• 한국통신학회논문지
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• 제37권4A호
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• pp.197-204
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• 2012

본 논문에서는 피드포워드 방식을 이용하여 전력 증폭기의 비선형성 보상과 스마트 안테나 시스템의 경로 결함 보정을 결합하는 새로운 기술을 제안하였다. 배열 안테나의 각각의 경로들이 동일한 특성을 갖도록 하기 위한 보상과 보정을 위해 선형 식에 3차 항을 추가한 다항식과 피드포워드 방식을 사용하였다. 이 방식은 원래의 기저대역 신호를 변형하지 않으므로, 시스템의 기저대역 부와는 독립적인 스마트 안테나 시스템에 적용할 수 있다. 컴퓨터 모의실험을 통하여, 단 하나의 3차 항을 추가함으로써 전력 증폭기의 비선형 효과를 효율적으로 보상하고, 배열 안테나의 각 경로의 선형 결함들 역시 부차적으로 보정할 수 있다.

• 한국의상디자인학회지
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• 제12권4호
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• pp.207-221
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• 2010

This study aim to suggest how alter the korean traditional image design for umbrellas by sublimation transfer digital textile printing. Umbrellas are highly depend on design and made from polyester fiber which is proper item to utilize sublimation transfer digital textile printing. Sublimation transfer digital textile printing system can use computer system to create the delicate high dense images and one full layout through the hole umbrella. It can create distinctive style of design compare with former screen printing umbrella design. As a result of this study, Korean traditional images were adopted and recreated for umbrellas as the modern practical item. 7 of umbrella designs were developed and sample umbrellas could be produced in short period comparing with screen printing process. Through this study, as green printing process, sublimation transfer digital textile printing will be more applied to manufacture high quality textile products along with design development, thus it is expected as an alternative plan to leads growth of umbrella industries.

• 한국물환경학회지
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• 제26권1호
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• pp.133-139
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• 2010

Global human activities associated with the use of fossil fuels have aggravated climate change, increasing air temperature. Consequently, climate change has the potential to alter surface water temperature with significant impacts on biogeochemical cycling and ecosystems in natural water body. In this study, we examined temporal trends on historical records of surface water temperature, and investigated the air temperature/water temperature relationship and the potential water temperature change from an air temperature scenario developed with regional climate model. Although the temporal trends of water temperature are highly variable site-by-site, surface water temperature was highly dependent on air temperature, and has increased significantly in some sub-watersheds over the last two decades. The results presented here demonstrate that water temperature changes are expected to be slightly higher in river system than reservoir systems and more significant during winter than summer for both river and reservoir system. Projected change of surface water temperature will likely increase $1.06^{\circ}C$ for rivers and $0.95^{\circ}C$ for reservoirs during the period 2008 to 2050. Given the potential climatic changes, every $1^{\circ}C$ increase in water temperature could cause dissolved oxygen levels to fall every 0.206 ppm.

• 한국진공학회지
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• 제20권6호
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• pp.387-394
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• 2011

진공펌프의 운전성능을 나타내는 가장 중요한 지표 중의 하나인 배기속도 측정에 관해서는 많은 연구를 통해 정립된 이론에 따라 표준장치와 측정절차에 대한 규격이 만들어지고 널리 활용되고 있다. 그러나 실제 펌프 배기속도 측정 시 이상적인 조건에 비해 변형이 불가피할 때가 있고 그 영향을 간과하면 큰 측정오차를 유발할 수 있다. 본 논문에서는 배기속도를 측정하기 위한 이상적인 또는 실용적인 다양한 방안들이 가지는 물리적 특징과 구조적 오차에 대해 분석하고 보정 식들을 제시했다.

