• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.402-402
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• 2017

수공구조물 설계 시, 설계홍수량 산정에는 실측 홍수량 자료를 활용한 홍수빈도해석이 필요하다. 그러나 홍수량 자료의 관측연한, 유역변화 등의 신뢰성 문제로 확률강우량을 활용한 빈도홍수량 간접추정방법이 표준화된 실정이다. 문제는 확률강우량 산정에 활용된 확률밀도함수와 그 매개변수에 따른 불확실성이 존재한다는 점이다. 특히 저빈도에서 고빈도로 갈수록 확률밀도함수의 불확실성은 크게 증가하여, 사실상 추정결과에 대한 물리적 의미를 부여하기 어렵다. 이에 본 연구에서는 PMF를 물리적 상한선으로 설정하는 상한분포함수(Upper bounded distribution functions)를 적용하여, 실측 홍수량에 대한 홍수빈도해석 방법을 제안하고자 한다. 검정방법은 먼저, 임의 유역을 대상유역으로 선정하여 홍수빈도해석을 수행하고, 상한분포함수는 EV4, LN4, TDF를 적용한다. 최종적으로 빈도홍수량 간접추정방법과 비교 분석하여, 적용성을 검토하고자 한다. 본 연구결과는 빈도홍수량 간접추정방법에 대한 비교 검토방법에 대한 적절한 대안이 없다는 측면에서 의의를 찾을 수 있으며, 향후 홍수량 자료 신뢰성이 확보되는 시점에서 지역홍수빈도 분석으로 확장할 수 있을 것으로 판단된다.

• Journal of Magnetics
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• v.17 no.3
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• pp.200-205
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• 2012

Recently, applications of the reluctance torque motor have been quite limited due to their inherent limitation of noise and vibration and thus, researches on the reluctance motor have been limited as well. However, with the tremendous increase in the cost of rare earth material magnets, studies of the reluctance torque motor are being conducted more and more. In principle, reluctance torque is generated when the inductance is changed. Therefore, in order to generate continuous torque in the switched reluctance motor, it is necessary to figure out the exact inductance level corresponding to the rotor position and the current level to be applied in that rotor position, respectively. If the current level or the rotor position is not accurately determined, then the generated reluctance torque becomes unstable and undesirable torque ripples prevail to eventually cause noise and vibrations. In this research, a flux switched reluctance motor (FSRM), which is classified into the switched reluctance motor (SRM), was studied. A methodology using the current shaping control according to the rotor position was proposed. Based on the proposed methodology, the optimal current waveform and the torque distribution function for the FSRM to minimize torque ripple was established and demonstrated in this paper.

• Advances in concrete construction
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• v.1 no.1
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• pp.1-27
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• 2013

Discrete steel fibres can increase significantly the bending and the shear resistance of concrete structural elements when Steel Fibre Reinforced Concrete (SFRC) is designed in such a way that fibre reinforcing mechanisms are optimized. To assess the fibre reinforcement effectiveness in shallow structural elements failing in bending and in shear, experimental and numerical research were performed. Uniaxial compression and bending tests were executed to derive the constitutive laws of the developed SFRC. Using a cross-section layered model and the material constitutive laws, the deformational behaviour of structural elements failing in bending was predicted from the moment-curvature relationship of the representative cross sections. To evaluate the influence of the percentage of fibres on the shear resistance of shallow structures, three point bending tests with shallow beams were performed. The applicability of the formulation proposed by RILEM TC 162-TDF for the prediction of the shear resistance of SFRC elements was evaluated. Inverse analysis was adopted to determine indirectly the values of the fracture mode I parameters of the developed SFRC. With these values, and using a softening diagram for modelling the crack shear softening behaviour, the response of the SFRC beams failing in shear was predicted.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.2
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• pp.205-213
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• 1996

