• 한국정보과학회논문지:시스템및이론
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• 제26권10호
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• pp.1237-1247
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• 1999

이질적 분산 환경에서 전자 상거래는 신임장을 기반으로 상거래 참여자들에 대한 인증 서비스가 제공되어야 한다. 본 연구에서는 CORBA 보안 명세 1 를 기반으로 전자 상거래 참여자들에 대한 객체 단위 인증 및 권한 부여 기법을 제공하는 상호 인증 서비스 구조를 제안한다. 이 구조는 Kerberos 2 의 인증 기법 및 인증 키 교환 기법으로 전자 상거래 참여자간에 상대 주체의 신원 확인 뿐 아니라 거래 진행 중 취득한 정보의 근원을 파악할 수 있도록 하였다. 또한 Kerberos 기법을 CORBA 플랫폼 기반의 상호 인증 구조로서 분산 환경에 대해 확장하였으므로 키 관리 등 보안 정보 관리에 있어 효율적이다.Abstract Electronic commerce shall provide its subjects with a credential-based authentication service in the heterogeneous distributed computing environment. In this paper, based on CORBA security service specification 1 which OMG defined, we propose the mutual authentication service for subjects of electronic commerce, providing the authentication of object level and the authenticated key exchange. This proposed structure, by Kerberos 2 for the authentication and the authenticated key exchange, assures not only the identification of a partner but also the confidence of origin of business item for negotiations between subjects of electronic commerce. Since our deployed Kerberos is extended to the mutual authentication service based on CORBA platform, it is efficient for security administration to manage the information such as a key management in the heterogeneous distributed computing environment.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2001년도 춘계학술발표논문집 (상)
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• pp.251-254
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• 2001

대표적인 분산 객체 환경을 위한 프레임 웍으로 1990년대 초 OMG(Object Management Group)에서 발표한 CORBA(Common Object Request Broker Architecture)를 들 수 있다. 이것은 분산, 이기종 환경에서 객체기반 응용 프로그램들의 재사용성(reusability), 이식성, 상호 운용성(interoperability)을 위한 공통 프레임 ???p이다. 하지만 표준 CORBA는 실시간 응용 프로그램 지원을 위한 한계점을 내재하고 있으므로 이를 그대로 적용하기에는 적합하지 않다. 때문에 RT-SIG(Real-Time Interest Special Croup)에서는 실시간 어플리케이션을 지원하기 위한 일련의 작업이 이루어 졌고, 그 산물로는 TAO(The Ace Orb)와 NraD(US Navy Research and Development), lona 사의 Orbix ORB, Lockheed Martin 사에서 개발한 CORBA 등이 있다. 하지만 표준 CORBA 명세서에 따르면 COS(CORBA Object Service)중의 하나인 이벤트 서비스는 실시간 응용프로그램을 지원하기 위해 필요한 실시간 디스패칭과 스케줄링의 보장, 중앙 집중화된 이벤트 필터링과 상관성을 위한 명시, 주기적 처리 지원 등의 기능이 결여되어 있기 때문에 이를 지원하는 실시간 이벤트 서비스가 요구된다. 이러한 요구에 부합하기 위해 필요한 요구사항을 자바 API 형태로 구현하고 향후 성능에 대한 개선 방향을 제시한다.

• 인터넷정보학회논문지
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• 제20권2호
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• pp.69-76
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• 2019

Recent Enterprise System has component driven real-time distributed architecture (RDA) and this kind of architecture should performed with satisfying strict constraints on life cycle of object and response time such as synchronization, transaction and so on. Microsoft's .NET platform supports RDA and is able to implement services including before mentioned time restriction and security service by only specifying attribute code and maximizing advantages of OMG's Model Driven Architecture (MDA). In this study, a method to automatically generate an extended model of essential elements in an enterprise-system-based RDA as well as the platform specific model (PSM) for Microsoft's .NET platform are proposed. To realize these ideas, the functionalities that should be considered in enterprise system development are specified and defined in a meta-model and an extended UML profile. In addition, after defining the UML profile for .NET specification, these are developed and applied as plug-ins of the open source MDA tool, and extended models are automatically generated using this tool. Accordingly, by using the proposed specification technology, the profile and tools can easily and quickly generate a reusable extended model even without detailed coding-level information about the functionalities considered in the .NET platform and RDA.

