• 제목/요약/키워드: Local technology

검색결과 5,746건 처리시간 0.034초

Effect of local web buckling on the cyclic behavior of reduced web beam sections (RWBS)

  • Akrami, Vahid;Erfani, Saeed
    • Steel and Composite Structures
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    • 제18권3호
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    • pp.641-657
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    • 2015
  • Application of reduced web beam section (RWBS) as a sacrificial fuse element has become a popular research field in recent years. Weakening of beam web in these connections may cause local web buckling around the opening area which can affect cyclic behavior of connection including: maximum load carrying capacity, strength degradation rate, dissipated energy, rotation capacity, etc. In this research, effect of local web buckling on the cyclic behavior of RWBS connections is investigated using finite element modeling (FEM). For this purpose, a T-shaped moment connection which has been tested under cyclic loading by another author is used as the reference model. Fracture initiation in models is simulated using Cyclic Void Growth Model (CVGM) which is based on micro-void growth and coalescence. Included in the results are: effect of opening corner radii, opening dimensions, beam web thickness and opening reinforcement. Based on the results, local web buckling around the opening area plays a significant role on the cyclic behavior of connection and hence any parameter affecting the local web buckling will affect entire connection behavior.

Iterative global-local procedure for the analysis of thin-walled composite laminates

  • Afnani, Ashkan;Erkmen, R. Emre
    • Steel and Composite Structures
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    • 제20권3호
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    • pp.693-718
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    • 2016
  • This paper presents a finite element procedure based on Bridging multi-scale method (BMM) in order to incorporate the effect of local/cross-sectional deformations (e.g., flange local buckling and web crippling) on the global behaviour of thin-walled members made of fibre-reinforced polymer composite laminates. This method allows the application of local shell elements in critical regions of an existing beam-type model. Therefore, it obviates the need for using computationally expensive shell elements in the whole domain of the structure, which is otherwise necessary to capture the effect of the localized behaviour. Consequently, highly accurate analysis results can be achieved with this method by using significantly smaller finite element model, compared to the existing methods. The proposed method can be used for composite polymer laminates with arbitrary fibre orientation directions in different layers of the material, and under various loading conditions. Comparison with full shell-type finite element analysis results are made in order to illustrate the efficiency and accuracy of the proposed technique.

Economic Effect of Local Feed Utilization in Korea

  • Lee, Byung Oh;Yang, Jeong Hee;Park, Sang Youn;Lee, Byeong Soon
    • International Journal of Advanced Culture Technology
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    • 제6권4호
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    • pp.214-225
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    • 2018
  • Rice straw is the principal forage for Korean cattle. Limited supply of domestic forage forces Korea to depend on imported forage. Utilizing locally available domestic feed as an alternative would lead to self-sufficiency and stability in cattle farm management. Locally available feed can be utilized as forage. The challenge of collecting local feed has been overcome by machines that have been developed to harvest feed. Local feed can be completely consumed in the production regions, thus reducing transportation costs and increasing price competitiveness. Hitherto, studies have focused on feed technologies and price competitiveness, among other factors, while the substitution of forage has not been examined. This study conducts a quantitative analysis to estimate the extent to which local feed can replace existing forage. We find that local feed is cheaper, and abundantly available, and can thus replace high-quality forage.

LOCAL-GLOBAL PRINCIPLE AND GENERALIZED LOCAL COHOMOLOGY MODULES

  • Bui Thi Hong Cam;Nguyen Minh Tri;Do Ngoc Yen
    • 대한수학회논문집
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    • 제38권3호
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    • pp.649-661
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    • 2023
  • Let 𝓜 be a stable Serre subcategory of the category of R-modules. We introduce the concept of 𝓜-minimax R-modules and investigate the local-global principle for generalized local cohomology modules that concerns to the 𝓜-minimaxness. We also provide the 𝓜-finiteness dimension f𝓜I (M, N) of M, N relative to I which is an extension the finiteness dimension fI (N) of a finitely generated R-module N relative to I.

