• 소성∙가공
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• 제26권3호
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• pp.156-161
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• 2017

In this study, the reason of die fracture occurring in hot forging of an aluminum fixed scroll was studied, based on experiments and finite element predictions. The material is assumed to be rigid-viscoplastic, and the die is rigid for the finite element predictions. The stress in the tension at the wrap root is known to cause brittle fracture, and the increase in the tensile stress is owing to the unbalanced filling of material into the die cavities between both sides of the warp. Based on the empirical and numerical achievements, the effects of geometrical parameters of the material on the die fracture were examined to find practical measures for elongated die life. It has been shown from the parametric study that the material with the optimized trapezoidal cross-section, which can be easily made during cutting or the optimized cylindrical billet with its eccentric placement in the die cavity, can considerably reduce the magnitude of the tensile stress around the die corner fractured, indicating that economical manufacturing with reduced number of stages and elongated die life can be realized at once using the optimized practical initial material.

• 패션비즈니스
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• 제10권2호
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• pp.147-165
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• 2006

The purpose of this study was to develop design of maternity dress combined with nursing. Six maternity wears combined with nursing were developed through the literature, preceding studies, and web sites those were about pregnancy, breast feeding, a maternity wear, and a nursing wear. The results of this study were as follows: 1. In order to develop clothes of diverse styles and designs, an after five dress, a poncho style blouse, wrap culotte as well as a skirt suit, a pants suit, an one-piece dress were designed. 2. It was established to make more amounts of front ease than those of back ease and to supplement a frontal hanging portion in consideration of breast development and abdominal prominence. 3. In order to make use of a maternity wear after a birth, stretch fabric was used for an abdominal part or whole clothes. Also an empire line and pleats, a poncho style, a shirts blouse, and inserting a string were used for it. 4. the fabrics of cotton, mixed cotton, polyester were used because pregnant women and nursing mothers perspires more than others do. 5. The horizontal, vertical, diagonal slits for a breast feeding were made. The storm flap of a trench coat, a machine pleated fabric, a poncho, a bolero style were used for a nursing cover.

• 한국자동차공학회논문집
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• 제19권5호
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• pp.82-91
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• 2011

In this paper, a planar model for mechanics of a vehicle/pedestrian collision incorporating road gradient is derived to evaluate the pre-collision speed of vehicle. It takes into account a few physical variables and parameters of popular wrap and forward projection collisions, which include horizontal distance traveled between primary and secondary impacts with the vehicle, launch angle, center-of-gravity height at launch, distance from launch to rest, pedestrian-ground drag factor, the pre-collision vehicle speed and road gradient. The model including road gradient is derived analytically for reconstruction of pedestrian collision accidents, and evaluates the vehicle speed from the pedestrian throw distance. The model coefficients have physical interpretations and are determined through direct calculation. This work shows that the road gradient has a significant effect on the evaluation of the vehicle speed and must be considered in accident cases with inclined road. In additions, foreign/domestic empirical cases and multibody dynamic simulation results are used to construct a least-squares fitted model that has the same structure of the analytical one that provides an estimate of the vehicle speed based on the pedestrian throw distance and the band within which the vehicle speed would be expected to be in 95% of cases.

• 디지털융복합연구
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• 제11권3호
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• pp.59-71
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• 2013

클라우드 서비스(아마존 웹서비스 등)를 활용하여 글로벌 경쟁력을 갖춘 중소업체의 온라인 서비스(예. Zynga, 파프리카랩)가 등장하거나 금융시장 분석서비스가 클라우드를 활용하는 등 클라우드의 활용도가 높아지고 있으나, 국내 중소기업의 클라우드 이용은 아직 낮은 수준에 머물고 있다. 특히, PaaS(플랫폼 클라우드)가 성장하면서 모듈화된 인터넷 도구를 손쉽게 활용하여 비즈니스를 개발하는 행태가 증가할 것으로 전망되는 만큼, 국내기업의 IT부문 경쟁력 제고를 위하여 국내외 도입 성공사례를 연구하였다.

• 한방안이비인후피부과학회지
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• 제17권3호
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• pp.153-166
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• 2004

In addition to antiseptic／antibiotic regimens, current therapies such as topical and systemic corticosteroids, anti-histamine agents, immune suppressing agent are generally used in the western medicine to treat atopic dermatitis(AD). However, there is almost a complete lack of effective strategies to achieve long-term control of disease, oriental medical treatments are proposed an alternative measure. It has been proved by experimental and clinical study that Oriental medical atopic dermatitis(AD) treatments such as herb-medicine, acupuncture and moxibustion therapy, and steam therapy are effective in long-term treatment. Nevertheless, oriental medical therapy has some limitations to treat acute stage of the disease. Recently developed No-Hoe(蘆？: Aloe vera L.) extract dressings will be a supplementary methods to the oriental medical therapy. The dressing can subside pruritus, exudation, erythema and scaling in the acute stage of atopic dermatitis(AD). We applied the No-Hoe(蘆？: Aloe vera L.) extract dressings to eight atopic dermatitis patients and got some good effects. This reports will provide an alternative choice for the oriental and westernal medical therapy for long-term AD treatment.

