Earticle

PURPOSES : This paper presents a finite element model to accurately represent the soil-post interaction of single guardrail posts in sloping ground. In this study, the maximum lateral resistance of a guardrail post has been investigated under static and dynamic loadings, with respect given to several parameters including post shape, embedment depth, ground inclination, and embedment location of the steel post. METHODS : Because current analytical methods applied to horizontal ground, including Winkler's elastic spring model and the p-y curve method, cannot be directly applied to sloping ground, it is necessary to seek an alternative 3-D finite element model. For this purpose, a 3D FHWA soil model for road-base soils, as constructed using LS-DYNA, has been adopted to estimate the dynamic behavior of single guardrail posts using the pendulum drop test. RESULTS : For a laterally loaded guardrail post near slopes under static and dynamic loadings, the maximum lateral resistance of a guardrail post has been found to be reduced by approximately 12% and 13% relative to the static analysis and pendulum testing, respectively, due to the effects of ground inclination. CONCLUSIONS : It is expected that the proposed soil material model can be applied to guardrail systems installed near slopes.

In this study, the dynamic impact analysis for the passenger air-bag(PAB) module has been carried out by using FEM to predict the dynamic characteristics of vehicle ride safety against head impact. The impact performance of vehicle air-bag is directly related to the design parameters of passenger air-bag module assembly, such as the tie bar bracket's width and thickness, respectively, However, the product's design of PAB module parameters are estimated through experimental trial and error according to the designer's experience, generally. Therefore, the dynamic analysis of head impact test of the passenger air-bag module assembly of automobile is needed to construct the analytical methodology At first, the FE models, which are consist of instrument panel, PAB Module, and head part, are combined to the whole module system. Then, impact analysis is carried out by the explicit solution procedure with assembled FE model. And the dynamic characteristics of the head impact are observed to prove the effectiveness of the proposed method by comparing with the experimental results. The better optimized impact performance characteristics is proposed by changing the tie bracket's width md thickness of module. The proposed approach of impact analysis will provides an efficient vehicle to improve the design quality and reduce the design period and cost. The results reported herein will provide a better understanding of the vehicle dynamic characteristics against head impact.

Conentionally, LS factor for the USLE suggested by Wischmeier has been computed manually on topographic maps based on one dimensional approach. But outcomes of the equation could be severely affected by the convergence and divergence of surface runoff at complex terrains. Thus the objective of this research are to develop a method to automatically compute LS factor based on the multiple flow algorithm, and to test the accuracy of this method by comparing outcomes of this method to previous measurements or estimations of soil erosion. The program for the automatic calculation of LS factor was developed by utilizing Fox Pro 4.5, and outcomes of the program is designed to input to IDRISI. The accuracy test of LS factor was carried out by comparing the actual measurements of soil loss at two test sites in and around of Suwon. The calculated volume of soil erosion at Buju mountain, Mokpo, was also compared to the outcome of a previous research based on the LS factor calculated by the conventional onedimensional approach. The outcomes of this research are as follows. First, the computed L based on the multiple flow algorithm for concae slopes are greater than those of convex slopes,. Second, the estimated soil loss based on this method at the test site in Mokpo is much greater than the outcomes based on the conventional one-dimensional approach. It can e concluded that the application of this automatic calculation method of LS factor can improve the accuracy of USLE and facilitate soil erosion prevention methods.

본 논문에서는 최근 여러 분야에서 불확실성에 대한 예측을 위해 사용되는 Fuzzy 추론법을 OFDM(Othgonal Frequency Division Multiplexing)의 채널추정 방식에 적용함으로써 향상된 성능과 낮은 복잡도를 갖는 새로운 채널추정 방식을 제안하였다. 제안된 방식은 LS(Least Square) 채널추정 이전에 Pilot을 이용하여 Fuzzy추론법에 의하여 채널의 통계적 특성을 계산하고 이에 대한 보간을 해 줌으로써 채널추정 성능을 향상시키는 방식이다. QPSK(Quadrature Phase Shift Keying)를 적용한 시뮬레이션 결과 제안된 채널추정 방식은 MSE(Mean Square Error)가 $10^{-3}$인 지점에서 MMSE(Mimimum Mean Square Error) 채널추정 방식보다는 약 1.3 dB 정도 성능이 열화되는 것으로 나타났지만 LS 채널 추정 방식과 비교하면 약 5.5 dB 정도의 성능 이득이 있는 것으로 분석되었으며, SER(Symbol Error Rate)은 SNR(Signal to Noise Ratio)이 20 dB인 지점에서 MMSE 채널추정 방식과 제안된 채널추정방식이 각각 $10^{-1.96}$, $10^{-1.93}$ 정도로 유사한 성능을 보이는 것으로 분석되었고, LS 채널추정 방식 보다 약 $10^{-0.35}$ 정도 제안된 방식의 성능이 향상된 것으로 분석되었다.

