• International Journal of Industrial Entomology and Biomaterials
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• 제29권2호
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• pp.169-178
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• 2014

In this study, we investigated genetic diversity of 22 microsporidian isolates infecting tropical tasar silkworm, Antheraea mylitta collected from various geographical forest locations in the state of Jharkhand, India, using polymerase chain reaction (PCR)-based marker assay: random amplified polymorphic DNA (RAPD). A type species, NIK-1s_mys was used as control for comparison. The shape of mature microsporidians was found to be oval to elongate, measuring 3.80 to $5.10{\mu}m$ in length and 2.56 to $3.30{\mu}m$ in width. Of the 20 RAPD primers screened, 16 primers generated reproducible profiles with 298 polymorphic fragments displaying high degree of polymorphism (97%). A total of 14 RAPD primers produced 45 unique putative genetic markers, which were used to differentiate the microsporidians. Calculation of genetic distance coefficients based on dice coefficient method and clustering with un-weighted pair group method using arithmetic average (UPGMA) analysis was conducted to unravel the genetic diversity of microsporidians infecting tasar silkworm. The similarity coefficients varied from 0.059 to 0.980. UPGMA analysis generated a dendrogram with four microsporidian groups, which appear to be different from each other as well as from NIK-1s_mys. Two-dimensional distribution based on Euclidean distance matrix also revealed considerable variability among different microsporidians identified from the tasar silkworms. Clustering of few microsporidian isolates was in accordance with the geographic origin. The results indicate that the RAPD profiles and specific/unique genetic markers can be used for differentiating as well as to identify different microsporidians with considerable accuracy.

• 한국항해항만학회지
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• 제30권5호
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• pp.381-387
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• 2006

최근 우리나라 해기교육대학은 제3국 해기사의 국적선 승선, 국제경쟁력의 약화, 3D업종의 취업 및 이공계 기피현상 등과 같은 교육 환경 변화로 인하여 큰 어려움에 직면하고 있는 실정이다. 이러한 교육환경 변화에 능동적으로 대처함으로써 21세기 해양혁명의 시대에 필요한 우수한 해기인력을 양성할 수 있는 효율적인 방안을 모색하기 위하여 한국해양대학교 해사대학 재학생을 대상으로 입학, 학업, 대학생활, 승선실습 및 진로선택의 5개 과정에 대하여 설문조사를 실시하였고, 학생들의 변화된 의식구조 및 학교생활풍토를 파악하여 현 해기교육시스템의 문제점을 도출하고 그 해결 방향을 검토하였다.

• 항공우주기술
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• 제6권1호
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• pp.74-82
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• 2007

일정한 샘플링 시간 T마다 발생되는 반작용 휠 타코 펄스의 개수를 세어 구동기의 회전 속도를 측정하는 M 방식은 구현이 간단하고 측정 시간이 일정하다는 장점이 있으나, 저속에서 속도 측정의 해상도가 나빠진다는 단점이 있다. 그에 반해, 펄스와 펄스 사이의 시간 간격을 측정하는 T방식은 저속에서 정밀한 속도를 측정할 수 있으며 측정에 따른 시간 지연이 적다는 장점이 있다. 그러나 이 방법 역시 실제 구현 시 나눗셈이 필요하고 속도 측정 시간이 속도에 따라 가변되는 문제점이 있다. 현재 산업계에서는 전동기의 속도를 측정하기 위하여 M방식과 T방식을 조합한 M/T방식이 널리 사용되고 있지만, 현재 위성 분야에서는 M방식과 T방식중 하나만을 사용하고 있는 실정이다. 그럼으로, 저궤도 위성에서 핵심 구동장치로 사용되는 반작용 휠의 속도를 측정하기 위해서, 기존의 M 방식의 속도 측정방식에 저속에서의 속도 정확도 향상을 위하여 T 방식도 이용해서 속도 측정을 하려한다. 본 연구에서는 이러한 측정 요구조건을 만족할 수 있도록 지상 시험 장비인 위성동역학 시뮬레이터에서 반작용 휠의 모사를 위한 보드 설계를 제시하려 한다.

