncertainty about the quality of the resources and entities involved. The quality of a resource can be examined from a security or functional perspective. Therefore, ensuring security and monitoring the quality of resources is to ensure a high level of trust. Therefore, we propose in this paper a technique for dynamic trust management and quality monitoring of resources shared between organizations. Our approach consists, on the one hand, in evaluating the quality of resources based on quality of service measurement attributes and, on the other hand, in updating the trust values according to the information deduced from these measurements. The proposed framework is evaluated in terms of resource sharing success rate and execution time. Experimental results and comparison with TNA-SL and InterTrust models show that the framework can identify and track the behavior of malicious organizations with relatively low execution time.展开更多
Knowledge has become the most important strategic resource of firms, and the competition among firms is more based on knowledge than before. To deal with this challenge, some firms are trying to develop knowledge stra...Knowledge has become the most important strategic resource of firms, and the competition among firms is more based on knowledge than before. To deal with this challenge, some firms are trying to develop knowledge strategies to direct their knowledge management activities, but current strategic performance measurement systems can't evaluate the performance of knowledge strategies appropriately. This article develops a performance measurement system for knowledge strategies based on Balanced Scorecard, and simulates the system with an improved Data Envelopment Analysis (DEA) model.展开更多
The paper presents selected experience of the authors resulting from the optimization tests of double-regulated water turbines. Among the methods for measuring the discharge through the turbine used in such tests, par...The paper presents selected experience of the authors resulting from the optimization tests of double-regulated water turbines. Among the methods for measuring the discharge through the turbine used in such tests, particular attention was paid to index methods allowing to measure the relative discharge through the turbine-the index current meter method and the methods based on measuring the differential pressure between two points properly located at the turbine flow system (i.e., Winter-Kennedy method). These methods contribute to effective reduction of the cost of optimizing the turbine that is extremely important for small hydropower plants regarding installed capacity. The paper presents selected examples of the optimization tests and experiences that arise from these tests.展开更多
We present the analysis of three independent and most widely used image smoothing techniques on a new fractional based convolution edge detector originally constructed by same authors for image edge analysis. The impl...We present the analysis of three independent and most widely used image smoothing techniques on a new fractional based convolution edge detector originally constructed by same authors for image edge analysis. The implementation was done using only Gaussian function as its smoothing function based on predefined assumptions and therefore did not scale well for some types of edges and noise. The experiments conducted on this mask using known images with realistic geometry suggested the need for image smoothing adaptation to obtain a more optimal performance. In this paper, we use the structural similarity index measure and show that the adaptation technique for choosing smoothing function has significant advantages over a single function implementation. The new adaptive fractional based convolution mask can smoothly find edges of various types in detail quite significantly. The method can now trap both local discontinuities in intensity and its derivatives as well as locating Dirac edges.展开更多
Experimental techniques for measurement of optical penetration depth and refractive index of human tissue are presented, respectively. Optical penetration depth can be obtained from the measurement of the relative flu...Experimental techniques for measurement of optical penetration depth and refractive index of human tissue are presented, respectively. Optical penetration depth can be obtained from the measurement of the relative fluencc-depth distribution inside the target tissue. The depth of normal and carcinomatous human lung tissues irradiated with the wavelengths of 406.7, 632.8 and 674.4 nm in vitro are respectively determined. In addition, a novel simple method based on total internal reflection for measuring the refractive index of biotissue in vivo is developed, and the refractive indices of skin from people of different age, sex and skin color are measured. Their refractive indices are almost same and the average is 1.533.展开更多
A fiber in-line Fabry-Perot interferometer is presented. The sensing head consists of a micro ellipsoidal air cavity and a small section of solid-core photonic crystal fiber. The reflective index (RI) and temperatur...A fiber in-line Fabry-Perot interferometer is presented. The sensing head consists of a micro ellipsoidal air cavity and a small section of solid-core photonic crystal fiber. The reflective index (RI) and temperature can be interrogated simultaneously through a fast Fourier transform and by tracing the dip wavelength shift of the reflective spectrum. Experimental results show that the RI amplitude and wavelength sensitivities are 5.30/ RIU and 8.46 × 10-1 nm/RIU in the range from 1.34 to 1.43, and the temperature amplitude and wavelength sensitivities are 6.8 × 10-4/℃ and 2.48 × 10-3 nm/℃ in the range from 15℃ to 75℃, respectively. Easy fabrication, a simple system, and simultaneous measurement make it appropriate for aluM-parameter sensing application.展开更多