본 연구에서는 남자대학생 80명을 대상으로 총 식이섬유 및 조섬유와 영양소 섭취상태를 비교 분석하였다. 남자대학생들의 평균 총 식이섬유 섭취량은 $20.54\pm5.82g으로$ 외국의 잠정적 권장량의 범위(20~30g)에는 들었으나 권장량의 하한치를 약간 상회하는데 그쳤다. 조섬유의 1일 평균 섭취량은 $8.43\pm5.56g으로$ 1일 식이섬유 섭취량의 약 41%에 해당하였으며 그 외 열량 및 다른 영양소의 평균 섭취량은 한국인 영양권장량과 비슷하거나 다소 더 높은 것으로 나타났다. 총 식이섬유 섭취량과 에너지 및 단백질, 당질, 그리고 조섬유의 섭취량 간에는 유의적인 상관관계를 보였으며, 당질이 가장 높은 상관계수(r=0.7232, p<0.001)를 보였다. 또한 조사 대학생들의 총 식이섬유 섭취량과 식품군별 섭취량과의 상관관계수를 보인 것은 채소류 (r=0.6548, p<0.001)였으며 그 다음은 곡류(0.5913, p<0.001)였으며 그 다음은 곡류(0.5913, p<0.001), 해조류(0.3300, p<0.01)였다. 조사 대학생들의 식이섬유 섭취량 중 총식이섬유 급원으로 가장 많이 섭취한 식품은 쌀과 김치였으며, 각각 총 식이섬유 섭취량의 11.98%와 7.64%에 기여하였다. 그 외 학생들이 많이 섭취한 라면, 고춧가루, 냉면, 빵, 콩나물, 밀가루, 깍두기, 무 등이 주요한 식이섬유 급원으로 나타났다. 본 연구의 남자대학생들의 식이섬유 섭취량은 외국의 잠정적 권장량의 범위(20~30g)에 속하였으나 충분한 양을 섭취하고 있는 것은 아니었으며, 오히려 경제수준의 향상으로 인한 식습관의 변화에 민감하게 반응하는 젊은 세대들인 조사대학생들의 장래 식이섬유 소비량은 더욱 감소할 것으로 추정된다. 그러므로 식이섬유 급원식품의 섭취를 증가시키는 방안이 모색될 필요가 있다. 따라서 성인기에 식이섬유 부족으로 나타나는 각종 질병의 위험을 예방하기 위해 정백비 위주의 식사를 지양하고 총 식이섬유 함량이 높은 해조류의 섭취를 널리 교육시키는 것이 바람직할 것으로 사료된다. 또한 보다 광범위하고 체계적인 대상자 선정을 통하여 식이섭취조사가 이루어져 식이섬유 섭취패턴을 연구할 필요가 있다.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.107-114
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• 1997

Various fractions of apple fibers such as crude pulp, total dietary fiber, soluble dietary fiber, and insoluble dietary fiber were prepared and added to the proteose peptone-yeast extract-fildes (PYF) media to see their effects on the growth of type cultures of intestinal bacteria. Most microbes tested in this experiment grew well in PYF media with the soluble dietary fiber of apple than with the insoluble dietary fiber. Especially Bifidobacterium species such as B. adolescentis, B. animalis, B. infantis, B. longum, B. thermophilum showed higher growth in PYF media containing the soluble dietary fiber than other fiber fractions. However, pectin-added media didn't promote the growth of most microbes used in the experiment. In the in vitro mixed culture using rat feces as starter, the addition of the soluble dietary fiber or pectin to the basal medium showed larger proportion of Bifidobacterium species in total bacteria than that of glucose.

• Progress in Medical Physics
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• v.11 no.1
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• pp.85-90
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• 2000

In radiation therapy, the effects of radiation are decided total dose, total treatment times and number of radiation dose fractions. We considered that total dose, total treatment times and number of radiation dose fractions in intensity modulation radiation therapy(IMRT) infuence tumor cell killing. The goal of three dimensional conformal radiation therapy(3DCRT) in radiation therapy is to conform the partial distribution of the prescribed radiation dose to the precise 3D configuration of the tumor, and at the same time, to minimize the dose to the surrounding normal tissues. To optimize treatment volume of tumor, treatment volume will be same tumor volume. All IMRT compare to conventional treatment plus boost IMRT when total dose irradiated 75 - 90 Gy. Because of biological effect, total dose are decreased 12.5 - l5Gy in all IMRT.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.4
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• pp.337-342
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• 2013

