• 한국가족관계학회지
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• 제23권3호
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• pp.201-228
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• 2018

Objectives: The objectives of this study were to classify never-married types of adult men and women and explore factors related to these types. Never-married types were categorized into 4 types according to continuity and voluntariness: continuous voluntary type; changed voluntary type; continuous non-voluntary type; and changed non-voluntary type. Factors related to types of being single were examined in terms of socio-demographic factors, individual and psychological factors (self-esteem, depression), dating relationship factors (current relationship status), original family factors (parental conflict, relationship with parents, parents' demand for marriage), marriage related factors (division of roles after marriage), and occupation related factors (work values, employment instability). Method: As for research method, a survey was conducted with never-married adult men and women between the ages of 35 and 49 living in Seoul, Gyeonggi or Incheon areas. Of 300 copies of questionnaire distributed, data from 295 copies were processed using SPSS 24.0 program for multinomial logit analysis. Results: The study results showed that, of never-married men respondents, continuous voluntary type accounted for 20.5%; changed voluntary type 18.9%; continuous non-voluntary type 49.6%; and changed non-voluntary type 11.0%. It was found that the factors related to continuous non-voluntary type among never-married men are age, religion, average monthly income, while the factors related to changed voluntary type are religion, self-esteem, depression, and frequency and strength of parental conflict, while the factor related to changed non-voluntary type men was living with parents. Examining never-married women respondents, it was found that, continuous voluntary type accounted for 33.9%; changed non-voluntary type 19.6%; continuous non-voluntary type 22.6%; and changed voluntary type 23.8%. The factor related to continuous non-voluntary type among never-married women was parents' demand for marriage, while the factors related changed voluntary type were age, depression and strength of parental conflict. Also, the factors related to changed non-voluntary type of never-married women were age, religion, living with parents, depression and parents' demand for marriage. Conclusion: In conclusion, it was found that continuous non-voluntary type formed the largest group among never-married men, whereas continuous voluntary type was the majority in never-married women. Both never-married men and women chose to remain single when they are living with their parents and their parental conflict is intense. Parents' demand for marriage was related to women, but not to men.

• 대한치과보철학회지
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• 제36권3호
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• pp.453-467
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• 1998

This study helps to clarify conflicting reports by comparing the physical properties and accuracy of complete denture processed by the pack and press technique, continuous- pressure injection technique(SR-Ivocap system) and Mark press technique. The 6 different specimens have been evaluated using the SEM, Impact test, DSC (Differential Scanning Calorimetry) and DMTA (Dynamic Mechanical Thermal Analysis). Each sample was made of SR-Ivocap resin and QC-20 resin by different processing methods. The results were as follows ; 1. As the result of the observation on the fracture surface of resin by use of SEM, sample SR-Ivocap resin cured by continuous pressure injection method showed the most homogeneous structure. This is why molecules in SR-Ivocap resin have no orientation. 2. As the result of the Impact test in order to measure the deformity, fracture energy and impact resistance of resin, the samples with QC-20 acrylic resin and SR-Ivocap resin cured by continuous pressure injection method were exellent. 3. In consequence of measuring ${\alpha}$-glass transition temperature by use of DSC on the basis of temperature change, the glass transition temperatures of sample QC-20 resin cured by pack and press method and sample SR-Ivocap resin cured by continuous pressure injection method were very similar. Thus volumetric stability could not be evaluated only by glass transition temperature. 4. In comparing volumetric stability data by DMTA, the glass transition temperature(Tg) showed $137.88^{\circ}C$ at sample QC-20 resin cured by pack and press method and $139.78^{\circ}C$ at sample SR-Ivocap resin cured by continuous pressure injection method. Therefore sample SR-Ivocap resin cured by continuous pressure injection method seems to be superior to sample QC-20 resin cured by pack and press method in the dimensional stability at high temperature. 5. In comparing storage modulus data by DMTA, the storage modulus of sample SR-Ivocap resin cured by continuous pressure injection method was higher than that of sample QC-20 resin cured by pack and press method. So. sample SR-Ivocap resin cured by continuous pressure injection method seems to be superior to sample QC-20 resin cured by pack and press method in impact strength.

