• 멤브레인
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• 제28권4호
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• pp.265-270
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• 2018

이전 연구에서 올레핀/파라핀 분리를 위해 poly(ethylene oxide)(PEO)/Ag nanoparicles (AgNPs)(전구체$AgBF_4$)/p-benzoquinone (p-BQ) 복합막이 제조되었으며, 이 복합체 분리막의 성능은 100시간까지 선택도 10과 투과도 15 GPU로 유지되는 것이 확인되었다. 하지만 전구체인 $AgBF_4$의 가격이 고가이기 때문에, 본 연구에서는 가격 측면에서 경쟁력이 있는 $AgNO_3$를 Ag nanoparticles의 전구체로 사용하여 실험을 진행하였다. 그 결과 이미 존재하고 있는 $NO_3{^-}$가 AgNPs를 감싸고 있기 때문에 분리 성능이 나오지 않는 것으로 관찰되었다. 이번 연구에서는 $AgNO_3$를 Ag nanoparticles의 전구체로 사용하여도 높은 성능을 내기 위해 전자수용체 7,7,8,8-tetracyanoquinodimethane (TCNQ)를 사용하여 PEO, polyvinyl alcohol (PVA), polyether block amide-1657 (PEBAX-1657) 고분자 복합막을 제조한 결과, 고분자와 전자수용체의 영향과는 무관하게 분리성능을 내지 못하는 것으로 분석되었으며, 이는 분리성능에 전구체의 음이온이 결정적 역할을 하는 것으로 분석되었다.

• Safety and Health at Work
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• 제8권1호
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• pp.36-41
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• 2017

Background: Police work is generally sedentary although there may be situations that require physical endurance and strength, such as foot chases and arresting suspects. Factors such as excessive body fat can impede an officer's physical ability to deal with such occurrences. Our objective was to examine associations between officers' body fat percentage (BF%) and performance on a standardized fitness protocol. Methods: Data were obtained from fitness screening among 1,826 male and 115 female officers in a large US police agency. The screening consisted of a 2.4-km run, push-ups, sit-ups, and sit-and-reach test. Sex-specific body fat percentages were estimated from skinfold thickness measured using calipers. Linear regression models were used to examine unadjusted and adjusted mean scores of fitness tests across BF% tertiles. Results: The prevalence of overall fitness was 4.3 times greater in male officers and 3.6 times greater in female officers having the lowest BF% tertile compared with the highest tertile (30.3% vs 7.1% and 46.0% vs 12.8%, respectively). BF% was linearly and positively associated with the time of 2.4-km run (p < 0.001), and linearly and inversely associated with the number of push-ups (p < 0.001), sit-ups (p < 0.001), and the distance of sit-and-reach (p < 0.001) in men. Similar associations were observed in women with the exception of sit-and-reach (p = 0.122). Associations were independent of age, race/ethnicity, rank, and duty station. Conclusion: Overall, BF% was inversely associated with fitness levels in male and female officers. Future longitudinal studies should be initiated to explore the potentially causal relationship between BF% and fitness in law enforcement officers.

• 한국작물학회지
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• 제42권1호
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• pp.14-21
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• 1997

본 시험은 직파재배 유형에 따른 생육 및 수량을 밝히고자 동벼와 농안벼를 공시하여 수행하였던 바 그 결과를 요약하면 다음과 같다. 1. 직파재배 유형간 입수수는 건답평면세조파에서 가장 많았고 무논골뿌림재배에서 적었다. 2. 초기의 경수 증가 속도는 어린모 기계이앙재배가 빨랐으며 유교경비율은 직파재배가 이앙재배보다 낮았다. 3. 출수일수는 직파재배가 어린모 기계이앙재배보다 동진벼는 2∼13일, 농안벼는 10∼18일 길었다. 4. 뿌리의 표층 분포 비율은 담수표면산파>담수표면조파>무논골뿌림>건답평면세 조파>어린모 기계이앙재배 순으로 높았다. 5. 제4절간의 굵기는 재배유형간에 차이가 없었으며 제4절간의 간벽두께는 어린모 기계 이앙재배가 직파재배보다 두꺼웠고 줄기 매몰깊이는 어린모 기계이앙>건답평면세 조파>무논골뿌림>담수표면 조파>담수표면산파 순으로 깊었다. 6. 중심고는 직파재배가 어린모 기계이앙재배보다 높았고 모멘트는 어린모 기계이앙재배가 낮았으며 도복지수는 어린모 기계이앙재배가 가장 낮았고 무논골뿌림, 건답평면세 조파, 담수표면조파, 담수표면산파 순으로 낮았다. 7. 도복은 농안벼에서는 발생하지 않았거나 매우 경미하였으나 동진벼는 담수표면직파>담수표면조파>무논골뿌림>건답직파=어린모 기계이앙의 순으로 도복발생이 심하였다. 8. 수량 구성요소와 수량성은 품종간에는 유의적인 차이가 인정되었으나, 어린모 기계이앙 재배와 직파재배, 그리고 직파재배와 유형간에는 유의적인 차이가 없었다.

