• Applied Chemistry for Engineering
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• v.27 no.4
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• pp.444-448
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• 2016

Hollow silicon/carbon (H-Si/C) composites as anode materials for lithium ion batteries were investigated to overcome the large volume expansion. H-Si/C composites were prepared as follows; hollow $SiO_2\;(H-SiO_2)$ was prepared by adding $NaBH_4$ to $SiO_2$ synthesized using $st{\ddot{o}}ber$ method followed by magnesiothermic reduction and carbonization of phenolic resin. The H-Si/C composites were analyzed by XRD, SEM, BET and EDX. To improve the capacity and cycle performance, the electrochemical characteristics of H-Si/C composites synthesized with various $NaBH_4$ contents were investigated by charge/discharge, cycle, cyclic voltammetry and impedance tests. The coin cell using H-Si/C composite ($SiO_2:NaBH_4=1:1$ in weight) in the electrolyte of $LiPF_6$ dissolved in organic solvents (EC : DMC : EMC = 1 : 1 : 1 vol%) has better capacity (1459 mAh/g) than those of other composition coin cells. It is found that the coin cell ($SiO_2:NaBH_4=1:1$ in weight) has an excellent capacity retention from 2nd cycle to 40th cycle.

• Archives of design research
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• v.13 no.3
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• pp.191-200
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• 2000

Recently, as the form of media has been various and computer graphic technology has developed, it has been possible and attempted to present database information 3-dimensionally and dynamically. However, there was not many studies done regarding how to present 3-dimensional and dynamic information. Therefore, this study was conducted to develop presentation techniques and languages of 3-dimensional and dynamic information. This paper consists of four section. First, it was introduced by secondary research that fundamental knowledge and functions for presenting the information by the computer graphics. In other words, it was stated what is possible to present 3-dimensional information on the 2-dimensional screen and which functins becomes better as computer graphic technology has developed. Second, computer graphic model that present database information should also have hierarchical structure that database information has. Thus, it was discussed how to present information regarding how to make a structure of graphic model that present database information. There are two ways to present information- by changing structure of information and by changing graphical presentation techniques. Third, all the graphical presentation language was collected and explained. Finally, the case study of presenting statistical data for baseball players demonstrated concrete example of using graphical presentation language.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.117-117
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• 2003

체외에서 한우 난포란의 감수분열과 배발달 능력의 획득에는 단백질 합성이 수반되어야 한다. 그러나 이러한 변화와 관련된 연구 보고는 거의 전무한 실정이다. 본 실험은 난자의 핵성숙과 관련된 세포질내 단백질 변화를 파악하기 위하여, 체외성숙 시간에 다른 배발달율과 세포질내 단백질을 비교하여 배발달능력 획득과 관련 있는 단백질을 규명하고자 실시하였다. 한우 난소에서 2-8mm의 가시난포로부터 난포란을 회수하였다. 회수된 난포란은 10% FBS와 호르몬이 첨가된 TCM199 용액에서 18시간 또는 24시간 체외성숙을 실시하였다. 난자 세포질내 단백질 변화는 2D gel electrophoresis를 이용하였고, 유의적인 변화를 나타낸 spot은 peptide mass fingerprinting을 통하여 단백질 동정을 실시하였다. 체외수정은 fer-TALP 용액을, 체외배양은 CR1aa 용액을 배양 3일째까지는 0.3% BSA, 그 이후에는 10% FBS와 난관상피세포를 첨가하여 사용하였다. 통계분석은 t-test를 이용하였다. 난자의 세포질에 대한 이차원전기영동 결과 29개의 단백질 spot들을 확인하였다. 한편 체외성숙 18시간째에 PB가 출현된 난자는 PB가 출현되지 않은 난자에 비하여 15개의 spot에서 유의적인 변화를 나타냈다. 이들 중 4개의 단백질 spot은 낮았고, 11개 spot의 수준은 높은 경향이었다. 체외성숙 18시간째와 24시간째의 배발달율을 조사한 결과 18시간째에서 유의적으로 높은 배반포 발달율을 나타냈다. 그리고 체외성숙 18시간과 24시간째 난자의 세포질내 단백질 spot들의 변화를 비교한 결과 PB가 출현된 난자 세포질에서 단백질의 변화와 유사한 경향이었다. 그러나 2개의 단백질 spot은 상반된 경향을 나타냈다. 따라서 본 실험에서 난자의 핵성숙과 관련 있는 15개의 spot을 확인하였고, 이들 단백질 spot중에서 2개가 배발달 능력과 관련이 있을 것으로 사료된다.보다는 육질등급에 많은 영향을 받는 것으로 판단된다. 한편 육질 1등급에서 배발달율이 낮은 이유는 육질 향상을 목적으로 암소를 비육 하는 경우 발생하는 번식장애와 밀접한 관계가 있는 것으로 사료된다.각각 가장 높았다. 배양 8일째 배반포의 세포수에 있어서 총세포수와 TE 세포수는 차이가 없었으나, ICM 세포수가 l0mg 첨가군에서 가장 높았다. 본 실험 결과에서 체외성숙 배지에 NEAA와 EAA 첨가가 배발달율에는 효과가 없었지만, 첨가농도의 증가에 따라 ICM 세포수가 증가하였다. 한편 체외성숙 배지에 LAH 첨가는 첨가 농도가 높을수록 배발달율은 낮았지만 ICM 세포수는 증가하였다.에 Csk가 관여하고 있음을 알 수 있다. 결론적으로 성적 성숙에 따른 생쥐 정소 내 Src-Csk loop의 발현과 Src kinase 활성의 변동은 정소 내 간충조직, 세정관 상피의 증식 및 기능적 분화 과정을 매개하는 생리적 활성분자 수용체 하위의 신호전달 과정에 Src-Csk loop에 의한 조절가능성을 확인할 수 있었다.rugrene의 향기성분이 주요 성분군으로 확인되었다. 2. 생강나무에서 생강의 향기를 발산하는 성분으로는 $\beta$-myrcene, o-terpinolene, phellandrone, ι-limonene, $\beta$-eudesmol, $\delta$-cadinone, elemol, trans-caryophyllene으로 동정되었으며 그 중에서도 phellandrene, $\beta$-eudesmol이 주된 역할을 하는 성분으로 확인하였다. 유의적인 관련성이 나타났고, 복부 비만의 지표인 허리엉덩이둘레비는 GPT, alkaline phosphatase, 공복시 혈당 및 MCV 등 다양한 건강지표와 관련성을 나타내어 향후 비만에 있어 다양한 혈액 성상의 변화 및 역할규명에 대한 연구가 이루어져야 할 것으로 본다.hat

