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1.
Materials (Basel) ; 16(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37445047

RESUMO

Safety of the observation window is one of the core concerns for manned submersibles. When subjected to underwater static pressure, extrusion and creep deformation always occur in the observation window, which can pose a threat to both safety and optical performance. To assess the deformation, real-time and non-contact monitoring methods are necessary. In this study, a conceptual setup based on the waveplate rotation and dual-DoFP (division of focal-plane polarimeter) polarization camera is built for the observation window's creep monitoring by measuring the Mueller matrix images of the samples under different pressures and durations. Then, a series of characteristic parameters, such as t1, R, r, R', are extracted from the Muller matrix images by Mueller matrix transformation (MMT), Mueller matrix polar decomposition (MMPD), correlation analysis and phase unwrapping method. The results demonstrate that these parameters can effectively describe the observation window's creep at different pressure levels which are simulated by finite element analysis. Additionally, more characterization parameters, such as ψ, A and D, are given from the Mueller matrix images and discussed to illustrate the method's potential for further applications and investigations. Ultimately, future devices based on this method could serve as a valuable tool for real-time and non-contact creep monitoring of the submersible observation windows.

2.
Rev Sci Instrum ; 94(1): 014504, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36725612

RESUMO

A decoupling method is proposed for micro-Newton thrust measurement with a torsion pendulum. The basic approach is to reduce the influences introduced by the propellant tube and wires of the thruster. A hollow aluminum tube is used to hang the torsion pendulum and is also chosen as the transport pipe for the propellant of the thruster. The electric control box of the thruster is mounted on the pendulum body, which is powered by an externally installed power supply through a liquid metal conductive unit. The control of the electric control box is performed through wireless transmission. With this design, the influences of the propellant tube and connection wires between the torsion pendulum and the outside device are reduced and the stability of the torsion spring constant of the system can be improved. The use of the liquid metal conductive unit reduces the coupling between the wires and the measurement system. The feasibility of the wireless transmission is analyzed. The error sources during the thrust measurement are analyzed, and the expected three σ uncertainty of the thrust is 0.032+(0.10%*F)2µN for the measurement of the cold gas thruster. The scheme provides a thrust measurement with higher precision and stability.

3.
Micromachines (Basel) ; 13(12)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36557423

RESUMO

The moving-base gravimeter is one of the key instruments used for Earth gravity survey. The accuracy of the survey data is closely related to the calibration precision of several key parameters, such as the damping delay time, the drift coefficient, the gravity scale factor, and the measurement accuracy. This paper will introduce the development of the CHZ-II gravimeter system in which a cylindrical sampling mass suspended vertically by a zero-length spring acts as a sensitive probe to measure specific force. Meanwhile, a GNSS (Global Navigation Satellite System) positioning system is employed to monitor the carrier motion and to remove the inertia acceleration. In order to achieve high-precision calibrations for the key parameters, a new calibration method performed along forward and reverse overlapping lines is proposed, which is used to calibrate the above parameters and to estimate the measurement accuracy of the instrument used for a normal gravity survey. The calibration principle and the shipboard calibration data processing method are introduced. The calibration was performed for three moving-base gravimeters and the corresponding results are determined, indicating that the method can significantly improve the accuracy of the parameters. For the CHZ-II gravimeter, the measurement accuracy of the survey is 0.471 mGal (1 mGal = 10-5 m/s2), which improved by 19.5% after applying the calibrated parameters. This method is also practical for use with aviation, marine and even vehicle-carried moving-base gravimeters.

4.
Sensors (Basel) ; 22(6)2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35336453

RESUMO

Stress detection of the conical frustum window is a very important issue to ensure the safety of deep manned submersibles. In this paper, we propose a method based on polarization imaging to evaluate the stress accumulation and recovery in the conical frustum window. An experimental setup of Mueller matrix polarimetry is built, and the samples are made by referring to the typical conical frustum windows in submersibles. By pressurizing different pressures on the samples, we can find the changes of their Mueller matrix images and further derived polarization parameters. The results show that the polarization parameters can characterize the stress transfer process and the elastic-plastic transformation process of the window under different pressurization pressures. We also use a two-layered wave plate model to simulate the stress distribution in the window, which reveals different performances of the former and latter layers of the window under pressurization. Finally, we use a finite element model to simulate and understand some of the above experimental results. This proposed method is expected to provide new possibilities for monitoring the window stress and further ensure the safety of deep manned submersibles.


