• Title/Summary/Keyword: structural evaluation

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The Physicochemical Change of Soybean-Leaf Water Kimchis during Fermentation (콩잎 물김치의 숙성과정 중 이화학적 변화)

  • 이봉희;김경자
    • Journal of the East Asian Society of Dietary Life
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    • v.13 no.6
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    • pp.601-607
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    • 2003
  • This study was attempted to investigate the physicochemical changes during soybean-leaf water kimchis fermentation by adding wheat flour in cooking water. Soybean-leaf water kimchis with five different levels of wheat flour in cooking water(0%;A, 5%;B 10%;c, 15%;D, 20%;E) were tested for rhological parameters, fine structural changes, sensory evaluations and chemical analysis. The composition of the soybean-leaf was moisture (80.9%), protein(6.8%), fat(0.6%), ash(2.1%) and alkalinity (+14.9). The amount of reducing sugars of sample A and other samples were 0.75% and 1.08∼1.4% in the initial fermentation stage, but decreased to 0.3 and 0.43∼0.50% in the later fermentation stage, respectively. The pH of sample A decreased from 5.17 to 4.72 during the initial fermentation. On sample B, C, D and E, pH's decreased rapidly during the initial fermentation, but they did not change much in the later fermentation stage. The pectin contents of all samples decreased during 2nd and 4th day of fermentation, then the change was slow. The amount of hemicellulose. cellulose and lignin in terms of the DNF and ADF were varied from 4 to 33%, but the contents of them did not greatly changed during the fermentation. The sensory evaluation showed that both B and C samples had the good score in sweety taste, roasted nutty taste, and the ease of swallowing measured as chewiness. From these results, the optimum soybean-leaf water kimchis can be prepared when 200g soybean-leaf, 1000$m\ell$ water, 15g garlic, 3% red pepper powder and 5 ∼0% wheat flour were fermented at 20$^{\circ}C$ for 2 days.

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Seismic Performance Evaluation of Piping System Crossing the Isolation Interface in Seismically Isolated NPP (면진 원전 면진-비면진구간 연결 배관의 내진성능 평가)

  • Hahm, Daegi;Park, Junhee;Choi, In-Kil
    • Journal of the Earthquake Engineering Society of Korea
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    • v.18 no.3
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    • pp.141-150
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    • 2014
  • A methodology to evaluate the seismic performance of interface piping systems that cross the isolation interface in the seismically isolated nuclear power plant (NPP) was developed. The developed methodology was applied to the safety-related interface piping system to demonstrate the seismic performance of the target piping system. Not only the seismic performance for the design level earthquakes but also the performance for the beyond design level earthquakes were evaluated. Two artificial seismic ground input motions which were matched to the design response spectra and two historical earthquake ground motions were used for the seismic analysis of piping system. The preliminary performance evaluation results show that the excessive relative displacements can occur in the seismically isolated piping system. If the input ground motion contained relatively high energy in the low frequency region, we could find that the stress response of the piping system exceed the allowable stress level even though the intensity of the input ground motion is equal to the design level earthquake. The structural responses and seismic performances of piping system were varied sensitively with respect to the intensities and frequency contents of input ground motions. Therefore, for the application of isolation system to NPPs and the verification of the safety of piping system, the seismic performance of the piping system subjected to the earthquake at the target NPP site should be evaluated firstly.

Evaluation of behavior of updated three-dimensional panel under lateral load in both independent and dependent modes

  • Rezaifar, Omid;Nik, Hamun Adeli;Ghohaki, Majid
    • Earthquakes and Structures
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    • v.14 no.1
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    • pp.11-20
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    • 2018
  • Three-dimensional panels are one of the modern construction systems which can be placed in the category of industrial buildings. There have always been a lot of studies and efforts to identify the behavior of these panels and improve their capacity due to their earthquake resistance and high speed of performance. This study will provide a comparative evaluation of behavior of updated three-dimensional panel's structural components under lateral load in both independent and dependent modes. In fact, this study tries to simultaneously evaluate strengthening effect of three-dimensional panels and the effects of system state (independent, L-shaped and BOX shaped Walls) with reinforcement armatures with different angles on the three-dimensional panels. Overall, six independent wall model, L-shaped, roofed L-shaped, BOX-shaped walls with symmetric loading, BOX -shaped wall with asymmetrical loading and roofed BOX-shaped wall were built. Then the models are strengthened without strengthened reinforcement and with strengthened reinforcements with an angle of 30, 45 and 60 degrees. The applied lateral loading, is exerted by changing the location on the end wall. In BOX-shaped wall, in symmetric and asymmetric loading, the load bearing capacity will be increased about 200 and 50% respectively. Now, if strengthened, the load bearing capacity in symmetric and asymmetric loading will be increased 3.5 and 2 times respectively. The effective angle of placement of strengthened reinforcement in the independent wall is 45 and 60 degrees. But in BOX-shaped and L-shaped walls, the use of strengthened reinforcement 45 degrees is recommended.

