The conventional mono-station passive location techniques of direction finding are low in speed and accuracy, due to the little information available. In this paper, a novel measurement-rate (derivative) of phase diff...The conventional mono-station passive location techniques of direction finding are low in speed and accuracy, due to the little information available. In this paper, a novel measurement-rate (derivative) of phase difference from a two-element antenna array (interferometer) is introduced, accuracy of a passive location system with this measurement and directions of arrival (DOA) is analyzed, and the Cramer-Rao bound of location error of this system for 3D location is examined by simulations.展开更多
Apoptosis proteins play an important role in the development and homeostasis of an organism. The elucidation of the subcellular locations and functions of these proteins is helpful for understanding the mechanism of p...Apoptosis proteins play an important role in the development and homeostasis of an organism. The elucidation of the subcellular locations and functions of these proteins is helpful for understanding the mechanism of programmed cell death. In this paper, the recurrent quantification analysis, Hilbert-Huang transform methods, the maximum relevance and minimum redundancy method and support vector machine are used to predict the subcellular location of apoptosis proteins. The validation of the jackknife test suggests that the proposed method can improve the prediction accuracy of the subcellular location of apoptosis proteins and its application may be promising in other fields.展开更多
Many products always operate under various complex environment conditions. To describe the dynamic influence of environment factors on their reliability, a method of reliability sensitivity analysis is proposed. In th...Many products always operate under various complex environment conditions. To describe the dynamic influence of environment factors on their reliability, a method of reliability sensitivity analysis is proposed. In this method, the location parameter is assumed as a function of relevant environment variables while the scale parameter is assumed as an unknown positive constant. Then, the location parameter function is constructed by using the method of radial basis function. Using the varied environment test data, the log-likelihood function is transformed to a generalized linear expression by describing the indicator as Poisson variable. With the generalized linear model, the maximum likelihood estimations of the model coefficients are obtained. With the reliability model, the reliability sensitivity is obtained. An instance analysis shows that the method is feasible to analyze the dynamic variety characters of reliability along with environment factors and is straightforward for engineering application.展开更多
According to the statistical data in the years 2004-2008, both Shift-Share Analysis and Location Quotient Analysis are used to compare the economic development status of counties (districts) in Dingxi City in the year...According to the statistical data in the years 2004-2008, both Shift-Share Analysis and Location Quotient Analysis are used to compare the economic development status of counties (districts) in Dingxi City in the years 2004 and 2008. Advantages and disadvantages of industrial structure and competitiveness are analyzed, as well as the impacts of existing industrial structure on economic growth. Development direction and development focus of primary, secondary and tertiary industries are found out. Countermeasures for accelerating the economic development of counties (districts) in Dingxi City are put forward, such as increasing the inputs in characteristic agriculture, promoting the development of primary industry, speeding up the construction of large and medium industrial enterprises, enhancing the development of secondary industry, strengthening comprehensive environmental improvement in tourist area, and actively developing tertiary industry.展开更多
The application of geospatial analysis is a need to respond to the increasing number of social conflicts caused by the existence of public places of worships (PPW) in Indonesia. This conflict eventually becomes endemi...The application of geospatial analysis is a need to respond to the increasing number of social conflicts caused by the existence of public places of worships (PPW) in Indonesia. This conflict eventually becomes endemic among Indonesian cross-cultural society. Even though the government has produced a regulation-like policy namely SKB 2006 to manage the establishment of PPW, its contribution to avoiding or reducing the conflicts is in question. Researchers notice that the policy is misused in some incidents to even trigger the conflict. It is due to the presence of people participation defined in SKB 2006 particularly to determine the legalization of PPW. Currently there is no exact foundation used by the government to precisely measure the status of PPW, hence the decision to permit or reject any proposal to establish PPW is determined by the acceptance of surrounding society which in many occasions becomes the cause of the conflict. Therefore the government needs to regain control over the existence of PPW since these types of buildings are public facilities used by people in cross-cultural society. The research is to provide accurate information regarding the existence of PPW and the impact of their presence using geospatial analysis. The objective is to analyze the interaction between PPW and its surrounding objects. The analysis is based on PPW coverage, overlapping and blank spot area. A case study has been conducted to analyze the existence of PPW at Cemorokandang village, a part of Malang city in the province of East Java. The application highlights the issue of overwhelming PPW in the location of analysis.展开更多
