• 한국결정학회지
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• 제13권3_4호
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• pp.158-164
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• 2002

Tetrahomodioxa p-phenylcalix(4)arene dihexylether (C/sub 66/H/sub 68/O/sub 6/)를 합성하여 분자 및 결정 구조를 X-선 회절법으로 연구하였다. p-Phenylphenol의 탈수, 고리화 반응으로 만든 tetrahomodioxa p-phenylcalix(4)arene을 DMF에서 NaH와 hexyl iodide를 환류시켜 합성하였다. 결정은 사방정계이고 공간군은 P2₁2₁2₁, a =9.764(2), b = 16.167(2), c = 32.994(3) Å, V=5208(1) ų, Z= 4, Dc=1.221 gcm/sup -3/이다. 직접법으로 구조를 해석하였으며, 최소자승법으로 정밀화하여 최종 신뢰도 R 값은 2009개의 회절 반점에 대해 0.070 이었다. 이 분자는 마주 보고 있는 phenyl group 두 쌍이 거의 평행을 이루며, C-1,2-alternate conformation이고, lower rim의 1,3 위치에 hexyl 기가 치환된 비대칭 homooxacalixarene이다.

• 폴리머
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• 제27권6호
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• pp.549-554
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• 2003

톨루엔, 자일렌 등 유기 용매에 녹는 에머랄딘 염 형태의 폴리아닐린-도데실벤젠술폰산 (PANI-DBSA) 이 한 단계 마이셀 유화 중합법에 의해 제조되었다. 유기 양성자산으로 DBSA가 사용되었으며, DBSA와 아닐린 단량체의 비율이 1.5:1의 중합 조건에서 용해도 및 전기적 특성이 가장 우수하였고, 이때 제조한 PANI-DBSA의 톨루엔에서 용해도는 8 wt% 정도이다. 이들은 유리 또는 플라스틱 필름 기판 위에 도포되어 필름 형상으로 얻어지며, 폴리우레탄 또는 폴리스티렌 등과도 쉽게 혼합되었다. 5 S/cm 이상의 전기 전도도와 500 nm 이하의 필름두께에서 70% 이상의 가시광선 투과도를 보이며, 필름의 표면상태가 수용액에서의 유화 중합법에 의해 제조되는 PANl-DBSA보다 매우 균일함을 AEM을 통해 관찰하였다. 반응생성물의 대부분은 톨루엔 용매에 용해되었지만 용해되지 않은 일부 PANI-DBSA은 50-400 nm크기의 입자로 유기 용매에 분산되어 있음이 확인되었고 이들 입자의 결정상태를 XRD를 통해 관찰하였다.

• 한국축산식품학회지
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• 제35권5호
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• pp.707-713
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• 2015

Royal jelly has been widely used as a health supplement worldwide. However, royal jelly has been implicated in allergic reactions, and we developed a water-soluble royal jelly (WSRJ) without the allergy inducing protein. In this study, we aimed to identify the anti-melanogenic efficacy of WSRJ. B16F1 melanoma cells were first treated with 10 nM α-melanocyte stimulating hormone (α-MSH) and then with various doses of WSRJ. In addition, we investigated the mRNA and protein expression of melanogenesis-related genes such as tyrosinase, tyrosinase related protein-1 (TRP-1) and TRP-2 by reverse transcription-polymerase chain reaction and western blotting. WSRJ directly inhibited tyrosinase and cellular tyrosinase activity, which decreased melanin synthesis in α-MSH stimulated B16F1 melanoma cells a level comparable to that observed with arbutin. WSRJ decreased the mRNA and protein expressions of tyrosinase, TRP-1, and TRP-2, which was comparable to that observed with arbutin. WSRJ has strong anti-melanogenic activity, which invoice direct inhibition of tyrosinase enzyme activity and suppression of expression of melanogenesis related genes. Results from this study suggests that WSRJ is a potential candidate for the treatment of skin pigmentation.

• 한국광물학회지
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• 제23권3호
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• pp.191-197
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• 2010

고순도 니켈 금속염으로부터 미세하고 입도가 균일한 니켈 분말 직접 제조 연구를 수행하였다. 구형의 형상을 갖는 미세한 니켈 분말을 제조하기 위하여 입도제어가 가능한 슬러리환원법을 사용하였다. 제조된 니켈 분말에 화학성분, 입도, X선회절, 주사전자현미경 분석을 실시하여 니켈 분말의 특성을 조사하였다. 환원제로 하이드라진(hydrazine)을 사용하고, 4.5 M NaOH에서 90분 반응시켜 약 100~200 nm의 입도를 가진 분산도가 양호한 구형의 니켈 분말을 제조할 수 있었다.