• 정보저장시스템학회논문집
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• 제2권3호
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• pp.169-177
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• 2006

In this study, we present the optimization of a head slider using kriging method in order to reduce lift-off force during unloading process with satisfying reliable flying attitude in steady state. To perform an optimization process efficiently, a simplified lift-off force model, which is a function of air bearing suction force and flying attitudes, is created by kriging method. The EMDIOS, which is the process integration and design optimization software developed by iDOT, is used to automatically wrap the analysis with the optimization and efficiently implements the repetitive works between analyzer and optimizer. An optimization problem is formulated to reduce the lift-off force during unloading process while satisfying the flying attitude in reliable range over the entire recording band and reducing the probability of contact between slider and disk. The simulation result shows that the amplitude of lift-off force of optimized L/UL slider is reduced about 62%, compared with that of initial slider model. It is demonstrated by the dynamics L/UL simulation that the optimum slider incorporated with the suspension is not only smoothly loaded onto disk but also properly unloaded onto the ramp.

• ETRI Journal
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• 제38권5호
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• pp.818-828
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• 2016

This paper proposes a reusable design for the merging process used in three-dimensional High Efficiency Video Coding (3D-HEVC), which can significantly reduce the implementation complexity by eliminating duplicated module redundancies. The majority of inter-prediction coding tools used in 3D-HEVC are utilized through a merge mode, whose extended merging process is based on built-in integration to completely wrap around the HEVC merging process. Consequently, the implementation complexity is unavoidably very high. To facilitate easy market implementation, the design of a legacy codec should be reused in an extended codec if possible. The proposed 3D-HEVC merging process is divided into the base merging process of reusing HEVC modules and reprocessing process of refining the existing processes that have been newly introduced or modified for 3D-HEVC. To create a reusable design, the causal and mutual dependencies between the newly added modules for 3D-HEVC and the reused HEVC modules are eliminated, and the ineffective methods are simplified. In an application of the proposed reusable design, the duplicated reimplementation of HEVC modules, which account for 50.7% of the 3D-HEVC merging process, can be eliminated while maintaining the same coding efficiency. The proposed method has been adopted as a normative coding tool in the 3D-HEVC international standard.

• Structural Engineering and Mechanics
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• 제39권2호
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• pp.207-221
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• 2011

This paper aims to study the behavior of short reinforced concrete columns confined with external glass Fiber Reinforced Polymers (GFRP) sheets under eccentric loads. The experimental part of the study was achieved by testing 9 specimens under eccentric compression. Three eccentricity ratios corresponding to e/t = 0, 0.10, 0.50 in one direction of the column were used. Specimens were divided into three groups. The first group was the control one without confinement. The second group was fully wrapped with GFRP laminates before loading. The third group was wrapped under loading after reaching 75% of failure loads of the control specimens. The third group was investigated in order to represent the practical case of strengthening a loaded column with FRP laminates. All specimens were loaded until failure. The results show that GFRP laminates enhances both failure load and ductility response of eccentrically loaded column. Moreover, the study also illustrates the effect of confinement on the first crack load, lateral deformation, strain in reinforcement and failure pattern. Based on the analysis of the experimental results, a simple model has been proposed to predict the improvement of load carrying capacity under different eccentricity ratios. The predicted equation takes into consideration the eccentricity to cross section depth ratio, the ultimate strength of GFRP, the thickness of wrapping laminate, and the time of wrapping (before loading and under loading). A good correlation was obtained between experimental and analytical results.

• Bulletin of the Korean Chemical Society
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• 제26권10호
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• pp.1543-1548
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• 2005

Two isostructural new alkaline earth germanium nitrides, $Sr_6Ge_5N_2\;and\;Ba_6Ge_5N_2$, were obtained as single crystals from constituent elements in molten Na. They both crystallize in space group $P_{mmn}$ (No. 59) with a = 4.0007(8), b = 17.954(3), c = 9.089(2) $\AA$, Z = 2, and a = 4.1620(2), b = 18.841(1), c = 9.6116(5) $\AA$, Z = 2, for $Sr_6Ge_5N_2\;and\;Ba_6Ge_5N_2$, respectively. Their crystal structure contains features for both Zintl and nitride phases: zigzag anionic chain of $_{\infty}Ge^{2-}$, and dumbbell-shaped bent anion of ${GeN_2}^{4-}$. Counter cations of Sr or Ba wrap these anionic units in a channel-like arrangement. Unlike in other germanium nitrides, bond lengths of both Ge-N arms of the ${GeN_2}^{4-}$, are same in $Sr_6Ge_5N_2\;and\;Ba_6Ge_5N_2$.

• 한국식생활문화학회지
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• 제9권4호
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• pp.335-340
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• 1994

The objective of this study was to determine effects of soybean oil(SO), cottonseed oil(CO) and ricebran oil(RO) on stability and flavor of yackwa. This study consisted of yackwa fried in 3 differnet oils, then stored for 0, 3, 6 weeks in normal wrap at room temp. or vaccum package at $4^{\circ}C$. The moisture, oil contents, Hunter color values(L, 'a' and 'b'), % free fatty acid(FFA), thiobarbituric acid(TBA) value and sensory scores for color, flavor and acceptability were analyzed. The foam height of the oil after frying was also determined. Yackwa fried in RO was more red('a'=11.43) than yackwa fried in SO(10.64) or CO(10.51). TBA value of yackwa showed no difference among frying oils. Yackwa fried in SO showed better acceptability than those fried in CO. Yackwa fried in RO showed similar acceptability to yackwa fried in SO. The % FFA and TBA value of yackwa averaged across oil and package showed increasing tendency during 6 weeks storage.