Porphyra yezoensis is potentially an excellent source of dietary fiber, amino acids, and eicosapentaenoic acid (EPA) because this red seaweed is available in large quantities and is rich in polysaccharides, proteins, and n-3 fatty acids. This study determined the insoluble dietary fiber (IDF), soluble dietary fiber (SDF), neutral detergent fiber (NDF), acid detergent fiber (ADF), amino acid, and fatty acid contents of P. yezoensis harvested monthly from November 2011 to March 2012. The total dietary fiber (TDF) and IDF contents ranged from 27.2-34.9% and 18.5-26.9%, respectively, and were greater in March than November. The SDF content ranged from 4.9-8.4% and did not differ significantly during growth. Galactose and 3,6-anhydro galactose were the major sugars in IDF and SDF. The higher levels of galactose and 3,6-anhydro galactose in IDF might be due to associated porphyran-type polysaccharides. Mannose and xylose were also major sugars in IDF. The total amino acid contents decreased gradually from November to March. The total amino acid composition of Porphyra was dominated by alanine, glutamic acid, arginine, and aspartic acid. No significant changes in the fatty acid profile were observed throughout the study period. The dominant fatty acid during all seasons was EPA, which comprised as much as 50% of the total fatty acid content.

• Proceedings of the KSRS Conference
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• v.2
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• pp.831-835
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• 2006

NOAA/AVHRR data were used to analyze sea surface temperatures (SSTs) and thermal fronts (TFs) in the Korean seas. Temporal and spatial analyses were based on data from 1993 to 2000. Harmonic analysis revealed mean SST distributions of $10{\sim}25^{\circ}C$. Annual amplitudes and phases were $4{\sim}11^{\circ}C$ and $210{\sim}240^{\circ}$, respectively. Inverse distributions of annual amplitudes and phases were found for the study seas, with the exception of the East China Sea, which is affected by the Kuroshio Current. Areas with high amplitudes (large variations in SSTs) showed 'low phases' (early maximum SST); areas with low amplitudes (small variations in SSTs) had 'high phases' (late maximum SST). Empirical orthogonal function (EOF) analyses of SSTs revealed a first-mode variance of 97.6%. Annually, greater SST variations occurred closer to the continent. Temporal components of the second mode showed higher values in 1993, 1994, and 1995. These phenomena seemed to the effect of El $Ni{\tilde{n}}o$. The Sobel edge detection method (SEDM) delineated four fronts: the Subpolar Front (SPF) separating the northern and southern parts of the East Sea; the Kuroshio Front (KF) in the East China Sea, the South Sea Coastal Front (SSCF) in the South Sea, and a tidal front (TDF) in the West Sea. Thermal fronts generally occurred over steep bathymetric slopes. Annual amplitudes and phases were bounded within these frontal areas. EOF analysis of SST gradient values revealed the temporal and spatial variations in the TFs. The SPF and SSCF were most intense in March and October; the KF was most significant in March and May.

• BMB Reports
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• v.36 no.6
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• pp.552-557
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• 2003

Oligomers with $\alpha$-aminooxy acids are reported to form very stable turn and helix structures, and they are supposed to be useful peptidomimetics for drug design. A recent report suggested that homochiral oxa-peptides form a strong eight-member-ring structure by a hydrogen bond between adjacent aminooxy-acid residues in a $CDCl_3$ solution. In order to design an $\alpha$-MSH analog with a stable turn conformation, we synthesized four tetramers and one pentamer, based on $\alpha$-MSH sequence, and determined the solution structures of the molecules by two-dimensional NMR spectroscopy and simulated annealing calculations. The solution conformations of the three peptidomimetic molecules (TLV, TDV, and TLL) in DMSO-$d_6$ contain a stable 7-membered-ring structure that is similar to a $\gamma$-turn in normal peptides. Newly-designed tetramer TDF and pentamer PDF have a ball-type rigid structure that is induced by strong hydrogen bonds between adjacent amide protons and carbonyl oxygens. In conclusion, the aminooxy acids, easily prepared from natural or unnatural amino acids, can be employed to prepare peptidomimetic analogues with well-defined turn structures for pharmaceutical interest.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.6
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• pp.805-814
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• 2013

A hydraulic dipod platform is used for tracking and stabilizing an antenna system to designate a satellite on a moving vehicle. The 2-DOF controller is very well suited to this controller design object because it is more flexible than the 1-DOF controller when the design object is not only the consideration between stabilizing and tracking but also the trade-off between performance and robustness. The 2-DOF controller synthesis based on the $H_{\infty}$ framework is divided into two design procedures. In this hydraulic dipod platform example, the single-step method shows better performance whereas the two-step method shows better robustness. The difference between these two synthesis results is compared using the structural property of the interconnection system matrix.