• International journal of advanced smart convergence
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• 제5권4호
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• pp.15-20
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• 2016

When a virtual sound source for 3D auditory system is reproduced by a linear loudspeaker array, listeners can perceive not only the direction of the source, but also its distance. Control over perceived distance has often been implemented via the adjustment of various acoustic parameters, such as loudness, spectrum change, and the direct-to-reverberant energy ratio; however, there is a neglected yet powerful cue to the distance of a nearby virtual sound source that can be manipulated for sources that are positioned away from the listener's median plane. This paper address the problem of generating binaural signals for moving sources in closed or in open environments. The proposed perceptual enhancement algorithm composed of three main parts is developed: propagation, reverberation and the effect of the head, torso and pinna. For propagation the effect of attenuation due to distance and molecular air-absorption is considered. Related to the interaction of sounds with the environment, especially in closed environments is reverberation. The effects of the head, torso and pinna on signals that arrive at the listener are also objectives of the consideration. The set of HRTF that have been used to simulate the virtual sound source environment for 3D auditory system. Special attention has been given to the modelling and interpolation of HRTFs for the generation of new transfer functions and definition of trajectories, definition of closed environment, etc. also be considered for their inclusion in the program to achieve realistic binaural renderings. The evaluation is implemented in MATLAB.

• 대한간호학회지
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• 제50권4호
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• pp.513-522
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• 2020

Purpose: This study aimed to utilize concept analysis to obtain a better understanding of the concept of "continuity of care" in chronic diseases. Methods: The concept of continuity of care was analyzed using the Walker and Avant method. Covering literature in English from 1930 to 2018, the data sources included CINAHL Complete, Academic Search Complete, MEDLINE, PsyARTICLES, Health Source: Nursing/Academic Edition, Google Scholar, Science Direct, and the Cochrane Library. Results: A comprehensive definition of concept of continuity of care was developed based on a systematic search and synthesis. The key defining attributes were identified as (a) care over time, (b) the relationship between an individual patient and a care team, (c) information transfer, (d) coordination, and (e) meeting changing needs. The antecedents of continuity of care were having a chronic disease, inexperienced with disease management, a poorly coordinated healthcare system, and medical care limitations. The consequences of continuity of care were decreasing hospital admissions, reducing costs, reducing emergency room visits, improving the quality of life, improving patient satisfaction, and delivering good healthcare. Conclusion: The thorough concept analysis provides insight into the nature of "continuity of care" in chronic diseases and also helps ground the concept in healthcare.

• Journal of Periodontal and Implant Science
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• 제26권2호
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• pp.376-395
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• 1996

The neuropeptide substance P(SP) has been recognized to modulate immune systems, with close proximity between peptidergic sensory nerve endings and immune cells. These include the macrophage and neutrophil activation, IL-2 production in T cell, augmentation of Ig synthesis, mast cell degranulation, $PGE_2$ and collagenase secretion in synoviocytes. In this study I examined SP-induced various biological activities such as antimicrobial action, cytokine production, and mast cell degranulation in the presence or absence of other inflammatory cell activators. Antimicrobial studies showed that undifferentiated HL-60 cells were not affected by SP. However, SP significantly enhanced antimicrobial action of TPA-treated or dbcAMP-treated HL-60 cells which had been differentiated into PMN or macrophage/monocyte. I could not find synergistic relationship between SP and LPS in parallel experiments of the above. SP did not induce IL-l production from murine macrophage cell line RAW264.7 whether costimulated with LPS or not. Mast cell degranulation was occured only when stimulated with high dose ($10^{-5}M$) of SP and the degree of this activation was slightly reduced by simultaneous application of $MIP-1{\alpha}$. In addition, CGRP which is known to be a common coexisting neuropeptide with SP within specific fibers did not augment the function of SP on mast cell degranulation. These results suggest that immunoregulatory activities of SP could be mediated through direct upregulation of various functions of immune cells and also upregulation of responsiveness of immune cells to other immune activators.