Development of Program for Producing Design-Data on Abbe-König Prism (아베-코닉 프리즘의 설계-데이터 산출 프로그램 개발)

  • Lee, Dong-Hee;Park, Seung-Hwan
    • Journal of the Korea Convergence Society
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    • v.8 no.12
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    • pp.299-305
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    • 2017
  • This study relates to the development of a program for calculating the design data and estimating on the Abbe-$K{\ddot{o}}nig$ prism. First, we set the Abbe-$K{\ddot{o}}nig$ prism design variables and derive the relational expressions between them. With this expressions, we could develope the program that outputs the numerical data for the Abbe-$K{\ddot{o}}nig$ prism design and three evaluation data for the Abbe-$K{\ddot{o}}nig$ prism analysis when the face-length, the effective convergent incident angle of incident beam, and the refraction index of prism are given. In fact, applying this program to the prism which is not the commercial size, we were able to calculate the design data very quickly, and we could easily understand the optical structure of the designed Abbe-$K{\ddot{o}}nig$ prism by the three evaluation data. This means that we can quickly ensure the structural data of the Abbe-$K{\ddot{o}}nig$ prism which is required for the product development.

The Study on the Disciplinary Model in Div. Military Science (대학 군사학과 훈육 모델에 관한 연구)

  • Kim, Sung Woo
    • Convergence Security Journal
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    • v.14 no.6_1
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    • pp.3-12
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    • 2014
  • The purpose of this study is to identify disciplinary professors' core competencies in Div. Military Science student. To best accomplish the study, I select core competencies in the precedent study about Disciplinary Professors' Core Competencies studies. The 5 factors of core competencies are as follow ; teaching core competency, evaluation core competency, guidance core competency, class management core competency, speciality development core competency. Through this study I developed disciplinary process model. This model is conducted to fit the structural relationship among the disciplinary professors' core competencies and students' life satisfaction and aspiration for military occupation. But this study has some restriction, so we should study actual proof the more.

Development of the Advanced NDI Technique Using an Alternating Current : the Evaluation of surface crack and blind surface crack and the detection of defects in a field component (교류전류를 이용한 새로운 비파괴탐상법의 개발;표면결함과 이면결함의 평가 및 실기 부재의 결함 검출)

  • Kim. H.;Lim, J.K.
    • Journal of Welding and Joining
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    • v.13 no.2
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    • pp.42-52
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    • 1995
  • In the evaluation of aging degradation on the structural materials based on the fracture mechanics, the detection and size prediction of defect are very important. Aiming at nondestructive detection and size prediction ol defect with high accuracy and resolution, therefore, an lnduced Current Focusing Potential Drop(ICFPD) technique has been developed. The principle of this technique is to induce a focusing current at an exploratory region by an induction wire flowing an alternating current(AC) that is a constant ampere and frequency. Defects are assessed with the potential drops that are measured the induced current on the surface of metallic material by the potential pick-up pins. In this study, the lCFPD technique was applied for evaluating the location and size of the surface crack and blind crack made in plate specimens, and also for detecting the defects existing in valve, a field component, that were developed by SCC etc. during the service. The results of this present study show that surface crack and blind crack are able to defect with potential drop. these cracks are distinguished with the distribution of potential drop, and the crack depths can be estimated with each normalized potential drop that are parameters estimating the depth of each type crack. In the field component, the defects estimated by experiment result correspond with those in the cutting face of the measuring point within a higher sensitivity.

