• 한국전산구조공학회논문집
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• 제13권3호
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• pp.373-384
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• 2000

단기 동 하중(특히 지진하중)을 받는 비선형 강 프레임 구조물의 안전성을 평가하기 위하여 추계론적 유한요소 개념에 근거한 비선형 시간영역 신뢰성 해석 기법을 제안하였다. 제안된 알고리즘에서는 유한요소 공식화가 응답 표면법, 1차 신뢰성 방법, 그리고 반복 선형보간 기법의 개념들과 결합되어 지는데, 이것이 추계론적 유한요소 개념으로 귀결된다. 실제 지진하중의 시간이력이 구조물의 진동을 위해 사용되므로 사실적인 하중조건의 재현이 가능하다. 가상 응력에 기초한 유한요소 기법이 본 알고리즘의 효율성을 증대하기 위해 사용된다. 본 알고리즘은 지진하중 또는 임의의 단기 동적하중을 받는 유한요소 기법으로 표현되는 어떠한 선형 및 비선형 구조물과 관련된 위험도를 평가할 수 있는 잠재성을 가지고 있다. 수치예제를 통하여 알고리즘을 설명하였으며, 몬테카를로 시뮬레이션 기법을 사용하여 본 알고리즘을 검증하였다.

• 디지털융복합연구
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• 제18권6호
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• pp.109-120
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• 2020

디지털화가 수반되지 않는 공급망은 마케팅, 상품개발, 제조, 물류 및 고객에의 상품 인도라는 여러 단계가 서로 독립적으로 수행되는 과정에 불과하다. 디지털화는 이런 여러 단계 간의 벽을 허물고, 모든 이해관계자 집단에게 투명하고 통합된 네트워크로의 변신을 가능하게 한다. 디지털 공급망관리의 최종 목표는 속도와 가시성이다. 이를 목표 달성을 위해서는 다양한 공급망 테크놀러지가 요구되는데, 여기에는 통합계획수립 및 운영체계, 공급망 애널리틱스, 자율적 물류관리, 스마트 물류센터와 스마트 팩토리 등이 포함된다. 이런 기술들은 예상치 못한 운영조건의 변동사항에 대한 가상 시나리오를 구축하고 이에 대한 솔루션을 제공함으로써 공급망 상의 변동에 대응할 수 있는 역량과 예측력을 강화시킨다. 본 연구에서는 공급망의 디지털화에 대한 여러 연구결과를 제시하고 현실적으로 기술도입 과정에서 제기되는 여러 이슈에 대한 논의를 시도해 보고자 한다. 연구결과에 대한 시사점도 함께 제시한다.

• Asian-Australasian Journal of Animal Sciences
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• 제12권1호
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• pp.84-92
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• 1999

The rumen microbial ecosystem is coming to be recognized as a rich alternative source of genes for industrially useful enzymes. Recent advances in biotechnology are enabling development of novel strategies for effective delivery and enhancement of these gene products. One particularly promising avenue for industrial application of rumen enzymes is as feed supplements for nonruminant and ruminant animal diets. Increasing competition in the livestock industry has forced producers to cut costs by adopting new technologies aimed at increasing production efficiency. Cellulases, xylanases, ${\beta}$-glucanases, pectinases, and phytases have been shown to increase the efficiency of feedstuff utilization (e.g., degradation of cellulose, xylan and ${\beta}$-glucan) and to decrease pollutants (e.g., phytic acid). These enzymes enhance the availability of feed components to the animal and eliminate some of their naturally occurring antinutritional effects. In the past, the cost and inconvenience of enzyme production and delivery has hampered widespread application of this promising technology. Over the last decade, however, advances in recombinant DNA technology have significantly improved microbial production systems. Novel strategies for delivery and enhancement of genes and gene products from the rumen include expression of seed proteins, oleosin proteins in canola and transgenic animals secreting digestive enzymes from the pancreas. Thus, the biotechnological framework is in place to achieve substantial improvements in animal production through enzyme supplementation. On the other hand, the rumen ecosystem provides ongoing enrichment and natural selection of microbes adapted to specific conditions, and represents a virtually untapped resource of novel products such as enzymes, detoxificants and antibiotics.