• 한국운동역학회지
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• 제22권3호
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• pp.357-363
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• 2012

The purpose of this study was to investigate the effects of different saddle heights on lower-limb joint angle and muscle activity. Six elite cyclists(age: $32.2{\pm}5.2years$, height: $171.0{\pm}3.5cm$, weight: $79.7{\pm}5.6kg$, cycle career: $13{\pm}6.2years$) participated in three min. submaximal(90 rpm) pedaling tests with the same load and cadence based on saddle heights where subject's saddle height was determined by his knee flexion angle when the pedal crank was at the 6 o'clock position. Joint angles(hip, knee, ankle joints) and the activity of lower limb muscles(biceps femoris(BF), vastus lateralis(VL), tibialis anterior(TA) and gastrocnemius medial(GM)) were compared by measuring 3D motion and electromyography(EMG) data. Results showed that there were significant differences in minimum hip & knee joint angle and range of motion of hip and knee joint between saddle heights. Onset timing and integrated EMG of only BF among 4 muscles were significantly different between saddle heights. Especially there was a negative relationship between minimum hip joint angle and onset timing of BF in most subject, which means that onset timing of BF became fast as the degree of bending of the hip joint became larger by saddle height. Optimal pedaling will be possible through increased amount of muscle activation due to the appropriate burst onset timing by proper pedaling posture with adjusted saddle height.

• Asian-Australasian Journal of Animal Sciences
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• 제21권9호
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• pp.1227-1232
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• 2008

Carcass characteristics data of Hanwoo (N = 1,084) were collected from two stations of the National Livestock Institute of Animal Science (NIAS), Korea and records from thirteen individual cow-calf operators were analyzed to estimate variance and covariance components and the effect of different slaughter endpoints. Carcass traits analyzed were cold carcass weight (CWT, kg), REA (rib eye area, cm2), back fat thickness (mm) and marbling score (1-7). Four different models were examined. All models included sex and contemporary group as fixed effects and the animal's direct genetic potential and environment as random effects. The first model fitted a linear covariate of age at slaughter. The second model fitted both linear and quadratic covariates of age at slaughter. The third model fitted a linear covariate of body weight at slaughter. The fourth model fitted both linear covariates of age at slaughter and body weight at slaughter. Variance components were estimated using the REML procedure with Gibb's sampler. Heritability estimate of CWT was in the range of 0.08-0.11 depending on the model applied. Heritability estimates of BF, REA and MS were in the ranges of 0.23-0.28, 0.19-0.26, and 0.44-0.45, respectively. Genetic correlations between CWT and BF, between CWT and REA, and between CWT and MS were in the ranges of -0.33 - -0.14, 0.73-0.84, and -0.01- 0.11, respectively. Genetic correlations between REA and BF, between MS and BF and between REA and MS were in the ranges of -0.82 ~ -0.72, 0.04~0.28 and -0.08 ~ -0.02, respectively. Variance and covariance components estimated varied by model with different slaughter endpoints. Body weight endpoint was more effective for direct selection in favor of yield traits and body weight endpoints affected more of the correlated response to selection for the traits of yield and quality of edible portion of beef.

• Journal of Animal Science and Technology
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• 제60권9호
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• pp.22.1-22.7
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• 2018