The classical probabilistic reliability theory and fuzzy reliability theory cannot directly measure the uncertainty of structural reliability with uncertain variables, i.e., subjective random and fuzzy variables. In o...The classical probabilistic reliability theory and fuzzy reliability theory cannot directly measure the uncertainty of structural reliability with uncertain variables, i.e., subjective random and fuzzy variables. In order to simultaneously satisfy the duality of randomness and subadditivity of fuzziness in the reliability problem, a new quantification method for the reliability of structures is presented based on uncertainty theory, and an uncertainty-theory-based perspective of classical Cornell reliability index is explored. In this paper, by introducing the uncertainty theory, we adopt the uncertain measure to quantify the reliability of structures for the subjective probability or fuzzy variables, instead of probabilistic and possibilistic measures. We utilize uncertain variables to uniformly represent the subjective random and fuzzy parameters, based on which we derive solutions to analyze the uncertainty reliability of structures with uncertainty distributions. Moreover, we propose the Cornell uncertainty reliability index based on the uncertain expected value and variance.Experimental results on three numerical applications demonstrate the validity of the proposed method.展开更多
基金Supported by Hebei Provincial Science&Technology Department Soft Sciences Research Program (10457204D-18)
文摘Taking the mechanism of technological construction guidance theory and mode which consists of "objective-construction-evaluation-construction-objective" as a starting point, on the basis of county agricultural technological innovation ability and its index definition, this paper researches the constructing system of county agricultural technological innovation ability. Firstly, on the basis of defining county agricultural technological innovation ability and the definition of index, according to the principle of purposefulness, scientificity, systematicness, integration of dynamic state and static state, integration of quantitativeness and qualitativeness and so on, we construct the multi-level measuring system of county agricultural technological innovation ability, including 4 first-level indices, namely technological innovation environment, technological innovation basis, technological innovation ability, and technological innovation efficiency; 15 second-level indices, such as technological policy, technological system mechanism, technological institution construction, ability of innovation subject, ability of industrial expansion, scale merit, technological contribution rate. Moreover, this system has 45 third-level indices. Then, by using unascertained mathematics method and AHM method, we establish the multi-level unascertained composite measuring model of county agricultural technological innovation ability index. Finally, by using the survey data of one county in Hebei Province, and the established county agricultural technological innovation ability index model, we get the county agricultural technological innovation ability index of 0.711 by calculation, that is, the innovation ability is at the intermediate level, namely the modern agricultural sub-stage. The empirical research proves the correctness and applicability of this model.
基金National Natural Science Foundation of China(No.61405127)Shanxi Province Science Foundation for Youths(No.2014021023-1)+1 种基金Scientific and Technologial Innovation Programs of Higher Education Institutions in Shanxi ProvinceProgram for Top Young Academic Leaders of Higher Learning Institutions in Shanxi Province
文摘In order to detect the refractive index of liquid with high precision,based on modular interference,Mach-Zehnder optical fiber refractive rate sensor was studied.Sensor structure is composed of ordinary single-mode fiber and multimode fiber,according to the singlemode multimode singlemode sequence to fuse together,and the fused optical fiber is used to process the taper.As a result,the diameter of the sensing head is about 10μm.Experimental results show that,as liquid refractive index increases range from 1.33 to 1.35,the loss peak of the transmission spectrum will shift to long wave direction.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61775182 and 61505165)Marie Sktodowska-Curie Individual Fellowships in the European Union’s Horizon 2020 Research and Innovation Programme(Grant No.660648)
文摘We proposed and experimentally demonstrated a cascaded tilted fiber Bragg grating(TFBG)for enhanced refractive index sensing.The TFBG is UV-inscribed in series in ordinary single-mode fiber(SMF)and reduced-diameter SMF with the same tilt angle,and then excites two sets of superposed spectral combs of cladding modes.The cascaded TFBG with total length of 18 mm has a much wider wavelength range over 100 nm and narrower wavelength separation than that of a TFBG only in the SMF,enabling an enlarged range and a higher accuracy of refractive index measurement.The fabricated TFBG with the merits of enhanced sensing capability and temperature self-calibration presents great potentials in the biochemical sensing applications.