In this paper, the new channel estimation was proposed that have the low complexity and high performance using Fuzzy inference method uses recently from various field for estimation about uncertainty in channel estimation of OFDM. Proposed method is channel estimation performance improve, calculation and interpolation for statistics character of channel using the pilot before LS channel estimation by Fuzzy inference method. Simulation result in QPSK proposed channel estimation method shows the enhancement of 5.5dB compared to the LS channel estimation and the deterioration of 1.3dB compared to the MMSE channel estimation in mean square error point $10^{-3}$. symbol error rate shows similarity performance the MMSE $10^{-1.96}$, proposed channel estimation $10^{-1.93}$ and enhancement of $10^{-0.35}$ compared to the LS channel estimation in signal to noise ratio point 20dB.

(1S,2S,3E,7E,11E)-3,7,11,15-cembratetraen-17,2-olide (LS-1), a marine cembrenolide diterpene, has anticancer activity against colon cancer cells such as HT-29, SNU-C5/5-FU (fluorouracil-resistant SNU-C5) and SNU-C5. However, the action mechanism of LS-1 on SNU-C5 human colon cancer cells has not been fully elucidated. In this study, we investigated whether the anticancer effect of LS-1could result from apoptosis via the modulation of $Wnt/{\beta}$-catenin and the TGF-${\beta}$ pathways. When treated with the LS-1, we could observe the apoptotic characteristics such as apoptotic bodies and the increase of sub-G1 hypodiploid cell population, increase of Bax level, decrease of Bcl-2 expression, cleavage of procaspase-3 and cleavage of poly (ADP-ribose) polymerase in SNU-C5 cells. Furthermore, the apoptosis induction of SNU-C5 cells upon LS-1 treatment was also accompanied by the down-regulation of $Wnt/{\beta}$-catenin signaling pathway via the decrease of GSK-$3{\beta}$ phosphorylation followed by the decrease of ${\beta}$-catenin level. In addition, the LS-1 induced the activation of TGF-${\beta}$ signaling pathway with the decrease of carcinoembryonic antigen which leads to decrease of c-Myc, an oncoprotein. These data suggest that the LS-1 could induce the apoptosis via the down-regulation of $Wnt/{\beta}$-catenin pathway and the activation of TGF-${\beta}$ pathway in SNU-C5 human colon cancer cells. The results support that the LS-1 might have potential for the treatment of human colon cancer.

Prickly pear extract (PPE) was fermented by Lactobacillus rhamnosus LS at 3$0^{\circ}C$ for 2 days. To improve the physicochemical properties of fermented PPE, it was fortified with food polysaccharides (0.2 %) or seaweed calcium before lactic acid fermentation. The viable cell counts, flow behavior, titratable acidity and color stability of fermented PPE were evaluated during 4 weeks of cold storage. Addition of xanthan gum or glucomannan increased the apparent viscosity and acid production, viable cell counts and red color of PPE were also well maintained during the cold storage. However, fermenting PPE with gellan gum resulted in a decrease in relative absorbance, indicating lower color stability. In particular, PPE fortified with carrageenan or alginic acid showed reduced acid production and lower viable cell counts. Addition of seaweed calcium at a 0.1 % level had positive effects on color stability, and helped maintain viable cell counts of 4.1 ${\times}$ 10$^{9}$ CFU/mL. This study demonstrated that xanthan gum could be used as a good thickening agent and stabilizer for retaining viable cell counts and red color during the cold storage in PPE fermented by lactic acid bacteria.