• The Journal of Engineering Geology
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• v.19 no.1
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• pp.81-88
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• 2009

Two dimensional Monte-Carlo simulations of a non-reactive solute plume in isotropic porous media which are physically and chemically heterogeneous are conducted to determine the variations of moment. Retardation factors of 1, 2 and 5 are given to ascertain how the second moments are changed as adsorption increased. Retarded longitudinal second spatial moment, ${Z_{11}}^{'R}(t',l')$, increased during the transport process and as the dimensionless lengths of line plume source, $l_2'$, increased. ${Z_{11}}^{'R}(t',l')$ decreased as the retardation factors increased, and the simulated moments fit well to the first-order analytical results. Retarded longitudinal plume centroid variance, ${Z_{11}}^{'R}(t',l')$, decreased as the dimensionless lengths of line plume source, $l_2'$, increased and as the retardation factor increased. The result indicates that the uncertainty about the plume center decreased, and the ergodic condition for the second spatial moments is far from reaching. Simulated longitudinal one particle displacement covariance, ${Z_{11}}^{'R}(t')$, well consistent with the first-order analytical results for the three degrees of retardation factors of 1, 2 and 5 respectively. It is, consequently, concluded that the retarded longitudinal second moments could be produced by stochastic simulation, and that the first-order analytical results definitely provides very close values of the longitudinal retarded moments.

• Applied Chemistry for Engineering
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• v.26 no.5
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• pp.543-548
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• 2015

Si/C/CNF composites as anode materials for lithium-ion batteries were examined to improve the capacity and cycle performance. Si/C/CNF composites were prepared by the fabrication process including the synthesis and magnesiothermic reduction of SBA-15 to obtain Si/MgO by ball milling and the carbonization of phenol resin with CNF and HCl etching. Prepared Si/C/CNF composites were then analysed by BET, XRD, FE-SEM and TGA. Among SBA-15 samples synthesized at reaction temperatures between 50 and $70^{\circ}C$, the SBA-15 at $60^{\circ}C$ showed the largest specific surface area. Also the electrochemical performances of Si/C/CNF composites as an anode electrode were investigated by constant current charge/discharge test, cyclic voltammetry and impedance tests in the electrolyte of LiPF6 dissolved in mixed organic solvents (EC : DMC : EMC = 1 : 1 : 1 vol%). The coin cell using Si/C/CNF composites (Si : CNF = 97 : 3 in weight) showed better capacity (1,947 mAh/g) than that of other composition coin cells. The capacity retention ratio decreased from 84% (Si : CNF = 97 : 3 in weight) to 77% (Si : CNF = 89 : 11 in weight). It was found that the Si/C/CNF composite electrode shows an improved cycling performance and electric conductivity.

