치밀층으로 코팅된 다공성 엔지니어링 세라믹스에서의 접촉응력에 의한 균열 거동

김상겸,김태우,김도경,이기성,Kim, Sang-Kyum,Kim, Tae-Woo,Kim, Do-Kyung,Lee, Kee-Sung 한국세라믹학회 2005 한국세라믹학회지 Vol.42 No.8

The engineering ceramic needs the properties of high strength, hardness, corrosion-resistance and heat-resistance in order to withstand thermal shock or applied nonuniform stresses without failure. The densely coated porous ceramics can be used for machine component, electromagnetic component, bio-system component and energy-system component by their high-performances from superior coating properties and light-weight characteristics due to the structure including pore by itself. In this study we controlled the porosity of silica and alumina, $8.2\~25.4\%$ and $23.4\~36.0\%$, respectively, by the control of sintering temperature and starting powder size. We made bilayer structures, consisting of a transparent glass coating layer bonded to a thick substrate of different porous ceramics by a thin layer of epoxy adhesive, facilitated observations of crack initiation and propagation. The elastic modulus mismatch could be controlled using different porous ceramics as the substrate layer. Then we applied 150 N force using WC sphere with a radius of 3.18 mm by Hertzian indentation. As a result, the crack initiation in the coating layer was delayed at lower porosity in the substrate layer, and the damage in the coating layer was relatively smaller at the bilayer structure coated on higher elastic substrate.

인슐린 매개성 Microsomal Epoxide Hydrolase의 발현증가에서 Akt의 역할

김상겸,김봉희,오정민,윤강욱,김충현,강건욱,Kim, Sang-Kyum,Kim, Bong-Hee,Oh, Jung-Min,Yun, Kang-Uk,Kim, Chung-Hyeon,Kang, Keon-Wook 대한약학회 2007 약학회지 Vol.51 No.5

The present study examines the effect of dominant-negative Akt on the insulin-mediated microsomal epoxide hydrolase (mEH) induction in rat hepatocytes. We also assessed the role of insulin in the expression of soluble epoxide hydrrolase (sEH). Insulin increased mEH levels and the enzyme activities, whereas sEH protein expression was unaffected by insulin. The specific PI3K inhibitors or p70 S6 kinase inhibitor ameliorated the insulin-mediated increase in mEH protein levels. Infection with adenovirus expressing dominant-negative and kinase-dead mutant of Akt1 effectively inhibited the insulin-mediated increase in mEH expression and mEH activity. These results suggest that mEH and sEH are differentially regulated by insulin and PI3K/Akt/p70S6K are active in the insulin-mediated regulation of mEH expression.

알루미나에 YSZ가 나노코팅된 층상형 시스템의 인덴테이션 특성평가

김상겸,김태우,김철,신태호,한인섭,우상국,이기성,Kim, Sang-Kyum,Kim, Tae-Woo,Kim, Chul,Shin, Tae-Ho,Han, In-Sub,Woo, Sang-Kuk,Lee, Kee-Sung 한국세라믹학회 2005 한국세라믹학회지 Vol.42 No.1

