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An internal ballistic model of electromagnetic railgun based on PFN coupled with multi-physical field and experimental validation
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作者 Benfeng Gu Haiyuan Li Baoming Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期254-261,共8页
To accelerate the practicality of electromagnetic railguns,it is necessary to use a combination of threedimensional numerical simulation and experiments to study the mechanism of bore damage.In this paper,a three-dime... To accelerate the practicality of electromagnetic railguns,it is necessary to use a combination of threedimensional numerical simulation and experiments to study the mechanism of bore damage.In this paper,a three-dimensional numerical model of the augmented railgun with four parallel unconventional rails is introduced to simulate the internal ballistic process and realize the multi-physics field coupling calculation of the rail gun,and a test experiment of a medium-caliber electromagnetic launcher powered by pulse formation network(PFN)is carried out.Various test methods such as spectrometer,fiber grating and high-speed camera are used to test several parameters such as muzzle initial velocity,transient magnetic field strength and stress-strain of rail.Combining the simulation results and experimental data,the damage condition of the contact surface is analyzed. 展开更多
关键词 Internal ballistic modeling Electromagnetic rail gun Multi-physics field coupling Experimental validation PFN
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Adaptive Robust Servo Control for Vertical Electric Stabilization System of Tank and Experimental Validation
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作者 Darui Lin Xiuye Wang +1 位作者 Yimin Wang Guolai Yang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期326-342,共17页
A tracking stability control problem for the vertical electric stabilization system of moving tank based on adaptive robust servo control is addressed.This paper mainly focuses on two types of possibly fast timevaryin... A tracking stability control problem for the vertical electric stabilization system of moving tank based on adaptive robust servo control is addressed.This paper mainly focuses on two types of possibly fast timevarying but bounded uncertainty within the vertical electric stabilization system:model parameter uncertainty and uncertain nonlinearity.First,the vertical electric stabilization system is constructed as an uncertain nonlinear dynamic system that can reflect the practical mechanics transfer process of the system.Second,the dynamical equation in the form of state space is established by designing the angular tracking error.Third,the comprehensive parameter of system uncertainty is designed to estimate the most conservative effects of uncertainty.Finally,an adaptive robust servo control which can effectively handle the combined effects of complex nonlinearity and uncertainty is proposed.The feasibility of the proposed control strategy under the practical physical condition is validated through the tests on the experimental platform.This paper pioneers the introduction of the internal nonlinearity and uncertainty of the vertical electric stabilization system into the settlement of the tracking stability control problem,and validates the advanced servo control strategy through experiment for the first time. 展开更多
关键词 Adaptive robust servo control Experimental validation Nonlinearity compensation System uncertainty Vertical electric stabilization system
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Method Development and Validation of the Simultaneous Analysis of Methylisothiazolinone, Methylchloroisothiazolinone, Benzisothiazolinone and Bronopol in Washing-Up Liquid
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作者 Etienne Jooken Ruis Amery Boudewijn Meesschaert 《American Journal of Analytical Chemistry》 CAS 2024年第1期43-55,共13页
A method of analysis for the simultaneous determination of methylisothiazolinone (MI), methylchloroisothiazolinone (CMI), benzisothiazolinone (BIT) and Bronopol (BNP) in washing-up liquid was established. The method c... A method of analysis for the simultaneous determination of methylisothiazolinone (MI), methylchloroisothiazolinone (CMI), benzisothiazolinone (BIT) and Bronopol (BNP) in washing-up liquid was established. The method consisted of a gradient HPLC analysis at three different wavelengths. The four compounds could be analyzed with good precision and accuracy. 展开更多
关键词 PRESERVATIVES Analytical validation METHYLISOTHIAZOLINONE Methylchloroisothiazolinone Benzisothiazolinone BRONOPOL HPLC Washing-Up Liquid
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Validity and Reliability of a Mental Health Recovery Checklist for Young Adults
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作者 Brianna Cerrito Jamie Xiao +2 位作者 Amie DiTomasso Amanda Fialk Jocelyn Bolin 《International Journal of Mental Health Promotion》 2024年第4期317-323,共7页
