• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.142-147
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• 2004

In this paper, a new procedure is proposed to accomplish the primary plus secondary stress(P+Q) at the 'structural element' instead of 'transition element'. For the P+Q evaluation, the calculated stresses by FEA are linearized along a stress classification line to extract the stress category, then the stress intensity is calculated to compare with the $3S_{m}$ limit. Also, in this paper, the 'design by analysis' criteria, adopted fundamental concepts and a new approach to calculate $K_{e}$ factors are explained. The new procedure combined with 3-D FEA has been applied to motor operated valve in order to the over conservatism and the rack of margin. The evaluation results show a good applicability and can be utilized for fatigue life evaluation by using P+Q.

• 한국환경보건학회지
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• 제26권3호
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• pp.55-60
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• 2000

Wire codes, introduced by Wertheimer and Leeper, are interesting largely because several case-control studies have reported associations between them and certain types of cancers, including childhood leukemia. This paper is concerned with the reliability of wire codes as a surrogate for residential electric and magnetic field, divided into four categories based on the electrical wiring within 40m of homes. To examine the correlation between spot measurements and wire codes, EMF was measured by using HI-3604 and classified by wire codes. The correlation between long-transformed RMS of magnetic field and wire codes was 0.81. But the correlation between log-transformed RMS of electric field and wire codes was 0.27. The results led us to determine a four category from of the Wertheimer and Leeper code that 1) may be useful in domestic epidemiological studies and 2) is not suitable for electric field exposure. Thus, the critical point of exposure assessment in residential magnetic field is to classify a wire code precisely.

• 대한수학회지
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• 제53권4호
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• pp.795-834
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• 2016

The main purpose of this paper is to propose a scheme of a proof of the nonsimpleness of the group $Homeo^{\Omega}$ ($D^2$, ${\partial}D^2$) of area preserving homeomorphisms of the 2-disc $D^2$. We first establish the existence of Alexander isotopy in the category of Hamiltonian homeomorphisms. This reduces the question of extendability of the well-known Calabi homomorphism Cal : $Diff^{\Omega}$ ($D^1$, ${\partial}D^2$)${\rightarrow}{\mathbb{R}}$ to a homomorphism ${\bar{Cal}}$ : Hameo($D^2$, ${\partial}D^2$)${\rightarrow}{\mathbb{R}}$ to that of the vanishing of the basic phase function $f_{\underline{F}}$, a Floer theoretic graph selector constructed in [9], that is associated to the graph of the topological Hamiltonian loop and its normalized Hamiltonian ${\underline{F}}$ on $S^2$ that is obtained via the natural embedding $D^2{\hookrightarrow}S^2$. Here Hameo($D^2$, ${\partial}D^2$) is the group of Hamiltonian homeomorphisms introduced by $M{\ddot{u}}ller$ and the author [18]. We then provide an evidence of this vanishing conjecture by proving the conjecture for the special class of weakly graphical topological Hamiltonian loops on $D^2$ via a study of the associated Hamiton-Jacobi equation.

• Environmental Engineering Research
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• 제25권1호
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• pp.52-61
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• 2020

The article examines the impact differences between producing concrete and asphalt. Both materials are widely used in the construction industry. Construction activities account for a large portion of greenhouse gases. Therefore, it is important to consider the Life Cycle Analysis (LCA) to reduce environmental impacts. In this study, the material processes were inputted into an LCA program called SimaPro. The database used for the study was Ecoinvent as it is one of the major databases within SimaPro. The materials were compared against impacts per kg of material produced as the functional unit. Each process was created using the materials, energy and transportation required to produce the materials. Waste streams were also included in the process to determine the impacts after the product was done with its useful life. Using the ReCiPe method, an LCA was conducted. Midpoint and endpoint categories were examined for both the productions. The processes had similar results for the human health and ecosystems categories; however asphalt was marginally higher for both. Asphalt had exceeded concrete in the resource impact category by 100 mPt. The results indicate that concrete is the more sustainable building material. Determination of various impacts of the materials is important for material selection.

• Journal of information and communication convergence engineering
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• 제15권1호
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• pp.43-48
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• 2017

Movie ratings are crucial for recommendation engines that track the behavior of all users and utilize the information to suggest items the users might like. It is intuitively appealing that information about the viewing preferences in terms of movie genres is sufficient for predicting a genre of an unlabeled movie. In order to predict movie genres, we treat ratings as a feature vector, apply a Bernoulli event model to estimate the likelihood of a movie being assigned a certain genre, and evaluate the posterior probability of the genre of a given movie by using the Bayes rule. The goal of the proposed technique is to efficiently use movie ratings for the task of predicting movie genres. In our approach, we attempted to answer the question: "Given the set of users who watched a movie, is it possible to predict the genre of a movie on the basis of its ratings?" The simulation results with MovieLens 1M data demonstrated the efficiency and accuracy of the proposed technique, achieving an 83.8% prediction rate for exact prediction and 84.8% when including correlated genres.