• Journal of Ginseng Research
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• 제24권3호
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• pp.138-142
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• 2000

흰쥐 대뇌겉질로부터 별아교세포를 배양하여 흥분성아미노산인 L-glutamate에 의하여 유발되는 세포종창(astrocytic swelling)에 대한 ginsenosides의 억제효과를 검토하였다. Glutamate(0.5 mM)를 세포에 가하고 1시간동안 배양하면 swelling을 일으켜, 세포내의 물의 용적([$^3$H]OMG의 uptake량으로 측정)은 대조세포에 비하여 약 2배의 증가를 나타냈다. Glutamate와 함께 ginsenosides Rb$_2$와 Rc를 가하고 배양하면 glutamate에 의한 astrocytic swelling이 용량의존적으로 감소하였다. 세포는 Rb$_2$와 Rc(0.5 mg/ml)에 24시간까지 노출시켜도 MTT reduction이 감소하지 않는 것으로 보아 이 ginsenosides에 의한 swelling의 억제효과는 세포막의 손상에 의한 것이 아님을 알 수 있었다. Rb$_2$와 Rc는 glutamate에 의한 세포내 $Ca^{2+}$농도의 상승을 억제하였다. 따라서 Rb$_2$와 Rc는Ca$^{2+}$의 유입을 억제하므로서 glutamate에 의한 astrocytic swelling을 억제하는 것으로 생각된다.

• 한국수정란이식학회지
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• 제5권2호
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• pp.38-44
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• 1990

This study was carried out to produce superior dairy cattle by embryo transfer. Seven dairy cows were superovulated with divided injection of FSH 4Omg for 5 days started on day 9 to 14 of the estrus cycle and injection of PGF$_2$$\alpha$ 45mg on day 4 of FSH injection. Donor cows were flushed to collect embryos on day 7 or 8 of the estrus cycle. Fresh embryos collected were transferred to synchronized dairy recipients or frozen using glycerol 3 step method to he equilibrated. And 35 embryos which were frozen using glycerol 6 step method were imported from U.S.A. After glycerol dilution of frozen embryos was done by reverse density during freezing. frozen-thawed embryos were transferred to synchronized dairy or beef recipients. The results obtained were as follows; 1. Total of 24 embryos were collected from 7 donor cows flushed and transferable embryos were 18 (75.0%). 2. Among 24 embryos. morula, early blastocyst, blastocyst, expanded blastocyst and unfertilized ova were 3 (12.5%), 1 (4.2%), 10 (41.6%), 4 (16.7%) and 6 (25.0%), respectively. 3. Heat inducing rate after 1st and 2nd injections of PGF$_2$$\alpha$ in Holstein and beef cattle was 83.3% and 71.4% and 62.5% and 69.2%, respectively. 4. Among 56 recipients, 23 head were pregnant (41.1%). The pregnancy rate of fresh embryos was 50.0% (1/2 heads) and the pregnancy rate of frozen embryos which were frozen using glycerol 3 step and using glycerol 6 step imported from U.S.A. was 52.6%(l0/19 heads) and 34.3%(12/35 heads), respectively. 5. The pregnancy rate of blastocyst (60.0%) was higher than that of morula (39.0%), early blastocyst (25.0%) and expanded blastocyst (0%). 6. The pregnancy rate of grade I embryos (52.2%) was higher than that of grade 2 (34.6%) and grade 3 (28.6%). 7. The pregnancy rate according to synchrony of recipient with donor was higher in simultaneous recipient (55.0%) and +l2hrs' (53.8%) than -24hrs' (23.5%), -l2hrs' (20.0%) and +24hrs' (0%).

