• 제목/요약/키워드: Structural factor S(Q)

검색결과 19건 처리시간 0.022초

구난장갑차 크레인 브래킷에 대한 구조건전성 평가 (Structural Integrity Evaluation for Crane Bracket of Armored Recovery Vehicle)

  • 정재웅;정운화;김천수;유영수;박경철;박기철
    • 한국군사과학기술학회지
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    • 제16권5호
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    • pp.653-658
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    • 2013
  • For towing the new type armored vehicle and maintaining the close support, the armored recovery vehicle(ARV) with winch and crane has been developed. In case of crane, it is mainly used to salvage heavy objects by rotational and vertical motion. Especially, the crane bracket is very important parts due to fixing the ARV's body and rotary joint and preventing the force rotation of crane. Therefore, the crane bracket needs to have an enough strength to endure the high load and it is very important to analyze the stress distribution under loads. In the present work, the experimental and analytical investigation on structural integrity evaluation of crane bracket were carried out. The simulation of three-dimensional finite element method(FEM) was compared with experimental datum. From the numerical results, the FEM simulations corresponded well with th experimental results and the structural safety was confirmed by safety factor.

Balancing 모듈 설계를 위한 Differential Gear System의 구조해석에 관한 연구 (Structural Analysis of Differential Gear System for Balancing Module Design)

  • 장태환;김동준;문창호;이성재;김태규
    • 열처리공학회지
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    • 제32권6호
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    • pp.270-274
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    • 2019
  • In this study, simulation structure analysis was performed for the differential gear system for passenger cars as a prerequisite for the design of the balancing module. The differential gear system was modeled by using CATIA and simulation structure analysis was performed using ANSYS software. The material of the modeled differential gear system uses the mechanical properties of S45C (Q&T). In the structural analysis of the differential gear, the areas where the maximum stress and the maximum strain occurred can be identified. The maximum stress and maximum strain occurred in the pitch circle of the bevel gear. In evaluating the safety factor, it was found that sufficient safety factor was secured. Based on the analysis results for the differential gear, it is expected that it will be a good reference if we design the balancing module device.

MA법에 의한 V-Co계 비정질합금의 제조 및 구조분석 (Fabrication and structural observation of amorphous V-Co alloy by mechanical alloying)

  • 이충효
    • 한국결정성장학회지
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    • 제22권1호
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    • pp.51-56
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    • 2012
  • 본 연구에서는 출발원료로 ${\sigma}$-VCo 금속간화합물과 $V_{50}Co_{50}$ 혼합분말을 각각 사용하여 기계적 합금화에 따른 비정질화 가능성을 조사하였다. X선 회절에 의해 얻어진 전구조인자 S(Q) 및 동경분포함수 RDF(r)의 결과로부터 볼밀링이 진행됨에 따라 비정질상의 구조적 특징이 분명히 관찰되었다. 120시간 MA 처리에 의하여 두 경우 모두에서 비정질상이 생성됨을 알 수 있었다. 60시간 동안 MA 처리한 $V_{50}Co_{50}$ 분말시료의 열분석 에서는 약 $600^{\circ}C$에 비정질상의 결정화에 의한 발열 peak가 관찰되었다. X선 회절법에 의해 얻어진 전구조인자 및 동경분포함수의 분석으로부터 MA 시간에 따라 출발 결정상은 비정질상의 특징적인 원자구조로 서서히 변화함을 알 수 있었다.

여대생의 성역할에 관한 주관성 연구 (A Study of Subjectivity in the Perception Gender Roles of Women)

  • 권혜진;정연강;김경희;최미혜;염순교
    • 여성건강간호학회지
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    • 제9권1호
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    • pp.80-91
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    • 2003
  • Purpose : This study is to define the structural patterns of gender roles of women as perceived by co-eds. Method : Q-methodology was used on 174 statements collected through interviews with women aged between 20 an d 50. 38 Q-samples were selected from 330 Q-population. The Q-samples were administered to 29 co-eds. Result : Analysis of Q-type obtained by QUANAL program revealed three types of subjectivity in the perception of gender roles. Type 1, role is characterized by the tendency to play down the female gender role and think that women's body is an essential factor in forming the female gender role. Type 2, rejects motherhood image obedience and chastity dictated by male chauvinism. Type 3, shows a tendency to believeth at female gender cannot be separated from maternity and that women's basic role is housekeeping. The three types were common in believing in self-development and equal rights through economical in dependence.

