• Carbon letters
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• 제12권2호
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• pp.107-111
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• 2011

Polyacrylonitrile (PAN) fibers were pre-oxidized in a temperature range of 180-275$^{\circ}C$. The effects of positive and negative stretching on the structure and morphology of PAN fiber in the pre-oxidation process were studied by FTIR spectroscopy, XRD, and SEM. Mechanical property changes were also investigated. No changes in the movement and intensity of functional groups of PAN fibers were caused by positive stretching of up to 10% and negative stretching down to -8%. The crystal structure can be affected by the positive stretching and negative stretching. The maximum strength is 479.81 MPa when the stretching is positive, and the maximum strength is 420.55 MPa when the stretching is negative.

• 한국전문물리치료학회지
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• 제26권4호
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• pp.63-69
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• 2019

Background: Both the rapid concentric and eccentric contractions during exercise repeatedly impose excessive stress on muscle tissue. The hamstring muscles are very susceptible to injury due to the tensile stress. Various interventions are currently being undertaken to prevent strain injury before exercise. Stretching is the most common method and is known to have a positive effect on flexibility and muscle performance. However, relatively few studies have investigated the potential negative factors of stretching. Objects: The purpose of this study was to examine changes in pain following the different intensity of the stretching and types of physical stress. Methods: The subjects were divided into three groups based on the intensity of stretching: 100% (S100), 75% (S75), and 50% (S50) of the measured force at the point of discomfort in static stretching and 100% (P100), 75% (P75), and 50% (P50) of the maximum voluntary isometric contraction in Proprioceptive Neuromuscular Facilitation (PNF) stretching. The pain individual subjects perceived after stretching was measured via a Visual Analog Scale (VAS) and compared between the groups Results: Despite the decrease in the intensity of static stretching, no decrease in VAS value was observed. In PNF stretching, a significant decrease was observed at P50 compared to P100. S100 was significantly higher than P75 and P50. Conclusion: Previous studies have shown that PNF has a superior or the same effect on flexibility in comparison with static stretching. This effect was maintained even in moderate intensity. PNF stretching performed under moderate rather than high intensive static stretching, which causes pain and discomfort, might be recommended in clinical settings.

• 대한물리의학회지
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• 제17권3호
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• pp.79-86
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• 2022

PURPOSE: By virtue of its location, the iliopsoas muscle has the potential to affect the function of the diaphragm. Therefore, the purpose of this study was to investigate the effects of passive stretching of the iliopsoas muscles on pulmonary function. METHODS: Twenty male university students participated in this study. Subjects with low back pain, negative results on the modified Thomas test, and chest breathing patterns not directly related to the function of the iliopsoas muscles were excluded from this study. A digital pulmonary function measuring device (Pony FX, COSMED Inc, Italy) was used to test pulmonary function. The test was performed three times: the first test before passive stretching, the second test 10 minutes after the first test, and the third after passive stretching. Passive stretching was performed 5 times for each of the left and right iliopsoas muscles. Passive stretching was carried out for 20 seconds followed by a 10-second break. The SPSSWIN (ver. 27.0) statistics program was used for data analysis, and the significance level was α =.05. RESULTS: Among slow vital capacity (SVC) parameters, tidal volume (VT), inspiratory reserve volume (IRV), inspiratory capacity (IC) and vital capacity (VC) improved significantly after passive stretching. Also, among the maximal effort vital capacity (MEVC) parameters, forced vital capacity(FVC) and forced expiratory volume in one second(FEV1) improved significantly after passive stretching. CONCLUSION: The results showed that among the various pulmonary function parameters measured, passive stretching of the iliopsoas muscles can improve the SVC and MEVC. Therefore, passive stretching of the iliopsoas muscles may be considered for use as a treatment method to improve pulmonary function.

• 한국융합학회논문지
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• 제11권1호
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• pp.285-291
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• 2020

오늘날 현대 여성들은 여성성을 가장 극대화할 수 있는 가슴 성형에 대한 여성들의 관심은 더욱 커지고 있다. 그러나 유방 확대술은 부작용에 대한 논란이 지속되고 있으며 많은 사람들이 두려워하고 있는 수술 중의 하나이다. 이러한 부분을 보완하고자 본 연구는 한국여성 23명을 대상으로 E사의 비수술적인 유방 확대 프로그램인 가슴 스트레칭 기기를 10주동안 사용하여 가슴이 형태적 변화를 연구하였다. 실험 결과로 체중의 변화는 없었으나 가슴의 컵 사이즈 확대, 유방 직경 증가, 유방 부피가 증가하였으며 가슴 탄력의 변화는 거의 없는 것으로 확인되었다. 가슴 외부 연부조직 확장 시스템이 동양인 한국 여성에게 가슴의 형태적 변화에 도움이 되는 것으로 확인되었다. 그러나 이 시스템은 일정 기간 사용 시간을 준수하기 위해 사회적인 생활에 제약을 받을 수 있으며 개인적인 노력이 뒷받침되어야 한다.

