• 한국발생생물학회지:발생과생식
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• 제2권2호
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• pp.179-187
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• 1998

부화 및 착상에서 prostaglandins의 역할에 대한 연구는 많으나 배아단계에 따라 포배의 팽창과 부화에 미치는 영향에 대한 연구는 미미하다. 따라서 본 실험에서는 다양한 농도의 prostaglandins를 발생단계에 따라 처리하거나, indomethacin과 prostaglandins의 양 변화를 통해 팽창과 부화에 미치는 영향을 알아보고, 배아 단계별 PG $E_2$와 PG $F_2$$_{\alpha}$의 생합성양 변화양상을 알아보았다. 100$\mu$M이 상 농도의 PG $E_2$처리시 거의 모든 상실배가 퇴화하는 유해성을 보이나 PG $F_2$$_{\alpha}$에 있어서는 관찰되지 않았다. PG $E_2$나 PG $F_2$$_{\alpha}$ 모두에서 배아의 부화를 억제하지만 팽창포배로의 발생은 대조군과 유사하였다. hCG 주사 후 84시간과 96시간 단계 배아에 처리한 경우 부화율이 전반적으로 감소하는 경향을 보였으나 팽창포배로의 발생은 대조군과 유사하였고 PG $E_2$에 의한 세포독성은 발생단계가 높을수록 감소되었다. 한편 배아 단계와 관련없이 PG $F_2$$_{\alpha}$의 농도가 높아짐에 따라 부화가 억제되었다. Indomethacin과 PG $E_2$나 PG $F_2$$_{\alpha}$를 함유한 배양액에서 각 단계의 배아를 배양할 경우 prostaglandins를 단독으로 처리한 경우보다 부화율이 증가하였다. 한편 PG $E_2$의 경우 낮은 농도에서 부화율이 대조군 수준으로 증가하였다. 한편 PG $E_2$ 합성은 발생단계에 따라 급격히 증가한 반면 PG $F_2$$_{\alpha}$는 점진적인 증가를 보였다. 이상의 결과에서 PG $E_2$에 의한 세포독성은 배아 단계가 높아질수록 감소하고, 고농도의 PG $F_2$$_{\alpha}$는 배아의 부화를 억제하였으며, 발생 단계에 따라 prostaglandins의 요구 양이 다름을 알 수 있다. 또한 상실기 이후 배아에서 합성되며, 발생시기에 따라 그 영향이 다르고 팽창과 부화에 관여하는 것으로 사료된다.생 단계에 따라 prostaglandins의 요구 양이 다름을 알 수 있다. 또한 상실기 이후 배아에서 합성되며, 발생시기에 따라 그 영향이 다르고 팽창과 부화에 관여하는 것으로 사료된다.

• Archives of Plastic Surgery
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• 제43권2호
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• pp.197-203
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• 2016

Background The aim of unilateral breast reconstruction after mastectomy is to craft a natural-looking breast with symmetry. The latissimus dorsi (LD) flap with implant is an established technique for this purpose. However, it is challenging to obtain adequate volume and satisfactory aesthetic results using a one-stage operation when considering factors such as muscle atrophy, wound dehiscence and excessive scarring. The two-stage reconstruction addresses these difficulties by using a tissue expander to gradually enlarge the skin pocket which eventually holds an appropriately sized implant. Methods We analyzed nine patients who underwent unilateral two-stage LD reconstruction. In the first stage, an expander was placed along with the LD flap to reconstruct the mastectomy defect, followed by gradual tissue expansion to achieve overexpansion of the skin pocket. The final implant volume was determined by measuring the residual expander volume after aspirating the excess saline. Finally, the expander was replaced with the chosen implant. Results The average volume of tissue expansion was 460 mL. The resultant expansion allowed an implant ranging in volume from 255 to 420 mL to be placed alongside the LD muscle. Seven patients scored less than six on the relative breast retraction assessment formula for breast symmetry, indicating excellent breast symmetry. The remaining two patients scored between six and eight, indicating good symmetry. Conclusions This approach allows the size of the eventual implant to be estimated after the skin pocket has healed completely and the LD muscle has undergone natural atrophy. Optimal reconstruction results were achieved using this approach.

• 설비공학논문집
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• 제21권6호
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• pp.333-339
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• 2009

The objective of this study is to predict optimal intermediate pressure of a 2-stage compression heat pump system using river water. To determine the maximum performance of the 2-stage compression heat pump system, the experimental evaluations on the 2-stage compression cycle were carried out under various operating conditions. Electronic expansion valves were applied to control intermediate pressure and superheat. Based on the experimental data, an empirical correlation for predicting optimal intermediate pressure which considering cycle operating parameters was developed. The present correlation was verified by comparing the predicted data with the measured data. The predictions showed a good agreement with the measured data within a relative deviation of ${\pm}4%$ at various operating conditions.