In the process of rapid industrialization and urbanization,the phenomenon of migrant workers’return accompanied its flow is attracting more and more attention of scholars.Based on the sampling data of 529 migrant wor...In the process of rapid industrialization and urbanization,the phenomenon of migrant workers’return accompanied its flow is attracting more and more attention of scholars.Based on the sampling data of 529 migrant workers’return questionnaires,statistical analysis and binary logistic model were used to analyze the return location choice and influencing factors of migrant workers.The study found that the village,the local township and the local county seat are the main choices for the inter-provincial migrant workers of return location.The local township and the local county seat are also the preferred locations for migrant workers to return to business,while in the city and other city are less migrant workers.The main mechanism for the choice of migrant workers of return location is the balance between the family and the economic benefits.The main factors affecting the choice of rural migrant workers’return location are the age of migrant workers,the number of primary and secondary school students,the number of migrant workers,and the per capita cultivated area.The mobility and return of migrant workers are actually the location choices and changes of migrant workers in geospatial space,which depends on the sticky size of different locations.展开更多
Due to the problem complexity, simultaneous solution methods are limited. A hybrid algorithm is emphatically proposed for LRP. First, the customers are classified by clustering analysis with preference-fitting rules. ...Due to the problem complexity, simultaneous solution methods are limited. A hybrid algorithm is emphatically proposed for LRP. First, the customers are classified by clustering analysis with preference-fitting rules. Second, a chaos search (CS) algorithm for the optimal routes of LRP scheduling is presented in this paper. For the ergodicity and randomness of chaotic sequence, this CS architecture makes it possible to search the solution space easily, thus producing optimal solutions without local optimization. A case study using computer simulation showed that the CS system is simple and effective, which achieves significant improvement compared to a recent LRP with nonlinear constrained optimization solution. Lastly the pratical anlysis is presented relationship with regional logistics and its development in Fujian province.展开更多
Ozonolysis products of four lepidopteral pheromone were identified by methane CI-MS.The spectra obtained were notably simpler than those of EI-MS,the peak of molecular ion was normally close to the base peak,and the c...Ozonolysis products of four lepidopteral pheromone were identified by methane CI-MS.The spectra obtained were notably simpler than those of EI-MS,the peak of molecular ion was normally close to the base peak,and the characteristic fragment ions were high in m/z,thereby the interpretation was facilitated.展开更多
The location of the distribution facilities and the routing of the vehicles from these facilities are interdependent in many distribution systems. Such a concept recognizes the interdependence;attempts to integrate th...The location of the distribution facilities and the routing of the vehicles from these facilities are interdependent in many distribution systems. Such a concept recognizes the interdependence;attempts to integrate these two decisions have been limited. Multi-objective location-routing problem (MLRP) is combined with the facility location and the vehicle routing decision and satisfied the different objectives. Due to the problem complexity, simultaneous solution methods are limited, which are given in different objectives with conflicts in functions satisfied. Two kinds of optimal mathematical models are proposed for the solution of MLRP. Three methods have been emphatically developed for MLRP. MGA architecture makes it possible to search the solution space efficiently, which provides a path for searching the solution with two-objective LRP. At last the practical proof is given by random analysis for regional distribution with nine cities.展开更多
To solve the problem of multiple moving sources passive location,a novel blind source separation(BSS) algorithm based on the multiset canonical correlation analysis(MCCA) is presented by exploiting the different tempo...To solve the problem of multiple moving sources passive location,a novel blind source separation(BSS) algorithm based on the multiset canonical correlation analysis(MCCA) is presented by exploiting the different temporal structure of uncorrelated source signals first,and then on the basis of this algorithm,a novel multiple moving sources passive location method is proposed using time difference of arrival(TDOA) and frequency difference of arrival(FDOA) measurements.The key technique of this location method is TDOA and FDOA joint estimation,which is based on BSS.By blindly separating mixed signals from multiple moving sources,the multiple sources location problem can be translated to each source location in turn,and the effect of interference and noise can also be removed.The simulation results illustrate that the performance of the MCCA algorithm is very good with relatively light computation burden,and the location algorithm is relatively simple and effective.展开更多