• 대한소아치과학회지
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• 제26권1호
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• pp.146-150
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• 1999

치아발육시기의 항암치료는 치아에 영향을 줄 수 있으며 이에 대한 예상 및 적절한 치료계획수립이 필요하다. 본 증례에서 환자의 왜소치는 항암 화학요법과 관련되어 발생한 것으로 추정되며, 이에 대한 장기적 관찰 및 치료가 필요할 것으로 사료된다.

• 한국환경농학회지
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• 제25권4호
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• pp.371-381
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• 2006

New proteomic techniques have been pioneered extensively in recent years, enabling the high-throughput and systematic analyses of cellular proteins in combination with bioinformatic tools. Furthermore, the development of such novel proteomic techniques facilitates the elucidation of the functions of proteins under stress or disease conditions, resulting in the discovery of biomarkers for responses to environmental stimuli. The ultimate objective of proteomics is targeted toward the entire proteome of life, subcellular localization biochemical activities, and the regulation thereof. Comprehensive analysis strategies of proteomics can be classified into three categories: (i) protein separation via 2-dimensional gel electrophoresis (2-DE) or liquid chromatography (LC), (ii) protein identification via either Edman sequencing or mass spectrometry (MS), and (iii) proteome quantitation. Currently, MS-based proteomics techniques have shifted from qualitative proteome analysis via 2-DE or 2D-LC coupled with off-line matrix assisted laser desorption ionization (MALDI) and on-line electrospray ionization (ESI) MS, respectively, toward quantitative proteome analysis. In vitro quantitative proteomic techniques include differential gel electrophoresis with fluorescence dyes. protein-labeling tagging with isotope-coded affinity tags, and peptide-labeling tagging with isobaric tags for relative and absolute quantitation. In addition, stable isotope-labeled amino acids can be in vivo labeled into live culture cells via metabolic incorporation. MS-based proteomics techniques extend to the detection of the phosphopeptide mapping of biologically crucial proteins, which ale associated with post-translational modification. These complementary proteomic techniques contribute to our current understanding of the manner in which life responds to differing environment.

• Journal of Communications and Networks
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• 제10권3호
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• pp.316-330
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• 2008

This paper proposes a novel method for transporting various types of user traffic effectively over the next generation network called integrated services digital network 3 (ISDN3) (or quantum network) using quantum packets. Basically, a quantum packet comprises one or more 53-byte quanta as generated by a "quantumization" process. While connection-oriented traffic is supported by fixed-size quantum packets each with one quantum to emulate circuit switching, connectionless traffic (e.g., IP packets and active packets) is carried by variable-size quantum packets with multiple quanta to support store-and-forward switching/routing. Our aim is to provide frame-like or datagram-like services while enabling cell-based multiplexing. The quantum packet method also establishes a flexible and extensible framework that caters for future packetization needs while maintaining backward compatibility with ATM. In this paper, we discuss the design of the quantum packet method, including its format, the "quantumization" process, and support for different types of user traffic. We also present an analytical model to evaluate the consumption of network resources (or network costs) when quantum packets are employed to transfer loss-sensitive data using three different approaches: cut-through, store-and-forward and ideal. Close form mathematical expressions are obtained for some situations. In particular, in terms of network cost, we discover two interesting equivalence phenomena for the cut-through and store-and-forward approaches under certain conditions and assumptions. Furthermore, analytical and simulation results are presented to study the system behavior. Our analysis provides valuable insights into the. design of the ISDN3/quantum network.