基金Supported by the National Natural Science Foundation of China under Grant No 61036016the Beijing Higher Education Young Elite Teacher Project under Grant No YETP0086
文摘Wavelength 1064 nm is one of the most widely used laser wavelengths in industries and science. The high-precision measurement of the refractive index of optical materials at 1064 nm is significant for improving the optical design. We study the direct measurement of refractive index at 1064nm of lasers, including cMcium fluoride (CaF2), fused silica and zinc selenide (ZnSe), whose refractive indices cover a large range from 1.42847 to 2.48272. The measurement system is built based on the quasi-common-path Nd:YAG laser feedback interferometry. The thickness can be measured simultaneously with the refractive index. The results demonstrate that the system has absolute uncertainties of ~10-5 and ~10-4 mm in refractive index and thickness measurement, respectively.
基金Supported by the National Natural Science Foundation of China under Grant No F050306
文摘We present the thermal expansion coefficient (TEC) measurement technology of compensating for the effect of variations in the refractive index based on a Nd: YA G laser feedback system, the beam frequency is shifted by a pair of aeousto-optic modulators and then the heterodyne phase measurement technique is used. The sample measured is placed in a muffle furnace with two coaxial holes opened on the opposite furnace walls. The measurement beams hit perpendicularly and coaxially on each surface of the sample. The reference beams hit on the reference mirror and the high-refiectivity mirror, respectively. By the heterodyne configuration and computing, the influences of the vibration, distortion of the sample supporter and the effect of variations in the refractive index are measured and largely minimized. For validation, the TECs of aluminum samples are determined in the temperature range of 29-748K, confirming not only the precision within 5 × 10-7 K-1 and the accuracy within 0.4% from 298K to 448K but also the high sensitivity non-contact measurement of the lower reflectivity surface induced by the sample oxidization from 448 K to 748 K.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61327012 and 61505160the Natural Science Foundation of Shaanxi Province under Grant No 2016JQ6021the Shaanxi Key Laboratory of Optical Information Technology under Grant No OIT201601
文摘A refractive index (RI) sensor based on hybrid long-period fiber grating (LPFG) with multimode fiber core (MMFC) is proposed and demonstrated. The surrounding RI can be determined by monitoring the separation between the resonant wavelengths of the LPFG and MMFC since the resonant wavelengths of the LPFG and MMFC will shift in opposite directions when the surrounding RI changes. Experimental results show that the sensor possesses an enhanced sensitivity of 526.92nm/RIU in the RI range of 1.387-1.394 RIU. The response to the temperature is also discussed.
基金This work is supported by the Natural Science Foundation of HebeiPi rovincee(GranttNos.F2023501008 and F2020501040)the Fundamental Research Funds for the Central Universities(Grant No.N2323017)+1 种基金the National Natural Science Foundation of China(Grant No.62005186)the Engineeringg Featured Team Fund of Sichuan University(Grant No.2020SCUNG105).
文摘In this paper,a new concept of forward-pumped random Raman fiber laser(RRFL)-based liquid refractive index sensing is proposed for the first time.For liquid refractive index sensing,the flat fiber end immersed in the liquid can act as the point reflector for generating random fiber lasing and also as the sensing head.Due to the high sensitivity of the output power of the RRFL to the reflectivity provided by the point reflector in the ultralow reflectivity regime,the proposed RRFL is capable of achieving liquid refractive index sensing by measuring the random lasing output power.We theoretically investigate the effects of the operating pump power and fiber length on the refractive index sensitivity for the proposed RRFL.As a proof-of-concept demonstration,we experimentally realize high-sensitivity half-open short-cavity RRFL-based liquid refractive index sensing with the maximum sensitivity and the sensing resolution of-39.88W/RIU and 2.5075×10^(-5) RIU,respectively.We also experimentally verify that the refractive index sensitivity can be enhanced with the shorter fiber length of the RRFL.This work extends the application of the random fiber laser as a new platform for highly-sensitive refractive index sensing in chemical,biomedical,and environmental monitoring applications,etc.