• 대한물리의학회지
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• 제15권2호
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• pp.83-91
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• 2020

PURPOSE: Postural and structural asymmetry due to muscle imbalances around the lower back and pelvis are the causes of back pain. Muscle imbalances in patients with chronic low back pain affect the pelvic tilt and movement, and it is necessary to assess the pelvic movement ability using the appropriate tools to determine the mediating effects of lower back pain. This paper reports the reliability and validity of the Sensbalance Therapy Cushion (STC) for pelvic movement and proprioception. METHODS: In this study, the Wii balance board (WBB) was used as a golden standard for pelvic movement measurements. FABQ, KODI, Myovision, and Pelvic movement were measured in 50 patients with chronic low back pain. The correlation between the lower-back muscle activity and pelvic movement was checked. The pelvic movement parameter was measured twice to determine the intra-rater reliability. RESULTS: The STC showed high test-retest reliability in the pelvic tilt measurements (ICC = .672 - .809). The test-retest reliability of proprioception measurements (ICC = .588 - .859) and reaction time measurements (ICC = .542 - .836) were also high. The relationship between the WBB and STC showed a significant positive correlation with the pelvic tilt test (p < .01). The posterior pelvic tilt and lower-back muscle activity showed a significant negative correlation (p < .01). The pelvic left tilt and lower-back muscle activity showed a significant negative correlation (p < .05). CONCLUSION: The results revealed the high reliability and validity of the STC. Therefore, the STC can be used as an objective measuring device for evaluating pelvic tilt, proprioception, and reaction time in low back pain patients.

• 한국운동역학회지
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• 제15권4호
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• pp.143-151
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• 2005

This study was conducted to investigate the technical factors of Cuervo forward straight vaults with single twist, single and half twists, and double twists actually performed by three execellent male gymnasts participated in artistic gymnastics competition of 2003 summer Universiade in Daegu and the 85th National Sports Festival in Cheongju. To accomplish the research goals the Cuervo vaults of three gymnasts were filmed by using three digital camcorders set by 60 Hz, and data were collected through the DLT method of three dimensional cinematography. The kinematic and kinetic variables as each phasic time, CM displacement velocity, release angle inclination angle hip joint angle landing angle, average horse reaction force average moment arm average torque, whoe body's total remote local angular momentum were analyzed, so the following conclusions were reached. Generally to perform the better Cuervo vault, a gymnast should touch down on the board with the great horizontal velocity of the whole body through the fast run-up, and touch down on the horse by decreasing the horizontal displacement of the whole body during the preflight, so raise CM height gradually within a short horse contact time. He should increase the horse reaction force through checking the horizontal velocity of the whole body effectively and the inclination angular displacement of the handstand, if so he can have the large vertical velocity of the whole body. By using the acquired the velocity and the angular momentum of the whole body, he can vault himself higher and twist sufficiently, then he can get better if the body could be tilted by swinging both arms and perform the cat twist with a little flexions at hip joints. According to the above outcomes we can judge that the best athletes is LuBin, the better is YTY, and the next is JSM.

• 한국산업보건학회지
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• 제6권1호
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• pp.17-27
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• 1996

This study was designed to survey exposure levels of formaldehyde among workplaces in some plywood industries and to compare three sampling methods including the impinger method(IM, NIOSH method No. 3500), the solid sorbent tube method(SS, NIOSH method No. 2541), and the passive bubbler monitor method(PB, SKC). The survey was conducted in seven particle board manufacturing factories, two resin manufacturing factories and two plywood manufacturing factories in Incheon area during the period from March 6 to April 20, 1995. The workplaces included were the hot/cold press, the roller/spreader, the soaking/drying, and the reaction/mixing areas. The results were as follows; 1. The average(GM, GSD) concentrations of formaldehyde by sampling methods were 0.11(4.43) ppm by IM, 0.27(2.03) ppm by SS, and 0.29(2.04) ppm by PB, respectively. The concentrations by 1M method were statistically very significantly lower than those of SS and PB methods, particularly at low air borne concentrations of formaldehyde (p<0.001). 2. The area average concentrations of formaldehyde by workplaces measured with PB bubblers were 0.23(2.08) ppm from the press, 0.23(1.77) ppm from the spreader, 0.24(1.51) ppm from the soaking, and 0.46(1.96) ppm from the reaction areas, respectively. The personal average concentrations of formaldehyde by workplaces measured with PB bubblers were 0.30(1.77) ppm from the press, 0.33(1.54) ppm from the spreader, 0.36(1.46) ppm from the soaking, and 0.84(1.19) ppm from the reaction areas, respectively. 3. No statistically significant differences of formaldehyde concentrations among workplaces except the reaction area(p<0.001) were found. 4. Formaldehyde concentrations from personal samples were higher than those of from area sam pies in all workplaces studied. But no statistically significant differences of formaldehyde concentrations both area and personal samples were found. In conclusion, this study found that although formaldehyde concentrations in some plywood industries in Incheon area were below the regulatory limit of 1 ppm, they were over the limits recommended by NIOSH and ACGIH. This study also suggests that the impinger method may underestimate true formaldehyde concentrations. It implies that there will be more workplaces not meeting current regulatory limit if either the solid sorbent or passive bubbler methods were used instead of the impinger method. It is suggested that passive monitors will be a reasonable alternative for area and personal sampling of formaldehyde if the accuracy and validity of passive monitors be verified before use.