• Transactions on Control, Automation and Systems Engineering
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• 제3권3호
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• pp.181-189
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• 2001

The software components of embedded control systems get extremely complex as they are designed into distributed systems get extremely complex as they are designed into distributed systems consisting of a large number of inexpensive microcontrollers interconnected by low-bandwidth real-time networks such as the controller area network (CAN). While recently emerging middleware technologies such as CORBA and DCOM address the complexity of distributed programming, they cannot be directly applied to distributed control system design due to their excessive resource demand and inadequate communication models. In this paper, we propose a CORBA-based middleware design for CAN-based distributed embedded control systems. Our design goal is to minimize its resource need and make it support group communication without losing the IDL (interface definition language) level compliance to the OMG standards. To achieve this, we develop a transport protocol on the CAN and a group communication scheme based on the well-known publisher/subscriber model. The protocol effectively realizes subject-based addressing and supports anonymous publisher/subscriber communication. We also customize the method invocation and message passing protocol, referred to as the general inter-ORB protocol (GIOP), of CORBA so that CORBA method invocations are efficiently serviced on a low-bandwidth network such as the CAN. This customization includes packed data encoding and variable-length integer encoding for compact representation of IDL data types. We have implemented our CORBA-based middleware on the mArx real-time operating system we have developed at Seoul National University. Our experiments clearly demonstrate that it is feasible to use CORBA in developing distributed embedded control systems possessing severe resource limitations. Our design clearly demonstrates that it is feasible to use a CORBA-based middleware in developing distributed embedded systems on real-time networks possessing severe resource limitations.

• 한국수정란이식학회지
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• 제6권2호
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• pp.37-46
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• 1991

A field trial was performed to evaluate the effects of hormone treatment on estrus induction, ovulation, embryo transfer and reproductive performance in post-weaning sows. This trial involved 61 mixed breed sows of varying parity on a commercial pig farm. Sows were allocated to one of five trials: control group involved 25 sows that were treated with a single intramuscular injection of 5 ml physiological saline, 6 sows received 1,500 IU PMSG on the day of weanning and 500 IU HCG at the onset of estrus in trial I, 7 sows received 750 IU PMSG on the day of weanning and 500 IU HCG at the onset of estrus in trial II, 5 sows were treated with the same as trial II on day 28 after weanning in trial III. and 18 sows were treated with 10 mg PGF$_2$$\alpha$ plus 2 mg estradiol benzoate on day 31 after weanning in trial IV. Ovarian responses were checked by laparotomy and ova were recovered by oviducal flushing between 40 and l00hrs after mating. Fertilized ova were transferred into the oviduts of recipient sows synchroni- zed. The results obtained were summarized as follows: 1. Percentages of sows detected in standing estrus following treatment were 86~100% among trial groups. The interval from treatment to standing estrus(6l.7$\pm$0.5lhrs) in lOmg PGF$_2$$\alpha$ and 2mg estradial henzoate treated group was significantly earlier than in other trial groups(P<0.05). 2. Average number of ovulations was 11.5~37.8 among trial groups. The ovulation rate in 1,500 IU PMSG and 500 IU RCG treated group (37.8$\pm$ 19.87) was significantly different from other trial groups(P<0.05). 3. Ova were recovered by oviducal flushing between 40~ l00hrs after mating and recovery rates of ova wore 91.4% between 40~59hrs. 4. Fertilized ova were transferred into the oviducts of 8 recipient sows synchronized with 7 to 17 ova per animal. Three of the recipients were pregnant and delivered 25 piglets. 5. Four of the donor sows in those embryo collection was not successful were pregnant following oviducal flushing and delivered 23 piglets. 6. Recurrence of estrus and farrowing performance of experimental sows were observed following the experiment was no difference among trial groups, respectively.

• 한국식품영양학회지
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• 제4권1호
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• pp.21-34
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• 1991

