• Applied Microscopy
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• v.19 no.1
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• pp.70-88
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• 1989

The storage sac of U. unicinctus can be divided into two parts morphologically as well as functionally ; one is proximal and the other distal storage sac. It is because of the seasonal morphological change of the storage sac caused by sperm accumulation in the storage sac. The proximal storage sac contains the mature sperm with the dumbbell-shaped acrosome and well developed one or two mitochondria in the middle piece, whilst the sperm of hemispherical acrosome associate closely with an accessory cell in the distal storage sac. This means that the sperm do not perform the synchronous development in a storage sac, which is not the case of sperm development in the coelomic cytophorus. In addition, the basal membrane of the distal storage sac is different from that of the proximal storage sac in term of tissue formation. Connective tissues, acces-sory cells and small lumen develop on the basal membrane of the distal sto-rage sac, which is well contrasted with the thin basal membrane of the proximal storage sac. The function of the storage sac is discussed in rela-tion of the sperm development and the seasonal change.

• Journal of the Korean institute of surface engineering
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• v.31 no.6
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• pp.359-370
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• 1998

TiAl-based intermetallic compounds were electro-bornizel in the mixture of $Na_2B_4O_7$, KCL and LiCl in the termetature rage between 850 and $1000^{\circ}C$for various times (1-5 hours)under the fixed current density of 0.5 A/$cm^2$. The optimized composition of electrolyte in this work was decided to be 76.9 wt% $Na_2B_4O_7$-19.2 wt.%(0.7KCl-0.3LiCl) -3.9 wt.% al. The samples with boronized layer were investigated by SEM, XRD and EDS. The surface micro-hardness of boronized TiAl was also evaluated using Micro Vickers Hardness Tester. The sample, boronized at $900^{\circ}C$ for 4 hours in the above composition of electrolyte under the current density of 0.5 A/$\textrm{cm}^2$, has about 36$\mu\textrm{m}$ think layer on the surface, and its surface micro-hardness was measured to be 1263 Hv. From the results of SEM, XRD and EDS, the layer consisted of $TiB_2$ sublayer and Al-oxide sub layer. Al-depleted layer below the Al-oxide sudlayer was also detected. The activation energy for formation of boronized layer in this study was calculated as 178 Kcal/moleK.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.3
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• pp.677-684
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• 2018

Recently, negative emotional responses by drivers are a growing problem, which leads to not only a traffic accident but a crime so called 'road rage' in countries with heavy traffics including South Korea. Under such a circumstance, measuring stress- and fatigue-induced emotional responses by means of wireless communication and a wearable system would be useful. The purpose of this study is to implement a system that measures various signals from a driver, derives and monitors his emotional responses from the measurements and verify its derivations with reliability. This paper, as a first part of the research, describes how the system has been implemented with experimental methods.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1479-1482
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• 2006

본 연구는 우리나라 강수자료 중 90년 이상의 자료를 보유한 지점(서울, 인천, 목포, 부산)에 대해서 변화도 분석과 Singular Spectrum Analysis(SSA)를 사용하여 자료의 주성분 및 주기성을 분석하였다. 각 자료의 변화도 분석결과 1907에서 2004년까지 98년간의 장기변화 중 선형추세에 의한 강우변화량은 23-11mm/mon 증가한다. 선형추세에 의한 년 강우변화량은 276-132mm/yr 이며 증분의 약 65%가 8월 증가량으로 과거 30년 강우분포는 7월에만 피크를 가지나 최근 30년의 강우분포는 7월과 8월에 비슷한 피크를 가지는 변화를 보일 뿐 아니라 지역에 따라 상이한 분포 양상을 보였다. 강우의 선형적 증가와 함께 변화폭도 증가하며 서울, 인천지역이 목포, 부산지역보다 큰 증가 양상을 보였다. 월 변화패턴과 선형추세 등 확정적 변화를 제거한 anomaly는 장기 변동과 각 달에 대해 다른 변동 폭을 가지는 noise의 합의 형태로 나타난다. Moving ave rage를 이용한 장기변동양상은 특정 주기를 가지지 않을 뿐만 아니라 변동 폭도 noise의 변동 폭에 비하여 미소하다. SSA결과 첫 번째 주성분이 전체변화의 1.7%이며 30번째 성분은 전체변화의 약 1% 정도로 장주기의 변화를 보였으나 전체자료에 비해 각 요소들이 설명하는 비중이 상당히 낮았다.