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Fatigue life enhancement of defective structures by bonded repairs

  • Wang, Q.Y.;Kawagoishi, N.;Chen, Q.;Pidaparti, R.M.
    • Structural Engineering and Mechanics
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    • 제18권3호
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    • pp.277-286
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    • 2004
  • Defective metallic components and structures are being repaired with bonded composite patches to improve overall mechanical and fatigue properties. In this study, fatigue crack growth tests were conducted on pre-cracked 7075/T6 Aluminum substrates with and without bonded Boron/epoxy patches. A considerable increase in the fatigue life and a decrease in the stress intensity factor (SIF) were observed as the number of patch plies increased. The experimental results demonstrate that the patch configurations and patch thickness can enhance fatigue life by order of magnitude. Quantitative comparisons between analytical and experimental data were made, and the analytical model based on a modified Rose's analytical solution appears to best estimate the fatigue life.

자폐성장애 아동 부모의 삶의 전환과정 측정도구에 대한 구성타당도 평가 (Construct Validity of the Life Transition Scale for Parents of Children with Autism)

  • 이애란;홍선우;주세진
    • 대한간호학회지
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    • 제44권5호
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    • pp.563-572
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    • 2014
  • Purpose: The study was done to identify the construct validity and reliability of the life transition scale (LTS) for parents who have children with autism. Methods: Exploratory factor analysis (EFA) and confirmative factor analysis (CFA) were conducted to identify the most adequate measurement model for structural validity. Convergent validity and discriminant validity were also conducted for structural validity. Data were collected from 208 parents through self-reported questionnaires and analyzed with SPSS/WIN 15.0 and AMOS 20.0 version. Results: A four factor-structure was validated (${\chi}^2$=541.23, p<.001, GFI=.82, RMSEA=.07, IFI=.89, CFI=.89, PNFI=.73, Q (${\chi}^2/df$)=2.20) at the 3rd order of EFA and CFA, and factors were named as denying, wandering, despairing, and accepting. Both convergent and determinant validity for LTS were 100%. Cronbach's alphas for the reliability of each structure were .77-.90 and .83 for total structure. Conclusion: The four structures, 24-item instrument showed satisfactory reliability and validity. LTS has the potential to be appropriate for assessing the transition process of life for parents who have children with autism and provides basic directions for differentiated support and care at each stage.

Ductility demands and reduction factors for 3D steel structures with pinned and semi-rigid connections

  • Llanes-Tizoc, Mario D.;Reyes-Salazar, Alfredo;Ruiz, Sonia E.;Bojorquez, Eden;Bojorquez, Juan;Leal Graciano, Jesus M.
    • Earthquakes and Structures
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    • 제16권4호
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    • pp.469-485
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    • 2019
  • A numerical investigation regarding local (${\mu}_L$) and story (${\mu}_S$) ductility demand evaluation of steel buildings with perimeter moment resisting frames (PMRF) and interior gravity frames (IGF), is conducted in this study. The interior connections are modeled, firstly as perfectly pinned (PP), and then as semi-rigid (SR). Three models used in the SAC steel project, representing steel buildings of low-, mid-, and high-rise, are considered. The story ductility reduction factor ($R_{{\mu}S}$) as well as the ratio ($Q_{GL}$) of $R_{{\mu}S}$ to ${\mu}_L$ are calculated. ${\mu}_L$ and ${\mu}_S$, and consequently structural damage, at the PMRF are significant reduced when the usually neglected effect of SR connections is considered; average reductions larger than 40% are observed implying that the behavior of the models with SR connections is superior and that the ductility detailing of the PMRF doesn't need to be so stringent when SR connections are considered. $R_{{\mu}S}$ is approximately constant through height for low-rise buildings, but for the others it tends to increase with the story number contradicting the same proportion reduction assumed in the Equivalent Static Lateral Method (ESLM). It is implicitly assumed in IBC Code that the overall ductility reduction factor for ductile moment resisting frames is about 4; the results of this study show that this value is non-conservative for low-rise buildings but conservative for mid- and high-rise buildings implying that the ESLM fails evaluating the inelastic interstory demands. If local ductility capacity is stated as the basis for design, a value of 0.4 for $Q_{GL}$ seems to be reasonable for low- and medium-rise buildings.