For the joint time difference of arrival(TDOA) and angle of arrival(AOA) location scene,two methods are proposed based on the rectangular coordinates and the polar coordinates,respectively.The problem is solved pe...For the joint time difference of arrival(TDOA) and angle of arrival(AOA) location scene,two methods are proposed based on the rectangular coordinates and the polar coordinates,respectively.The problem is solved perfectly by calculating the target position with the joint TDOA and AOA location.On the condition of rectangular coordinates,first of all,it figures out the radial range between target and reference stations,then calculates the location of the target.In the case of polar coordinates,first of all,it figures out the azimuth between target and reference stations,then figures out the radial range between target and reference stations,finally obtains the location of the target.Simultaneously,simulation analyses show that the theoretical analysis is correct,and the proposed methods also provide the application of the joint TDOA and AOA location algorithm with the theoretical basis.展开更多
Homeobox transcription factors participate in the growth and development of plants by regulating cell differentiation, morphogenesis and environmental signal response. To reveal the functions of these transcription fa...Homeobox transcription factors participate in the growth and development of plants by regulating cell differentiation, morphogenesis and environmental signal response. To reveal the functions of these transcription factors in rice, we constructed the RNAi vectors of OsHox9, a member of homeobox family, and analyzed the function of OsHox9 using reverse genetics. The plant height and tillering number of RNAi transgenic plants decreased compared with those of wild-type plants. Reverse transcdption-polymerase chain reaction analysis showed that OsHox9 expression reduced in the transgenic plants with phenotypic variance, whereas that in the transgenic plants without phenotypic variance was similar to that in the wild-type plants. This result suggests that the phenotypes of the transgenic plants were caused by RNAi effects. The tissue-specificity of OsHox9 expression indicated that it was expressed in different organs, with high expression in stem apical medstem and young panicles. Subcellular location of OsHox9 demonstrated that it was localized on the cell membrane.展开更多
The location pattern of different commercial stores in Shichahai, a historic conservation area in Beijing, was investigated from a street centrality perspective. Many previous studies have investigated the relationshi...The location pattern of different commercial stores in Shichahai, a historic conservation area in Beijing, was investigated from a street centrality perspective. Many previous studies have investigated the relationship between street centrality and land use patterns or commercial activities at interurban or intraurban scales. We considered Shichahai in this study to determine if street centrality applied at the street scale and if the street network was the only factor influencing the selection of store location. First, the nearest neighbor index, nearest neighbor hierarchical spatial cluster(NNHSC), and kernel density estimation(KDE) methods were used to provide baseline spatial distributions of commercial stores. Second, urban network analysis(UNA) tools were used to measure the street centrality indices under two conditions, with and without the weighting of cultural relics calculated by a principal component analysis(PCA). Finally, both store locations and centrality values at nodes were transformed to one unit(raster pixel) for a correlation analysis.The results showed that three of the four store types were clustered and had their own hotspots that were mostly located in the eastern and central parts of city blocks. The most momentous findings were determined from the street centrality indices. Among the three store types with correlation coefficients above 0.5, all centrality indices with landmark weighting, except straightness, had higher correlations,with closeness with landmark weighting having the highest correlation, followed by betweenness with landmark weighting. Therefore,we statistically concluded that street centrality could apply at the street scale and that the street network was not the only factor that influenced store location pattern, with landmarks also playing a significant role. The results provide guidance in determining the selection strategy for stores in a historic conservation area.展开更多
For the high-speed gasoline engine turbocharger rotor, due to the heterogeneity of multiple parts material, manufacturing and assembly errors, running wear in impeller and uneven carbon of turbine, the random unbalanc...For the high-speed gasoline engine turbocharger rotor, due to the heterogeneity of multiple parts material, manufacturing and assembly errors, running wear in impeller and uneven carbon of turbine, the random unbalance usually can be developed which will induce excessive rotor vibration, and even lead to nonlinear vibration accidents. However, the investigation of unbalance location on the nonlinear high-speed turbocharger rotordynamic characteristics is less. In order to discuss the rotor unbalance location effects of turbocharger with nonlinear floating ring bearings(FRBs), the realistic turbocharger of gasoline engine is taken as a research object. The rotordynamic equations of motion under the condition of unbalance are derived by applied unbalance force and nonlinear oil film force of FRBs. The FE model of turbocharger rotor-bearing system is modeled which includes the unbalance excitation and nonlinear FRBs. Under the conditions of four different applied locations of unbalance, the nonlinear transient analyses are performed based on the rotor FEM. The differences of dynamic behavior are obvious to the turbocharger rotor systems for four conditions, and the bifurcation phenomena are different. From the results of waterfall and transient response analysis, the speed for the appearance of fractional frequency is not identical and the amplitude magnitude is different from the different unbalance locations, and the non-synchronous vibration does not occur in the turbocharger and the amplitude is relative stable and minimum under the condition 4. The turbocharger vibration and non-synchronous components could be reduced or suppressed by controlling the applied location of unbalance, which is helpful for the dynamic design, fault diagnosis and vibration control of the high-speed gasoline engine turbochargers.展开更多