전자 범 물리적 증착법(Electron Beam Physical Vaper Deposition, EB-PVD)으로 알루미나 상용기판 위에 나노 크기의 YSZ입자를 포함하고 있는 층을 코팅하여 층상형 시스템을 제조하였으며, 이때 기판층의 온도를 600, 700, $800^{circ}C$로 변화시켜 증착되는 YSZ층이 서로 다른 미세구조가 형성되도록 제어하여, 코팅층 미세구조의 변화에 따른 인덴데이션 거동을 고찰하였다 인덴테이션 거동으로는 비커스 인덴테이션과 헤르찌안 인덴테이션으로 피라미드형 압자 혹은 초경 구를 압입하였으며 압입 하중 및 코링층 구조에 따른 경도와 인덴테이션 응력-변형률 곡선을 구하였고, 미세구조와 하중의 증가에 따른 손상 및 파괴거동을 고찰하였다. 기판층의 온도가 향상됨에 따라 증착된 입자의 크기가 보다 증가하고 각진 입자가 형성됨을 알 수 있었고, 서로 다른 미세구조가 인덴테이션 거동에 영향을 주어, $800^{circ}C$에서 증착된 YSZ/A12달 구조가 상대적으로 우수한 특성을 나타내었다. YSZ layer containing nano-sized particles has been deposited on the commercial A1203 substrate by Electron Beam Physical Vapor Deposition (EB-PVD). The role of coating rnjcrostructures of YSZ to indentation damage is studied. The different coating microsouctures are prepared by varying the substrate temperatures from $600^{circ}C$ to $800^{circ}C$ during the deposition. Microhardness test and Hertzian indentation are conducted on the $YSZ/Al_{2}O_{3}$ layered systems. The damage and flilure behaviors have been investigated according to the effect of microstructures and indentation loads. With increasing the substrate temperature during EB-PVD, the overall grain sizes are coarser and more faceted, which microsoucture ultimately influences on the indentation behavior, thus, YSZ/Al_{2}O_{3}$ layered system prepared at the substrate temperature of $800^{circ}C$ shows relatively higher damage tolerance.

마우스 간의 황함유 아미노산 대사에 미치는 베타인의 용량의존성 영향

김상겸,Kim, Sang-Kyum 대한약학회 2009 약학회지 Vol.53 No.2

Acute betaine treatment induces time-dependent changes in the hepatic glutathione (GSH), cysteine and S-adenosylmethionine (SAM) levels. Our previous study demonstrated that betaine administered $1{\sim}4$ hours prior to sacrifice decreased hepatic GSH levels, but these levels were increased when measured 24 hours following the treatment. The present study was aimed to determine dose-dependent effects of betaine on hepatic metabolism of sulfur amino acid in mice. Mice were sacrificed 2.5 or 24 hours after intraperitoneal treatment with betaine at different dose levels ranging from 50 to 1000 mg/kg. The concentrations of methionine and SAM were increased by a betaine dose of 100 mg/kg, and the concentrations of GSH and cysteine were decreased by a betaine dose of 200 mg/kg at 2.5 hours. These changes were augmented with increasing doses of betaine. At 24 hours following betaine treatment, increased GSH and decreased taurine levels were observed from dose levels of 400 mg/kg. Changes in hepatic activities of cystathionine beta-synthase, gammaglutamylcysteine ligase and cysteine dioxygenase were observed from dose levels of $200{\sim}400$ mg/kg of betaine administered 24 hours prior to sacrifice.

절식이 랫트 간의 황함유 아미노산 대사에 미치는 영향

김상겸,Kim, Sang-Kyum 대한약학회 2009 약학회지 Vol.53 No.2

Food deprivation decreases hepatic glutathione (GSH) levels, which is ascribed to alterations in availability of hepatic cysteine, a rate limiting factor for the GSH synthesis. The present study examines the effects of food deprivation on hepatic metabolism of sulfur amino acid in male rats. In rats fasted for 24 or 48 hours, hepatic GSH levels were decreased from $6.70{\pm}0.16{\mu}mol/g$ liver to $4.02{\pm}0.20$ or $4.06{\pm}0.07{\mu}mol/g$ liver, respectively. Hepatic S-adenosylmethionine levels were also decreased in fasted rats, but S-adenosylhomocysteine levels were increased. Hepatic methionine levels were not changed by food deprivation for 48 hours. On the other hand, hepatic cysteine or taurine levels were increased from $106.2{\pm}4.1$ to $130.0{\pm}2.7$ nmol/g liver or from $2.45{\pm}0.43$ to $5.07{\pm}0.78{\mu}mol/g$ liver, respectively, in 48-hour fasted rats. Activity of cystathionine beta-synthase catalyzed homocysteine to cystathionine, was markedly decreased, but activity of betaine homocysteine methyltransferase was increased in fasted rats, indicating that methylation of homocysteine to methionine is activated. Also activity of cysteine dioxygenase, involved in taurine synthesis, was increased. These results suggested that hepatic methionine levels were maintained in rats fasted for 48 hours through increase in homocysteine methylation, and hepatic GSH may serve as a cysteine supplier reservoir in fasting state.