Comparison of Growth Performance, Carcass Characteristics and Meat Quality of Korean Local Chickens and Silky Fowl

  • Choo, Y.K.;Kwon, H.J.;Oh, S.T.;Um, J.S.;Kim, B.G.;Kang, C.W.;Lee, S.K.;An, B.K.
    • Asian-Australasian Journal of Animal Sciences
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    • 제27권3호
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    • pp.398-405
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    • 2014
  • This study was conducted to compare growth performance, carcass characteristics and meat quality of 4 breeds of local chicken. A total of 480 1-d-old chicks were distributed to 16 pens, with 4 treatments of breed, 4 replicates and 30 chicks per pen. Three Korean local breeds of white-mini broiler, Hanhyup-3-ho, and Woorimatdag, and a breed of silky fowl were raised under identical rearing and feeding conditions for 31-d, 37-d, 36-d, and 59-d, respectively. The BW and feed consumption on a pen basis were weekly measured for all pens, and ADFI, ADG and gain:feed were calculated for each pen. The ADFI and ADG of 3 breeds of Korean local chicken were greater than those of silky fowl (p<0.05). Within the Korean local breeds, ADFI of white-mini broiler was the highest (p<0.05), and ADG of Hanhyup-3-ho and white-mini broiler was the highest (p<0.05). Gain:feed of silky fowl was less than that of the 3 breeds of Korean local chicken. The carcass and breast yield of white-mini broiler were the greater than those of other breeds (p<0.05). The breast meat color (CIE $L^*$, $a^*$, and $b^*$) of 3 breeds of Korean local chicken were higher than that of silky fowl (p<0.05). The breast meat of Hanhyup-3-ho had greater cooking loss (p<0.05), whereas water holding capacity and pH were less than those of other breeds (p<0.05). The color score of 3 breeds of Korean local chicken was higher than that of silky fowl (p<0.05). Woorimatdag had a higher score on tenderness (p<0.05), whereas flavor score was less than that of other breeds (p<0.05). In conclusion, 4 local breeds of chicken have some unique features and seem to have more advantages, and this information can help consumers who prefer healthy and premium chicken meat.

An Efficient Method for Co-purification of Eggshell Matrix Proteins OC-17, OC-116, and OCX-36

  • Zhang, Maojie;Wang, Ning;Xu, Qi;Harlina, Putri Widyanti;Ma, Meihu
    • 한국축산식품학회지
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    • 제36권6호
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    • pp.769-778
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    • 2016
  • In this study, we improved the eggshell-membrane separation process by separating the shell and membrane with EDTA solution, evaluating effects of three different extraction solutions (acetic acid, EDTA, and phosphate solution), and co-purifying multiple eggshell proteins with two successive ion-exchange chromatography procedures (CM Sepharose Fast Flow and DEAE Sepharose Fast Flow). The recovery and residual rates of eggshell and membrane separated by the modified method with added EDTA solution were 93.88%, 91.15% and 1.01%, 2.87%, respectively. Ovocleidin-116 (OC-116) and ovocalyxin-36 (OCX-36) were obtained by loading 50 mM Na-Hepes, pH 7.5, 2 mM DTT and 350 mM NaCl buffer onto the DEAE-FF column at a flow rate of 1 mL/min, ovocleidin-17 (OC-17) was obtained by loading 100 mM NaCl, 50 mM Tris, pH 8.0 on the CM-FF column at a flow rate of 0.5 mL/min. The purities of OCX-36, OC-17 and OC-116 were 96.82%, 80.15% and 73.22%, and the recovery rates were 55.27%, 53.38% and 36.34%, respectively. Antibacterial activity test suggested that phosphate solution extract exhibited significantly higher activity against the tested bacterial strains than the acetic acid or EDTA extract, probably due to more types of proteins in the extract. These results demonstrate that this separation method is feasible and efficient.

지방자치제도와 지방자치단체 환경관리체계와의 관계에 관한 연구 - 광역자치단체의 환경조례를 중심으로 - (A Study on the Rerationships Between the Local Autonomy System and the Environmental Management by the Local Government in Korea - Especially on the Upper-local Governments -)