최근 글로벌 경기침체의 영향으로 많은 기업들이 위기를 맞이하고 있다. 그 중 회생상황에 놓인 기업들은 회생 전략 중 하나인 구조조정을 통해 기업을 재도약시키려 하고 있다. 그러나 무리한 구조조정을 통해 핵심역량을 상실은 이후 재도약의 심각한 제약요인을 작용한다. 본 연구에서는 LS 전선의 성장경로를 성장기, 구조조정기, 재도약기로 나누어 이벤트 분석을 통하여 적절한 기업구조조정의 방식을 고찰 해 보고자한다. 연구방법으로는 Boyle and Desai`s의 회생전략 유형을 적용하여 분석 기간 내 LS 전선의 주요 이벤트들을 분류하여 분석하였다. 분석결과, LS 전선은 성장기에 양적, 질적 성장을 통해 글로벌기업으로 성장하였으나, 이러한 과정 중에 대규모 M&A 및 인수 후 통합 실패 등의 이유로 부채비율이 급증하여 유동성 문제가 야기되었다. 또한 윤리경영실패로 인한 일회성비용증가로 인해 대규모 구조조정 및 감량경영이 필요한 상황이었다. 구조조정기에 사업축소 및 자산매각, 인적분할 등을 통하여 비교적 성공적으로 구조조정이 마무리되고 재무건전성이 안정화되었다. 이후 재도약 및 회생을 위하여 고부가가치 사업으로의 전환과 비즈니스 모델 혁신, 철저한 품질경영 및 리스크 관리 등을 통해 재도약을 실현하였다. 본 연구결과의 주요 시사점은 학술적으로는 회생전략의 유형을 개념화한 이론적 틀을 활용하여 사례분석을 실시하였다는 것이다. 실무적으로는 사업재편 및 축소와 같이 감량경영과 핵심역량 유지 및 강화와의 상충관계를 설명하면서 균형감 있는 회생전략 실행의 중요성을 제시하였다는 것이다.

This study divides the growth path of LS Cable, a global cable & system company, into growth, restructuring and re-building. Through this analysis, we will examine the appropriate corporate restructuring strategies. As a research method, the main events of LS Cable & System in the analysis period were classified and analyzed by applying the regeneration strategy type of Boyle and Desai `s. As a result, LS Cable & System grew into a global company through quantitative and qualitative growth during its growth period. However, during this period, the debt ratio rose sharply due to large-scale M&A and PMI(Post Merger Integration) failures, resulting in liquidity problems. In addition, the related costs of ethical management failure increased. As a result, LS Cable & System carried out restructuring and downsizing. Since then, LS Cable has conducted business model innovation, thorough quality management and risk management for new growth. The main implication of this study is that the theoretical framework that conceptualized the type of regeneration strategy was used to analyze the case. In practical terms, it explained the importance of implementing a balanced turnaround strategy by explaining the trade-off between the turnaround strategy and core competence.

Recently the incidence of rollover accidents has increased due to the increase of SUV, and the probability of occupant injury in rollover accidents is very high, so research is needed accordingly. In this study, PC-CRASH, which is a program used for traffic accident analysis, is used for checking rollover speed and rollover angle of each situation in case of rollover accident, and applied to design variables of LS-DYNA which is finite element analysis program, so deformation displacements of roof according to collision velocity and angle were derived. Also, it is possible to predict rollover vehicle speed by using the derived value and the measured deformation displacement of roof in actual rollover accident, and it is possible to reconstruct accident more accurately by applying to PC-Crash which is traffic accident reconstruction program, so it is thought that it can be utilized analyzing traffic accident usefully.

차량방호울타리는 교통사고 발생 시 마지막 안전장치이다. 차량방호울타리의 구조적 성능 이 기대 수준 이상으로 유지가 되어야지만 운전자 혹은 차량 탑승자의 생명을 보호해 줄 수 있게 된다. 단부처리시설은 방호울타리의 끝단에 설치되며 차량 충돌 시 가드레일이 차 량에 관통하는 현상을 방지함과 동시에 충격을 흡수하는 형태의 시설물이다. 이러한 차량 방호울타리의 개발을 위하여 컴퓨터 시뮬레이션을 통한 반복해석을 수행함으로서 다양한 변수에 적절히 대응하는 방호울타리를 개발할 수 있을 것이다.

Road sides safety barrier system is the last safety during traffic accident. The structural performance of a roadside safety barrier should be kept above expectations. It is possible to protect the passenger's life. End treatment part is installed in the end of the barrier it prevents a phenomenon in which for the vehicle for the guardrail during a vehicle collision it is facility of the absorbing of car crashed impact. By repeated analysis through computer simulation for improving the vehicle crash it will be able to develop crash barriers to respond appropriately to various parameters.