基金supported by the National Natural Science Foundation of China(Nos.62075001 and 61675010)the Science Foundation of Education Commission of Beijing(No.KZ202010005008)the Beijing Nova Program(No.XX2018072)。
文摘Three-dimensional(3D)refractive index(RI)distribution is important to reveal the object’s inner structure.We implemented terahertz(THz)diffraction tomography with a continuous-wave single-frequency THz source for measuring 3D RI maps.The off-axis holographic interference configuration was employed to obtain the quantitative scattered field of the object under each rotation angle.The 3D reconstruction algorithm adopted the filtered backpropagation method,which can theoretically calculate the exact scattering potential from the measured scattered field.Based on the Rytov approximation,the 3D RI distribution of polystyrene foam spheres was achieved with high fidelity,which verified the feasibility of the proposed method.
基金Supported by Sichuan Beef Cattle Innovation Team Building of National Modern Agricultural industrial Technology System(SCCXTD-2022-13)Sichuan Science and Technology Planning Project(2021YFYZ0001).
文摘[Objectives]In order to better understand the performance of Kongshan cattle,their growth and development was analyzed.[Methods]The body weights of 106 kongshan cattle at different month ages were measured,and the growth curves and body measurement indices of Kongshan cattle after one year old were analyzed by SPPS18.0.[Results]Kongshan cattle have good body shape.Compared with 1985,the performance of body measurements and weight was improved significantly;and the body measurements and body weight of Kongshan cattle increased significantly after 24 months old,indicating that Kongshan cattle still have good fattening performance in adulthood.[Conclusions]This study analyzed the growth and development laws of Kongshan cattle and the status quo of the population,and will provide some help for the selection and utilization of Kongshan cattle breed more intuitively.
基金support from the National Nature Science Foundation of China (Grants 11372305 and 11002138)K.C. Wong Education Foundation for a Royal Society K.C. Wong Postdoctoral Fellowship
文摘Self-excited oscillation in a collapsible tube is an important phenomenon in physiology. An experimental approach on self-excited oscillation in a thin-walled collapsi- ble tube is developed by using a high transmittance and low Young's modulus silicone rubber tube. The elastic tube is manufactured by the method of centrifugal casting in our laboratory. An optical method for recording the evolution of the cross-sectional areas at a certain position along the longitudinal direction of the tube is developed based on the technology of refractive index matching. With the transparent tube, the tube law is measured under the static no-flow condition. The cross section at the middle position of the tube transfers from a quasi-circular configuration to an ellipse, and then to a dumbell-shape as the chamber pressure is increased. During the self-excited oscillation, two periodic self-excited oscillating states and one transitional oscillating state are identified. They all belong to the LU mode. These different oscillating states are related to the initial cross-sectional shape of the tube caused by the difference of the downstream transmural pressure.
文摘Vulnerability technology is the basic of network security technology,vulnerability quantitative grading methods,such as CVSS,WIVSS,ICVSS,provide a reference to vulnerability management,but the problems of ignoring the risk elevation caused by a group of vulnerabilities and low accuracy of exploitable level evaluation exist in current vulnerability quantitative grading methods.To solve problems above in current network security quantitative evaluation methods,this paper verified the high relevance degree between type and exploitable score of vulnerability,proposed a new vulnerability quantitative grading method ICVSS,ICVSS can explore attack path using continuity level defined by privilege,add vulnerability type to measure indexes of exploitable metrics and use Analytic Hierarchy Process(AHP)to quantify the influence of vulnerability type on exploitable level.Compared with CVSS and WIVSS,ICVSS is proved that it can discover attack path consist of a sequence of vulnerabilities for network security situation evaluation,and has more accuracy and stability.