현행 주민등록증의 문제점과 전자주민증 도입에 관한 헌법적 연구

김상겸(Kim Sang-Kyum) 한국비교공법학회 2011 공법학연구 Vol.12 No.2

주민등록증제도는 1960년대 말 한반도 현실을 감안하여 주민관리라는 행정의 효율성을 확보하기 위하여 도입되었다. 이 제도는 여러 차례 개정을 거치면서 11자리로 시작된 주민등록번호는 13자리로, 주민등록증은 종이로부터 홀로그램 등의 기술이 포함된 플라스틱으로 대체되었다. 주민등록증은 시행과정에서 시대의 변화에 따라 여러 문제가 지속적으로 발생하였다. 종이 주민등록증은 위 · 변조가 너무나 용이하여 재질을 플라스틱으로 바꾸었지만, 여전히 위 · 변조를 통한 위법 · 탈법에 도용되는 것을 방지하지 못하고 있다. 더구나 정보사회의 발전에 따른 전자정부의 시대에 주민등록번호는 공행정의 목적뿐만 아니라, 개인의 영역에서도 마구잡이로 이용됨으로써 개인정보침해로 인한 피해를 확산시키고 있다. 1995년 정부는 주민등록법을 개정하여 소위 전자주민카드를 도입을 계획하였다. 그러나 이 계획은 당시 시민단체 등의 반대로 무산되었다. 그렇지만 정보통신기술의 발달로 인한 정보사회의 급속한 변화는 기존의 주민등록증만으로는 문제를 해결하기 어려운 상황에 이르렀고, 2010년 7월 정부는 전자주민증 도입을 위한 주민등록법 개정안을 입법예고하였다. 이번 개정안은 과거 전자주민카드와는 달리 개인의 민감한 정보를 IC칩에 담고 단순한 정보만 표면에 기재되도록 하였다. 이는 현행 주민등록증이 야기하는 문제들인 개인정보의 노출, 손쉬운 위 · 변조로 인하여 범죄에 악용되고 있는 것을 방지하기 위한 것이다. 법이란 사회의 요구에 의하여 제정되고 시행된다. 고도의 정보사회로 변화하고 있는 헌법현실을 무시하고 과거에 집착하는 것은 오히려 기본권보장에 역효과가 발생할 수도 있다. 개인정보의 유출과 오 · 남용 등으로 인한 피해가 갈수록 커지고 있는 것도 현실에서 새로운 주민등록증의 도입에 있어서 사전에 발생할 수 있는 문제들을 차단하는 조치가 선행되어야 한다. 주민등록번호의 사용에 있어서 본래의 목적에 따라 행정목적 등 공적 부문에서만 사용되도록 관련 법제와 제도를 정비하는 것이 병행되어야 한다. 전자주민등록증의 도입에 있어서 기술적 안전조치가 확실하게 담보될 수 있도록 법제화하는 것이 필요하다. 이와 함께 새롭게 제정되는 개인정보보호법에 근거하여 주민등록증의 전자적 수록의 기술적 안정성을 확인하는 절차를 거치는 방안을 마련한다면 개인정보의 유출 위험성을 현저하게 줄일 수 있다. 또한 전자주민증의 전자적 수록내용에 대하여 좀 더 구체적으로 적시하는 것도 필요하다. 그리고 각종의 보안조치에도 불구하고 모든 정보는 해킹으로부터 자유로울 수가 없다는 것을 명심하고 지속적으로 기술적인 안전조치를 보완해야 한다. The current national identification card was introduced in the late 1960s against a backdrop of the dire reality in the Korean peninsula, in order to secure administrational efficiency in managing Korean nationals. This institution has gone through several modification; the eleven-digit ID number became a thirteen-digit one, the identification paper turned into a plastic card with a hologram. Meanwhile, the national ID card has also raised some serious criminal issues. The identification paper changed into a plastic card, because it was often forged and used in committing crimes. But even after the change, forgery and illegality still remains. Moreover, in an information-based society the ID card is also raising the issue of identity theft and violation of personal information right. In 1995, the government planned to introduce the so called electronic ID card by amending the national ID card law, but it did not happen because of fierce objections by civil organizations. However, the drastic change in the information society brought by the development of ICT raised issues which are beyond the scope of the previous law, and in July 2010, the government made an advanced notice of legislation on the amendment of the law in order to introduce the electronic ID card. The electronic ID card, according to the amendment bill, states only basic personal information on the surface, while carrying an IC chip which contains sensitive information. It is designed to prevent crimes which are enabled by the forgery of ID card. The enactment and implementation of law reflects the demand of society. Ignoring the constitutional reality transforming into a highly developed information society can function as an obstacle in guaranteeing basic rights. Preventive measures should be taken in introducing the new ID card in order to block possible problems. Modification of related law and institutions in order to guarantee that the ID number is only used for public purpose, is also needed. In introducing electronic ID card, we should guarantee the technical safety by legislation. Introducing a procedure which confirms the technical safety of the electronic card could reduce the risk of information leakage. Moreover, the law should also elaborate on the specific contents of personal information which will be contained in the card. But it should be kept in mind, that every information is not free from hacking despite each kind of security measures. Therefore, technical safety measures should be constantly improved at the same time.