Grain size, determined chiefly by grain length, is one of the main factors affecting the grain yield in rice production. To study the trait of rice grain size, F1 and F2 populations were developed from crosses Shuhui ...Grain size, determined chiefly by grain length, is one of the main factors affecting the grain yield in rice production. To study the trait of rice grain size, F1 and F2 populations were developed from crosses Shuhui 881/Y34 and Shuhui 527/Y34, and genetic analysis for minute grain was performed. The F1 populations showed minute grains, and grain size segregations in the two F2 populations were both in accordance with the ratio of 3:1, indicating that minute grain in Y34 was controlled by a completely dominant gene. By using the F2 population from Shuhui 881/Y34, this dominant gene, tentatively designated as Mi3(t), was mapped based on SSR markers in the interval between RM282 (genetic distance of 5.1 cM) and RM6283 (genetic distance of 0.9 cM) on the short arm of chromosome 3.展开更多
Summary:Several studies have indicated that stroke survivors with multiple lesions or with larger lesion volumes have a higher risk of stroke recurrence.However,the relationship between lesion locations and stroke rec...Summary:Several studies have indicated that stroke survivors with multiple lesions or with larger lesion volumes have a higher risk of stroke recurrence.However,the relationship between lesion locations and stroke recurrence is unclear.We conducted a prospective cohort study of first-ever ischemic stroke survivors who were consecutively enrolled from January 2010 to December 2015.Stroke recurrence was assessed every 3 months after post-discharge via telephone interviews by trained interviewers.Lesion locations were obtained from hospital-based MRI or CT scans and classified using two classification systems that were based on cerebral hemisphere or vascular territory and brain anatomical structures.Flexible parametric survival models using the proportional hazards scale(PH model)were used to analyze the time-to-event data.Among 633 survivors,63.51%(n-402)had anterior circulation ischemia(ACI),and morc than half of all ACIs occurred in the subcortex.After a median follow-up of 2.5 years,117(18.48%)survivors developed a recurrent stroke.The results of the multivariate PH model showed that survivors with non-brain lesions were at higher risk of recurrence than those with right-side lesions(HR,2.79;95%CI,1.53,5.08;P-0.001).There was no increase in risk among survivors with left-side lesions(HR,0.97;95%CI,0.53,1.75;P=0.914)or both-side lesions(HR,1.24;95%CI,0.75,2.07;P-0.401)compared to those with right-side lesions.Additionally,there were no associations between stroke ecurrence and lesion locations that were classified based on vascular territory and brain anatomical structures.It was concluded that first-ever ischemic stroke survivors with non-brain lesion had higher recurrence risk than those with right-side lesion,although no significant associations were found when the lesion locations were classified by vascular territory and brain anatomical structures.展开更多
Location Based Navigation System (LBNS) is a specific Location Based Service (LBS) purely for navigational purpose. These systems resolve position of a user by using GNSS/GPS positioning technologies, to which supplem...Location Based Navigation System (LBNS) is a specific Location Based Service (LBS) purely for navigational purpose. These systems resolve position of a user by using GNSS/GPS positioning technologies, to which supplementary information on goods and services are tagged. The navigation services have become popular and can be installed on mobile phones to provide route information, location of points of interest and user’s current location. LBS has continued to face challenges which include “communication” process towards user reference. Location Based Service System conveys suitable information through a mobile device for effective decision making and reaction within a given time span. This research was geared at understanding the state of LBS technology acceptance and adoption by users in Nairobi Kenya. To do this a quantitative study was carried out through a questionnaire, to investigate mobile phone users’ response on awareness and use of LBS technology. Testing the growth of this technology in this region compared to predictions in previous studies using Technology Acceptance Model (TAM), it is evident that many users may be aware of GPS functionality in mobile phones but are certainly yet to fully embrace the technology as they rarely use it. This points to some underlying challenges towards this technology within this part of the World, thereby recommending for deliberate monitoring and evaluation of LBS technology for sustenance growth based on user satisfaction and acceptance for improved usability.展开更多
文摘The conventional mono-station passive location techniques of direction finding are low in speed and accuracy, due to the little information available. In this paper, a novel measurement-rate (derivative) of phase difference from a two-element antenna array (interferometer) is introduced, accuracy of a passive location system with this measurement and directions of arrival (DOA) is analyzed, and the Cramer-Rao bound of location error of this system for 3D location is examined by simulations.