基金funding from the National Science and Technology Support Program of China(2008BADB2B08)Science and Technology Service Platform of Jiangsu Province ( BM2008170)
文摘[ Objective] To study the meat production performance of geese in different crossbred combination, and provide a reference for cultivating new multiplication strains of meat geese. [Method] A total of five goose breeds including Taihu goose (T), Wulong goose (WL), Wanxi white goose (WX), Sichuan white goose (SC) and Sanhua goose (SH) were used as research objects, and eight crossbred combinations were designed. The body measurements, slaughter performance, conventional meat quality and muscle composition of 90-day-old geese in eight crossbred combinations were determined and comparatively analyzed. [ Result] All the body measurement indexes except thud width of WXSC combination were the biggest in the eight crossbred combinations. Contrarily, the body measurement indexes of SHSC combination, including average body weight, body slope length, breast depth, breast width, shank length, neck length and half-diving depth were the lowest in the eight crossbred combinations. The live weight, slaughter weight and abdomen fat weight of WXSC combinations ware 3 291.36, 2 956.46 and 77.84 g, respectively, which were the biggest in eight crossbred combinations. The slaughter rate of SHWL combinations was 92.96%, and more than other crossbred combinations. The shear force of SHT and WXWL combinations were the lowest (3.09 kg) and the highest (3.78 kg), respectively. The water holding capacities of SCWL and WXSC combinations were the highest (66.46%) and the lowest (61.48%), respectively. The percentage of moisture content of SHWL and SCT combinations were the highest (73.05%) and the lowest (66.77%), respectively. The crude protein content of SHT and SHWL combinations were the highest (23.32%) and the lowest (21.94%), respectively. The percentage of crude fat content of SHT and SCWL combinations were the highest (3.06%) and the lowest (1.67%), respectively. [ Concusion] The growth rate of WXSC combination is the fastest, and the meat performance of SHT combination is the best.
文摘Advanced technology used for arithmetic computing application,comprises greater number of approximatemultipliers and approximate adders.Truncation and Rounding-based Scalable ApproximateMultiplier(TRSAM)distinguish a variety of modes based on height(h)and truncation(t)as TRSAM(h,t)in the architecture.This TRSAM operation produces higher absolute error in Least Significant Bit(LSB)data shift unit.A new scalable approximate multiplier approach that uses truncation and rounding TRSAM(3,7)is proposed to increase themultiplier accuracy.With the help of foremost one bit architecture,the proposed scalable approximate multiplier approach reduces the partial products.The proposed approximate TRSAM multiplier architecture gives better results in terms of area,delay,and power.The accuracy of 95.2%and the energy utilization of 24.6 nJ is observed in the proposed multiplier design.The proposed approach shows 0.11%,0.23%,and 0.24%less Mean Absolute Relative Error(MARE)when compared with the existing approach for the input of 8-bit,16-bit,and 32-bit respectively.It also shows 0.13%,0.19%,and 0.2%less Variance of Absolute Relative Error(VARE)when compared with the existing approach for the input of 8-bit,16-bit,and 32-bit respectively.The proposed approach is implemented with Field-Programmable Gate Array(FPGA)and shows the delay of 3.640,6.481,12.505,22.572,and 36.893 ns for the input of 8-bit,16-bit,32-bit,64-bit,and 128-bit respectively.The proposed approach is applied in digital filters designwhich shows the Peak-Signal-to-NoiseRatio(PSNR)of 25.05 dB and Structural Similarity Index Measure(SSIM)of 0.98 with 393 pJ energy consumptions when used in image application.The proposed approach is simulated with Xilinx and MATLAB and implemented with FPGA.
文摘The collaboration tools offered by Cloud Computing have increased the need to share data and services within companies or between autonomous organizations. This has led to the deployment of community cloud infrastructures. However, several challenges will arise from this grouping of heterogeneous organizations. One of the main challenges is the management of trust between the actors of the community. Trust issues arise from the uncertainty about the quality of the resources and entities involved. The quality of a resource can be examined from a security or functional perspective. Therefore, ensuring security and monitoring the quality of resources is to ensure a high level of trust. Therefore, we propose in this paper a technique for dynamic trust management and quality monitoring of resources shared between organizations. Our approach consists, on the one hand, in evaluating the quality of resources based on quality of service measurement attributes and, on the other hand, in updating the trust values according to the information deduced from these measurements. The proposed framework is evaluated in terms of resource sharing success rate and execution time. Experimental results and comparison with TNA-SL and InterTrust models show that the framework can identify and track the behavior of malicious organizations with relatively low execution time.
文摘Knowledge has become the most important strategic resource of firms, and the competition among firms is more based on knowledge than before. To deal with this challenge, some firms are trying to develop knowledge strategies to direct their knowledge management activities, but current strategic performance measurement systems can't evaluate the performance of knowledge strategies appropriately. This article develops a performance measurement system for knowledge strategies based on Balanced Scorecard, and simulates the system with an improved Data Envelopment Analysis (DEA) model.