The purpose of the present study is to evaluate the internal consistency and construct validity of a self-report checklist measuring clinical mental health recovery across six key domains:family and relationships,occu... The purpose of the present study is to evaluate the internal consistency and construct validity of a self-report checklist measuring clinical mental health recovery across six key domains:family and relationships,occupation and school,physical health,mental health,spirituality,and social support systems.The Mental Health Recovery Checklist(MHRC)was developed at The Dorm,an intensive outpatient mental health treatment program for young adults in New York,NY,and Washington DC that services individuals between the ages of 18 and 35 years old.The present study is cross-sectional,as data were pulled from clients’records who were discharged between January 2018 and May 2023.Pearson Correlations and Cronbach’s alpha were used to determine scale reliability.To establish validity,an Exploratory Factor Analysis(EFA)was conducted to assess a single-factor model using Principal Axis Factoring.Cronbach’s alpha was high(α=0.88),indicating good reliability.In the EFA,all items loaded strongly on a single factor.The unidimensional structure revealed in the EFA highlights the interconnected nature of various life domains as they pertain to mental health recovery in young adults.Future research is warranted to explore whether there are additional dimensions of mental health recovery that have not been assessed in the present scale. 展开更多
关键词 Mental health recovery young adult validation study mental health checklist
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Towards Lessening Learners’Aversive Emotions and Promoting Their Mental Health:Developing and Validating a Measurement of English Speaking Demotivation in the Chinese EFL Context
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作者 Chili Li Xinxin Zhao +2 位作者 Ziwen Pan Ting Yi Long Qian 《International Journal of Mental Health Promotion》 2024年第2期161-175,共15页
While a plethora of studies has been conducted to explore demotivation and its impact on mental health in second language(L2)education,scanty research focuses on demotivation in L2 speaking learning.Particularly,littl... While a plethora of studies has been conducted to explore demotivation and its impact on mental health in second language(L2)education,scanty research focuses on demotivation in L2 speaking learning.Particularly,little research explores the measures to quantify L2 speaking demotivation.The present two-phase study attempts to develop and validate an English Speaking Demotivation Scale(ESDS).To this end,an independent sample of 207 Chinese tertiary learners of English as a Foreign Language(EFL)participated in the development phase,and another group of 188 Chinese EFL learners was recruited for the validation of the scale.Exploratory Factor Analysis(EFA)and Confirmatory Factor Analysis(CFA)were employed to determine the factor structure of the scale.The EFA results revealed a six-factor solution with Teacher-related Factors in Learning Spoken English(TFLSE),Interest and Valence in Learning Spoken English(IVLSE),Self-efficacy in Learning Spoken English(SELSE),Negative Peer Influence in Learning Spoken English(NPILSE),Undesirable Environment for Learning Spoken English(UELSE),and Negative Influence of Assessment and Learning Materials in speaking class(NIALM).In the validation phase,Confirmatory Factor Analysis(CFA)was performed to validate the internal structure of the scale.The CFA results showed that the model fits the data well.Overall,the ESDS is a robust and trustworthy psychometric tool that could be utilized to examine L2 speaking demotivation.Implications for diminishing EFL learners’demotivation,lessening their aversive emotions and promoting their mental health are also discussed. 展开更多
关键词 Demotivation for learning English speaking ESDS scale development and validation Chinese EFL learners mental health
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Validity,Reliability,and Measurement Invariance of the Thai Smartphone Application-Based Addiction Scale and Bergen Social Media Addiction Scale
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作者 Kamolthip Ruckwongpatr Chirawat Paratthakonkun +8 位作者 Usanut Sangtongdee Iqbal Pramukti Ira Nurmala Kanokwan Angkasith Weena Thanachaisakul Jatuphum Ketchatturat Mark DGriffiths Yi-Kai Kao Chung-Ying Lin 《International Journal of Mental Health Promotion》 2024年第4期293-302,共10页
Background:In recent years,there has been increased research interest in both smartphone addiction and social media addiction as well as the development of psychometric instruments to assess these constructs.However,t... Background:In recent years,there has been increased research interest in both smartphone addiction and social media addiction as well as the development of psychometric instruments to assess these constructs.However,there is a lack of psychometric evaluation for instruments assessing smartphone addiction and social media addiction in Thailand.The present study evaluated the psychometric properties and gender measurement invariance of the Thai version of the Smartphone Application-Based Addiction Scale(SABAS)and Bergen Social Media Addiction Scale(BSMAS).Method:A total of 801 Thai university students participated in an online survey from January 2022 to July 2022 which included demographic information,SABAS,BSMAS,and the Internet Gaming Disorder Scale-Short Form(IGDS9-SF).Results:Confirmatory Factor Analyses(CFAs)found that both the SABAS and BSMAS had a one-factor structure.Findings demonstrated adequate psychometric properties of both instruments and also supported measurement invariance across genders.Moreover,scores on the SABAS and BSMAS were correlated with scores on the IGDS9-SF.Conclusion:The results indicated that the SABAS and BSMAS are useful psychometric instruments for assessing the risk of smartphone addiction and social media addiction among Thai young adults. 展开更多
