• Carbon letters
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• 제7권1호
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• pp.9-18
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• 2006

Activated carbons were obtained by activating wild cherry stones with different concentrations of phosphoric acid or zinc chloride at different temperatures. The adsorption of $N_2$ at 77 K and of $CO_2$ at 273 K was followed and the data were analyzes by considering different adsorption models. The activated carbons obtained measured high surface area with the most of the surface in all samples located in micropores. Fair agreement was found between the nitrogen surface areas calculated from the BET-, t-, ${\alpha}$- and DR- methods, although the first three are based on surface coverage whereas the latter is based on micropore filling. The carbon dioxide surface areas calculated by the DA equation were smaller than the comparable nitrogen areas. This was ascribed to domination of surface coverage mechanism, the absence of activated diffusion process. Based on this explanation the $CO_2$-surface areas as calculated by DA equation should be taken with great reservation.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2000년도 추계학술발표논문집 (하)
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• pp.1537-1540
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• 2000

MPLS 는 ATM 과 같은 기존의 레이어 2 계층의 스위칭 기술을 사용하여 IP와 같은 레이어 3 계층기능을 효과적으로 제공하기 위해서 제안되었다. 이러한 MPLS가 코어라우터에 적용될 때 확장성을 제공하기 위한 필수적인 방안으로 VC merging 기능이 요구된다. VC merging 기능은 수신된 ATM 셀들을 VCC 별로 AAL5 프레임 단위로 다중화하고 동일한 목적지를 갖는 ATM 셀에 대해서 동일한 VPI/VCI 값을 갖도록 ATM 셀을 생성한다. 본 논문에서는 최대 1Gbps 데이터를 처리하는 SAR 소자를 사용하여 VC merging 장치를 구현하였다. 그리고 이를 MPLS 망에 적용시키기 위해서 VCC 연결 설정에 제한성을 갖는 SAR 소자에도 적용 가능한 연결 설정 및 해제 절차를 제공하였다.

• Advances in Traditional Medicine
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• 제9권2호
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• pp.101-105
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• 2009

Morinda tinctoria Roxb. (Family: Rubiaceae) is commonly known as Indian mulberry or Aal in India. This plant is very well known for its therapeutic benefit in Indian systems of medicine including Ayurveda and Siddha and in other forms of traditional Medicine worldwide for the treatment of several ailments. Almost all parts of this plant have been explored for its medicinal uses. Several reports on the phytochemical and therapeutic benefits of this plant have been reported. In this article an attempt has been made to review the traditional uses, phytochemical profiles and therapeutic potentials of Indian mulberry.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2004년도 SMICS 2004 International Symposium on Maritime and Communication Sciences
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• pp.110-112
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• 2004

Poyethylene films can be modified by radiation grafting of N-vinyl pyrollidone using y-radiation. FTIR spectra were used to confirm the modification of PE films. The modified films were activated by two-step and one step methods for electroless Cu plating. Morphology of metallized films has been investigated. Electroless Cu plating onto the modified films depends mainly on the grafting degree and activation type. The conductivity of the metallized films has been investigated.

• 정보보호학회논문지
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• 제10권1호
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• pp.3-11
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• 2000

AAL-1에서는 (128, 124) Reed-Solomon부호를 사용한 인터리버 및 디인터리버에 의해 ATM 셀에서 발생하는 오류를 정정하고 있다. Reed-Solomon부호의 복호법 중 직접복호법은 오류위치다항식의 계산없이 오류위치와 오류치를 알 수 있으며 유한체 GF(2m)의 표현에서 정규기저를 사용하면 곱셈과 나눗셈을 단순한게 비트 이동만으로 처리할 수 있다. 직접복호법과 정규기저를 사용하여 ATM 적응계층에 적용 가능한 (128, 124) Reed-Solomon부호의 복호기를 설계하고 VHDL로 시뮬레이션 하였으며 이 복호기는 동일한 복호회로에 의해 둘 또는 하나의 심벌에 발생한 오류를 정정할 수 있다.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2002년도 가을 학술발표논문집 Vol.29 No.2 (3)
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• pp.133-135
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• 2002

ACE2000 MPLS 시스템은 대용량 ATM 교환 시스템인 ACE2000 ATM 교환시스템에 MPLS 기능을 부가함으로써 사용자들에게 차별화 된 서비스를 제공할 수 있는 시스템이다 MPLS 시스템에서는 채널 사용의 유연성과 채널 자원의 효율적인 사용을 위해 VC 머징 기능을 요구하고 있다. 이를 위해 ACE2000 MPLS 시스템에서는 출력 방향 패킷 처리기에 VC머징 기능을 구현하여 적용하고 있다. 구현된 VC 머징 장치는 고성능 SAR 소자를 이용하였다. VC 머징 장치는 ATM 셀 구조로 입력되고, 입력된 ATM 셀은 고성능 SAR 소자에 의해 AAL-5 유형의 패킷으로 변환되어 VC 머징 제어기로 입력된다. VC 머징 제어기에서는 패킷 입력부로부터 패킷을 받아들여 채널 연결 설정 정보에 따른 VC 머징 기능을 수행하도록 패킷을 처리한다. 이 VC 머징 제어기에서의 패킷 처리 시 스위치 포트의 Full Mesh 연결로 인해 발생되는 채널 자원의 감소 문제를 해결하고, 채널 자원을 증대시키기 위해 2 단계의 룩업 과정을 거치는 패킷 제어 기능을 수행한다. 패킷 제어기에 의해 처리된패킷은 또 하나의 고성능 SAR 소자로 구성되어 있는 패킷 출력부로 전달되어 셀 분할(Segmentation) 과정을 거쳐 ATM 형태로 다음 레이블 스위치 라우터로 전달 되도록 물리층 보드로 전달된다. 본 논문에서는 ATM 교환 시스템을 기반으로 MPLS 시스템에서 채널자원의 증대를 위한 출력방향 패킷 처리장치에 대하여 제안한다.

