• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.838-849
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• 2010

It is inevitable to control the systematic failure to obtain the software safety integrity of embedded software installed in rolling stock. Because it is not possible to assess systematic failure integrity by quantitative methods, SILs are used to group documentation, methods, tools and techniques throughout software development lifecycle which, when used effectively, are considered to provide an appropriate level of confidence in the realization of a system to a stated integrity level. Normally, safety approval process is through generic product, generic application and specification application for. For safety approval on generic application of software based system, it is required to apply the certified software processes from the planning stage for the assigned SIL. As such, we will develop project specific application with high safety integrity within time limit of contractual delivery schedule through software assessment to the modified area with the re-use of certified software module and documentation. At this point, Hyundai Rotem has developed software processes applicable to support SIL 4 based on EN50128 which was assessed and certified by TUV SUD. This paper introduces the Hyundai Rotem's detailed approach and prospective action to achieve software safety integrity level.

• Geomechanics and Engineering
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• 제14권1호
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• pp.19-27
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• 2018

It follows from the basic principles of mechanics of deformable solids relating to the strength, stability and propagation of elastic waves that the Earth's inner core cannot exist in the form of a spherical structure in the assumed thermobaric conditions and calculation values of physico-mechanical parameters. Pressure level reaches a value that is significantly greater than the theoretical limit of medium strength in the model approximations at the surface of the sphere of the inner core. On the other hand, equilibrium state of the sphere is unstable on the geometric forming at much lower loads under the influence of the "dead" surface loads. In case of the action of "follower" loads, the assumed pressure value on the surface of the sphere is comparable with the value of the critical load of "internal" instability. In these cases, due to the instability of the equilibrium state, propagation of homogeneous deformations becomes uneven in the sphere. Moreover, the elastic waves with actual velocity cannot propagate in such conditions in solid medium. Violation of these fundamental conditions of mechanics required in determining the physical and mechanical properties of the medium should be taken into account in the integrated interpretations of seismic and laboratory (experimental) data. In this case, application of the linear theory of elasticity and elastic waves does not ensure the reliability of results on the structure and composition of the Earth's core despite compliance with the required integral conditions on the mass, moment of inertia and natural oscillations of the Earth.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2005년도 추계 종합학술대회 논문집
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• pp.219-222
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• 2005

인터넷을 이용한 전자상거래는 시간적, 공간적 한계를 극복할 수 있고, 전세계를 실시간으로 연결하여 하나의 거대한 가상 시장을 제공할 수가 있다. 따라서 인터넷을 통한 여행상품 구매행동 역시 폭발적으로 증가하였다. 이에 난립하여 운영되고 있는 여행사들과 소비자에게 웹상에서 협상 에이전트를 제공하여 소비자에게 원하는 상품을 효율적으로 구매하도록 하여 해당 관광상품에 대한 신뢰성을 증가시키도록 하였다.

• 한국항해항만학회지
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• 제31권5호
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• pp.333-338
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• 2007

본 논문에서는 선박충돌사고의 주요한 원인이 되는 인적운항과실의 감소 및 효과적인 선박충돌회피를 지원하기 위해 새로이 제안된 '속력을 고려한 선박충돌회피지원 모델'을 기반으로 한 선박충돌회피지원 프로그램 개발에 관하여 연구하였다. 이 프로그램은 선행 연구에서 고려되지 않은 상대선박의 속력이 고려되었으며, 자선의 선회특성을 이용하여 상대선박의 침로, 속도에 대한 충돌회피 가능영역과 방법을 표시함으로써, 근접상황에서도 효과적인 충돌회피 조종을 지원할 것이다.

• International Journal of Aeronautical and Space Sciences
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• 제11권4호
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• pp.285-302
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• 2010

Active aeroelastic control is an emerging technology aimed at providing solutions to structural systems that under the action of aerodynamic loads are prone to instability and catastrophic failures, and to oscillations that can yield structural failure by fatigue. The purpose of the aeroelastic control among others is to alleviate and even suppress the vibrations appearing in the flight vehicle subcritical flight regimes, to expand its flight envelope by increasing the flutter speed, and to enhance the post-flutter behavior usually characterized by the presence of limit cycle oscillations. Recently adaptive and robust control strategies have demonstrated their superiority to classical feedback strategies. This review paper discusses the latest development on the topic by the authors. First, the available control techniques with focus on adaptive control schemes are reviewed, then the attention is focused on the advanced single-input and multi-input multi-output adaptive feedback control strategies developed for lifting surfaces operating at subsonic and supersonic flight speeds. A number of concepts involving various adaptive control methodologies, as well as results obtained with such controls are presented. Emphasis is placed on theoretical and numerical results obtained with the various control strategies.

