• Journal of the Korean Chemical Society
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• v.29 no.1
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• pp.31-37
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• 1985

N-Acetyl-1-phenylalanyl-1-phenylalanine methyl ester (APhPhMe), N-acetyl-l-phenylalanine methyl ester (APhMe) and N-acetyl-1-phenylalanyl-1-alanine methyl ester (APhAlMe) were used as model compounds to investigate a protein denaturation under various temperatures and pressures. Overall, the solubility of APhPhMe in water increased with increasing pressure and that of APhMe decreased. However, the solubility of APhAlMe was nearly same. The values of volume change of APhPhMe were -0.9, -1.47, -1.09, -1.52 ml/mole at 20, 30, 40 and 50$^{\circ}C$, respectively, and those of APhMe were +6.0, +7.0, +7.5 ml/mole at 20, 30 and 40$^{\circ}C$, respectively. But those of APhAlMe were nearly zero at the measured temperature. The experimental result seems to be explained by the hydrophobic interaction and hydrogen bond of peptide bonds. In the compounds which have only peptide bonds and which have both a pretty large hydrophobic group and a peptide bond in the molecules, the hydrogen bond between peptide bonds is more dominant than the hydrophobic interaction. However, when the number of peptide bond and hydrophobic group increase simultaneously, the hydrophobic interaction seems to be more dominant.

• The Journal of the Korea Contents Association
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• v.18 no.9
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• pp.69-80
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• 2018

D. J. Haraway's cyber-feminism and Kim Seon Hee's eco-feminism are so different in the perspective of the modern scientific technology. While cyber-feminism thinks the outcome of the modern scientific technology positively, eco-feminism criticizes the totalitarianism and the human negation which the modern scientific technology gives rise to. Cyber-feminism gives us an image of the future female, but exposes an easygoing way of thinking of the modern scientific technology. On the other hand eco-feminism takes notice of the risk, that the modern scientific technology can be abused by the power of the minority, but fails in overcoming of the traditional view of female.

• Korean Journal of Plant Taxonomy
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• v.43 no.4
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• pp.296-299
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• 2013

A newly recorded species, Fimbristylis hookeriana Boeckeler, was found in Gyema-ri, Hongnongeup, Yeonggwang-gun, Jeollanam-do and Munyeo-do Is., Gunsan-si, Jeollabuk-do, Korea. Fimbristylis hookeriana is closely related to F. dichotoma, which has ovoid spikelets, deciduous scales, pubescent culms, and short style. However, this species is distinguished by very narrowly ovoid spikelets, persistent scales, glabrous culms, and long style. We propose a new Korean name, 'Ba-Wi-Ha-Neul-Ji-Gi', meaning that this inhabits on dried rocks near seashore. Redescription, illustrations, photographs, table, and a key to species of the Fimbristylis Vahl in Korea are provided.

• Korean Journal of Plant Taxonomy
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• v.43 no.1
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• pp.56-62
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• 2013

Echinochloa oryzoides (Ard.) Fritsch (Na-do-non-pee), was found at paddy fields of Jeonranamdo on a large scale after a first discovery at Masan, Kyeongsangnamdo. This species was not easily distinguished from rice before flowering at the paddy field because of a similar morphology to rice. It is, however, distinguished from other species of the Korean Echinochloa by reliable morphological characters such as horizontal or drooping panicles at maturity, lower glumes with usually 1/4-2/5 as long as the spikelets, awned lower lemmas, and the number of chromosomes, 2n = 54. Echinochloa oryzicola (Vasinger) Vasinger was distinguished from E. oryzoides by erect panicles, lower glumes with at least 1/2 as long as the spikelets, and the number of chromosomes, 2n = 36.