알코올사용장애자의 음주관련 문제 분석을 위한 구조모형 (Structural Equation Model for the Analysis of Alcohol-related Problem of Alcohol Use Disorders)

  • 손희정;이원기;박영신;홍해숙
    • Journal of health informatics and statistics
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    • 제42권2호
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    • pp.192-198
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    • 2017
  • Objectives: This study was designed to construct and test the structural equation model for the alcohol-related problem of alcohol use disorders. Methods: Data were collected by structured self-questionnaires from 229 male subjects who received > 8 (greater than 8) score on Alcohol Use Disorder Identification Test (AUDIT). The Data were analyzed by SPSS 21.0 and AMOS 21.0. Results: The model fit indices for the modified hypothetical model showed Q = 2.50, GFI = 0.90, and CFI = 0.94. As a result, Life position, parent's drinking problem, and alcohol expectancy had significantly direct effect on alcohol-related problem. Alcohol expectancy also had mediator effect between life position and alcohol-related problem. Conclusions: Consequently, the more positive life position, the less alcohol-related problem occurred. It is necessary to change their life position, which is individual factor, to prevent or reduce the alcohol related problem of alcohol use disorders.

3D-QSAR Studies of 8-Substituted-2-aryl-5-alkylaminoquinolines as Corticotropin-releasing Factor-1 Receptor Antagonists

  • Nagarajan, Santhosh Kumar;Madhavan, Thirumurthy
    • 통합자연과학논문집
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    • 제8권3호
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    • pp.176-183
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    • 2015
  • Corticotropin-releasing actor receptors (CRFRs) activates the hypothalamic pituitary adrenal axis, one of the 2 parts of the fight or flight response to stress. Increased CRH production has is associated with Alzheimer's disease and major depression and hypoglycemia. In this study, we report the important structural and chemical parameters for CRFR inhibitors using the derivatives of 8-substituted-2-aryl-5-alkylaminoquinolines. A 3D QSAR study, Comparative molecular field analysis (CoMFA) was performed. The best predictions were obtained for the best CoMFA model with a $q^2$ of 0.607 with 6 components and $r^2$ of 0.991. The statistical parameters from the generated CoMFA models indicated that the data are well fitted and have high predictive ability. The contour map resulted from the CoMFA models might be helpful in the future designing of novel and more potent CRFR derivatives.

Characteristic Variation of 3-D Solenoid Embedded Inductors for Wireless Communication Systems

  • Shin, Dong-Wook;Oh, Chang-Hoon;Kim, Kil-Han;Yun, Il-Gu
    • ETRI Journal
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    • 제28권3호
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    • pp.347-354
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    • 2006
  • The characteristic variation of 3-dimensional (3-D) solenoid-type embedded inductors is investigated. Four different structures of a 3-D inductor are fabricated by using a low-temperature co-fired ceramic (LTCC) process, and their s-parameters are measured between 50 MHz and 5 GHz. The circuit model parameters of each building block are optimized and extracted using the partial element equivalent circuit method and an HSPICE circuit simulator. Based on the model parameters, the characteristics of the test structures such as self-resonant frequency, inductance, and quality (Q) factor are analyzed, and predictive modeling is applied to the structures composed of a combination of the modeled building blocks. In addition, characteristic variations of the 3-D inductors with different structures using extracted building blocks are also investigated. This approach can provide a characteristic estimation of 3-D solenoid embedded inductors for structural variations.

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