Assuntos
Diagnóstico por Imagem , Refração Ocular , Análise Espectral
5.
IEEE/ACM Trans Comput Biol Bioinform ; 15(6): 1943-1950, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28320675

RESUMO

Swarm robots search for multiple targets in collaboration in unknown environments has been addressed in this paper. An improved grouping strategy based on constriction factors Particle Swarm Optimization is proposed. Robots are grouped under this strategy after several iterations of stochastic movements, which considers the influence range of targets and environmental information they have sensed. The group structure may change dynamically and each group focuses on searching one target. All targets are supposed to be found finally. Obstacle avoidance is considered during the search process. Simulation compared with previous method demonstrates the adaptability, accuracy, and efficiency of the proposed strategy in multiple targets searching.


Assuntos
Algoritmos , Inteligência Artificial , Biologia Computacional/métodos , Robótica/métodos , Simulação por Computador
6.
Sensors (Basel) ; 17(9)2017 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-28832538

RESUMO

High-precision electrostatic accelerometers have achieved remarkable success in satellite Earth gravity field recovery missions. Ultralow-noise inertial sensors play important roles in space gravitational wave detection missions such as the Laser Interferometer Space Antenna (LISA) mission, and key technologies have been verified in the LISA Pathfinder mission. Meanwhile, at Huazhong University of Science and Technology (HUST, China), a space accelerometer and inertial sensor based on capacitive sensors and the electrostatic control technique have also been studied and developed independently for more than 16 years. In this paper, we review the operational principle, application, and requirements of the electrostatic accelerometer and inertial sensor in different space missions. The development and progress of a space electrostatic accelerometer at HUST, including ground investigation and space verification are presented.

7.
Bioinformatics ; 30(6): 823-30, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24192543

RESUMO

MOTIVATION: Limited cohort of transcription factors is capable to structure various gene-expression patterns. Transcriptional cooperativity (TC) is deemed to be the main mechanism of complexity and precision in regulatory programs. Although many data types generated from numerous experimental technologies are utilized in an attempt to understand combinational transcriptional regulation, complementary computational approach that can integrate diverse data resources and assimilate them into biological model is still under development. RESULTS: We developed a novel Bayesian approach for integrative analysis of proteomic, transcriptomic and genomic data to identify specific TC. The model evaluation demonstrated distinguishable power of features derived from distinct data sources and their essentiality to model performance. Our model outperformed other classifiers and alternative methods. The application that contextualized TC within hepatocarcinogenesis revealed carcinoma associated alterations. Derived TC networks were highly significant in capturing validated cooperativity as well as revealing novel ones. Our methodology is the first multiple data integration approach to predict dynamic nature of TC. It is promising in identifying tissue- or disease-specific TC and can further facilitate the interpretation of underlying mechanisms for various physiological conditions. CONTACT: tieliushi01@gmail.com SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Redes Reguladoras de Genes , Genômica/métodos , Teorema de Bayes , Transformação Celular Neoplásica , Expressão Gênica , Genoma Humano , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
8.
PLoS One ; 8(7): e65958, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23843948

RESUMO

INTRODUCTION: The aim of this study was to examine health-related quality of life (HRQoL) as measured by EQ-5D and to investigate the influence of chronic conditions and other risk factors on HRQoL based on a distributed sample located in Shaanxi Province, China. METHODS: A multi-stage stratified cluster sampling method was performed to select subjects. EQ-5D was employed to measure the HRQoL. The likelihood that individuals with selected chronic diseases would report any problem in the EQ-5D dimensions was calculated and tested relative to that of each of the two reference groups. Multivariable linear regression models were used to investigate factors associated with EQ VAS. RESULTS: The most frequently reported problems involved pain/discomfort (8.8%) and anxiety/depression (7.6%). Nearly half of the respondents who reported problems in any of the five dimensions were chronic patients. Higher EQ VAS scores were associated with the male gender, higher level of education, employment, younger age, an urban area of residence, access to free medical service and higher levels of physical activity. Except for anemia, all the selected chronic diseases were indicative of a negative EQ VAS score. The three leading risk factors were cerebrovascular disease, cancer and mental disease. Increases in age, number of chronic conditions and frequency of physical activity were found to have a gradient effect. CONCLUSION: The results of the present work add to the volume of knowledge regarding population health status in this area, apart from the known health status using mortality and morbidity data. Medical, policy, social and individual attention should be given to the management of chronic diseases and improvement of HRQoL. Longitudinal studies must be performed to monitor changes in HRQoL and to permit evaluation of the outcomes of chronic disease intervention programs.