본 논문은 계산량이 인 새로운 형태의 QRD-LS 적응 알고리즘을 제안한다. 제안한 알고리즘의 주요 사항은 입력벡터의 단위벡터 계산이 Given Rotation 과정에서 이루어짐에 근거하고 있다. 알고리즘의 성능 평가는 FIR 시스템 식별 문제를 컴퓨터 시뮬레이션을 통하여 수행하였다. 이 알고리즘은 시뮬레이션의 결과 좋은 성능을 나타내었다. 그리고 이론적으로 평균 측면에서 알고리즘이 최적 계수 벡터에 수렴함을 보였다

This paper proposes a new QRD-LS adaptive algorithm with computational complexity of . The main idea of proposed algorithm(D-QR-RLS) is based on the fact that the computation for the unit vector of is made from the process during Givens Rotation. The performance of the algorithm is evaluated through computer simulation of FIR system identification problem. As verified by simulation results, this algorithm exhibits a good performance. And, we can see the proposed algorithm converges to optimal coefficient vector theoretically.

본 논문은 주요 두 재벌인 GS그룹(2014년 재벌 순위 8위)과 LS그룹(16위)에서 오너 일가들이 어떤 방식으로 그룹의 경영을 지배하고 있는지를 비교 분석한다. GS그룹은 2005년에 그리고 LS그룹은 2004년에 LG그룹에서 분리되어 새롭게 형성되었다. (1) 두 그룹 지배구조의 가장 큰 특징은 ‘공동적이면 개별적인 지배구조’라는 점이다. 즉 그룹의 주요 회사들을 한편으로는 오너 일가들이 공동으로 다른 한편으로는 개별 일가별로 소유․경영하였다. 이는 다른 재벌들에서 찾아볼 수 없는 독특한 방식이다. (2) GS그룹에서는 허씨 7개 일가가 소유에 참여하였고 이들 중 5개 일가는 경영에도 참여하였다. 이 5개 일가는 그룹의 지주회사인 (주)GS는 공동으로 경영하였으며, 동시에 4개 일가는 지주회사체제에 편입되지 않은 주요 4개 회사(삼양통상, GS건설, 코스모앤컴퍼니, 승산)를 각각 1개씩 일가별로 경영하였다. (3) LS그룹에서는 구씨 3개 일가가 소유 및 경영 모두에 참여하였다. 이들 3개 일가는 그룹의 지주회사인 (주)LS는 공동으로 경영하였고, 그런 한편으로 1개 일가는 지주회사체제에 편입되지 않은 주요 3개 회사 중 2개(예스코, 가온전선)를 그리고 다른 1개 일가는 나머지 1개 회사(E1)를 각각 일가별로 경영하였다. (4) 각 그룹에 여러 일가들이 함께 참여하게 되면서 자연스럽게 그리고 불가피하게 ‘공동적이면서 개별적인 지배구조’가 정착된 것으로 보인다. 두 그룹의 역사가 짧은 만큼 이러한 지배구조는 앞으로 상당 기간 지속될 것으로 판단되며, 미래의 어느 시기에 일가 중 일부가 분가할지에 대해서도 예의주시해야 할 것으로 보인다. GS그룹과 LS그룹 오너 일가의 경영지배구조를 비교 분석한 것은 본 연구가 처음이며, 이를 계기로 다른 재벌들에 대한 사례 및 비교ㆍ종합 연구가 진행될 수 있을 것으로 기대된다.

This paper delineates the ways in which the owner families in two major Korean chaebols, the Huh family in GS Group (8th largest chaebol in 2014) and the Koo family in LS Group (16th), were involved in the management. The two Groups were newly created, respectively in 2005 and in 2004, both from LG Group. (1) The most characteristic feature is that, in both Groups, a unique owner-control governance with both collaborative and individual elements has been established. That is, the key companies in each Group were owned and managed by the owner families together on one hand and by each of the families on the other. (2) In GS Group, a total of seven Huh families participated in ownership and five of them also in management. These five families were all involved in the management of the Group’s ‘holding company GS Corporation’ and, at the same time, four of these families governed each of ‘four de facto holding companies’ outside the holding company system. (3) Similarly, in LS Group, a total of three Koo families participated in not only ownership but also management. They were all involved in the management of the Group’s ‘holding companies LS Corporation’ and, at the same time, two families governed one or two of ‘three de facto holding companies’ outside the holding company system. (4) The owner-control style in GS Group and LS Group appears to have created ‘naturally and inevitably’ in the circumstances where a number of owner families became involved in each Group from the beginning. Given that both Groups have comparatively short histories, the present governance seems to continue to exist for a long period. The unique experience observed in GS Group and LS Group will, it is expected, shed a new light on corporate governance in many other Korean chaebols.