• Transactions on Electrical and Electronic Materials
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• 제17권3호
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• pp.150-154
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• 2016

Contact electrodes pose threats like inflammation, metal poisoning, and allergic reaction to the user during long term ECG procedure. Therefore, we present a novel noncontact electrocardiographic electrode designed through microelectromechanical systems (MEMS) process. The proposed ECG electrode consists of small inner and large outer circular copper plates separated by thin insulator. The inner plate enables capacitive transduction of bio-potential variations on a subject’s chest into a voltage that can be processed by a signal processing board, whereas the outer plate shields the inner plate from environmental electromagnetic noise. The electrode lead wires are also coaxially designed to prevent cables from coupling to ground or electronic devices. A prototype ECG electrode has an area of about 2.324 cm², is very flexible and does not require power to operate. The prototype ECG electrode could measure ECG at about 500 um distance from the subject’s chest.

• 한국재료학회지
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• 제24권11호
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• pp.632-638
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• 2014

We investigated the effects of DMAB (Borane dimethylamine complex, C2H10BN) in electroless Ni-B film with addition of DMAB as reducing agent for electroless Ni plating. The electroless Ni-B films were formed by electroless plating of near neutral pH (pH 6.5 and pH 7) at $50^{\circ}C$. The electroless plated Ni-B films were coated on screen printed Ag pattern/PET (polyethylene terephthalate). According to the increase of DMAB (from 0 to 1 mole), the deposition rate and the grain size of electroless Ni-B film increased and the boron (B) content also increased. In crystallinity of electroless Ni-B films, an amorphization reaction was enhanced in the formation of Ni-B film with an increasing content of DMAB; the Ni-B film with < 1 B at.% had a weak fcc structure with a nano crystalline size, and the Ni-B films with > 5 B at.% had an amorphous structure. In addition, the Ni-B film was selectively grown on the printed Ag paste layer without damage to the PET surface. From this result, we concluded that formation of electroless Ni-B film is possible by a neutral process (~green process) at a low temperature of $50^{\circ}C$.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전기물성,응용부문
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• pp.45-48
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• 2003

In the research of proteomics, mass spectrometry analysis is the essential method for identification of the unknown proteins. Trypsin treatment for the sample preparation of mass spectrometry is the inevitable procedure[1]. However, sample preparation procedure is cumbersome and time consuming. To resolve these problems, Temperature controllable microreactor was designed and fabricated. It consists of metering chamber, micro channel, reaction chamber, platinum (Pt) thin film heater and a temperature sensor so that micro metering and mixture of reagent with temperature control can be done on the same chip. The total size of the fabricated microreactor was $37{\times}30{\times}1\;mm^3$ and the size of channel cross section was $200{\times}100{\mu}m^2$. PID temperature controller was realized using NI DAQ, PCI-MIO-l6E-1 board and LabVIEW program.

• 한국신뢰성학회지:신뢰성응용연구
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• 제16권3호
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• pp.238-244
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• 2016

Purpose: Domestic electric railway Regenerative Energy Storage System seriously affects the maintenance cost of the total operating expenses of nearly 60% of the total LCC (Life Cycle Cost) due to high dependence on foreign Leading company. Therefore by developing the system, it is important to lower the maintenance cost in the domestic supply. This study about the capacitor Reliability test and the purpose of this study is development electric railway Regenerative Energy Storage System. Methods: In case of, having a close relation between the temperature and the reaction rate, Accelerated Model was known that according to Arrhenius' law of chemical activity. If you apply this formula in using allowable temperature range of the capacitor can induce the Arrhenius empirical formula used in much Manufacture Fields. We evaluate the capacitors Leading company through the Arrhenius model. in order to providing a base for the localization of Ultra Capacitor. Conclusion: In this paper, we conducted a reliability test. And it was performed by the accelerated life test and Cycle Test with temperature and C-rate. and then MTBF and B10 life are estimated by analyzing the accelerated life test result. This is thought to need detailed study applying complex stress than about whether it matches the actual behavior in electric railway.