• Wind and Structures
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• 제19권5호
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• pp.523-540
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• 2014

This paper presents a comprehensive study of pressure developed on different faces of a 'Y' plan shape tall building using both numerical and experimental means. The experiment has been conducted in boundary layer wind tunnel located at Indian Institute of Technology Roorkee, India for flow condition corresponding to terrain category II of IS:875 (Part 3) - 1987, at a mean wind velocity of 10 m/s. Numerical study has been carried out under similar condition using computational fluid dynamics (CFD) package of ANSYS, namely ANSYS CFX. Two turbulence models, viz., $k-{\varepsilon}$ and Shear Stress Transport (SST) have been used. Good conformity among the numerical and experimental results have been observed with SST model yielding results of higher magnitude. Peculiar pressure distribution on certain faces has been observed due to interference effect. Furthermore, flow pattern around the model has also been studied to explain the phenomenon occurring around the model.

• Mass Spectrometry Letters
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• 제11권3호
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• pp.52-58
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• 2020

Histidine phosphorylation (pHis) is increasingly recognized as an important post translational modification (PTM) in regulating cellular functions in eukaryotes. In order to clarify the role of pHis in mammalian cell signaling system, a global phosphorylation study was performed in human prostate cancer cells, PC-3M, using a TiO₂ affinity chromatography. A total number of 307 pHis sites were identified on the 268 proteins among total identified 9,924 phosphorylation sites on 3,316 proteins. In addition, 22 pHis proteins were classified in enzyme category. This report provides the first database for the study of pHis in prostate cancer cells.

• 한국산림과학회지
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• 제94권5호통권162호
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• pp.291-301
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• 2005

Robinia pseudoacacia is one of most widely cultivated exotic species in Bulgaria. The total area of black locust plantations amounts to 2.9% of the total forest area of the country. 15.34% of the plantations are of management afforestations category, where the priority is given to timber production. They have been created on rich and moisture soils, which are the most appropriate for the species in order to achieve its biological potentials of high productivity. The rest of the available plantations in the country are planted on poorer and drier soils up to 600~800 m altitude. The high adaptive ability of the species to unsuitable environmental conditions as well as the high sprout potential was used for their creation. These stands are mainly done with the aim to protect and ameliorate damaged environments and production of small-size timber and fire woods. They are cultivated until 15-20 years and are revived by sprouts. Therefore the management goals searched, 45.69% of those forests are low productive and 38.97% with average productiveness. The present report deals with growth and productivity capacity of black locust plantations; production of sowing materials; production of reproductive and vegetative saplings for afforestation; the technological aspects of afforestation works; the management and use of black locust plantations as well as some more important diseases and pests affecting the species. The report is entirely based on Bulgarian scientific research works and experience with the Robinia preudoacacia. Recommendations for optimizing the use of species are given.

• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 2001년도 춘계학술대회논문집:21세기 신지식정보의 창출
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• pp.77-83
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• 2001

최근 암호학계에는 미국의 AES와 더불어 체세대 유럽 암호 표준화 프로젝트 (NESSIE)가 진행 중에 있다. 이 프로젝트의 동기식 스트림 암호 분야에서는 호주의 Simpson이 제안한 LILI-128 암호를 포함하여 6개의 후보가 제안된 상태이며, 상기 알고리즘들은 고속화를 위하여 병렬 형태로 설계 개념을 채택하려하고 있다. 본 논문에서는 스트림 암호의 고속화 설계 방안인 병렬 이동형 PS-LFSR의 구조를 살펴본 다음 여러 가지 형태의 비선형 결합함수에 대한 효율적인 구현 방안을 제안하였다. 즉, 비메모리-비선형 결합함수, 메모리-비선형 결합함수, 비선형 필터함수, 클럭조절형 결합함수 등 4가지 형태의 출력함수 형태에 대한 효율적인 병렬 구현 방안을 제안하였고, 합산 수열 발생기의 병렬구현 기법과 클럭조절형 LILI-128의 병렬구현 기법을 예시하여 안전성과 성능을 분석하였다.

• Steel and Composite Structures
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• 제13권3호
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• pp.295-308
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• 2012

This paper experimentally investigated the buckling capacity of built-up steel columns mainly, Cruciform Columns (CC) and Side-to-Side (SS) columns fabricated from two Universal Beam (UB) sections. A series of nine experimental tests comprised of three UB sections, three CC sections and three SS sections with different lengths were tested to failure to measure the ultimate axial capacity of each column section. The lengths used for each category of columns were 1.8, 2.0, and 2.2 m with slenderness ratios ranging from 39-105. The measured buckling loads of the tested specimens were compared with the predicted ultimate axial capacity using Eurocode 3, AISC LRFD, and BS 5959-1. It was observed that the failure modes of the specimens included flexural buckling, local buckling and flexural-torsional buckling. The results showed that the ultimate axial capacity of the tested cruciform and side-by-side columns were higher than the code predicted design values by up to 20%, with AISC LRFD design values being the least conservative and the Eurocode 3 design values being the most conservative. This study has concluded that cruciform column and side-to-side welded flange columns using universal beam sections are efficient built-up sections that have larger ultimate axial load capacity, larger stiffness with saving in the weight of steel used compared to its equivalent universal beam counterpart.