• KSBB Journal
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• v.11 no.2
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• pp.193-200
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• 1996

In molecular biology, type-II restriction endonuclease, which specifically recognize and cleave DNA at a limited number of sites, have been exploited as a means of characterizing DNA fragments, DNA mapping for genetic engineering. Type-II restriction endonucleases have been found to modulate their substrate specificity under modified conditions such as extreme pH, ionic strength, high enzyme concentration, substitution of metallic cofactors or addition of organic solvents. This study was initiated to investigate the modification of recognition specificity of BamHI according to the different pH and organic solvent under the given buffer condition. The specificity of BamHI is highly depends on the presence of hydrophobicity (LogP: partition coefficient) and pH of reaction solution. The specificity of BamHI is changed in range of LogP -1.03∼-1.35(at pH 7.5), -1.03∼-2.5 (at pH 8.0), -0.75∼-0.25(at pH 8.5), 0.32∼-2.5(at pH 8.9), respectively. Alteration of specificity appears in lower concentration of organic solvent when the reaction occurs in more alkali pH. For example, in DMSO solution, alteration of specificity appears in 20% concentration at pH 7.5 but in 4% concentration at pH 8.9.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.1
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• pp.45-51
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• 2015

PBDEs (polybrominated diphenyl ehters) are rarely dissolved in water due to their strong hydrophobicity and large molecular mass so not many researches were done in aqueous environment compared to other environmental compartments. However, the mass loading from wastewater treatment plant into aquatic environment, re-suspension from bottom sediment and partitioning from floating particles and colloids may not be negligible. It is, therefore, important but also difficult to investigate PBDEs in water environment. Recent overcoming resolution towards this barrier to monitor hydrophobic organic compounds in aquatic environment is using passive sampling technique like semipermeable membrane device. By using passive sampling, it might be possible to obtain long-term reproducible monitoring result and detect the trace amounts of PBDEs, with controlling fluctuation of surrounding environmental factors during the sampling event. So therefore, this study is purposed to confirm the possibility of using SPMD (semi-permeable membrane device) as water monitoring tool. Grab samples, composite samples and SPMDs were applied in river bank to evaluate the concentration difference and temporal fluctuation by various water sampling method, and to assess the water concentration prediction capability of SPMD for the PBDEs.

• Journal of the Korean Applied Science and Technology
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• v.36 no.2
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• pp.531-540
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• 2019

Hydrophilic and hydrophobic nanosilica and tetraethyl orthosilicate (TEOS) as a coupling agent was used to form a coarse spike structure as well as an excellent reactive hydroxyl groups on the glass surface. Then, a second treatment was carried out using a trichloro-(1H,1H,2H,2H)perfluorooctylsilane(TPFOS) solution for ultimate water repellent glass surface formation. The formation of hydrophobic coating layer on glass surface using silica aerosol, which is hydrophobic nanosilica, was not able to form a durable hydrophobic coating layer due to the absence of reactive -OH groups on the surface of nanosilica. On the other hand, a glass surface was first coated with a coating liquid prepared with hydrophilic hydroxyl group-containing nanosilica and hydrolyzed TEOS, and then coated with a TPFOS solution to introduce a hydrophobic surface on glass having a water contact angle of $150^{\circ}$ or more. The sliding angle of the coated glass was less than $1^{\circ}$, which meant the surface had a super water-repellent property. In addition, as the content of hydrophilic nanosilica increased, the optical transmittance decreased and the optical transmittance also decreased after 2nd coating with the TPFOS solution. The super-hydrophobic property of the coated glass was remained up to 50 times of rubbing durability test, but only hydrophobic property was shown after 200 times of rubbing durability test. Conclusively, the optimal coating conditions was double 1st coatings with the HP3 coating solution having a hydrophilic nanosilica content of 0.3 g, and subsequent 2nd coating with the TPFOS solution. It is believed that the coating solution thus prepared can be used as a surface treatment agent for solar cells where light transmittance is also important.