• 한국정보통신학회논문지
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• 제14권12호
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• pp.2628-2635
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• 2010

본 논문에서는 차량용 FMCW(Frequency Modulated Continuous Wave) 레이더의 도플러 주파수와 아날로그-디지털 변환기 비트 수에 따른 탐지 성능 분석 및 신호처리부 개발을 진행하고자 한다. 성능 평가를 위한 FMCW 레이더의 시스템 모델은 송신부와 수신부로 구성되어 있으며 채널은 가우시안 잡음 환경을 사용한다. 이론과 시뮬레이션을 통해서 시스템 모델을 검증한다. 수신부에서는 수신 신호와 기준 신호사이의 부정합으로 인한 주파수 오차가 발생하게 된다. 75cm의 분해능를 갖는 FMCW 레이더에서 도플러 주파수가 약 38KHz이하인 경우 탐지 성능의 열화가 발생하지 않음을 알 수 있다. 아날로그-디지털 변환기 비트에 따른 탐지 성능은 6비트가 최소의 비트로 결정될 수 있음을 알 수 있다. 그리고 FPGA를 이용하여 디지털 송신 파형 발생기를 위한 집적 디지털 신디사이저(Direct Digital Synthesis) 칩을 기반한 FMCW 레이더 신호처리부를 설계 및 구현을 진행한다.

• 한국실내디자인학회논문집
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• 제26권6호
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• pp.13-23
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• 2017

The purpose of this study is to analyze the expression method according to the planning of townhouse and the healing method that affects residents for communicating with natural environment, in order to propose resident-focused communication with nature for healing. The results are as follows. First, the expression of nature elements can be divided into 'direct' and 'indirect' and healing effects through nature can be divided into 'body' and 'psychology'. The healing method of residents through nature was classified into physical and psychological healing through openness, familiarity, comfort, and stability. Second, as an expression method according to townhouse planning, the arrangement plan induced active communication with nature through the arrangement according to topography and a common garden. In terms of construction plan, a bigger window or door than that of other residential spaces was installed on a wall, ceiling or opening to directly bring the nature of outside visually for more communication. Third, with regard to healing methods of townhouse, 'openness' which reduces depression and increases self-esteem, expands the view of residents. 'Familiarity', the healing method that can relieve the fatigue of eyes and bring psychological warmth and comfort, makes us feel familiar through the pattern and texture of woods and stones that are natural materials. 'Comfort' which heals residents by creating an outside space and bringing the nature elements through a huge window can provide psychological healing such as eased tension in daily life as well as physical healing such as vitamin D synthesis and the recovery of physiological function. Also, 'Stability' gives a comfortable feeling by applying the colors of finishing materials inside or seeing the colors of surrounding nature as it is through big windows. Finally, in order to support the results of this study more objectively, a follow-up study conducting a survey on the residents of townhouse is needed.

• Journal of Advanced Marine Engineering and Technology
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• 제40권10호
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• pp.894-898
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• 2016

Solution plasma is a unique method which provides a direct discharge in solutions. It is one of the promising techniques for various applications including the synthesis of metallic/non-metallic nanomaterials, decomposition of organic compounds, and the removal of microorganism. In the context of nanomaterial syntheses, solution plasma has been utilized to produce carbon nanoparticles and metallic-carbon nanoparticle systems. The main purpose of this study was to synthesize nickel nanoparticles embedded in a matrix of carbon particles by solution plasma in one-step using waste vegetable oil as the carbon source. The experimental setup was done by simply connecting a bipolar pulsed power generator to nickel electrodes, which were submerged in the waste vegetable oil. Black powders of the nickel nanoparticles-embedded carbon (NiNPs/Carbon) particles were successfully obtained after discharging for 90 min. The morphology of the synthesized NiNPs/Carbon was investigated by a scanning electron microscope, which revealed a good dispersion of NiNPs in the carbon-particle matrix. The X-ray diffraction of NiNPs/Carbon clearly showed the co-existence of crystalline Ni nanostructures and amorphous carbon. The crystallite size of NiNPs (through the Ni (111) diffraction plane), as calculated by the Scherrer equation was found to be 64 nm. In addition, the catalytic activity of NiNPs/Carbon was evaluated by cyclic voltammetry in an acid solution. It was found that NiNPs/Carbon did not show a significant catalytic activity in the acid solution. Although this work might not be helpful in enhancing the activity of the fuel cell catalysts, it is expected to find application in other processes such as the CO conversion (by oxidation) and cyclization of organic compounds.