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Causal relationship between learning motivation and thinking in programming education using online evaluation tool (온라인 평가 도구를 활용한 프로그래밍 교육에서 학습 동기와 사고력 간 인과 관계)

  • Chang, Won-Young
    • Journal of The Korean Association of Information Education
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    • v.24 no.4
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    • pp.379-390
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    • 2020
  • Recently, interest in online teaching·learning and evaluation tools has increased in the context of Covid-19. In order to use tools effectively, it is necessary to identify the structural influence and causal relationship between the learner's affective and cognitive variables. In this study, to identify a causal relationship between motivation and thinking while using online judge, research and competing model were established and model fit/path analysis were performed. It was found that there was a linear causal relationship from tool usage, self-efficacy, flow, logical thinking, to computational thinking. It was confirmed that 'self-efficacy → flow', or 'flow' had mediating effect on the path from tool usage to thinking, and tool usage was not exerted to thinking through 'flow → self-efficacy'. The causality of 'logical thinking → computational thinking' was identified on the path where tool usage affects thinking ability through learning motivation, but the causality of 'computational thinking → logical thinking' was not identified.

Prediction of Weld Residual Stress of Narrow Gap Welds (협개선 용접부에 대한 용접잔류응력 예측)

  • Yang, Jun-Seog;Heo, Nam-Su
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.34 no.1
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    • pp.79-83
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    • 2010
  • The conventional welding technique such as shield metal arc welding has been mostly applied to the piping system of the nuclear power plants. It is well known that this welding technique causes the overheating and welding defects due to the large groove angle of weld. On the other hand, the narrow gap welding(NGW) technique has many merits, for instance, the reduction of welding time, the shrinkage of weld and the small deformation of the weld due to the small groove angle and welding bead width comparing with the conventional welds. These characteristics of NGW affect the deformation behavior and the distribution of welding residual stress of NGW, thus it is believed that the residual stress results obtained from conventional welding procedure may not be applied to structural integrity evaluation of NGW. In this paper, the welding residual stress of NGW was predicted using the nonlinear finite element analysis to simulate the thermal and mechanical effects of the NGW. The present results can be used as the important information to perform the flaw evaluation and to improve the weld procedure of NGW.

The Structural Economical Efficiency Evaluation of Partially Restrained Composite CFT Column-to-Beam Connection (합성반강접 CFT기둥-보 접합부 구조의 경제성 평가)

  • Kim, Sun-Hee;Bang, Jung-Seok;Park, Young-Wook;Choi, Sung-Mo
    • Journal of Korean Society of Steel Construction
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    • v.24 no.1
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    • pp.109-117
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    • 2012
  • This study seeks to devise a design application for a beam structure with partially restrained composite connection to a CFT column. A cost-efficient and stable component is applied by adjusting the stiffness ratio of the column connection through partially restrained composite connection. Based on a review of the structure's stability, it was confirmed that in the case of a low-rise building as a moment frame, resistance without bracing is feasible because stiffness increased by virtue of the partial restrained composite connection by composite action. In the case of a high-rise building, lateral resistance load of moment frame was approximately 10% when proper partial restrained rate was at around 60%. With considerations related to economic efficiency, the partial restriction effect of the beam component was significantly activated by the uniform load, but that of the beam activated by concentrated load was not significantly indicative. The analysis indicated that 60% partial restrained girder at the connection was the most economical in the case of uniform load. It also showed that end moments can be reduced by approximately 25%.

Damage Evaluation of Cracked Laminated Composite Plates Using Experimental Modal Analysis (실험 모드해석을 이용한 균열 적층복합판의 손상평가)

  • Kim, Joo-Woo
    • Journal of Korean Society of Steel Construction
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    • v.24 no.4
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    • pp.399-410
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    • 2012
  • In this study, vibration tests are performed on cantilevered and clamped-clamped laminated composite rectangular plates using experimental modal analysis technique. The damages are simulated by applying progressive line cracks to the laminated composite plates for damage evaluations due to crack growth. The changes of frequency response functions(FRFs), MAC values, and modal parameters (frequency, mode shape and damping ratio) of the damaged composite plates, which are obtained by the modal testing of impact hammer, are investigated. Each experimental modal parameter of the progressively damaged composite plates is compared with natural frequencies and mode shapes obtained by finite element analysis. It is seen that the damage can be evaluated from the changes in the geometric properties and structural behaviors of the laminated composite plates resulting from the model updating process of the finite element model as a benchmark.