• East Asian mathematical journal
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• 제25권1호
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• pp.11-26
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• 2009

In this paper, the concepts of compatible mappings of types (A) and (P) are introduced in an induced metric space, two common xed point theorems for two pairs of compatible mappings of types (A) and (P) in an induced complete metric space are established. As their applications, the existence and uniqueness results of common solution for a system of functional equations arising in dynamic programming are discussed.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.418-421
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• 1997

A design method of robust controller for the longitudinal autopilot of BTT missile is considered. The difficulties are a set of linearized dynamic models which corresponds to different operating points has a wide range of parameters and it has even Non-Minimum Phase(NMP) zeros. In this paper, such a family of models is expressed by an interval plant. Then a robust control design method using QFT is represented. A simulation result shows that the proposed controller satisfies the given specification well.

• 한국전자거래학회:학술대회논문집
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• 한국전자거래학회 2000년도 종합학술대회발표논문집
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• pp.179-186
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• 2000

ㆍ A sub-set of SGML (Standard Generalized Markup Language) ㆍ A family of standards ㆍ XML 1.0 is the specification that defines what tags, attributes and other XML nodes are ㆍ License-free, platform-independent and well-supported ㆍ Simple ▶ Human-readable, easy to use ㆍ Extensible ▶ A dynamic data model ㆍ Flexible ▶ For handling complex data ㆍ Portable ▶ For cross-platform data exchange ㆍ Standard ▶ Easy to integrate, widely adopted(omitted)

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.467-468
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• 2008

In this paper, a logic family, the transmission gate CMOS(TG CMOS) is proposed, which combines the transmission gate and pass transistor resulting in a different configuration from traditional full CMOS. In the simulation, basic cells comprising this logic are designed and their dynamic responses are analyzed. The simulation shows their performance is exceeding that of conventional full CMOS.

• 대한족부족관절학회지
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• 제8권1호
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• pp.111-113
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• 2004

In neurogenic equinovarus deformity, surgical intervention such as tendon transfer or osteotomy can be expected to improve symptoms. However, in rare cases of hereditary spastic paraplegia, the deformity and paralysis gradually progress. So limited operation and early post-operative rehabilitation are preferred to aggressive operation. We would like to report our clinical experience with one case of hereditary spastic paraplegia patient with reference review. A 40 year-old male, given tendon transfer of ankle and foot and tendo achilles lengthening 10 years ago, complained about aggravated spastic paraplegia which resulted in dynamic equinovarus and limited walking ability since his operation. Family history showed limited walking ability of his father with gradually progressing spastic paralysis and he was diagnosed as hereditary spastic paraplegia type I. We had performed a limited operation such as tendo achilles and tibialis posterior lengthening to induce plantigrade standing and walking with crutch. As a result, the patient was able to maintain a stabilized standing posture and walk after the operation. Hereditary spastic paraplegia presents with a progressive paralysis which limits rehabilitation after tendon transfer, and the symptoms can be aggravated. Therefore, considering potential hereditary neurogenic disorders in paients with equinovarus deformity and performing limited operative procedures seem to be important.

• Journal of Obesity & Metabolic Syndrome
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• 제27권4호
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• pp.203-212
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• 2018

Dynamic energy balance can give clinicians important answers for why obesity is so resistant to control. When food intake is reduced for weight control, all components of energy expenditure change, including metabolic rate at rest (resting energy expenditure [REE]), metabolic rate of exercise, and adaptive thermogenesis. This means that a change in energy intake influences energy expenditure in a dynamic way. Mechanisms associated with reduction of total energy expenditure following weight loss are likely to be related to decreased body mass and enhanced metabolic efficiency. Reducing calorie intake results in a decrease in body weight, initially with a marked reduction in fat free mass and a decrease in REE, and this change is maintained for several years in a reduced state. Metabolic adaptation, which is not explained by changes in body composition, lasts for more than several years. These are powerful physiological adaptations that induce weight regain. To avoid a typically observed weight-loss and regain trajectory, realistic weight loss goals should be established and maintained for more than 1 year. Using a mathematical model can help clinicians formulate advice about diet control. It is important to emphasize steady efforts for several years to maintain reduced weight over efforts to lose weight. Because obesity is difficult to reverse, clinicians must prioritize obesity prevention. Obesity prevention strategies should have high feasibility, broad population reach, and relatively low cost, especially for young children who have the smallest energy gaps to change.

• 한국멀티미디어학회논문지
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• 제24권1호
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• pp.58-66
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• 2021

The user's password must be encrypted one-way through the hash function and stored in the database. Widely used hash functions such as MD5 and SHA-1 have also been found to have vulnerabilities, and hash functions that are considered safe can also have vulnerabilities over time. Salt enhances password security by adding it before or after the password before putting it to the hash function. In the case of the existing Salt, even if it is randomly assigned to each user, once it is assigned, it is a fixed value in a specific column of the database. If the database is exposed to an attacker, it poses a great threat to password cracking. In this paper, we suggest variable-dynamic Salt that dynamically changes according to the user's password during the login process. The variable-dynamic Salt can further enhance password security during login process by making it difficult to know what the Salt is, even if the database or source code is exposed.