아동 권리보호의 관점에서 본 국가배상책임제도의 문제점 및 개선방향 - 아동용품·시설로 인한 생명·신체 침해에 대한 국가배상법시행령을 중심으로 -

김상겸(Kim Sang-Kyum),권영복(Kwon Young-Bok) 한국헌법학회 2005 憲法學硏究 Vol.11 No.3

This paper deals with the duty of the State to guarantee children's safety from things and installations for young children. In this paper, I emphasize the fact that children are discriminated in the state redress Act. When children are violated their body and life by things and installations for them being under government or self-governing body control, they may claim just compensation from the State. But the enforcement ordinance of the state redress Act discriminates them for no particular reason. For instance, in the occurrence of lasting physical lesion or death, their compensations are reduced by as much as twenty percent. And, to be twenty, they may not have the right to demand compensation for the lose of labor power or life beyond medical fee and compensation. These compensations provisions are against the constitution. The constitution guarantees human dignity and worth and imposes the duty to implement policies for enhancing the welfare of children. For this reason, Government has to provide special protection for them, and guarantee them the rights of growth and development as fundamental rights. Government must get rid of a discriminatory regulation for compensations in the enforcement ordinance of the state redress Act, and estimate the practical value of childhood to be twenty and recompenses for the lose of labor power or life.