关键词 Factor analysis smartphone addiction social media addiction smartphone application-based addiction scale bergen social media addiction scale psychometric validation
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Validation of the index for the core competence of nurses leading discharge planning for older patients in China
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作者 Lu Lu Ling Ding +3 位作者 Hong-Yan Lu Xin-Ning Lei Zhen-Zhen Wu Rui Zhang 《Frontiers of Nursing》 2023年第1期51-64,共14页
Objective:With the continuous advancement of aging in China,the number of older inpatients has increased sharply.Older patients have a high demand for planning their discharge services.Nurses serve as the leader of di... Objective:With the continuous advancement of aging in China,the number of older inpatients has increased sharply.Older patients have a high demand for planning their discharge services.Nurses serve as the leader of discharge planning for patients;there is a lack of reliable evaluation tool to evaluate the core competitiveness of nurses who implement discharge planning for older patients in China.The purpose of this study was to validate the index for the core competence of nurses who lead discharge planning for older patients developed by a project team through the Delphi method in the early stage.Methods:A cross-sectional questionnaire survey with 3-stage stratified sampling was used to select 1075 nurses from 17 public general hospitals in Ningxia,China.Results:The index consists of 4 first-level indicators,13 second-level indicators,and 57 third-level indicators.The results show that 57 third-level indicators had good discrimination.With exploratory factor analysis(EFA),4 common factors that explained 72.79%of the total variance were extracted.The Cronbach's a was 0.98,and the retest reliability within a 14-d interval was 0.86.The confirmatory factor analysis(CFA)results show that the fit of the index structure was good.The criterion validity was 0.73.Conclusions:The index presented excellent psychometric proper ties and can be used to measure the core competence of nurses in implementing discharge planning for older patients in China. 展开更多
关键词 core competence discharge planning instrument NURSE older patient RELIABILITY validATION validity
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Solriamfetol impurities:Synthesis,characterization,and analytical method(UPLC-UV)validation
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作者 Nafisah Al-Rifai Anas Alshishani +4 位作者 Fouad Darras Ola Taha Shereen Abu-Jalloud Lena Shaghlil Yousef Al-Ebini 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第4期403-411,共9页
Given that impurities may affect the quality and safety of drug products,impurity identification and profiling is an integral part of drug quality control and is particularly important for newly developed medications ... Given that impurities may affect the quality and safety of drug products,impurity identification and profiling is an integral part of drug quality control and is particularly important for newly developed medications such as solriamfetol,which is used to treat excessive daytime sleepiness.Although the highperformance liquid chromatography analysis of commercial solriamfetol has revealed the presence of several impurities,their synthesis,structure elucidation,and chromatographic determination have not been reported yet.To bridge this gap,we herein identified,synthesized,and isolated eight processrelated solriamfetol impurities,characterized them using spectroscopic and chromatographic techniques,and proposed plausible mechanisms of their formation.Moreover,we developed and validated a prompt impurity analysis method based on ultrahigh-performance liquid chromatography with UV detection,revealing that its selectivity,linearity,accuracy,precision,and quantitation limit meet the acceptance criteria of method validation stipulated by the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use.Thus,the developed method was concluded to be suitable for the routine analysis of solriamfetol substances. 展开更多
关键词 Solriamfetol Impurity analysis Impurity synthesis UPLC Method validation
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Prediction of ground-borne vibration induced by impact pile driving:numerical approach and experimental validation
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作者 A.Colaço P.Alves Costa +2 位作者 C.Ferreira C.Parente J.Fernandez-Ruiz 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第4期921-935,共15页