Background: Cooking temperature and consequently doneness of beef muscles are most important for the palatability and consumer acceptability. Current study assessed the response of mechanical texture of Hanwoo muscles as a function of cooking temperature at different ageing days. Six muscles (Psoas major (PM), Longissimus thoracics (LT), Gluteus medius (GM), Semimembranosus (SM), Biceps femoris (BF) and Triceps brachii (TB)) were collected from each 10 Hanwoo steers. Warner-Bratzler WB-shear force (WBSF) and texture profile analysis (TPA) texture profiles were determined after 3 or 21 days of chiller, and randomly assigned to four groups; non-cooked, cooked at 55, 70 or $85^{\circ}C$. Results: Toughness of WBSF and TPA hardness of Hanwoo muscles were presence in the order of LT = PM = GM = SM < BF = TB (p < 0.001) for non-cooked raw muscle, and PM < LT = GM = SM < TB=BF (p < 0.001) for cooked meat aged for 3 days. WBSF linearly increased in 3 days aged meats after cooked at a higher temperature (P < 0.05). On the other hand, toughening of the muscles were significantly (P < 0.05) differed at various temperature when muscles were aged for 21 days. WBSF of PM and LT muscles were significantly increased at a higher cooking temperature, while other muscles (i.e., GM, SM, BF, TB) showed the lowest values at $70^{\circ}C$. In the case of TPA hardness, the effect of cooking temperature was very less in the toughness of the muscle (P > 0.05). Conclusion: Taken together, these findings clearly showed that the toughness of the muscle highly depends and varies upon the temperature and ageing of the muscle. Moreover, the effect of cooking temperature was very limited on aged muscles. The results mirror the importance of cooking temperature for objective measurements which ultimately estimate sensory tenderness and other quality traits.

• 한국운동역학회지
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• 제17권4호
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• pp.181-190
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• 2007

The purpose of this study was to analyze the muscle fatigue for lower limbs during the level and downhill running. The subjects were 6 males of twenties who have no experience to get the injury in the lower limbs and required to run on the level and downhill which was -7% grade treadmill at 8.3km/h. EMG signal was gained by ME3000P8 Measurement Unit and computed the Median Frequency(MF) with the power spectrum analysis in the Megawin software. Rectus femoris(RF), Vastus lateralis(VL), Gluteus medius(GLU), Biceps Femoris(BF), gastrocnemius medial head(GM), gastrocnemius lateral head(GL), Tibialis anterior(TA) were selected. The result of this study were as follows: The MF of RF decreased in the downhill running than level running in length of time but, the MF of VL was opposite. The MF of BF decreased in the level and downhill running, but, the MF of BF decreased much in the level than downhill running. The MF of GLU decreased much in the downhill running but, almost no change in the level running. The MF of TA decreased in the level running than downhill running. The MF of GL decreased in the level running but, the MF of GM decreased in the downhill running in length of time. This study analyzed the muscle fatigue of the lower limbs with the median frequency on the basis of an assumption that the impact force for the flexion and extension of the joint and the body mass may be much in the eccentric contraction such as the downhill running than level running. RF and GM showed the muscle fatigue in the downhill running than level running. BF and GL showed the muscle fatigue in the level running than downhill running.

• 한국전기전자재료학회논문지
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• 제29권2호
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• pp.90-94
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• 2016

In this work, [$Pb(Mg_{1/2}W_{1/2})_{0.03}(Ni_{1/3}Nb_{2/3})_x(Zr_{0.5}Ti_{0.5})_{0.97-x}O_3-BiFeO_3$] (x=0.02 to 0.12) composition ceramics were fabricated by the conventional soild state reaction method and their microstructure and piezoelectric properties were investigated according to PNN substitution. The addition of small amount of $BiFeO_3$, $Li_2CO_3$, and $CaCO_3$ were used in order to decrease the sintering temperature of the ceramics. The XRD (x-ray diffraction patterns) of all ceramics exhibited a perovskite structure. The sinterability of PMW-PNN-PZT-BF ceramics was remarkably improved using liquid phase sintering of $CaCO_3$, $Li_2CO_3$. However, it was identified from of the X-ray diffraction patterns that the secondary phase formed in grain boundaries decreased the piezoelectric properties. According to the substitution of PNN, the crystal structure of ceramics is transformed gradually from a tetragonal to rhombohedral phase. The x=0.10 mol PNN-substituted PMW-PNN-PZT-BF ceramics sintered at $920^{\circ}C$ showed the optimum values of piezoelectric constant($d_{33}$), piezoelectric figure of merit($d_{33{\cdot}}g_{33}$), planar piezoelectric coupling coefficient($k_p$) and density : $d_{33}=566$ [pC/N], $g_{33}=29.28[10^{-3}mV/N]$, $d_{33{\cdot}}g_{33}=16.57[pm^2/N]$, $k_p=0.61$, density=7.82 [$g/cm^3$], suitable for duplex ultrasonic sensor application.