• 경영정보학연구
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• 제9권3호
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• pp.133-156
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• 2007

컴퓨터의 대중적 보급은 아날로그 컨텐츠들의 디지털화를 유도하고 있다. 컨텐츠의 디지털화는 종래의 아날로그 컨텐츠를 위한 미디어 시스템과는 차별화된 디지털 미디어 시스템의 출현을 초래하였다. 종래의 아날로그 미디어와는 달리 디지털 미디어 시스템은 다양한 사용목적과 사용범위를 한 시스템 내에 포괄하고 있다. 본 연구의 목적은 디지털 미디어 시스템 내부에 융합되어 있는 다양한 하위 시스템을 적절하게 표현할 수 있는 디자인 요소를 파악하고 그 효과를 실증적으로 검증하는데 있다. 이를 위해 본 연구에서는 사용자가 미디어에 대하여 갖는 관여도와 동기에 따라 효과적으로 디지털 컨텐츠를 사용할 수 있도록 도와주는 디자인 요소로서 색상차와 색조를 계시하였다. 그리고 색상차와 색조를 이용하여 디지털 미디어 시스템의 프로토타입을 구축하였다. 프로토타입을 이용한 통제된 실험결과 색상차와 색조는 사람들이 시스템에 대해서 느끼는 공간감에 중요한 영향을 미치며, 더 나아가 디지털 미디어 시스템의 사용성에도 유의미한 영향을 미치는 것을 알 수 있었다.

• Toxicological Research
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• 제3권2호
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• pp.97-110
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• 1987

The effects of 5 novel hepatotrophic agents, dithiol malonate derivatives (DMDs; DMD1-DMD5), on the liver microsomal lipid peroxidation induced by carbon tetrachloride $(CCl_4)$ and the correlations with the changes of microsomal electron transport system were investigated. All DMDs were found to inhibit the lipid peroxidation induced by $CCl_4$ in mice and rats as well in vitro liver microsomal system. Therefore, each DMD seemed to have direct mode of action on liver microsomes to inhibit the lipid peroxidation. As an ex vivo study, the induced lipid peroxidation by $CCl_4$ and the changes in electron transport system were determined with liver microsomes obtained from rats chronically treated with DMDs for 7 days. The induced lipid peroxide contents in liver microsomal system were lower in DMD1, DMD2 and DMD3 treated group, but higher in DMD4 and DMD5 group when compared to the control group. Cyt. p.450 contents in the microsomes were decreased by the treatment with DMD1, DMD2 and DMD3, but increased significantly by DMD4 with great extent and by DMD5 with less extent. The cyt. p-450 isozymes induced by treatment of DMD4 and DMD5 were identified as 3-methylcholanthrene (MC) type. The NADPH cyt. -C reductase activities of the microsomes treated with DMD1, DMD2, DMD4 and DMD5 were increased in the range of around 20% to 50%, but decreased with DMD3, All DMDs increased dyt. $-b_5$ content and did not alter NAdH-cyt, $-b_5$ reductase activities in the microsomes. In summary, the 5 novel hepatotrophic agents (DMDs) markedly protected against lipid peroxidation induced by $CCl_4$ in vivo and in vitro possibly through the mechanism of direct action on the liver microsomes. The degree of inhibition produced by DMDs on lipid peroxidation induced by $CCl_4$ seemed to coincide rather with cyt. p-450 contents than with other components of liver microsomal electron transport system including NADPH-cyt, -C reductase.

• 한국전기전자재료학회논문지
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• 제24권1호
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• pp.81-88
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• 2011

A real time monitoring system from a PC has been developed which can be accessed through transmitted data, which incorporates an established low powered transport system equipped with a single chip combined with wireless sensor network technology from a three-axis acceleration sensor. In order to distinguish between static posture and dynamic posture, the extracted parameter from the rapidly transmitted data needs differentiation of movement and activity structures and status for an accurate measurement. When results interpret a static formation, statistics referring to each respective formation, known as the K-mean algorithm is utilized to carry out a determination of detailed positioning, and when results alter towards dynamic activity, fuzzy algorithm (fuzzy categorizer), which is the relationship between speed and ISVM, is used to categorize activity levels into 4 stages. Also, the ISVM is calculated with the instrumented acceleration speed on the running machine according to various speeds and its relationship with kinetic energy goes through correlation analysis. With the evaluation of the proposed system, the accuracy level stands at 100% at a static formation and also a 96.79% accuracy with kinetic energy and we can easily determine the energy consumption through the relationship between ISVM and kinetic energy.