• 한국지구과학회지
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• 제36권5호
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• pp.419-426
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• 2015

We investigated the high dispersion spectra that had been secured at the center of the planetary nebula NGC 7027 with the Bohyunsan Optical Echelle Spectrograph (BOES) on October, 20, 2009. We analyzed the forbidden lines of [OI], [SII], [OII], [NII], [ClIII], [ArIII], [OIII], [ArIV], [NeIII], [ArV], and [CaV] in the $3770-9225{\AA}$ wavelength region. The expansion velocities were derived from double Gaussian line profiles of the emission lines, after eliminating the subsidiary line broadening effects. The radial variations of the expansion velocities were obtained by projecting the derived expansion velocities: $19.56-31.93kms^{-1}$ onto the equatorial shell elements of the inner and the outer boundaries of the main shell of 2.5(2.1)" and 3.8(3.6)", according to the ionization potential of each ion. Analysis of equatorial shell spectra indicated that the equatorial shell generally expands in an accelerated velocity mode, but the expansion pattern deviates from a linear velocity growth with radial distance. NGC 7027, of which age is about 1000 years or less, might be still at its early stage. During the first few hundred years, plausibly in its early stage, the main shell of PN expands very slowly and, later, it gradually gain its normal expansion speed.

• 한국식품영양과학회지
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• 제28권2호
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• pp.429-437
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• 1999

A mathematical model was established for estimating changes in pressure and volume of permeable kimchi packages. The model comprises the CO2 gas production from kimchi and permeation of O2, CO2 and N2 through the permeable film or sheet. Using the developed model, the effects of various packaging variables on the pressure and volume changes were analyzed for rigid and flexible packag es of kimchi(3% salt content) at 15oC, and then effect of storage temperature was also looked into. In case of rigid pack of 400g, using the plastic sheet of high CO2 permeability and initial vacuumizing can help to relieve the problem of pressure build up. The lower fill weight can further reduce the pressure, but will result in higher packaging cost. For the flexible package of 3 kg, highly permeable films such as low density polyethylene(LDPE) and polypropylene can reduce the volume expansion. Higher ratio of CO2 permeability to O2 and N2 permeabilities are effective in reducing the volume expansion. Increased surface area cannot contribute to reduction of volume expansion for highly permeable flexible packages of kimchi. For the impermeable packages, pressure and volume at over ripening stage (acidity 1.0%) increase with decreased temperature, while those at optimum ripening stage(acidity 0.6%) change little with temperature. Pressure of permeable rigid LDPE package increases with tem perature at any ripening stage, and temperature affects the volume of flexible LDPE package very slightly. Experimental verification of the present results and package design with economical consid eration are needed as a next step for practical application.

• 한국작물학회지
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• 제44권4호
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• pp.391-395
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• 1999

Barnyardgrass had relatively higher growth vigor at the earlier growth stage than inbred rice did, showing the 2 fold higher $\alpha$-amylase activity during the periods of germination and large leaf area Expansion with high net photosynthetic rate at the earlier autotrophic stage, but it performed weak growth at the late growth stage. However, the hlybrid rice Shanyou 63 had significantly higher $\alpha$-amylase activity and net photosynthetic rate than that of barnyardgrass, exhibiting heterosis for two physiologica1 traits during the germination (6~12 days) and autotrophic phase, respectively. Accordingly, hybrid rice, Shanyou 63, exhibited heterotic effect at the early growing stage when were presented with barnyardgrass. Shanyou 63 exhibited stronger tillering ability, faster leaf area expansion and higher net photosynthetic rate than those of barnyardgrass.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 1997년도 제8회 학술강연회논문집
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• pp.43-51
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• 1997

Steady and unsteady numerical simulations are conducted for the experiments performed to investigate the ram accelerator flow field by using the expansion tube facility in Stanford University. Navier-Stokes equations for chemically reacting flows are analyzed by fully implicit and time accurate numerical methods with Jachimowski's detailed chemistry model for hydrogen-air combustion involving 9 species and 19 reaction steps. Although the steady state assumption shows a good agreement with the experimental schlieren and OH PLIF images for the case of $2H_2$+$O_2$+$17N_2$, it fails in reproducing the combustion region behind the shock intersection point shown in the case of $2H_2$+$O_2$+$12N_2$, mixture. Therefore, an unsteady numerical simulation is conducted for this case and the result shows all the detailed flow stabilization process. The experimental result is revealed to be an instantaneous result during the flow stabilization process. The combustion behind the shock intersection point is the result of a normal detonation formed by the intersection of strong oblique shocks that exist at early stage of the stabilization process. At final stage, the combustion region behind the shock intersection point disappears and the steady state result is retained. The time required for stabilization of the reacting flow in the model ram accelerator is found to be very long in comparison with the experimental test time.