Deep foundations are currently used in engineering practice to solve problems caused by weak geotechnical characteristics of the ground.Impact pile driving is an interesting and viable solution from economic and techn... Deep foundations are currently used in engineering practice to solve problems caused by weak geotechnical characteristics of the ground.Impact pile driving is an interesting and viable solution from economic and technical points of view.However,it is necessary to ensure that the environmental drawbacks,namely ground-borne vibration,are adequately met.For this purpose,the authors propose an axisymmetric finite element method-perfectly matched layer(FEM-PML)approach,where the nonlinear behavior of the soil is addressed through an equivalent linear methodology.Given the complexity of the problem,an experimental test site was developed and fully characterized.The experimental work comprised in-situ and laboratory soil characterization,as well as the measurement of vibrations induced during pile driving.The comparison between experimental and numerical results demonstrated a very good agreement,from which it can be concluded that the proposed numerical approach is suitable for the prediction of vibrations induced by impact pile driving.The experimental database is available as supplemental data and may be used by other researchers in the validation of their prediction models. 展开更多
关键词 pile driving ground-borne vibrations numerical modeling experimental validation
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Validation and accuracy analysis of wind products from scatterometer onboard the HY-2B satellite
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作者 Sheng Yang Bo Mu +4 位作者 Haoqiang Shi Chaofei Ma Wu Zhou Juhong Zou Mingsen Lin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第2期74-82,共9页
The Chinese marine dynamic environment satellite HY-2B was launched in October 2018 and carries a Ku-band scatterometer.This paper focuses on the accuracies of HY-2B scatterometer wind data during the period from Nove... The Chinese marine dynamic environment satellite HY-2B was launched in October 2018 and carries a Ku-band scatterometer.This paper focuses on the accuracies of HY-2B scatterometer wind data during the period from November 2018 to May 2021.The HY-2B wind data are validated against global moored buoys operated by the U.S.National Data Buoy Center and Tropical Atmosphere Ocean,numerical model data by the National Centers for Environmental Prediction,and the Advanced Scatterometer data issued by the Remote Sensing System.The results showed that the wind speeds and directions observed by the HY-2B scatterometer agree well with these buoy wind measurements.The root-mean-squared errors(RMSEs)of the HY-2B wind speed and direction are 0.74 m/s and 11.74°,respectively.For low wind speeds(less than 5 m/s),the standard deviation of the HY-2B-derived wind direction is higher than 20°,which implies that the HY-2B wind direction for low wind speeds is less accurate than that for moderate to high wind speed ranges.The RMSE of the HY-2B wind speed is slightly larger in high latitude oceans(60°–90°S and 60°–90°N)than in low latitude regions.Furthermore,the dependence of the residuals on the cross-track location of wind vector cells and the stability of the HY-2B scatterometer wind products are discussed.The wind stability assessment results indicate that a clear yearly oscillation is observed for the HY-2B wind speed bias which is due to seasonal weather variations.In general,the accuracy of HY-2B winds meets the operational precision requirement and is consistent with other wind data. 展开更多
关键词 sea surface wind validATION microwave remote sensing SCATTEROMETER
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Analysis and Optimization of Validation Procedure in Blockchain-Enhanced Wireless Resource Sharing and Transactions
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作者 Enyu Du Yang Gao +3 位作者 Wenjun Wu Zhaoxin Yang Yufeng Yin Pengbo Si 《China Communications》 SCIE CSCD 2023年第10期245-261,共17页
To ensure the security of resource and intelligence sharing in 6G,blockchain has been widely adopted in wireless communications and applications.Although blockchain can ensure the traceability and non-tamperability of... To ensure the security of resource and intelligence sharing in 6G,blockchain has been widely adopted in wireless communications and applications.Although blockchain can ensure the traceability and non-tamperability of data in the concatenated blocks,it cannot guarantee the honest behaviors of users in the application before the generation of transactions.Thus,additional technologies are required to ensure that the source of blockchain data is reliable.In this paper,the detailed procedure is designed for the application-oriented task validation in the blockchainenhanced computing resource sharing and transactions in ultra dense networks(UDN).The corresponding queuing model is built and analyzed with the consideration of the wireless re-transmission and the probability of malicious deception by users.Based on the analysis results,the UDN deployment is optimized to save network cost while ensuring latency performance.Numerical results verify our analysis,and the optimized system deployment including the number and service capacities of both base stations and mobile edge computing(MEC)servers are also given with various system settings. 展开更多
关键词 blockchain queuing theory wireless resource sharing validation procedure
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Validity and Reliability of the Preference for and Tolerance of the Intensity of Exercise Questionnaire among Chinese College Students