• 한국실내디자인학회논문집
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• 제20권6호
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• pp.173-182
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• 2011

These days, Emotional Design is on the sustainable development through activity study thogh, until now, the study proceed too far with Sensibility Ergonomics applied to SD. However, on this paper, the study would be make progress through GSD that it applied to Verb. For this reason, applied to Emotional Design consideration of theory through JOAN MEYERS-LEVY's papaer titled "The Influence of Ceiling Height", Laban Movement Analysis and Aspect of Semiotics and then judgement of GSD would be make progress through experiment to collection of Emotional Vocabularies and evaluation of body movement. There is a method of analysis by using statistical program such as SPSS 18.0 and it would have validity of analysis. Here is a result of this study. According to heights of ceiling types(2.4M, 3.0M) there are differences between behavior of Figure Attachment, Emotional Vocabularies of the event and Body Movement. While the Figure Attachment has a tendency to restricted scope, CH has a tendency to make attachment within the scope. You could see the Negative Adjective for Emotional Vocabularies at CL and the Positive Adjective ranges at the CH. Basic body movement for passive, 'moving' and 'stretching' as shown at CL more than the CH. For active movement which has purpose, 'moving the weight' and 'stretching' as shown at CH more than at CL.

• Journal of Microbiology and Biotechnology
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• 제22권5호
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• pp.614-621
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• 2012

Silver nanoparticles production by the green chemistry approach was investigated using an isolated marine actinomycetes strain. The isolated strain was identified as Streptomyces albidoflavus based on chemotaxonomic and ribotyping properties. The strain revealed production of silver nanoparticles both extracellular and intracellularly. Surface Plasmon Resonance analysis with the function of time revealed that particle synthesis by this strain is reaction time dependent. The produced particles were spherical shaped and monodispersive in nature and showed a single surface plasmon resonance peak at 410 nm. Size distribution histograms indicated production of 10-40-nm-size nanoparticles with a mean size of 14.5 nm. FT-IR spectra of nanopartilces showed N-H, C-H, and C-N stretching vibrations, denoting the presence of amino acid/peptide compounds on the surface of silver nanoparticles produced by S. albidoflavus. Synthesized nanoparticles revealed a mean negative zeta potential and electrophoretic mobility of -8.5 mV and -0.000066 $cm^2/Vs$, respectively. The nanoparticles produced were proteinaceous compounds as capping agents with -8.5 mV zeta potential and revealed antimicrobial activity against both Gram-negative and -positive bacterial strains. Owing to their small size, these particles have greater impact on industrial application spectra.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.415-420
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• 2009

Selective Catalytic Reduction(SCR) has been used for the reduction of $NO_x$ in a steam supply boiler. Recently, the reduction of $NO_x$ becomes an important research field because of its negative effect on an environment. Shape optimization of circular poles installed in the chamber, which is located in upstream of a SCR, has been performed using response surface method and three-dimensional Navier-Stokes analysis to enhance gas flow uniformity. Three design parameters, diameter, arranging angle and stretching ratio of circular poles, are considered in the present study. Throughout the shape optimization of a circular pole, gas flow uniformity is successfully increased by decreasing local recirculation flow in a square duct chamber. Recirculation flow observed in the corner of the square duct can be reduced by proper installation of a guide vane or a blunt body. Detailed flow characteristics are also analyzed and discussed.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 춘계학술대회 논문집
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• pp.195-198
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• 2009

In this study, in order to get the forming limit of AHSS sheet in the negative minor strain region, the shapes of die corner and drawbead are redesigned by employing the Taguchi's design of experiment method and the FEM forming simulation. With the redesigned FLD tool, the forming limit tests of automotive multi-phase(Dual Phase and Complex Phase) steel sheets which induce the normal fractures on the blank are performed.

• Bulletin of the Korean Chemical Society
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• 제23권10호
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• pp.1404-1408
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• 2002

The resonance Raman spectra of trans-polyacetylene films doped heavily with electron donor (Na) and acceptor (HClO4) have been measured with excitation wavelengths between 488- and 1320-nm, and the relationships between the Raman excitation photon energies (2.54-0.94 eV) and its wavenumbers were discussed. We found the linear dependence of the Raman shifts with the exchanges of excitation photon energies. In particular, the Raman wavenumbers in the C=C stretching $(V_1$ band) showed a dramatic decrease with the increase in Raman excitation photon energies. In the case of acceptor doping, its change is larger than that of donor doping. The observed wavenumber (1255-1267 $cm^{-1}$) of the $V_2$ band (CC stretch) of Na-doped form is lower than that of the corresponding band (1290-1292 $cm^{-1}$) of its pristine trans-polyacetylene, whereas the contrary is the case for the HClO4 doped form (1295-1300 $cm^{-1}$). The origin of doping-induced Raman bands is discussed in terms of negative and positive polarons.

• 한국중재학회지:중재연구
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• 제31권3호
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• pp.91-107
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• 2021

The Korean Association of Arbitration Studies faces its 30th anniversary in 2020 since its foundation in 1991 and is being celebrated and congratulated across the communities in and out of the country. However, the association seems to be standing at crossroads between a negative and positive direction. As shown in the past KAAS pattern in its academic activities, the academic community tends to focus relatively more on domestic issues, expanding its domestic network rather than international network for the past years. KAAS needs to turn its face to see the other side of the world, stretching its hands to the people outside first. For this purpose, this paper suggests that KAAS should strengthen its cooperative capability through the international cooperation division. KAAS' past 30 years of accumulated know-how and its academic network will play critical roles i-n expanding its partners across the global academic community. This paper delivers special thanks to the institutions, including the LMAA, CAC, SIAC, HKIAC, RSPP/ACRU, IDAC, and LAMC who sent cooperative works and congratulatory messages to KAAS 30th anniversary despite the COVID-19 pandemic situation.