Assuntos
Ansiedade/psicologia , Transtornos Cerebrovasculares/psicologia , Dor Crônica/psicologia , Depressão/psicologia , Neoplasias/psicologia , Qualidade de Vida/psicologia , Adulto , Idoso , Ansiedade/epidemiologia , Ansiedade/fisiopatologia , Transtornos Cerebrovasculares/epidemiologia , Transtornos Cerebrovasculares/fisiopatologia , China/epidemiologia , Dor Crônica/epidemiologia , Dor Crônica/fisiopatologia , Depressão/epidemiologia , Depressão/fisiopatologia , Feminino , Nível de Saúde , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Neoplasias/fisiopatologia , Medição da Dor , Fatores de Risco , Inquéritos e Questionários
9.
Protein J ; 32(5): 373-85, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23700221

RESUMO

The similarity comparison of binding sites based on amino acid between different proteins can facilitate protein function identification. However, Binding site usually consists of several crucial amino acids which are frequently dispersed among different regions of a protein and consequently make the comparison of binding sites difficult. In this study, we introduce a new method, named as chemical and geometric similarity of binding site (CGS-BSite), to compute the ligand binding site similarity based on discrete amino acids with maximum-weight bipartite matching algorithm. The principle of computing the similarity is to find a Euclidean Transformation which makes the similar amino acids approximate to each other in a geometry space, and vice versa. CGS-BSite permits site and ligand flexibilities, provides a stable prediction performance on the flexible ligand binding sites. Binding site prediction on three test datasets with CGS-BSite method has similar performance to Patch-Surfer method but outperforms other five tested methods, reaching to 0.80, 0.71 and 0.85 based on the area under the receiver operating characteristic curve, respectively. It performs a marginally better than Patch-Surfer on the binding sites with small volume and higher hydrophobicity, and presents good robustness to the variance of the volume and hydrophobicity of ligand binding sites. Overall, our method provides an alternative approach to compute the ligand binding site similarity and predict potential special ligand binding sites from the existing ligand targets based on the target similarity.


Assuntos
Biologia Computacional/métodos , Proteínas/química , Algoritmos , Sítios de Ligação , Bases de Dados de Proteínas , Ligantes , Ligação Proteica , Proteínas/metabolismo
10.
J Med Syst ; 36(2): 723-36, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20703657

RESUMO

This article aims at building clinical data groups for Electronic Medical Records (EMR) in China. These data groups can be reused as basic information units in building the medical sheets of Electronic Medical Record Systems (EMRS) and serve as part of its implementation guideline. The results were based on medical sheets, the forms that are used in hospitals, which were collected from hospitals. To categorize the information in these sheets into data groups, we adopted the Health Level 7 Clinical Document Architecture Release 2 Model (HL7 CDA R2 Model). The regulations and legal documents concerning health informatics and related standards in China were implemented. A set of 75 data groups with 452 data elements was created. These data elements were atomic items that comprised the data groups. Medical sheet items contained clinical records information and could be described by standard data elements that exist in current health document protocols. These data groups match different units of the CDA model. Twelve data groups with 87 standardized data elements described EMR headers, and 63 data groups with 405 standardized data elements constituted the body. The later 63 data groups in fact formed the sections of the model. The data groups had two levels. Those at the first level contained both the second level data groups and the standardized data elements. The data groups were basically reusable information units that served as guidelines for building EMRS and that were used to rebuild a medical sheet and serve as templates for the clinical records. As a pilot study of health information standards in China, the development of EMR data groups combined international standards with Chinese national regulations and standards, and this was the most critical part of the research. The original medical sheets from hospitals contain first hand medical information, and some of their items reveal the data types characteristic of the Chinese socialist national health system. It is possible and critical to localize and stabilize the adopted international health standards through abstracting and categorizing those items for future sharing and for the implementation of EMRS in China.