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作者 Ting Wang Jin Kuang +5 位作者 Fabian Herold Alyx Taylor Sebastian Ludyga Zhihao Zhang Arthur FKramer Liye Zou 《International Journal of Mental Health Promotion》 2023年第1期127-138,共12页
The rising prevalence of physical inactivity is in all age groups(e.g.,in college students)a major public health issue as not meeting the recommended minimum amount of regular physical activity is linked to adverse he... The rising prevalence of physical inactivity is in all age groups(e.g.,in college students)a major public health issue as not meeting the recommended minimum amount of regular physical activity is linked to adverse health events.Vice versa,there is mounting evidence that achieving the recommended amount of regular physical activity is a vital element to prevent chronic diseases,but there is often an insufficient adherence to planned and structured forms of physical activity(i.e.,physical exercises).In this context,there is a large body of evidence indicating that exercise adherence is,among other factors,influenced by exercise-related affective responses.The Preference for and Tolerance of the Intensity of Exer-cise Questionnaire(PRETIE-Q)has been developed to measure these affective responses(e.g.,to specific exercise inten-sities).So far,no validated Chinese version of the PRETIE-Q has been available in the literature.To address this gap in literature,the present study developed and validated a Chinese version of the PRETIE-Q in a large sample of Chinese college students.Data from a total of 1117 college students were collected for analyses concerning factorial validity and construct validity.The re-test reliability was established using a sample of 150 randomly selected participants.In addition,the level of regular physical activity(PA),cardiorespiratoryfitness(CRF),and resilience were used to examine possible links with two domains(preference and tolerance)of the PRETIE-Q.Our results showed that a Chinese version of the PRETIE-Q has a goodfit and reliability(Cronbach’sαof 0.72 to 0.85 for preference and tolerance,respectively;ICC:r=0.72 of preference and r=0.67 of tolerance;fit indices:χ^(2)=21.612,df=19,p>0.05,TLI=0.997,CFI=0.998,RMSEA=0.016,SRMR=0.024).Secondly,positive associations of intensity-tolerance with PA,CRF,and resilience were observed.In summary,this study indicates that the Chinese version of the PRETIE-Q has sound psychometric properties and can be used in Chinese college students.The adapted version of the PRETIE-Q paves the way for further research on exer-cise-related affective responses in Chinese-speaking samples,although the generalizability of ourfindings needs to be established for other cohorts such as adolescents and older people with and without chronic diseases. 展开更多
关键词 PRETIE-Q PLEASURE INTENSITY tolerance PREFERENCE validity
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Offshore Software Maintenance Outsourcing Process Model Validation:A Case Study Approach
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作者 Atif Ikram Masita Abdul Jalil +3 位作者 Amir Bin Ngah Adel Sulaiman Muhammad Akram Ahmad Salman Khan 《Computers, Materials & Continua》 SCIE EI 2023年第3期5035-5048,共14页
The successful execution and management of Offshore Software Maintenance Outsourcing(OSMO)can be very beneficial for OSMO vendors and the OSMO client.Although a lot of research on software outsourcing is going on,most... The successful execution and management of Offshore Software Maintenance Outsourcing(OSMO)can be very beneficial for OSMO vendors and the OSMO client.Although a lot of research on software outsourcing is going on,most of the existing literature on offshore outsourcing deals with the outsourcing of software development only.Several frameworks have been developed focusing on guiding software systemmanagers concerning offshore software outsourcing.However,none of these studies delivered comprehensive guidelines for managing the whole process of OSMO.There is a considerable lack of research working on managing OSMO from a vendor’s perspective.Therefore,to find the best practices for managing an OSMO process,it is necessary to further investigate such complex and multifaceted phenomena from the vendor’s perspective.This study validated the preliminary OSMO process model via a case study research approach.The results showed that the OSMO process model is applicable in an industrial setting with few changes.The industrial data collected during the case study enabled this paper to extend the preliminary OSMO process model.The refined version of the OSMO processmodel has four major phases including(i)Project Assessment,(ii)SLA(iii)Execution,and(iv)Risk. 展开更多
关键词 Offshore outsourcing process model model validation vendor challenges case study
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An Adaptive Parameter-Free Optimal Number of Market Segments Estimation Algorithm Based on a New Internal Validity Index
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作者 Jianfang Qi Yue Li +3 位作者 Haibin Jin Jianying Feng Dong Tian Weisong Mu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第10期197-232,共36页