• Journal of Veterinary Clinics
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• v.28 no.6
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• pp.586-590
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• 2011

Three small breed dogs weighing less 5 kg were admitted with dyspnea and cardiac murmurs. One dog had primum type ASD and chylothorax was concurrently noted. Two dogs had secundum type ASD with and without concomitant pulmonic stenosis. Although medical treatment was attempted, two dogs with secundum type ASD died and a dog with primum type ASD was successfully managed with medication. Defects were confirmed by the postmortem examination in two cases. We first describe the comparison of clinical and diagnostic features in different anatomic, hemodynamic, and pathophysiological types of ASD in small breed dogs and they show some differences with ASD in large breed dogs.

• The Journal of the Korean bone and joint tumor society
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• v.17 no.1
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• pp.17-22
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• 2011

Purpose: We analyzed the oncological outcome and prognostic factor of the chondrosarcoma arising from benign bone tumor due to malignant transformation. Materials and Methods: From April 1986 to April 2009, 18 cases were considered eligible. We analyzed retrospectively the patient's characteristics and prognostic factors that affect to the local recurrence and distant metastasis. Results: As classified by primary benign bone tumor, 4 cases were solitary osteochondroma, 11 cases were multiple osteochondromatosis and 3 cases were multiple enchondromatosis. The mean follow-up period was 85 months. The 5-year disease free survival rate of 18 patients was 85.9%. Their overall MSTS score was 25.2 (84%). There were local recurrence in 3 cases and no distant metastasis. We found that tumor location and surgical margin affected to the prognosis significantly. Conclusion: In secondary chondrosarcoma patients, the prognosis was good relatively and tumor location and surgical margin are important prognosis factor.

• Journal of Conservation Science
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• v.17 s.17
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• pp.83-94
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• 2005

Host rock or the standing sculptured Buddha in the Yongamsa temple is macular porphyritic biotite granite, which has gone through mechanical and chemical weathering. The rock around the Buddha statue is busily scattered with steep inclinations that are almost vertically discontinuous planes with the strikes of $N8^{\circ}E$. Especially the development of the joints that cross the major joints causes the structural instability of the rock. The rock of the Buddha statue is separated into several rock blocks because of many different discontinuity. Thus it is estimated that the bed rock has not only plane and toppling failure but also wedge failure in all the sides. Since the differential pressure is imposed on the body of the Buddha in the host rock, it is urgent to give a reinforce treatment of geotechnical engineering for the safe of its structural stability. Very contact area of joints have turned into soil, which promotes the growth of weeds and plant roots, then aggravates the mechanical weathering of the rock. Thus conservational treatments should also be considered to get rid of secondary contaminants and vegetation along the discontinuities and to prevent further damages.

• Applied Biological Chemistry
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• v.46 no.4
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• pp.305-310
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• 2003

Hydrophobic core variant of ubiquitin appeared to have partially folded structure at pH around 2. The intrinsic tryptophan fluorescence emission maximum of this ubiquitin variant at pH 2 showed slight blue shift compare to that of unfolded state, suggesting that some residual tertiary structures remain in this solvent condition. At the same solvent condition, this ubiquitin variant binds with hydrophobic dye, 8-anilinonaphthalene-1-sulfonic acid(AMS), which is known to bind to exposed hydrophobic surface. Furthermore, far-UV circular dichroic spectrum of this ubiquitin variant in the diminished pH was remarkably different from the far-UV CD spectrum of the native state or unfolded state. Based on the molar ellipticity at 220 nm, this ubiquitin variant at pH 2 appeared to have significant amount of secondary structures. All these observations suggest that this ubiquitin variant in the diminished solvent pH has loosely folded hydrophobic core with some secondary structures, which are key features of molten globule conformation. Since molten globule has long been considered as a protein folding intermediate, it is considered that this hydrophobic core variant ubiquitin will serve as a valuable model to study protein folding process.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3813-3820
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• 2014

Recently, with the increase in electrical consumption and the unbalanced power demand and supply, the power reserve rate is becoming smaller and the reliability of the power supply is deteriorating. Under this circumstance, a Battery Energy Storage System (BESS) is considered to be an essential countermeasure for demand side management. On the other hand, an economic evaluation is a critical issue for the introduction of a power system because the cost of BESS is quite high. Therefore, this paper presents economic evaluation method for utility use by considering the best mix method and successive approximation method, and an economic evaluation method for customer use by considering the peak shaving function based on the real time price. From a case study on a model power system and educational customer, it was confirmed that the proposed method is a practical tool for the economic analysis of BESS.