• 한국가정과교육학회지
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• 제28권1호
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• pp.1-17
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• 2016

이 연구의 목적은 중학교 기술 가정교과 '인간발달과 가족' 영역의 핵심개념 '발달'과 '관계'가 2015 개정 가정과 교육과정에서 어떤 의미를 갖는지, 또 중학교 수업현장에서 어떻게 다루어야 하는지를 살펴보는 것이다. 이를 위해 2009 개정 및 2015 개정 교육과정과 13종의 중학교 기술 가정 1, 2 교과서를 분석하였다. 그 결과 첫째, 인간발달과 가족 영역은 2015 개정 교육과정의 핵심역량 중 자기관리 역량, 의사소통 역량, 심리적 감성 역량, 공동체 역량의 함양과 밀접한 관계가 있으며, '발달'에서는 범교과 학습주제 중 인성교육, 안전 건강교육, 인권교육을, '관계'에서는 안전 건강교육, 인성교육, 다문화교육을 효과적으로 다룰 수 있는 것으로 보인다. 둘째, 수업현장의 교수학습과 교재개발 시 고려할 부분은 다음과 같다. 먼저, 핵심개념 '발달'은 전생애적 관점에서의 지속적인 역동성, 신체, 인지, 사회정서발달의 연계성 및 주요개념들의 위계와 체계, 전달정보의 구체성, 경험적 연구결과에 근거한 과학적 정보의 활용, 청소년 발달의 다양성 측면을 충분히 고려해 다루어져야 한다. 다음으로, 핵심개념 '관계'는 세대관계, 성별(젠더)관계, 역할관계, 권력관계라는 가족 집단의 특징을 염두에 두면서, 지식 위주, 정상가족 이데올로기, 중산층 중심의 가족상을 중심의 설명이 되지 않도록 주의해야 한다. 이러한 결과를 바탕으로 핵심개념 '발달'과 '관계'의 추후과제에 대해서 논의하였다.

• Structural Engineering and Mechanics
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• 제39권3호
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• pp.427-447
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• 2011

The progressive collapse phenomenon is generally regarded as dynamic. Due to the impracticality of nonlinear dynamic computations for practitioners, an interest arises for the development of equivalent static pushover procedures. The present paper proposes a methodology to identify such a procedure for sudden column removals, using energetic evaluations to determine the pushover loads to apply. In a dynamic context, equality between the cumulated external and internal works indicates a vanishing kinetic energy. If such a state is reached, the structure is sometimes assumed able to withstand the column removal. Approximations of these works can be estimated using a static computation, leading to an estimate of the displacements at the zero kinetic energy configuration. In comparison with other available procedures based on such criteria, the present contribution identifies loading patterns to associate with the zero-kinetic energy criterion to avoid a single-degree-of-freedom idealisation. A parametric study over a family of regular steel structures of varying sizes uses non-linear dynamic computations to assess the proposed pushover loading pattern for the cases of central and lateral ground floor column failure. The identified quasi-static loading schemes are shown to allow detecting nearly all dynamically detected plastic hinges, so that the various beams are provided with sufficient resistance during the design process. A proper accuracy is obtained for the plastic rotations of the most plastified hinges almost independently of the design parameters (loads, geometry, robustness), indicating that the methodology could be extended to provide estimates of the required ductility for the beams, columns, and beam-column connections.

• 한국과학교육학회지
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• 제40권1호
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• pp.51-60
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• 2020

본 연구에서는 문헌 고찰을 기반으로 현상학적 접근 및 NOS-가족 유사성 접근을 적용하여 지구과학의 본성을 규명하는 방법을 제안하였다. 현상학적 접근은 지구과학에 고정된 본질이 있는 것이 아니라 시대와 상황의 요청에 따라 본성 자체가 유동적인 것임을 전제로 한다. 이는 직관적으로 드러난 감각적 현상들을 통해 지구과학의 다면적 특성을 편견 없이 모두 수집, 분석하고 종합하는 방법이다. 현상학적 접근은 학문적 세계의 토대를 이루는 생활세계를 직시하면서 지구과학의 본성을 탐구할 수 있는 통찰력을 제공한다. 이를 통해, 지구과학이 가지는 풍부함과 복잡성, 역동성을 드러낼 수 있다. 현상학적 관점에서 지구과학의 본성을 탐색하기 위한 방법으로, 과학의 본성(NOS)에 대한 가족유사성 접근을 제안하였다. NOS-가족유사성 접근을 통해, 조금씩 차이점을 가지는 다양한 과학의 영역들이 서로서로 공유하는 특성들을 조합함으로써 과학의 본성(NOS)을 포괄적으로 설명할 수 있다. 이를 지구과학의 본성에 적용하면 지구과학을 '가족'으로 만들어주는 일반적인(domain-general) 특성과 영역별로 특수한(domain-specific) 특성을 동시에 규명할 수 있다. 예컨대 지구과학을 구성하는 학문영역인 지질학, 대기 과학, 해양학, 천문학, 지구시스템 과학 등등이 서로 공유하는 특징들의 네트워킹을 통해 이들 학문영역을 지구과학이라는 가족으로 특징짓는 가족유사성을 추출할 수 있고, 이를 통해 지구과학의 본성을 총체적으로 드러낼 수 있을 것이다. 또한, 지구과학의 본성에 대한 가족유사성 접근을 통해 지구과학을 구성하는 하위 영역 학문의 특성이 달라짐에 따라 변화하는 지구과학의 본성을 파악할 수 있으며, 교과목으로서 지구과학의 위상과 발전체계를 정립하는 데에도 기여할 수 있을 것이다.