An appropriate optimal number of market segments(ONS)estimation is essential for an enterprise to achieve successful market segmentation,but at present,there is a serious lack of attention to this issue in market segm... An appropriate optimal number of market segments(ONS)estimation is essential for an enterprise to achieve successful market segmentation,but at present,there is a serious lack of attention to this issue in market segmentation.In our study,an independent adaptive ONS estimation method BWCON-NSDK-means++is proposed by integrating a newinternal validity index(IVI)Between-Within-Connectivity(BWCON)and a newstable clustering algorithmNatural-SDK-means++(NSDK-means++)in a novel way.First,to complete the evaluation dimensions of the existing IVIs,we designed a connectivity formula based on the neighbor relationship and proposed the BWCON by integrating the connectivity with other two commonly considered measures of compactness and separation.Then,considering the stability,number of parameters and clustering performance,we proposed the NSDK-means++to participate in the integrationwhere the natural neighbor was used to optimize the initial cluster centers(ICCs)determination strategy in the SDK-means++.At last,to ensure the objectivity of the estimatedONS,we designed a BWCON-based ONS estimation framework that does not require the user to set any parameters in advance and integrated the NSDK-means++into this framework forming a practical ONS estimation tool BWCON-NSDK-means++.The final experimental results showthat the proposed BWCONand NSDK-means++are significantlymore suitable than their respective existing models to participate in the integration for determining theONS,and the proposed BWCON-NSDK-means++is demonstrably superior to the BWCON-KMA,BWCONMBK,BWCON-KM++,BWCON-RKM++,BWCON-SDKM++,BWCON-Single linkage,BWCON-Complete linkage,BWCON-Average linkage and BWCON-Ward linkage in terms of the ONS estimation.Moreover,as an independentmarket segmentation tool,the BWCON-NSDK-means++also outperforms the existing models with respect to the inter-market differentiation and sub-market size. 展开更多
关键词 Optimal number of market segments internal validity index cluster connectivity SDK-means++ market segmentation
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Validation of the multi-satellite merged sea surface salinity in the South China Sea
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作者 Huipeng WANG Junqiang SONG +3 位作者 Chengwu ZHAO Xiangrong YANG Hongze LENG Nan ZHOU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第6期2033-2044,共12页
Sea surface salinity(SSS)is an essential variable of ocean dynamics and climate research.The Soil Moisture and Ocean Salinity(SMOS),Aquarius,and Soil Moisture Active Passive(SMAP)satellite missions all provide SSS mea... Sea surface salinity(SSS)is an essential variable of ocean dynamics and climate research.The Soil Moisture and Ocean Salinity(SMOS),Aquarius,and Soil Moisture Active Passive(SMAP)satellite missions all provide SSS measurements.The European Space Agency(ESA)Climate Change Initiative Sea Surface Salinity(CCI-SSS)project merged these three satellite SSS data to produce CCI L4SSS products.We validated the accuracy of the four satellite products(CCI,SMOS,Aquarius,and SMAP)using in-situ gridded data and Argo floats in the South China Sea(SCS).Compared with in-situ gridded data,it shows that the CCI achieved the best performance(RMSD:0.365)on monthly time scales.The RMSD of SMOS,Aquarius,and SMAP(SMOS:0.389;Aquarius:0.409;SMAP:0.391)are close,and the SMOS takes a slight advantage in contrast with Aquarius and SMAP.Large discrepancies can be found near the coastline and in the shelf seas.Meanwhile,CCI with lower RMSD(0.295)perform better than single satellite data(SMOS:0.517;SMAP:0.297)on weekly time scales compared with Argo floats.Overall,the merged CCI have the smallest RMSD among the four satellite products in the SCS on both weekly time scales and monthly time scales,which illustrates the improved accuracy of merged CCI compared with the individual satellite data. 展开更多
关键词 sea surface salinity(SSS) South China Sea(SCS) ARGO multi-satellite merged data validATION
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Wheel-rail contact model for railway vehicle-structure interaction applications:development and validation
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作者 P.A.Montenegro R.Calçada 《Railway Engineering Science》 2023年第3期181-206,共26页
An enhancement in the wheel-rail contact model used in a nonlinear vehicle-structure interaction(VSI)methodology for railway applications is presented,in which the detection of the contact points between wheel and rai... An enhancement in the wheel-rail contact model used in a nonlinear vehicle-structure interaction(VSI)methodology for railway applications is presented,in which the detection of the contact points between wheel and rail in the concave region of the thread-flange transition is implemented in a simplified way.After presenting the enhanced formulation,the model is validated with two numerical applications(namely,the Manchester Benchmarks and a hunting stability problem of a sus-pended wheelset),and one experimental test performed in a test rig from the Railway Technical Research Institute(RTRI)in Japan.Given its finite element(FE)nature,and contrary to most of the vehicle multibody dynamic commercial software that cannot account for the infrastructure flexibility,the proposed VSI model can be easily used in the study of train-bridge systems with any degree of complexity.The validation presented in this work proves the accuracy of the proposed model,making it a suitable tool for dealing with different railway dynamic applications,such as the study of bridge dynamics,train running safety under different scenarios(namely,earthquakes and crosswinds,among others),and passenger riding comfort. 展开更多