• 한국지반공학회지:지반
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• 제10권4호
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• pp.153-166
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• 1994

본 논문에서는 연속재하압밀시험을 적용하여 준설토의 거동을 연구하고 얇은 판을 이용하여 준설토의 강도 시험을 실시하는 새로운 실험 방법을 고안하여 실험을 하였다. 이 경우 준설토의 유동적 특성은 Bingham 모델로 설명할 수 있다. 이러한 방법을 위하여 정적 관입시험과 유동적 관입시험을 실시하였는데 두 방법은 모두 합 리적이고 실용성이 있었다. 특히 실험을 통하여 얻은 결론에 따르면 점토질이 많은 흙이나 실트 질 흙 모두에 대해서 함수비가 액성한계의 두배보다 적어지면 강도가 급격히 증가하는 반면,소 성지수의 경우 소성지수로 정규화한 함수비값이 실트는 10, 점토는 5이하가 되면서 소성지수로 정규화한 함수비값의 강도가 급격히 증가함을 알 수 있었다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.1089-1094
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• 2004

Numerical methods to estimate behaviors of jointed rock mass can be roughly divided into two method : discontinuous model and continuum model. Generally, distinct element method (DEM) is applied in discontinuous model, and finite element method (FEM) or finite difference method (FDM) is utilized in continuum model. To predict a behavior of discontinuous model by DEM, it is essential to understand characteristics of joints developed in rock mass through field tests. However, results of field tests can not provide full information about rock mass because field tests is conducted in limited area. In this paper, discontinuous analysis by UDEC and continuous analysis by FLAC is utilized to estimate a behavior of a tunnel in jointed rock mass. For including discontinuous analysis in continuous analysis, joints in rock mass is considered by reducing rock mass properties obtained by RMR and decreasing shear strength of rock mass. By comparing and revising two analysis results, analysis results similar with practical behavior of a tunnel can be induced and appropriate support system is decided.

• 한국가스학회:학술대회논문집
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• 한국가스학회 2002년도 춘계학술발표회 논문집
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• pp.78-85
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• 2002

• Journal of Welding and Joining
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• 제20권2호
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• pp.42-49
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• 2002

• International Journal of Concrete Structures and Materials
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• 제11권1호
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• pp.45-58
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• 2017

Recent investigations have pointed out that current code provisions specifying that the stiffness of reinforced concrete elements is strength independent, and therefore can be estimated prior to any strength assignment, is incorrect. A strength allocation strategy, suitable for preliminary structural design of medium height wall-frame dual systems, is presented for allocating strength in such buildings and estimating the dependable rigidities. The design process may be implemented by either the approximate continuous approach or the stiffness matrix method. It is based on the concept of the inelastic equivalent single-degree-of-freedom system which, the last few years, has been used to implement the performance based seismic design. The aforesaid strategy may also be used to determine structural configurations of minimum rotation distortion. It is shown that when the location of the modal centre of rigidity, as described in author's recent papers, is within a close distance from the mass axis the torsional response is mitigated. The methodology is illustrated in ten story building configurations, whose torsional response is examined under the ground motion of Kobe 1995, component KJM000.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1362-1365
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• 2003

On this study. we improved the efficiency applying algorithm that is repeatedly using orthogonal array in discrete design space and filling a defect of gradient method in continuous design space. we showed optimal ply angle that maximized buckling strength of CFRP laminated composite plate without a hole and with a hole by each aspect ratio. In the case of CFRP laminated composite plate without a hole, we confirmed the reliance and efficiency of algorithm in comparison with the result optimization achievement repeatedly using statistical orthogonal array of experimental design.

• 대한기계학회논문집A
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• 제31권2호
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• pp.245-252
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• 2007

Since the new millennium, truss PCMs(Periodic Cellular Metals) have drawn attention because of their superior specific stiffness, strength and multi-functionality. Prior studies have focused on the structural design and optimization. Kagome truss PCM has been proved to have the higher resistance to plastic buckling, more plastic deformation energy and lower anisotropy than other truss PCMs. In this study, we introduce a new idea to fabricate multi-layered Kagome truss PCM from continuous wires which can gain high strength as in piano wires and can be controlled to be defect free owing to drawing process. The relative density, the stiffness and the strength under bending and compressive load are estimated through elementary mechanics and compared with the results from experiments and FEA. The failure mechanisms are analyzed, and also mechanical performance and production are discussed.

• 한국기계가공학회지
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• 제19권12호
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• pp.1-7
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• 2020

An experimental evaluation of bending fatigue strength for austempered ductile iron (ADI) spur gears was performed using a Zwick fatigue tester. The gear material was manufactured using vertical continuous casting, resulting in the radius of the graphite grains being smaller. The stress-number of cycles curve (S-N curve) for the bending fatigue strength of the ADI spur gears thus manufactured, without any specific surface treatments, was obtained using post-processing software. It was observed that when the reliability was 50%, the allowable root stress was 610 MPa. was calculated using an analytical method as well as the finite element method, and the difference between the values calculated using the two methods is only 7%. This study provides a reliable basis to rate the reliability design of small gearboxes in automation in the future.