基金supported by the National Natural Science Foundation of China (Grant No. 11071282)the Chinese Program for New Century Excellent Talents in University (Grant No. NCET-08-06867)+4 种基金the Natural Science Foundation of Hunan Province of China(Grant No. 10JJ7001)the Lotus Scholars Program of Hunan Province of Chinathe Aid Program for Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Province of Chinathe Australian Research Council (GrantNo. DP0559807)the Postgraduate Research and Innovation Project of Hunan Province of China (Grant No. CX2010B243)
文摘Apoptosis proteins play an important role in the development and homeostasis of an organism. The elucidation of the subcellular locations and functions of these proteins is helpful for understanding the mechanism of programmed cell death. In this paper, the recurrent quantification analysis, Hilbert-Huang transform methods, the maximum relevance and minimum redundancy method and support vector machine are used to predict the subcellular location of apoptosis proteins. The validation of the jackknife test suggests that the proposed method can improve the prediction accuracy of the subcellular location of apoptosis proteins and its application may be promising in other fields.
文摘Many products always operate under various complex environment conditions. To describe the dynamic influence of environment factors on their reliability, a method of reliability sensitivity analysis is proposed. In this method, the location parameter is assumed as a function of relevant environment variables while the scale parameter is assumed as an unknown positive constant. Then, the location parameter function is constructed by using the method of radial basis function. Using the varied environment test data, the log-likelihood function is transformed to a generalized linear expression by describing the indicator as Poisson variable. With the generalized linear model, the maximum likelihood estimations of the model coefficients are obtained. With the reliability model, the reliability sensitivity is obtained. An instance analysis shows that the method is feasible to analyze the dynamic variety characters of reliability along with environment factors and is straightforward for engineering application.
基金Supported by the National Natural Science Foundation of China(40871061)
文摘According to the statistical data in the years 2004-2008, both Shift-Share Analysis and Location Quotient Analysis are used to compare the economic development status of counties (districts) in Dingxi City in the years 2004 and 2008. Advantages and disadvantages of industrial structure and competitiveness are analyzed, as well as the impacts of existing industrial structure on economic growth. Development direction and development focus of primary, secondary and tertiary industries are found out. Countermeasures for accelerating the economic development of counties (districts) in Dingxi City are put forward, such as increasing the inputs in characteristic agriculture, promoting the development of primary industry, speeding up the construction of large and medium industrial enterprises, enhancing the development of secondary industry, strengthening comprehensive environmental improvement in tourist area, and actively developing tertiary industry.
文摘The application of geospatial analysis is a need to respond to the increasing number of social conflicts caused by the existence of public places of worships (PPW) in Indonesia. This conflict eventually becomes endemic among Indonesian cross-cultural society. Even though the government has produced a regulation-like policy namely SKB 2006 to manage the establishment of PPW, its contribution to avoiding or reducing the conflicts is in question. Researchers notice that the policy is misused in some incidents to even trigger the conflict. It is due to the presence of people participation defined in SKB 2006 particularly to determine the legalization of PPW. Currently there is no exact foundation used by the government to precisely measure the status of PPW, hence the decision to permit or reject any proposal to establish PPW is determined by the acceptance of surrounding society which in many occasions becomes the cause of the conflict. Therefore the government needs to regain control over the existence of PPW since these types of buildings are public facilities used by people in cross-cultural society. The research is to provide accurate information regarding the existence of PPW and the impact of their presence using geospatial analysis. The objective is to analyze the interaction between PPW and its surrounding objects. The analysis is based on PPW coverage, overlapping and blank spot area. A case study has been conducted to analyze the existence of PPW at Cemorokandang village, a part of Malang city in the province of East Java. The application highlights the issue of overwhelming PPW in the location of analysis.