• Archives of Plastic Surgery
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• 제47권5호
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• pp.419-427
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• 2020

Background This study evaluated the Blossom system, an innovative self-filling, rate-controlled, pressure-responsive saline tissue expander (TE) system. We investigated the feasibility of utilizing this technology to facilitate implant-based and combined flap with implant-based breast reconstruction in comparison to conventional tissue expansion. Methods In this prospective, single-center, single-surgeon pilot study, participants underwent either implant-based breast reconstruction or a combination of autologous flap and implantbased breast reconstruction. Outcome measures included time to full expansion, complications, total expansion volume, and pain scores. Results Fourteen patients (TEs; n=22), were included in this study. The mean time to full expansion was 13.4 days (standard error of the mean [SEM], 1.3 days) in the combination group and 11.7 days (SEM, 1.4 days) in the implant group (P=0.78). The overall major complication rate was 4.5% (n=1). No statistically significant differences were found in the complication rate between the combination group and the implant group. The maximum patient-reported pain scores during the expansion process were low, but were significantly higher in the combination group (mean, 2.00±0.09) than in the implant group (mean, 0.29±0.25; P=0.005). Conclusions The reported average duration for conventional subcutaneous TE expansion is 79.4 days, but this pilot study using the Blossom system achieved an average expansion duration of less than 14 days in both groups. The Blossom system may accommodate single-stage breast reconstruction. The overall complication rate of this study was 4.5%, which is promising compared to the reported complication rates of two-stage breast reconstruction with TEs (20%-45%).

• 플랜트 저널
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• 제15권2호
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• pp.46-55
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• 2019

기존 메탄 & 질소 팽창 사이클의 효율 개선을 위해 2개의 메탄 팽창 공정 (cold composite curve에 변곡점을 하나 더 추가하기 위해 warm & cold 2개 공정으로 나눔)과 1개의 질소 팽창 공정을 사용한 천연가스 액화 사이클을 소개하기 위한 논문이다. 이전 질소 팽창 사이클 및 메탄 & 질소 사이클과 비교했을 때, 13.92 및 13.13에서 12.08 kW/ton/day로 효율이 8~15% 정도 개선되었다. 순 현재가치(NPV) 기준으로 한 수명 주기 비용 분석(LCC analysis) 또한 약간의 CAPEX 증가는 있지만 프로젝트 순 현재가치가 개선된 결과를 보여준다.

• 문화기술의 융합
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• 제9권5호
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• pp.779-785
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• 2023

비 언어극인 무용에서 무대의상은 시각적 표현에서 중요성을 갖고 있다. 특히 창작무용에서 무대의상은 기존의 기본적인 역할인 장식성이나 신분을 나타내는 시대성 그리고 동작을 위한 기능성 이외에 좀 더 작품에 밀접하게 관련된 확장적 역할을 하고 있다. 우리는 본 연구를 통하여 창작 발레 <'그' 소녀>의 작품에 나타난 무대의상의 확장성을 분석하는 것이 목적이며, 이를 통해 무대의상 디자인에 기초 자료를 제공하고 새로운 방향성을 제안하는 여 연구의 의의를 부여하고자 한다. 창작 발레극 <'그' 소녀>는 피해자들이 겪었을 공포와 공감을 통해 전달하고자 하는 위로를 주제로 2개의 막으로 구성되었으며, 2막의 해방과 '한(恨)'의 춤에서 의상의 확장된 역할이 요구되었다. 의상 디자인은 위안부를 형상화한 '소녀상'에서 영감을 받았으나, 발레 동작의 기능성과 의상에 장치된 끈과 천의 운용의 용이성 등의 전제조건을 바탕으로 3개의 초안 디자인과 재질의 실험을 거쳐 완성되었다. 결론적으로 해방의 춤에서 사용된 끈과 '한(恨)'을 표현한 천을 효과적으로 사용하여 무대의상의 시·공간의 확장성, 조형의 확장성, 상징적 표현의 확장성이 나타남을 알 수 있었다.