• The Journal of Korean Physical Therapy
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• v.17 no.2
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• pp.38-45
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• 2005

This study was deigned to identify the effect of electromyographic activity of knee extensor during contralateral hip isometric adduction. six young adults who had not experienced any knee injuries were recruited. Their Q-angles were within a normal rage. They were asked to sit on the table. The EMG activities of the vastus lateralis (VL), vastus medialis oblique (VMO) were recorded in sitting by surface electrodes and normalized by MVC EMG values derived from manual muscle test. The EMG activity levels of the VL, RF, and VMO were the highest when foot was externally rotated. The EMG activity level of VMO/VL ratio did show significant differences(p<.05). The onset time of vastus lateralis (VL) and vastus medialis oblique (VMO) was similar in contralateral hip isometric adduction(p<.05).

• Journal of the Korean Society of Safety
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• v.30 no.2
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• pp.83-89
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• 2015

In Korea for 20 years(1993-2012), total number and average annual number of oil spills were 6,608 cases and total volume and average annual volume of oils spilt were $57,328k{\ell}$ and nearly $2,866k{\ell}/year$, respectively. The annual number of oil spills and annual amount of oil spilt tended to decrease with the lapse of year in Korea. As oil transportation worldwide continues to increase, many communities are at risk of oil spill disasters and must anticipate and prepare for them. Factors that influence oil spill consequences are myriad and rage from the biophysical to the social. In this paper, we analysed the emergency response systems and recovery apparatuses for oil spill accident in marine and proposed a developed oil diffusion apparatus which can be used to initial response stage by crew, and to extend golden times. This system can be minimized casualties for rescued people in disaster.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.279-282
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• 2011

Projectile can be damaged during the storage and handling. Maximum range calculation of the ammunition was performed on the assumption that each projectiles have 1.5mm/3.3mm axisymetric dent on the surface. Drag coefficient for trajectory calculation was delivered from CFD using commercial software FLUENT. In the result of CFD, damaged projectiles those have 1.5mm/3.3mm axisymetric dent have similar drag coefficient compare with normal projectile in the region of subsonic. But, in supersonic region, drag coefficient was increased 3%, 9% each in average. In the result of trajectory calculation, Maximum rage was decreased 1%, 3% each.

• The Journal of Korea Robotics Society
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• v.4 no.4
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• pp.257-264
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• 2009

This paper proposes a novel face detection method that finds tiny faces located at a long range even with low-resolution input images captured by a mobile robot. The proposed approach can locate extremely small-sized face regions of $12{\times}12$ pixels. We solve a tiny face detection problem by organizing a system that consists of multiple detectors including a mean-shift color tracker, short- and long-rage face detectors, and an omega shape detector. The proposed method adopts the long-range face detector that is well trained enough to detect tiny faces at a long range, and limiting its operation to only within a search region that is automatically determined by the mean-shift color tracker and the omega shape detector. By focusing on limiting the face search region as much as possible, the proposed method can accurately detect tiny faces at a long distance even with a low-resolution image, and decrease false positives sharply. According to the experimental results on realistic databases, the performance of the proposed approach is at a sufficiently practical level for various robot applications such as face recognition of non-cooperative users, human-following, and gesture recognition for long-range interaction.

• The Korean Journal of Physiology and Pharmacology
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• v.18 no.1
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• pp.1-14
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• 2014

During long standing hyperglycaemic state in diabetes mellitus, glucose forms covalent adducts with the plasma proteins through a non-enzymatic process known as glycation. Protein glycation and formation of advanced glycation end products (AGEs) play an important role in the pathogenesis of diabetic complications like retinopathy, nephropathy, neuropathy, cardiomyopathy along with some other diseases such as rheumatoid arthritis, osteoporosis and aging. Glycation of proteins interferes with their normal functions by disrupting molecular conformation, altering enzymatic activity, and interfering with receptor functioning. AGEs form intra- and extracellular cross linking not only with proteins, but with some other endogenous key molecules including lipids and nucleic acids to contribute in the development of diabetic complications. Recent studies suggest that AGEs interact with plasma membrane localized receptors for AGEs (RAGE) to alter intracellular signaling, gene expression, release of pro-inflammatory molecules and free radicals. The present review discusses the glycation of plasma proteins such as albumin, fibrinogen, globulins and collagen to form different types of AGEs. Furthermore, the role of AGEs in the pathogenesis of diabetic complications including retinopathy, cataract, neuropathy, nephropathy and cardiomyopathy is also discussed.

• Journal of the Korean Applied Science and Technology
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• v.30 no.4
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• pp.664-671
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• 2013

Determination of xanthan gum as watersoluble-polymer in commercial cosmetic samples was carried out by High Perfomance Liquid Chromatography(HPLC). An $C_{18}$ reversed-phase column and the selected ELSD detector was applied. The 25mM ammonium acetate/acetonitrile was used for the mobile phase of gradient conditions. The analysis results of HPLC showed good linearity with correlation coefficient of $r^2=0.9993$ in the rage of $50.3{\sim}604.1{\mu}g/ml$ and detection limit of $12.0{\mu}g/ml$.