文摘In the process of rapid industrialization and urbanization,the phenomenon of migrant workers’return accompanied its flow is attracting more and more attention of scholars.Based on the sampling data of 529 migrant workers’return questionnaires,statistical analysis and binary logistic model were used to analyze the return location choice and influencing factors of migrant workers.The study found that the village,the local township and the local county seat are the main choices for the inter-provincial migrant workers of return location.The local township and the local county seat are also the preferred locations for migrant workers to return to business,while in the city and other city are less migrant workers.The main mechanism for the choice of migrant workers of return location is the balance between the family and the economic benefits.The main factors affecting the choice of rural migrant workers’return location are the age of migrant workers,the number of primary and secondary school students,the number of migrant workers,and the per capita cultivated area.The mobility and return of migrant workers are actually the location choices and changes of migrant workers in geospatial space,which depends on the sticky size of different locations.
文摘Due to the problem complexity, simultaneous solution methods are limited. A hybrid algorithm is emphatically proposed for LRP. First, the customers are classified by clustering analysis with preference-fitting rules. Second, a chaos search (CS) algorithm for the optimal routes of LRP scheduling is presented in this paper. For the ergodicity and randomness of chaotic sequence, this CS architecture makes it possible to search the solution space easily, thus producing optimal solutions without local optimization. A case study using computer simulation showed that the CS system is simple and effective, which achieves significant improvement compared to a recent LRP with nonlinear constrained optimization solution. Lastly the pratical anlysis is presented relationship with regional logistics and its development in Fujian province.
文摘Ozonolysis products of four lepidopteral pheromone were identified by methane CI-MS.The spectra obtained were notably simpler than those of EI-MS,the peak of molecular ion was normally close to the base peak,and the characteristic fragment ions were high in m/z,thereby the interpretation was facilitated.
文摘The location of the distribution facilities and the routing of the vehicles from these facilities are interdependent in many distribution systems. Such a concept recognizes the interdependence;attempts to integrate these two decisions have been limited. Multi-objective location-routing problem (MLRP) is combined with the facility location and the vehicle routing decision and satisfied the different objectives. Due to the problem complexity, simultaneous solution methods are limited, which are given in different objectives with conflicts in functions satisfied. Two kinds of optimal mathematical models are proposed for the solution of MLRP. Three methods have been emphatically developed for MLRP. MGA architecture makes it possible to search the solution space efficiently, which provides a path for searching the solution with two-objective LRP. At last the practical proof is given by random analysis for regional distribution with nine cities.
基金Supported by the National High Technology Research and Development Program of China(No.2009AAJ116,2009AAJ208,2010AA7010422)the National Science Foundation for Post-Doctoral Scientists of China(No.20080431379,200902671)the Hubei Natural Science Foundation(No.2009CDB031)
文摘To solve the problem of multiple moving sources passive location,a novel blind source separation(BSS) algorithm based on the multiset canonical correlation analysis(MCCA) is presented by exploiting the different temporal structure of uncorrelated source signals first,and then on the basis of this algorithm,a novel multiple moving sources passive location method is proposed using time difference of arrival(TDOA) and frequency difference of arrival(FDOA) measurements.The key technique of this location method is TDOA and FDOA joint estimation,which is based on BSS.By blindly separating mixed signals from multiple moving sources,the multiple sources location problem can be translated to each source location in turn,and the effect of interference and noise can also be removed.The simulation results illustrate that the performance of the MCCA algorithm is very good with relatively light computation burden,and the location algorithm is relatively simple and effective.
基金supported by the National Natural Science Foundation of China(6107210761271300)+4 种基金the Shaanxi Industry Surmount Foundation(2012K06-12)the Arm and Equipment Pre-research Foundationthe Fundamental Research Funds for the Central Universities of China(K0551302006K5051202045K50511020024)
文摘For the joint time difference of arrival(TDOA) and angle of arrival(AOA) location scene,two methods are proposed based on the rectangular coordinates and the polar coordinates,respectively.The problem is solved perfectly by calculating the target position with the joint TDOA and AOA location.On the condition of rectangular coordinates,first of all,it figures out the radial range between target and reference stations,then calculates the location of the target.In the case of polar coordinates,first of all,it figures out the azimuth between target and reference stations,then figures out the radial range between target and reference stations,finally obtains the location of the target.Simultaneously,simulation analyses show that the theoretical analysis is correct,and the proposed methods also provide the application of the joint TDOA and AOA location algorithm with the theoretical basis.