• Korean Journal of Social Welfare Studies
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• v.41 no.4
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• pp.5-44
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• 2010

The main purpose of this study is to critically examine the existing theoretical as well as analytical scope of 'sexual minority' in Social Welfare, and to (re)construct and expand it incorporating feminist theories on sexuality. The body of literature on sexual minority or homosexuality in social welfare in Korea as well as in the West can be characterized as two distinct features: first, medical discourse leaning on pathological perspective which perceives homosexuality as a disease or defect, homosexual as a pervert; and second, human rights perspective premised upon the idea of diversity and multi-culturalism, both which are anchoring at 'essentialism.' Based upon the understanding of sexuality as a social construct, we argue that feminist insight on sexuality can lead to reconceptualizing homosexuality and reorienting theories and practices in social welfare. From radical feminism to postmodern queer theories, feminists have developed diverse ideas and complex theories on sexuality and homosexuality, including the concept of 'compulsory heterosexuality,' 'lesbianism as political resistance,' and 'performative gender.' For feminists, particularly, sexuality which is constructed in the complex power matrix of dominations to producing and maintaining inequalities and discriminations is not merely a distinctive variable, but one of the important organizational principles such as gender, class, race, age, and nationality. This epistemological principle will hopefully shed lights on alternative 'knowledge' on homosexuality in social welfare, and lead to significant contribution to its critical expansion in theory and practice.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.11a
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• pp.5-8
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• 1998

기존의 바이폴라 논리회로에서 신호변환시 베이스 영역의 소수 캐리어를 빨리 제거 하기 위해서, 베이스 부분의 매몰충을 줄여서 npn트랜지스터의 베이스와 에피충과 기판사이에 병합 pnp 트랜지스터를 생성한 트랜지스터와 게이트 당 전달 지연 시간을 측정하기 위한 링-발진기를 설계, 제작하였다. 게이트의 구조는 수직 npn 트랜지스터와 기판과 병합 pnp 트랜지스터이다. 소자 시뮬레이션의 자료를 얻기 위하여 수직 npn 트랜지스터와 병합 pnp 트랜지스터의 전류-전압 특성을 분석하여 특성 파라미터를 추출하였다. 결과로서 npn 트랜지스터의 에미터의 면적이 기존의 접합넓이에 비해서 상당히 적기 때문에 에미터에서 진성베이스로 유입되는 캐리어와 가장자리 부분으로 유입되는 캐리어가 상대적으로 많기 때문에 이 많은 양은 결국 베이스의 전류가 많이 형성되며, 또 콜렉터의 매몰층이 거의 반으로 줄었기 때문에 콜렉터 전류가 적게 형성되어 이득이 낮아진다. 병합 pnp 트랜지스터는 베이스폭이 크고 농도 분포에서 에미터의 농도와 베이스의 농도 차이가 적기 때문에 전류 이득이 낮아졌다. 게이트를 연결하여 링-발진기를 제작하여 측정한 AC특성의 출력은 정현파로 논리전압의 진폭은 200mV, 최소 전달 지연시간은 211nS이며, 게이트당 최소 전달지연 시간은 7.26nS의 개선된 속도 특성을 얻었다.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1997.10a
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• pp.402-408
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• 1997

일정 학습계수와 이진 강화함수를 지닌 자기조직화 형상지도(Self-Organizing Feature Map)신경회로망을 FPGA위에 하드웨어로 구현하였다. 원래의 SOFM 알고리즘에서 학습계수가 시간 종속형인데 반하여, 본 논문에서 하드웨어로 구현한 알고리즘에서는 학습계수가 일정인 값으로 고정되며 이로 인한 성능저하를 보상하기 위하여 이진 강화함수를 부가하였다. 제안한 알고리즘은 복잡한 곱셈 연산을 필요로 하지 않으므로 하드웨어 구현시 보다 쉽게 구현 가능한 특징이 있다. 1개의 덧셈/뺄셈기와 2개의 덧셈기로 구성된 단위 뉴런은 형대가 단순하면서 반복적이므로 하나의 FPGA위에서도 다수의 뉴런을 구현 할 수 있으며 비교적 소수의 제어 신호로서 이들을 모두 제어 가능할 수 있도록 설계하였다. 실험결과 각 구성부분은 모두 이상 없이 올바로 동작하였으며 각 부분이 모두 종합된 전체 시스템도 이상 없이 동작함을 알 수 있었다.