• 한국조경학회지
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• 제50권5호
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• pp.13-29
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• 2022

장애인등편의법 개정에 따라 2021년 12월 4일 이후 최초 공원조성계획이 수립되는 공원 및 공원시설은 의무 대상이며, 공원은 장애인 등을 위한 편의시설을 의무적으로 설치해야 한다. 따라서 본 연구는 공원 인증 평가지표와 공원시설의 건축물 인증 평가지표 및 인증 현황 사례의 평가서를 비교 분석하여 공원 인증 평가지표의 개선 방향을 도출하는 데 있다. 연구 방법으로 첫째, 공원과 공원시설의 인증 대상에 대해 공원녹지법과 비교 고찰하였으며, 인증 과정상 차이점, 인증 실적 등을 비교 분석하였다. 둘째, 공원과 건축물 BF인증 평가지표를 분석하여 차이점 및 공통항목을 도출하였다. 셋째, BF인증 공원 4개소와 인증 공원 내 공원시설의 건축물 인증 사례 4개소를 대상으로 자체평가서, 심사 결과를 중심으로 차이점, 문제점 등을 분석한 후 개선방안을 도출하였다. 공원과 건축물 평가지표를 분석한 결과 평가목적, 평가 방법, 평가항목이 공통으로 적용되는 항목은 매개시설의 접근로 7개, 장애인 전용 주차구역 5개, 안내시설의 안내설비 2개, 위생시설의 5개 범주의 14개, 기타 설비 1개로 분석되었다. 위생시설 항목은 공원으로 평가된 사례가 없고 부설 화장실이 아닌 경우 건축물로 인증되는 것을 확인하였다. 공원과 공원시설의 건축물 배점 점수가 자체평가보다 심사 결과 시 하락하였으며, 건축물은 3개소에서 인증 등급이 하락하였다. 표준편차가 가장 큰 항목은 공원은 BF보행 연속성, 건축물은 접근로 중 주 출입구까지의 경로 항목이었다. 위생시설을 제외하고 공통적인 평가항목 19개를 공원과 건축물의 심사 결과를 분석한 결과 1개의 항목을 제외하고는 사례 대상지별 평가항목의 배점 등급 차이가 발생하였다. 따라서 공원과 건축물 공통으로 평가되는 항목에 대한 동일한 세부 산출기준을 적용이 필요하며, 위생시설은 공원 인증된 사례가 없고 건축물로 인증되고 있으므로 부속 화장실에 대한 개념 정립과 공원 위생시설 평가지표 적용에 대한 논의가 필요하다. 공원 내 평가되지 않는 항목에 대한 조정과 공원 특성을 고려한 평가지표를 신설하는 등 공원 특성에 적합한 평가지표가 개발이 필요하다. 본 연구가 공원 인증지표 개선을 위한 기초자료로 활용될 것으로 기대해 본다.

• Journal of Nutrition and Health
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• 제52권2호
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• pp.157-167
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• 2019

본 연구에서는 ice plant의 ethanol 추출물과 분획물의 항산화 및 대장암세포 성장억제 활성을 in vitro 수준에서 평가하는 것을 목적으로 하였다. Ethanol 추출물의 총 폴리페놀 함량 (3.7 mg GAE/g), 총 카로티노이드 함량 ($13.2{\mu}g/g$), DPPH 라디칼 소거활성 (21.0%), 철 환원력 (21.0%)보다 butanol 분획물의 총 폴리페놀 함량 (5.4 mg GAE/g), 총 카로티노이드 함량 ($86.6{\mu}g/g$), DPPH 라디칼 소거활성 (34.9%), 철 환원력 (80.8%)이 더 높았다. 또한 HCT116 대장암세포에서 세포 내 활성산소종 수준을 감소시키거나 세포 성장을 억제하는데 있어서 ethanol 추출물보다 butanol 분획물의 활성이 더 컸다. 대장암세포의 성장을 억제하는데 있어서 butanol 분획물이 ethanol 추출물보다 더 효과적이었던 것은 butanol 분획물의 apoptosis 유도활성이 ethanol 추출물의 활성보다 더 컸고 butanol 분획물만이 G2/M기억류활성을 나타냈기 때문인 것으로 생각된다. 앞으로 이와 같은 결과를 초래하는 주요 활성성분을 분리 동정하고 ice plant의 항산화 활성 및 대장암세포 성장억제 효과가 in vivo 수준에서 재현되는지 검증하며 이와 관련된 세부기전을 탐색하는 심도 있는 연구가 필요할 것으로 생각된다.