基金supported by the National Natural Science Foundation of China (Grant NO. 31171515)the Tianjin Natural Science Foundation of China (Grant NO. 11JCZDJC17900)the Knowledge Innovation and Training Program of Tianjin, Tianjin Municipal Education Commission, China (Grant NO. 2013-1-2015 -12)
文摘Homeobox transcription factors participate in the growth and development of plants by regulating cell differentiation, morphogenesis and environmental signal response. To reveal the functions of these transcription factors in rice, we constructed the RNAi vectors of OsHox9, a member of homeobox family, and analyzed the function of OsHox9 using reverse genetics. The plant height and tillering number of RNAi transgenic plants decreased compared with those of wild-type plants. Reverse transcdption-polymerase chain reaction analysis showed that OsHox9 expression reduced in the transgenic plants with phenotypic variance, whereas that in the transgenic plants without phenotypic variance was similar to that in the wild-type plants. This result suggests that the phenotypes of the transgenic plants were caused by RNAi effects. The tissue-specificity of OsHox9 expression indicated that it was expressed in different organs, with high expression in stem apical medstem and young panicles. Subcellular location of OsHox9 demonstrated that it was localized on the cell membrane.
基金Under the auspices of National Natural Science Foundation of China(No.51478007,51178016)Project of Fundamental Research of Chinese Cultural Heritage Research Institute(No.2016-JBKY-08)
文摘The location pattern of different commercial stores in Shichahai, a historic conservation area in Beijing, was investigated from a street centrality perspective. Many previous studies have investigated the relationship between street centrality and land use patterns or commercial activities at interurban or intraurban scales. We considered Shichahai in this study to determine if street centrality applied at the street scale and if the street network was the only factor influencing the selection of store location. First, the nearest neighbor index, nearest neighbor hierarchical spatial cluster(NNHSC), and kernel density estimation(KDE) methods were used to provide baseline spatial distributions of commercial stores. Second, urban network analysis(UNA) tools were used to measure the street centrality indices under two conditions, with and without the weighting of cultural relics calculated by a principal component analysis(PCA). Finally, both store locations and centrality values at nodes were transformed to one unit(raster pixel) for a correlation analysis.The results showed that three of the four store types were clustered and had their own hotspots that were mostly located in the eastern and central parts of city blocks. The most momentous findings were determined from the street centrality indices. Among the three store types with correlation coefficients above 0.5, all centrality indices with landmark weighting, except straightness, had higher correlations,with closeness with landmark weighting having the highest correlation, followed by betweenness with landmark weighting. Therefore,we statistically concluded that street centrality could apply at the street scale and that the street network was not the only factor that influenced store location pattern, with landmarks also playing a significant role. The results provide guidance in determining the selection strategy for stores in a historic conservation area.
基金Supported by National Natural Science Foundation of China(Grant Nos.51575176,51375162)Scientific Research Foundation of Hunan Provincial Education Department of China(Grant No.15B085)Postgraduate Innovation Foundation of Hunan University of Science and Technology,China(Grant No.S140020)
文摘For the high-speed gasoline engine turbocharger rotor, due to the heterogeneity of multiple parts material, manufacturing and assembly errors, running wear in impeller and uneven carbon of turbine, the random unbalance usually can be developed which will induce excessive rotor vibration, and even lead to nonlinear vibration accidents. However, the investigation of unbalance location on the nonlinear high-speed turbocharger rotordynamic characteristics is less. In order to discuss the rotor unbalance location effects of turbocharger with nonlinear floating ring bearings(FRBs), the realistic turbocharger of gasoline engine is taken as a research object. The rotordynamic equations of motion under the condition of unbalance are derived by applied unbalance force and nonlinear oil film force of FRBs. The FE model of turbocharger rotor-bearing system is modeled which includes the unbalance excitation and nonlinear FRBs. Under the conditions of four different applied locations of unbalance, the nonlinear transient analyses are performed based on the rotor FEM. The differences of dynamic behavior are obvious to the turbocharger rotor systems for four conditions, and the bifurcation phenomena are different. From the results of waterfall and transient response analysis, the speed for the appearance of fractional frequency is not identical and the amplitude magnitude is different from the different unbalance locations, and the non-synchronous vibration does not occur in the turbocharger and the amplitude is relative stable and minimum under the condition 4. The turbocharger vibration and non-synchronous components could be reduced or suppressed by controlling the applied location of unbalance, which is helpful for the dynamic design, fault diagnosis and vibration control of the high-speed gasoline engine turbochargers.