文摘The paper presents selected experience of the authors resulting from the optimization tests of double-regulated water turbines. Among the methods for measuring the discharge through the turbine used in such tests, particular attention was paid to index methods allowing to measure the relative discharge through the turbine-the index current meter method and the methods based on measuring the differential pressure between two points properly located at the turbine flow system (i.e., Winter-Kennedy method). These methods contribute to effective reduction of the cost of optimizing the turbine that is extremely important for small hydropower plants regarding installed capacity. The paper presents selected examples of the optimization tests and experiences that arise from these tests.
文摘We present the analysis of three independent and most widely used image smoothing techniques on a new fractional based convolution edge detector originally constructed by same authors for image edge analysis. The implementation was done using only Gaussian function as its smoothing function based on predefined assumptions and therefore did not scale well for some types of edges and noise. The experiments conducted on this mask using known images with realistic geometry suggested the need for image smoothing adaptation to obtain a more optimal performance. In this paper, we use the structural similarity index measure and show that the adaptation technique for choosing smoothing function has significant advantages over a single function implementation. The new adaptive fractional based convolution mask can smoothly find edges of various types in detail quite significantly. The method can now trap both local discontinuities in intensity and its derivatives as well as locating Dirac edges.
基金This work was supported by the National Natural Science Foundation of China under Grant No.60178022the Fujian Provincial Natural Science Foundation under Grant No.2002F008.
文摘Experimental techniques for measurement of optical penetration depth and refractive index of human tissue are presented, respectively. Optical penetration depth can be obtained from the measurement of the relative fluencc-depth distribution inside the target tissue. The depth of normal and carcinomatous human lung tissues irradiated with the wavelengths of 406.7, 632.8 and 674.4 nm in vitro are respectively determined. In addition, a novel simple method based on total internal reflection for measuring the refractive index of biotissue in vivo is developed, and the refractive indices of skin from people of different age, sex and skin color are measured. Their refractive indices are almost same and the average is 1.533.
基金supported by the National Natural Science Foundation of China(Nos.61178044 and 51405240)the Natural Science Foundation of Jiangsu Province of China(No.BK20140925)+2 种基金the Major Project of the Nature Science Research for Colleges and Universities in Jiangsu Province(No.15KJA140002)the Program of Natural Science Research of the Jiangsu Higher Education Institutions of China(No.14KJB510015)the University Postgraduate Research and Innovation Project of Jiangsu Province(No.1812000002A422)
文摘A fiber in-line Fabry-Perot interferometer is presented. The sensing head consists of a micro ellipsoidal air cavity and a small section of solid-core photonic crystal fiber. The reflective index (RI) and temperature can be interrogated simultaneously through a fast Fourier transform and by tracing the dip wavelength shift of the reflective spectrum. Experimental results show that the RI amplitude and wavelength sensitivities are 5.30/ RIU and 8.46 × 10-1 nm/RIU in the range from 1.34 to 1.43, and the temperature amplitude and wavelength sensitivities are 6.8 × 10-4/℃ and 2.48 × 10-3 nm/℃ in the range from 15℃ to 75℃, respectively. Easy fabrication, a simple system, and simultaneous measurement make it appropriate for aluM-parameter sensing application.
基金co-supported by the National Natural Science Foundation of China (Nos. 51675026 and 71671009)the National Basic Research Program of China (No. 2013CB733002)
文摘The classical probabilistic reliability theory and fuzzy reliability theory cannot directly measure the uncertainty of structural reliability with uncertain variables, i.e., subjective random and fuzzy variables. In order to simultaneously satisfy the duality of randomness and subadditivity of fuzziness in the reliability problem, a new quantification method for the reliability of structures is presented based on uncertainty theory, and an uncertainty-theory-based perspective of classical Cornell reliability index is explored. In this paper, by introducing the uncertainty theory, we adopt the uncertain measure to quantify the reliability of structures for the subjective probability or fuzzy variables, instead of probabilistic and possibilistic measures. We utilize uncertain variables to uniformly represent the subjective random and fuzzy parameters, based on which we derive solutions to analyze the uncertainty reliability of structures with uncertainty distributions. Moreover, we propose the Cornell uncertainty reliability index based on the uncertain expected value and variance.Experimental results on three numerical applications demonstrate the validity of the proposed method.