Assuntos
Coleta de Dados/métodos , Registros Eletrônicos de Saúde/organização & administração , Administração Hospitalar/métodos , Sistemas de Informação/organização & administração , China , Coleta de Dados/normas , Coleta de Dados/estatística & dados numéricos , Registros Eletrônicos de Saúde/normas , Registros Eletrônicos de Saúde/estatística & dados numéricos , Administração Hospitalar/normas , Administração Hospitalar/estatística & dados numéricos , Humanos , Sistemas de Informação/normas , Sistemas de Informação/estatística & dados numéricos , Integração de Sistemas
11.
BMC Health Serv Res ; 11: 318, 2011 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-22108389

RESUMO

BACKGROUND: Long waiting times for registration to see a doctor is problematic in China, especially in tertiary hospitals. To address this issue, a web-based appointment system was developed for the Xijing hospital. The aim of this study was to investigate the efficacy of the web-based appointment system in the registration service for outpatients. METHODS: Data from the web-based appointment system in Xijing hospital from January to December 2010 were collected using a stratified random sampling method, from which participants were randomly selected for a telephone interview asking for detailed information on using the system. Patients who registered through registration windows were randomly selected as a comparison group, and completed a questionnaire on-site. RESULTS: A total of 5641 patients using the online booking service were available for data analysis. Of them, 500 were randomly selected, and 369 (73.8%) completed a telephone interview. Of the 500 patients using the usual queuing method who were randomly selected for inclusion in the study, responses were obtained from 463, a response rate of 92.6%. Between the two registration methods, there were significant differences in age, degree of satisfaction, and total waiting time (P<0.001). However, gender, urban residence, and valid waiting time showed no significant differences (P>0.05). Being ignorant of online registration, not trusting the internet, and a lack of ability to use a computer were three main reasons given for not using the web-based appointment system. The overall proportion of non-attendance was 14.4% for those using the web-based appointment system, and the non-attendance rate was significantly different among different hospital departments, day of the week, and time of the day (P<0.001). CONCLUSION: Compared to the usual queuing method, the web-based appointment system could significantly increase patient's satisfaction with registration and reduce total waiting time effectively. However, further improvements are needed for broad use of the system.


Assuntos
Assistência Ambulatorial/organização & administração , Agendamento de Consultas , Internet/estatística & dados numéricos , Adulto , Atitude Frente aos Computadores , China , Feminino , Pesquisa sobre Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente/estatística & dados numéricos , Pesquisa Qualitativa , Estudos Retrospectivos , Fatores de Tempo , Listas de Espera
12.
Healthc Inform Res ; 17(4): 205-13, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22259722

RESUMO

OBJECTIVES: This study is aimed at developing a set of data groups (DGs) to be employed as reusable building blocks for the construction of the eight most common clinical documents used in China's general hospitals in order to achieve their structural and semantic standardization. METHODS: The Diagnostics knowledge framework, the related approaches taken from the Health Level Seven (HL7), the Integrating the Healthcare Enterprise (IHE), and the Healthcare Information Technology Standards Panel (HITSP) and 1,487 original clinical records were considered together to form the DG architecture and data sets. The internal structure, content, and semantics of each DG were then defined by mapping each DG data set to a corresponding Clinical Document Architecture data element and matching each DG data set to the metadata in the Chinese National Health Data Dictionary. By using the DGs as reusable building blocks, standardized structures and semantics regarding the clinical documents for semantic interoperability were able to be constructed. RESULTS: Altogether, 5 header DGs, 48 section DGs, and 17 entry DGs were developed. Several issues regarding the DGs, including their internal structure, identifiers, data set names, definitions, length and format, data types, and value sets, were further defined. Standardized structures and semantics regarding the eight clinical documents were structured by the DGs. CONCLUSIONS: This approach of constructing clinical document standards using DGs is a feasible standard-driven solution useful in preparing documents possessing semantic interoperability among the disparate information systems in China. These standards need to be validated and refined through further study.

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