基金National High Technology Research and Development Program of China(2003AA212030).
文摘Grain size, determined chiefly by grain length, is one of the main factors affecting the grain yield in rice production. To study the trait of rice grain size, F1 and F2 populations were developed from crosses Shuhui 881/Y34 and Shuhui 527/Y34, and genetic analysis for minute grain was performed. The F1 populations showed minute grains, and grain size segregations in the two F2 populations were both in accordance with the ratio of 3:1, indicating that minute grain in Y34 was controlled by a completely dominant gene. By using the F2 population from Shuhui 881/Y34, this dominant gene, tentatively designated as Mi3(t), was mapped based on SSR markers in the interval between RM282 (genetic distance of 5.1 cM) and RM6283 (genetic distance of 0.9 cM) on the short arm of chromosome 3.
基金This study was funded by the National Natural Science Foundation of China(No.81673273 and No.30600511).
文摘Summary:Several studies have indicated that stroke survivors with multiple lesions or with larger lesion volumes have a higher risk of stroke recurrence.However,the relationship between lesion locations and stroke recurrence is unclear.We conducted a prospective cohort study of first-ever ischemic stroke survivors who were consecutively enrolled from January 2010 to December 2015.Stroke recurrence was assessed every 3 months after post-discharge via telephone interviews by trained interviewers.Lesion locations were obtained from hospital-based MRI or CT scans and classified using two classification systems that were based on cerebral hemisphere or vascular territory and brain anatomical structures.Flexible parametric survival models using the proportional hazards scale(PH model)were used to analyze the time-to-event data.Among 633 survivors,63.51%(n-402)had anterior circulation ischemia(ACI),and morc than half of all ACIs occurred in the subcortex.After a median follow-up of 2.5 years,117(18.48%)survivors developed a recurrent stroke.The results of the multivariate PH model showed that survivors with non-brain lesions were at higher risk of recurrence than those with right-side lesions(HR,2.79;95%CI,1.53,5.08;P-0.001).There was no increase in risk among survivors with left-side lesions(HR,0.97;95%CI,0.53,1.75;P=0.914)or both-side lesions(HR,1.24;95%CI,0.75,2.07;P-0.401)compared to those with right-side lesions.Additionally,there were no associations between stroke ecurrence and lesion locations that were classified based on vascular territory and brain anatomical structures.It was concluded that first-ever ischemic stroke survivors with non-brain lesion had higher recurrence risk than those with right-side lesion,although no significant associations were found when the lesion locations were classified by vascular territory and brain anatomical structures.
文摘Location Based Navigation System (LBNS) is a specific Location Based Service (LBS) purely for navigational purpose. These systems resolve position of a user by using GNSS/GPS positioning technologies, to which supplementary information on goods and services are tagged. The navigation services have become popular and can be installed on mobile phones to provide route information, location of points of interest and user’s current location. LBS has continued to face challenges which include “communication” process towards user reference. Location Based Service System conveys suitable information through a mobile device for effective decision making and reaction within a given time span. This research was geared at understanding the state of LBS technology acceptance and adoption by users in Nairobi Kenya. To do this a quantitative study was carried out through a questionnaire, to investigate mobile phone users’ response on awareness and use of LBS technology. Testing the growth of this technology in this region compared to predictions in previous studies using Technology Acceptance Model (TAM), it is evident that many users may be aware of GPS functionality in mobile phones but are certainly yet to fully embrace the technology as they rarely use it. This points to some underlying challenges towards this technology within this part of the World, thereby recommending for deliberate monitoring and evaluation of LBS technology for sustenance growth based on user satisfaction and acceptance for improved usability.