• 생물치료정신의학
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• 제24권3호
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• pp.129-141
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• 2018

Suicide is a behavior that is intended to cause death by itself and requires medical treatment, resulting in suicidal attempt or completion. Suicide causes loss of life, damages the body, costs a lot of medical expenses, and causes families to fall into sorrow and suffering therefore this suicide is a huge loss to family and society. There have been attempts to reduce and prevent suicide by understanding the mechanism of suicide. The mechanism of suicide can be thought of as psychological mechanism and biological mechanism. In the past, if we considered the psychological and biological mechanisms separately, the development of neuroscience now connects and integrates these two. Psychological factors affect biological factors and biological temperaments also affect perception or thinking about the situation and increase psychological vulnerability. Distant factors in suicidal behavior-such as childhood adversity and family and genetic predisposition-increase the lifetime risk of suicide. They alter the response to stress and other processes through changes in gene expression and regulation of emotional and behavioral characteristics. Distant factors affect the biological system and consequently changes in these systems can increase the risk of suicide. In other words, the distal factor does not directly induce suicidal behavior but rather acts indirectly through developmental or mediating factors. These mediating factors are impulsive aggressive and anxious trait, and chronic use of substances. The mechanism of this disorder is the abnormality of the serotonin system and the abnormality of the lipid level. Proximal factors are associated with the onset of suicide events and include changes in the major neurotransmitter systems, inflammatory changes, and dysfunction of glial cells in the brain. A series of studies, including a variety of research methods and postmortem and in-vivo imaging studies, show the impairment of the serotonergic neurotransmitter system and hypothalamic-pituitary-adrenal axis stress response system for suicidal behavior. These disorders lead to suicidal behavior due to difficulty in cognitive control of mood, pessimism, reactive aggression, abnormality in problem solving abilities, excessive response to negative social signals, severe emotional distress, and cognitive dysregulation of suicidal ideation.

• Structural Engineering and Mechanics
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• 제41권6호
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• pp.711-734
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• 2012

The foundation of a tall building frame resting on settable soil mass undergoes differential settlements which alter the forces in the structural members significantly. For tall buildings it is essential to consider seismic forces in analysis. The building frame, foundation and soil mass are considered to act as single integral compatible structural unit. The stress-strain characteristics of the supporting soil play a vital role in the interaction analysis. The resulting differential settlements of the soil mass are responsible for the redistribution of forces in the superstructure. In the present work, the nonlinear interaction analysis of a two-bay ten-storey plane building frame- layered soil system under seismic loading has been carried out using the coupled finite-infinite elements. The frame has been considered to act in linear elastic manner while the soil mass to act as nonlinear elastic manner. The subsoil in reality exists in layered formation and consists of various soil layers having different properties. Each individual soil layer in reality can be considered to behave in nonlinear manner. The nonlinear layered system as a whole will undergo differential settlements. Thus, it becomes essential to study the structural behaviour of a structure resting on such nonlinear composite layered soil system. The nonlinear constitutive hyperbolic soil model available in the literature is adopted to model the nonlinear behaviour of the soil mass. The structural behaviour of the interaction system is investigated as the shear forces and bending moments in superstructure get significantly altered due to differential settlements of the soil mass.

• Molecules and Cells
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• 제44권11호
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• pp.830-842
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• 2021

When perceiving microbe-associated molecular patterns (MAMPs) or plant-derived damage-associated molecular patterns (DAMPs), plants alter their root growth and development by displaying a reduction in the root length and the formation of root hairs and lateral roots. The exogenous application of a MAMP peptide, flg22, was shown to affect root growth by suppressing meristem activity. In addition to MAMPs, the DAMP peptide PEP1 suppresses root growth while also promoting root hair formation. However, the question of whether and how these elicitor peptides affect the development of the vascular system in the root has not been explored. The cellular receptors of PEP1, PEPR1 and PEPR2 are highly expressed in the root vascular system, while the receptors of flg22 (FLS2) and elf18 (EFR) are not. Consistent with the expression patterns of PEP1 receptors, we found that exogenously applied PEP1 has a strong impact on the division of stele cells, leading to a reduction of these cells. We also observed the alteration in the number and organization of cells that differentiate into xylem vessels. These PEP1-mediated developmental changes appear to be linked to the blockage of symplastic connections triggered by PEP1. PEP1 dramatically disrupts the symplastic movement of free green fluorescence protein (GFP) from phloem sieve elements to neighboring cells in the root meristem, leading to the deposition of a high level of callose between cells. Taken together, our first survey of PEP1-mediated vascular tissue development provides new insights into the PEP1 function as a regulator of cellular reprogramming in the Arabidopsis root vascular system.