关键词 Vehicle-structure interaction Wheel-rail contact Manchester Benchmarks Thread-flange transition Dynamic analysis Model validation
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Validation of the Chinese Version of the Affective Exercise Experiences Questionnaire (AFFEXX-C)
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作者 Ting Wang Boris Cheval +8 位作者 Silvio Maltagliati Zachary Zenko Fabian Herold Sebastian Ludyga Markus Gerber Yan Luo Layan Fessler Notger GMüller Liye Zou 《International Journal of Mental Health Promotion》 2023年第7期799-812,共14页
Despite the well-established benefits of regular physical activity(PA)on health,a large proportion of the world population does not achieve the recommended level of regular PA.Although affective experiences toward PA ... Despite the well-established benefits of regular physical activity(PA)on health,a large proportion of the world population does not achieve the recommended level of regular PA.Although affective experiences toward PA may play a key role to foster a sustained engagement in PA,they have been largely overlooked and crudely measured in the existing studies.To address this shortcoming,the Affective Exercise Experiences(AFFEXX)questionnaire has been developed to measure such experiences.Specifically,this questionnaire was developped to assess the following three domains:antecedent appraisals(e.g.,liking vs.disliking exercise in groups),core affective exercise experiences(i.e.,pleasure vs.displeasure,energy vs.tiredness,and calmness vs.tension),and exercise motivation(i.e.,attraction vs.antipathy toward exercise).The current study aimed to validate a Chinese version of the AFFEXX questionnaire(AFFEXX-C).In study 1,722 Chinese college students provided data for analyses of factorial,convergent,discriminant,criterion validity,and test-retest reliability of the AFFEXX-C.In addition,1,300 college students were recruited in study 2 to further validate its structural model.Results showed that the AFFEXX-C demonstrates a goodfit and reliability.Additionally,results further supported the hypothesized model based on previous research:antecedent appraisals predicted core affective exercise experiences,which in turn predicted attraction-antipathy toward physical exercise.The AFFEXX-C was found to be a reliable and valid measure of affective exercise experiences in a population of Chinese college students. 展开更多
关键词 Affective exercise experiences questionnaires RELIABILITY validity college students Chinese translation
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Validity and reliability of the Polish version of the Michigan Neuropathy Screening Instrument
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作者 Edyta Sutkowska Dominik Marciniak +6 位作者 Magdalena Koszewicz Edyta Dziadkowiak Slawomir Budrewicz Karolina Biernat Natalia Kuciel Justyna Mazurek Katarzyna Hap 《World Journal of Diabetes》 SCIE 2023年第4期435-446,共12页
BACKGROUND Diabetic sensorimotor polyneuropathy is an important risk factor for foot ulceration and amputation.Thus,patients with diabetes should be screened for this disorder according to local guidelines.An obstacle... BACKGROUND Diabetic sensorimotor polyneuropathy is an important risk factor for foot ulceration and amputation.Thus,patients with diabetes should be screened for this disorder according to local guidelines.An obstacle to the diagnosis of this disease may be the lack of unified diagnostic criteria due to the lack of properly validated scales used for assessment.AIM To validate both sections(A and B)of the Michigan Neuropathy Screening Instrument(MNSI)in Polish(PL)patients with diabetes.METHODS A cross-sectional study using a test(A1,B1)and re-test(A2,B2)formula was performed in 80 patients with diabetes.The gold standard used for neuropathy detection was a nerve conduction study(NCS)which was performed in all participants.Reliability of the MNSI-PL was assessed using the Cronbach’s alpha,Kuder-Richardson formula 20(KR-20),split-half reliability,the Gottman split-half tests,and correlation between first and second half was accessed.Stability was assessed using an intraclass correlation coefficient(ICC).For external validation,we used simple linear correlation,binomial regression,and agreement between two different tools using a Bland-Altman plot analysis.RESULTS The scale was internally consistent(Cronbach’s alpha for the full scale:0.81 for A and 0.87 for B).MNSI-PL scores in test/retest showed high stability(ICC=0.73 for A and ICC=0.97 for B).The statistically important correlations between MNSI-PL and NCS were found for B1,B2,and A1(P<0.005).The cut-off points of≥3 for section A(sensitivity of 90%-100%;specificity of 33%-40%)and≥2 for section B(sensitivity of 81%-84%;specificity of 60%-70%)were obtained during neuropathy detection.CONCLUSION The MNSI-PL is a reliable and valid instrument in screening for diabetic neuropathy. 展开更多
关键词 Michigan Neuropathy Screening Instrument validity RELIABILITY Diabetic neuropathy Chronic complications