검찰·경찰의 전문영역 수사와 법원의 판결

김상겸(Sang-Kyum Kim) 한국언론법학회 2006 언론과 법 Vol.5 No.1

청소년의 성보호와 신상공개제도: 청소년성범죄자 신상공개의 헌법합치여부를 중심으로

김상겸(Kim Sang-Kyum) 한국헌법학회 2003 憲法學硏究 Vol.9 No.4

In modern state, matter of Protecting the youth is not only a value that has to be protected by the constitution, but also a subject that has to be considered preferentially in the field of legal policy, regarding the youth as a next generation leading the future. The publicity of sex offender can be considered as a part of active policy of nation, which is intending to guarantee the growth and development of the youth, and is also constitutionally acceptable enough. As the commission on Youth Protect recently announced that they consider publicity of photo system as positive, pros and cons are diverse about this issue. But it is a contrastive phenomenon in that nations putting the publicity in practice include photo's publicity in the system. The protect of juvenile itself is constitutionally not contrary to prohibition of ex post facto law, prohibition of duplicable punishment etc. Further, daim which maintains that the system violated one's privacy is also unacceptable in that it does not accord with the constitutional value including youth's growth and development. The Constitutional Court decide constitutional considering that the system, Art. 20 Youth Protection Law, is an active policy of nation to keep safe the youth from potential danger, is ultimately constitutional value to guarantee the sound humanity of the youth. The constitution is not a means to freedom of adults, but a rule to guarantee the safety of individual rights. Punishment on sex offender should be strictly applied through law. But if it is perceived, that law can protect the youth and futhermore the protect of sexuality, solutions of this issue are far distant. Keys to solve this problem are special care of family and society, improvements of social surroundings to control immoral phenomenon and extensions of social self-purification. Law is moral, but never morality. Overlooking this concept, government of law is merely formalized.

방사선환원법을 이용한 직접메탄올연료전지용(DMFC) 삼성분계촉매(PtRu-Sn/VC, PtRu-Ni/VC)의 합성

김상겸(Sang Kyum Kim),박지윤(Ji Yun Park),황순철(Sun Choel Hwang),이도균(Do Kyun Lee),이상헌(Sang Heon Lee),이영우(Young Woo Rhee),한문희(Moon Hee Han) 한국청정기술학회 2013 청정기술 Vol.19 No.3

방사선환원법을 통해 탄소지지체(Vulcan XC-72<SUP>®</SUP>)를 기반으로 한 나노사이즈의 PtRu-Ni/VC와 PtRu-Sn/VC를 합성하였다. 합성된 촉매는 투과전자현미경(transmission electron microscopy, TEM), 주사전자현미경-에너지 분산형 분석기(scanning electron microscopy-energy dispersive spectroscopy, SEM-EDS), X선 광전자 분광기(X-ray photoelectron spectroscopy, XPS), X선 회절(X-ray diffraction, XRD)을 통해 촉매의 표면과 구조 및 성분에 대해 특성평가 되어졌으며, 촉매 전기화학적 효율 및 안정성 대한 평가를 위하여 산소 환원 반응, 메탄올 산화반응과 CO 흡착 효율을 E-TEK사에서 상용촉매로 판매되는 PtRu/VC<SUP>®</SUP> (60 wt% PtRu)와 비교하였으며, 이에 대한 요약은 다음과 같다. 수소 흡?탈착 반응 : PtRu-Sn/VC > PtRu-Ni/VC > PtRu/VC<SUP>®</SUP> (E-TEK). 메탄올산화반응 : PtRu-Sn/VC > PtRu-Ni/VC > PtRu/VC<SUP>®</SUP> (E-TEK). 단위셀 효율 : PtRu-Sn/VC > PtRu-Ni/VC > PtRu/VC<SUP>®</SUP> (E-TEK). Nano-sized PtRu-Ni/VC and PtRu-Sn/VC electrocatalysts were synthesized by a one-step radiation-induced reduction (RIR) (30 kGy) process using distilled water as the solvent and Vulcan XC-72 as the supporting material. The obtained electrocatalysts were characterized by transmission electron microscopy (TEM), scanning electron microscope energy dispersive spectroscopic (SEM-EDS), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), respectively. The catalytic efficiency of electrocatalysts was examined for oxygen reduction, MeOH oxidation and CO stripping decreased in the following order, Hydrogen stripping : PtRu-Sn/VC > PtRu-Ni/VC > PtRu/VC<SUP>®</SUP> (E-TEK). MeOH oxidation : PtRu-Sn/VC > PtRu-Ni/VC > PtRu/ VC<SUP>®</SUP> (E-TEK). Unit cell performance : PtRu-Sn/VC > PtRu-Ni/VC > PtRu/VC<SUP>®</SUP> (E-TEK) catalysts.