• 보건행정학회지
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• 제27권3호
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• pp.191-198
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• 2017

Moon Jae-in Government announced the Government's 5-Year Plan on July 19, 2017, President Moon directly announced the Government's Plan for Benefit Expansion in National Health Insurance on August 7, 2017. The main contents of the announced expansion include benefit coverage for all medically necessary services with control over non-covered service occurrence, a decrease in the cost-sharing upper limit, and monetary support for catastrophic medical costs. Although past governments have been continuously striving for benefit expansion in the last 15 years, this plan has its breakthrough aspect in that all medical services will be covered by the National Health Insurance. In alignment, there are important tasks to solve: attaining a proper fee schedule, reforming the healthcare delivery system, and improving healthcare quality. This plan is a symptom oriented action in that it is limited in reducing patients' out-of-pocket money, unlike the systematic approach of the National Health Insurance. The sustainability of the National Health Insurance is being threatened due to South Korea's low birth rate, rapidly aging society, and low economic growth, in addition to the unification issue of the Korean Peninsula, medical utilization of the elderly, management of non-communicable diseases, and so on. Therefore, the Government needs to plan the National Health Insurance system reformation including actions addressed toward medical consumers.

• Communications for Statistical Applications and Methods
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• 제25권5호
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• pp.501-512
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• 2018

We propose Sequential Patient Recruitment Monitoring (SPRM), a new monitoring procedure for patient recruitment in a clinical trial. Based on the sequential probability ratio test using improved stopping boundaries by Woodroofe, the method allows for continuous monitoring of the rate of enrollment. It gives an early warning when the recruitment is unlikely to achieve the target enrollment. The packet data approach combined with the Central Limit Theorem makes the method robust to the distribution of the recruitment entry pattern. A straightforward application of the counting process framework can be used to estimate the probability to achieve the target enrollment under the assumption that the current trend continues. The required extension of the recruitment period can also be derived for a given confidence level. SPRM is a new, continuous patient recruitment monitoring tool that provides an opportunity for corrective action in a timely manner. It is suitable for the modern, centralized data management environment and requires minimal effort to maintain. We illustrate this method using real data from two well-known, multicenter, phase III clinical trials.

• Biomolecules & Therapeutics
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• 제14권1호
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• pp.40-44
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• 2006

Mirtazapine is an antidepressant agent with dual action on both the noradrenergic and serotonergic neurotransmitter systems. A simple high performance liquid chromatographic method has been developed and validated for the quantitative determination of mirtazapine in human plasma. A reversed-phase Cl8 column was used for the determination of mirtazapine with a mobile phase composed of 0.01M ammonium acetate solution (pH 4.2) and acetonitrile (75:25, v/v%) at a flow rate of 1.2 mL/min. Terazosin hydrochloride was used as an internal standard. The fluorescence detector was set at excitation and emission wavelengths of 290 and 350 nm, respectively. Intra- and inter-day precision and accuracy were acceptable for all quality control samples including the lower limit of quantification of 3 ng/mL. Mirtazapine was stable in human plasma under various storage conditions. This method was used successfully for a pharmacokinetic study using plasma samples after oral administration of a single 30 mg dose as mirtazapine base to 8 healthy volunteers. The maximum plasma concentration of mirtazapine was $64.1{\pm}28.0ng/mL$ at 1.8 h, and the area under the curve and elimination half-life were calculated to be $674.1{\pm}218.5ng\;h/mL\;and\;23.4{\pm}3.8h$, respectively.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2001년도 추계학술대회
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• pp.65-71
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• 2001

With ever-change and increasingly competitive business environments, firms strive to employ a variety of marketing strategies and execution in order to survive in the market. Such effects would be paid off in the right way only when management of the firms perform marketing activities focusing on long term effectiveness, which would drive company profits up and keep them for long. Demands of customers are being changed and varied. And in this circumstance, it become a main issue of management that the company should produce and sell products according to the customer demands. With these trends, each company has been concentrating effects on generalization of product development technique and distinction of service lot customer In this result with the advantage of mass marketing and database marketing have been drawing attentions from company. Also the internet connected around the world completely diminished the limit of time and distance and company have enveloped keen competition out of each nation and continent in the world market. To fulfill these demands of customer, they need a concept of eCRM(Web based Customer Relationship Management), and go from selling products and services, or gathering customer requests, up to the phase of solving customer's problem by real time or Previous action. With the help of Internet, the frequency and speed of the problem solving has improved greatly.

• 대한조선학회논문집
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• 제36권2호
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• pp.94-104
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• 1999

고장력강을 주로 사용하는 선체에서 좌굴은 중요한 설계기준이 된다. 판부재는 주로 면내강성을 갖는다. 만약 2차좌굴로 인하여 선체판의 면내강성이 저하한다면 선박전체의 종강도는 크게 저하한다. 그러므로, 판부재의 좌굴후거동과 같은 기하학적 비선형거동을 정확히 규명하여야 하는 것은 구조물 전체적으로 매우 필요하다. 이상과 같은 관점에서 본 논문에서는 에너지법을 이용하여 압축하중을 받는 단순지지판의 기하학적 비선형거동을 규명하였다. 에너지 법을 바탕으로 선체판의 탄성대변형해석을 수행하였고 분기점형좌굴과 극한점형좌굴에 대하여 규명하였다.