The purposes of this studies were to investigate the effect of dietry Se levels and alcohol administration on the lipid hyperoxidation and the lipid metabolism in the rat. Seventy two male rats of Sprague-Dawley Strain weighting about 58~629 were divided into 12groups. The dietary Se levels were 10, 0.4 and Omg, and the dietary a-tocopherol levels were 150 and 0mg per kg diet, respectively. Alcohol-administrated groups received drinking water solution containing 10% of ethanol from the 3-weeks of experimental periods. The obtained experimental results are summarized as follows. 1. Food intake, body weight gain and food efficiency ratio were significantly lower in H-, L-and alcohol administrated groups(-A) by administrated Se and alcohol in diet. The weight of liver and spleen tended to be greater in H- and alcohol administrated groups. 2. The glutathione values in liver tend to be lower in alcohol or Vit. E administrated groups than nonadministrated groups. Also there were higher in H- and L- than C-groups, but the increasing range decreased due to administrated alcohol. The lipid peroxide values In liver were significantly higher in alcohol groups, and L- and tocopherol groups were higher values. Specially the increasing of lipid peroxide values were significantly effected by alcohol in low Se and Vit. E groups. 3. The contents of total glyceride in plasma were higher in alcohol groups, there were significantly higher values in alcohol administrated groups under low Se and Vit. E groups. The contents of total cholesterol and HDL-cholesterol In plasma were significantly higher in alcohol groups. 4. The contents of total lipid in liver were higher alcohol groups, and slightly higher values in low Se groups(L-groups) than other groups, also higher values in low Vit. E groups. Those of total glyceride in liver were significantly higher in alcohol groups, appeared highest values when alcohol was administrated in low Se and Vit. E groups. The increasing of total glyceride content was significantly effected by alcohol in low Se groups than that in C-groups.

• 한국농공학회지
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• 제39권5호
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• pp.97-108
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• 1997

Natural wastewater treatment systems using the constructed wetland system were evaluated for the wastewater from the industrial complex in rural areas. For the treatment of wastewater from the industrial complex in rural area, a pilot plant of the constructed wetland system was installed at Baeksuk agri-industrial complex in ChunahnCity, Chunchungnam-Do. The experiment with this pilot plants was performed for 1996 and 1997. Results of the study were summarized as follows. For the BOD and COD, when the pollutant loading of them was about 1 3.8g/$m^2$. day (the concentration was l24.0mg/${\ell}$) arid 24.4g/$m^2$.day(the concentration was 220.Omg/${\ell}$), the removal rate of them was high, 90.2% and 93.4%, respectively. For the SS, the effluent concentration was consistently lower than the water quality standard even though the influent concentration varied significantly, which showed that SS was removed by the system effectively which consist of soil and plants. For the T-N and T-P, when the influent pollutant loading of them were moderately high, 2.8g/$m^2$.day to 7.4g/$m^2$. day(concentration 25.0mg/${\ell}$ to 49.7mg/${\ell}$) for T-N and 1.0g/$m^2$.day to 2.6g /$m^2$.day(concentration 8.6mg/${\ell}$ to 14.7mg/${\ell}$) for T-P, the removal rate of them were 86.5% and 94.0%, respectively. The removal rate by the flow distance increased rapidly in the first 4m from the inlet zone, and gradually there after. The width of system was 2m. Overall, the result showed that constructed wetland system is a feasible alternative for the treatment of wastewater from industrial complex in rural areas. Compared to existing systems, this system is quite competitive because it requires low capital cost, almost no energy and maintenance, and therefore, very cost effective.

• 상하수도학회지
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• 제20권2호
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• pp.257-264
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• 2006

In this study, the treatment of domestic wastewater in a field-scale membrane submerged intermittently aerated activated sludge process($210m^3/day$) was investigated under difference aeration methods. Operating temperature was 5.4 to 25.0 and membrane used in this study is a polyethylene hollow fiber membrane(pore size $0.4{\mu}m$). The range of operating flux was $9.7{\sim}24.4l/m^2-h$ and membrane permeates periodically operated for 7min followed idle for 3 min. The results showed that MIA(modified intermittent aeration) was more efficient in nitrogen and phosphorus removal. The removal efficiencies of T-N and T-P were 73.0% and 69.6% for CIA(conventional intermittent aeration) and 57.5%, 58.6% for MIA (modified intermittent aeration). With application of modified intermittent aeration, DO reached nearly Omg/l within 10 minutes after air off. Organics of influent could be entirely consumed to the denitrification and the P-release without the influence by remained DO in intermittent aeration reactor. Therefore, newly developed KSMBR(Kowaco-KMS-Ssangyoung Membrane Bio-Reactor) process with modified intermittent aeration can be one of the useful process for stable nitrogen and phosphorus removal.