• 한국환경과학회지
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• 제21권6호
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• pp.725-738
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• 2012

Recently, a variety of GIS-based tools enabling to generate topographic parameters for hydrologic and hydraulic researches have been developed. However, most of GIS-based tools are usually insufficient to estimate and visualize river channel slopes especially along the river network, which can be possibly utilized for many hydraulic equations such as Manning's formula. Many existing GIS-based tools have simply averaged cell-based slopes for the other advanced level of hydrologic units as likely as the mean watershed slope, thus that the river channel slope from the simple approach resulted in the inaccurate channel slope particularly for the mountain region where the slope varies significantly along the downstream direction. The paper aims to provide several more advanced GIS-based methodologies to assess the river channel slopes along the given river network. The developed algorithms were integrated with a newly developed tool named RiverSlope, which adapted theoretical formulas of river hydraulics to calculate channel slopes. For the study area, Han stream in the Jeju island was selected, where the channel slopes have a tendency to rapidly change the upstream near the Halla mountain and sustain the mild slope adjacent to watershed outlet heading for the ocean. The paper compared the simple slope method from the Arc Hydro, with other more complicated methods. The results are discussed to decide better approaches based on the given conditions.

• 대한기계학회논문집A
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• 제34권7호
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• pp.837-842
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• 2010

차량의 유리면에 설치된 와이퍼 시스템은 비나 눈이 올때 운전자의 시야를 확보해주는 중요한 도구이다. 블레이드는 유리면 위의 물체를 닦아내는 가장 중요한 도구이다. 와이퍼 암의 스프링이 블레이드를 유리면 위에 누를 때, 적절한 누름압이 유지되어야 최적의 성능을 얻을 수 있다. 이번 연구에서는 전체 와이퍼 시스템에 대한 동적 해석이 이루어졌다. 상용 구조 동역학 해석 프로그램인 SAMCEF를 이용하여 와이퍼 시스템의 3차원 유한 요소 모델이 생성되었다. 동적 상태에서 블레이드의 누름압의 분포가 계산되었다. 그리고 시뮬레이션 결과를 실험 결과와 비교를 하였다. 이번 연구의 결과를 이용하여 블레이드의 누름압 분포를 예측해 볼 수 있다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권12호
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• pp.5855-5877
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• 2017

In view of personal health and disease management based on cost effective healthcare services, there is a growing need for real-time monitoring services. The electrocardiogram (ECG) signal is one of the most important of health information and real-time monitoring of the ECG can provide an efficient way to cope with emergency situations, as well as assist in everyday health care. In this system, it is essential to continuously collect and transmit large amount of ECG data within a given time and provide maximum user convenience at the same time. When considering limited wireless capacity and unstable channel conditions, appropriate signal processing and transmission techniques such as compression are required. However, ISO/IEEE 11073 standards for interoperability between personal health devices cannot properly support compressed data transmission. Therefore, in the present study, the problems for handling compressed data are specified and new extended agent and manager are proposed to address the problems while maintaining compatibility with existing devices. Extended devices have two PM-stores enabling compression and a novel transmission scheme. A variety of compression techniques can be applied; in this paper, discrete cosine transformation (DCT) is used. And the priority of information after DCT compression enables new transmission techniques for performance improvement. The performance of the compressed signal and the original uncompressed signal transmitted over the noisy channel are compared in terms of percent root mean square difference (PRD) using our simulation results. Our transmission scheme shows a better performance and complies with 11073 standards.

• 대한가정학회지
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• 제48권6호
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• pp.103-118
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• 2010

본 연구는 복지개혁이후 어떻게 저소득층 가정이 그들의 보육요구에 대응하고 있는 가를 질적 접근을 통하여 연구하였다. 본 연구는 연구 초기 생계지원금을 받던 22명의 저소득층 가정의 어머니들을 6개월마다 가정방문 하여 인터뷰를 한 장기적 연구 자료를 토대로 본 연구는 이전 연구에서 잘 다루어지지 않았던 빈곤아동들의 삶을 생애사적 접근으로 조명하였다. 일반적인 보육사용의 흐름, 저소득층 아동이 갖게 되는 보육과 관련된 특별한 조건들에 관한 심층적인 분석과 함께 저소득층 장애아동의 보육과 관련된 요인들도 심층적으로 분석하여 제시하였다. 본 연구의 결과는 공적지원과 더불어 사회적 지원망을 통한 비용부담이 적고 양질의 보육서비스를 제시하는 접근방법이 저소득층 가정의 자생력을 키우는 하나의 좋은 방안이 될 수 있음을 보여주었다.