• Carbon letters
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• 제7권3호
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• pp.188-195
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• 2006

Phosphoric acid-activated carbon WP's and zinc chloride-activated carbons WZ's were developed from wild cherry stones. The textural properties of the activated carbons were determined from nitrogen adsorption data at 77 K and the chemistry of the carbon surface, i.e. the surface carbon-oxygen groups (type and amount) was determined from the base and acid neutralization capacities (Boehm method). The adsorption of phenol, p-nitrophenol, p-chlorophenol, dinitrophenol and dichlorophenol was followed at 298 K. The activated carbons obtained were characterized by high surface area and large pore volumes as well as by high surface concentration of C-O groups. The investigated carbons exhibited high adsorption capacities towards phenols with these capacities increased with the increase of molecular weight and the decrease of the solubility of phenol in water. However, no general relationship could be observed between the adsorption capacities of carbons and any of their textural parameters or their surface chemistry. This may be attributed to the many factors controlling phenol adsorption and the different types and mechanisms of adsorption involved.

• Coupled systems mechanics
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• 제9권5호
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• pp.433-454
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• 2020

In-place analysis for offshore platforms is essentially required to make proper design for new structures and true assessment for existing structures. The structural integrity of platform components under the maximum and minimum operating loads of environmental conditions is required for risk assessment and inspection plan development. In-place analyses have been executed to check that the structural member with all appurtenances robustness and capability to support the applied loads in either storm condition or operating condition. A nonlinear finite element analysis is adopted for the platform structure above the seabed and the pile-soil interaction to estimate the in-place behavior of a typical fixed offshore platform. The analysis includes interpretation of dynamic design parameters based on the available site-specific data, together with foundation design recommendations for in-place loading conditions. The SACS software is utilized to calculate the natural frequencies of the model and to obtain the response of platform joints according to in-place analysis then the stresses at selected members, as well as their nodal displacements. The directions of environmental loads and water depth variations have important effects on the results of the in-place analysis behavior. The result shows that the in-place analysis is quite crucial for safe design and operation of offshore platform and assessment for existing offshore structures.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 1998년도 Proceedings of International Workshop on Advanced Image Technology
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• pp.79-84
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• 1998

This paper describes implementation of the core DSM-CC UU interface. It briefly describes the reference model for the DSM-CC and related standards that should be reviewed for the implementation. The Common Object Request Broker Architechture, Revision 2.0 (CORBA 2.0) is sued as a remote procedure call (RPC) scheme for the UU Interface. Entire system was implemented with C++ on Windows NT platforms. The implementation procedure has been decomposed ito two tasks. The first task is to implement the Naming Service for service navigation. The Naming Service is one of the CORBA Services that extend the core CORBA specification. A client GUI is implemented for easy navigation among various services. The second task is to construct multimedia server and client for a Video-on-Demand (VoD) system. MPEG-2 Transport Stream is transported via ATM AAL5 using the Windows Socket 2.2 ATM extension API. A GUI enables the user to navigate the service domain and select a program. After the selection the user can control the MPEG-2 stream with VCR-like buttons.

• Steel and Composite Structures
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• 제42권2호
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• pp.209-219
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• 2022

Offshore platforms in seismically active areas must be designed to survive in the face of intense earthquakes without a global structural collapse. This paper scrutinizes the seismic performance of a newly designed and established jacket type offshore platform situated in the entrance of the Gulf of Suez region based on the API-RP2A normalized response spectra during seismic events. A nonlinear finite element model of a typical jacket type offshore platform is constructed taking into consideration the effect of structure-soil-interaction. Soil properties at the site were manipulated to generate the pile lateral soil properties in the form of load deflection curves, based on API-RP2A recommendations. Dynamic characteristics of the offshore platform, the response function, output power spectral density and transfer functions for different elements of the platform are discussed. The joints deflection and acceleration responses demands are presented. It is generally concluded that consideration of the interaction between structure, piles and soil leads to higher deflections and less stresses in platform elements due to soil elasticity, nonlinearity, and damping and leads to a more realistic platform design. The earthquake-based analysis for offshore platform structure is essential for the safe design and operation of offshore platforms.