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Analytical Method Development and Validation of Some Biosimilar Drugs by High Performance Thin Layer Chromatography
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作者 Husna Kanwal Qureshi Ciddi Veeresham 《American Journal of Analytical Chemistry》 2023年第3期121-133,共13页
A simple and rapid HPTLC analytical method has been developed and validated for the determination of Etanercept and Filgrastim in pure form and in marketed formulation. Both the drugs were chromatographed on silica ge... A simple and rapid HPTLC analytical method has been developed and validated for the determination of Etanercept and Filgrastim in pure form and in marketed formulation. Both the drugs were chromatographed on silica gel 60 F254s HPTLC plates, as stationary phase. The mobile phase optimized for Filgrastim and Etanercept was Water: n-butanol (7.5:2.5 v/v) and Isopropyl alcohol: water (6.5:4.5 v/v), respectively. The chromatogram obtained was scanned at 225 nm and 222 nm for filgrastim and etanercept which resulted in a retention factor of 0.45 ± 0.07 and 0.32 ± 0.03, respectively. The method was validated for parameters like linearity, accuracy, precision, specificity and robustness. Recovery studies were performed at three concentration levels, to demonstrate suitability, accuracy and precision of proposed method. Statistical analysis proved that the proposed method is accurate and reproducible with linearity in the range of 500 to 3000 ng/band for filgrastim and 200 to 1200 ng/band for etanercept. The limit of detection and limit of quantification for filgrastim was found to be 63.418 ng/band and 192.177 ng/band. For etanercept, LOD and LOQ were found to be 33.381 ng/band and 101.153 ng/band, respectively. The proposed method can be employed for the routine analysis of selected biosimilars. 展开更多
关键词 BIOSIMILARS ETANERCEPT FILGRASTIM Method Development validation
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Reliability and validity of the hidden hunger assessment scale in China-revised for high school students
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作者 Ning Zhang Minao Wang +6 位作者 Yuchen Zhang Huake Cao Yang Yang Yuhang Shi Yang Pei Feixiang Yang Yinan Du 《Global Health Journal》 2023年第2期110-116,共7页
Objective:Hidden hunger remains a severe public health problem that affects millions of people worldwide.In China,challenges related to dietary imbalance and hidden hunger persist.Micronutrient inadequacy deserves mor... Objective:Hidden hunger remains a severe public health problem that affects millions of people worldwide.In China,challenges related to dietary imbalance and hidden hunger persist.Micronutrient inadequacy deserves more attention among adolescents,given its vital role in their growth and development;however,this problem appears to have been largely ignored.High school students,in particular,are often at a high risk of hidden hunger but have limited assessment tools available.Therefore,this study aims to revise the hidden hunger assessment scale for high school students(HHAS-HSS)in China and assess its reliability and validity.Methods:Based on a literature review,expert consultation,pre-experiment,and formal survey,a hidden hunger assessment scale was revised for high school students.The formal survey involved 9336 high school students in 11 of the 16 cities in Anhui Province,China,and 9038 valid questionnaires were collected and included in the analysis.The item analysis,internal consistency reliability,test-retest reliability,content validity,exploratory factor analysis,and confirmatory factor analysis of the HHAS-HSS were examined.Results:The HHAS-HSS included a total of 4 dimensions and 12 items:"vegetables and food diversity"(three items),"fruits and dairy products"(three items),"micronutrient-dense foods"(four items),and"health condition and eating habits"(two items).The results showed a Cronbach's alpha of 0.758,a split-half reliability of 0.829,and a test-retest reliability of o.793,indicating good internal consistency.Using the Bartlett's test and Kaiser-Meyer-Olkin test(KMO)to test the exploratory factor analysis presented a four-factor model of the HHAS-HSS,the KMO0 value was 0.820(P<0.001),which indicated the possibility for factor confirmatory factor analysis.Using the maximum variance rotation method,four factors were obtained,and the cumulative variance explained rate was 57.974%.Confirmatory factor analysis also supported the division of the scale into four dimensions,and the fitting indices were x^(2)=1417.656,x^(2)/df=29.534,goodness-of-fit index=0.974,adjusted goodnessof-fit index=0.958,parsimonious goodness-of-fit index=0.600,normed fit index=0.938,incremental fit index=0.940,Tucker-Lewis index=0.917,comparative fit index=0.939,and root mean square error of approximation=0.056.Except for x^(2)/df,all the indices reached the fitting standard,and the above results showed that the construct validity of the scale reached an acceptable level.Conclusions:The HHAS-HSS has good validity and reliability for Chinese high school students.It is a convenient self-report measure of hidden hunger risk. 展开更多
关键词 Hidden hunger Reliability and validity Assessment scale High school student MICRONUTRIENTS
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