  • 나승원;성현찬;이노우에켄타로
    • 한국환경복원기술학회지
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    • 제12권4호
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    • pp.81-93
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    • 2009
  • This study has focused 302 environmental ordinances enacted from 1974 to 2008 by 16 upper-local governments (7 deignated cities and 9 provinces) and the relationships between them and the development of the Korean local autonomy system. The ordinances have been categorized into three types, the voluntary ones without any obligatory stipulations in laws, the optional ones based on laws, and the law based obligatory ones, which have been examined the enactment years and the contents of them. The local ordinances have been enacted in four periods with a few characteristics, which are "the pre-local-autonomy period (1974-1991)", "the introductory-local-autonomy period (1991-1995)", "the local-autonomy-developing period (1995-1999)", and "the mature-local-autonomy period (after 2000)", along the local autonomy development. 57 ordinances were enacted in the first period, 20 enacted in the second period, 46 enacted in the third period and 179 ordinances in the fourth period. The obligatory ordinances were the most in the first period and in the second period, while the voluntary ordinances were enacted most in the third period. 7 designated cities have pretty more ordinances, 160 in all, than 9 provinces, 142. The tendency to enact earlier in the metropolitan area, SeoulCity, IncheonCity and Gyeonggi province, than the others can be seen. It can be said that the establishment of the local autonomy in Korea had accelerated the development of the local environmental management.

Local & Global 모델을 이용한 용접구조물 변형 해석에 관한 연구 (The Analysis of Welding Deformation in Large Welded Structure by Using Local & Global Model)

  • 장경복;조시훈;장태원
    • Journal of Welding and Joining
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    • 제22권6호
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    • pp.25-29
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    • 2004
  • Some industrial steel structures are composed by components linked by several welding joints to constitute an assembly. The main interest of assembly simulation is to evaluate the global distortion of welded structure. The general method, thermo-elasto-plastic analysis, leads to excessive model size and computation time. In this study, a simplified method called "Local and Global approach" was developed to break down this limit and to provide a accurate solution for distortion. Local and global approach is composed of 3 steps; 1) Local simulation of each welding joint on a dedicated mesh (usually very fine due to high thermal gradients), taking into account for the non linearity of the material properties and the moving heat source. 2) Transfer to the global model of the effects of the welding joints by projection of the plastic strain tensors. 3) Elastic simulation to determine final distortions in global model. The welding deformation test for mock-up structure was performed to verify this approach. The predicted welding distortion by this approach had a good agreement with experiment results.

Local Similarity based Discriminant Analysis for Face Recognition

  • Xiang, Xinguang;Liu, Fan;Bi, Ye;Wang, Yanfang;Tang, Jinhui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권11호
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    • pp.4502-4518
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    • 2015
  • Fisher linear discriminant analysis (LDA) is one of the most popular projection techniques for feature extraction and has been widely applied in face recognition. However, it cannot be used when encountering the single sample per person problem (SSPP) because the intra-class variations cannot be evaluated. In this paper, we propose a novel method called local similarity based linear discriminant analysis (LS_LDA) to solve this problem. Motivated by the "divide-conquer" strategy, we first divide the face into local blocks, and classify each local block, and then integrate all the classification results to make final decision. To make LDA feasible for SSPP problem, we further divide each block into overlapped patches and assume that these patches are from the same class. To improve the robustness of LS_LDA to outliers, we further propose local similarity based median discriminant analysis (LS_MDA), which uses class median vector to estimate the class population mean in LDA modeling. Experimental results on three popular databases show that our methods not only generalize well SSPP problem but also have strong robustness to expression, illumination, occlusion and time variation.

AN EXPERIMENTAL STUDY ON THE EFFICIENCY OF A LOCAL VENTILATION SYSTEM AND THE PROTECTING FACE MASKS IN DENTAL LABORATORIES

  • Kim, Uoong-Chul
    • 대한치과기공학회지
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    • 제11권1호
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    • pp.95-102
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    • 1989
  • This study was performed to study the efficiency of a local ventilation system, installed in dental laboratories, and of two types of protecting face masks. The dust originating from the workpiece as well as from the wheels and stones was collected on air filters in the cutting cycle during coarse and fine grinding, and in the subsequent polishing procedures of each specific dental material. The efficiency of the ventilation system was measured on the basis of weight reduction of dust in the breathing air at a distance about 20-40 cm from workpiece. The results were as follows: 1. Use of the local ventilation system reduced the amounts of respirable dust to an average level of 21.4%, although the efficiency of the local ventilation system varied depending upon materials used. 2. Mounting a nozzle on the tube improved the efficiency of the ventilation system considerably. The efficiency of the local ventilation system also increased as the workpiece was closing to the tube inlet. 3. With or without the local ventilation system, the distance between the position of the workpiece and sampler greatly affected the dust level. 4. The face masks covering the sampler improved the efficiency of the ventilation system considerably.

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