國際條約上의 紛爭에 관한 法律問題 考察

정해덕 경희대학교 국제법무대학원 1998 國際法務硏究 Vol.1 No.1

船荷證券上의 國際裁判管轄合意

丁海德 해상보험법연구회 2005 해상보험법연구 Vol.1 No.-

Steady-State Simulation of Long-Range Dependent Queuing Processes

정해덕 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.55 No.5

Long-range dependence was first noted in hydrology by H. E. Hurst from a study of the water levels of the Nile river which showed a tendency for a flood year to be followed by another flood year. Long-range dependent processes are relevant not only in telecommunication networks but also in such areas of scientific activity as econophysics, climatology, economics, environmental sciences, geology, geophysics, hydrology, computer science, and computer engineering. They provide good models of packet traffic in telecommunication networks, for example, in local area networks and video traffic, and good models of persistence analysis in econophysics, especially for short-term interest rates. In this paper, the effects of long-range dependence on the behaviors of queuing systems have been investigated. We have also investigated how the long-range dependence in arrival processes affects the length of sequential steady-state simulations being executed to obtain simulation results with the required level of statistical error. Our results show that the finite buffer overflow probability of a queuing system with a long-range dependent input is much greater than the equivalent queuing system with a Poisson or a short-range dependent input process and that the overflow probability increases as the Hurst parameter approaches one.

Fast Self-Similar Network Traffic Generation Based on FGN and Daubechies Wavelets

정해덕,이종숙,Jeong, Hae-Duck,Lee, Jong-Suk Korea Information Processing Society 2004 정보처리학회논문지 C : 정보통신,정보보안 Vol.11 No.5

최근의 통신 네트워크에서 teletraffic의 양상은 Poisson 프로세스보다 self-similar 프로세스에 의해서 더 잘 반영된다. 이는 통신 네트워크의 teletraffic에 관련하여 self-similar한 성질을 고려하지 않는다면, 통신 네트워크의 성능에 관한 결과는 부정확 할 수밖에 없다는 의미가 된다. 따라서, 통신 네트워크에 관한 시뮬레이션을 수행하기 위한 매우 중요한 요소 중에 하나는 충분히 긴 self-similar한 sequence를 얼마나 잘 생성하느냐의 문제이다. 본 논문에서는 fractional Gaussian noise와 wavelet 변환을 이용한 새로운 pseudo-random self-similar sequence 생성기를 구현 및 분석하였다. 특별히 본 생성기는 다른 wavelet 변환보다 long range dependent한 프로세스들의 self-similar 구조에 잘 맞기 때문에 좀더 정확한 결과를 유도할 수 있는 Daubechies wavelet을 사용하였다. 본 생성기를 이용하여 매우 긴 sequence를 생성하는데 요구되는 통계적인 정확도와 생성시간에 대해서 분석하였으며, 본 논문에서 제안한 생성기의 성능은 Hurst 변수의 상대적인 정확도로 보았을 때, 그리고 sequence의 생성시간을 고려했을 때에 매우 우수함을 보였다. 이 생성기의 이론적 complexity는 n개의 난수를 발생하는데 0(n)이 요구된다. Recent measurement studies of real teletraffic data in modern telecommunication networks have shown that self-similar (or fractal) processes may provide better models of teletraffic in modern telecommunication networks than Poisson processes. If this is not taken into account, it can lead to inaccurate conclusions about performance of telecommunication networks. Thus, an important requirement for conducting simulation studies of telecommunication networks is the ability to generate long synthetic stochastic self-similar sequences. A new generator of pseu-do-random self-similar sequences, based on the fractional Gaussian nois and a wavelet transform, is proposed and analysed in this paper. Specifically, this generator uses Daubechies wavelets. The motivation behind this selection of wavelets is that Daubechies wavelets lead to more accurate results by better matching the self-similar structure of long range dependent processes, than other types of wavelets. The statistical accuracy and time required to produce sequences of a given (long) length are experimentally studied. This generator shows a high level of accuracy of the output data (in the sense of the Hurst parameter) and is fast. Its theoretical algorithmic complexity is 0(n).

SrTiO₃첨가에 따른 (x)BaTiO₃-(1-x)SrTiO₃의 유전적, 전기적 특성

정해덕,장동환,김덕근,홍경진,최창주 木浦大學校 工業技術硏究所 1998 工業技術硏究誌 Vol.8 No.-

In this paper, a ferroelectric material BaTiO3 was added to SrTiO3, then (x)BaTiO3-(1-x)SrTiO3(0.7≤x≤1) ceramics were fabricated with stable electrical properties in high voltage. Microstructures and electrical properties were investigated according to mixing conditions of addition material SrTiO3. As a result of the investigation of all experiments, the shrinkage was excellent in 0.9BaTioO3-0.1SrTiO3. The grain size was increased, the curie temperature was shifted low temperature. The 0.9BaTiO3-0.1SrTiO3 was appeared stable property in temperature vs. permittivity. Also, 0.9BaTiO3-0.1SrTiO3 was showed stable dielectric properties at 25~85[C]. V-I properties of specimen were observed in the temperature range of 21~143[C], were divided into three regions. the region I below 10[kV/cm] was shown Ohmic conduction, the region II from 10 to 30[kV/cm] was explained by the poole-Frenkel emission theory and the region III above 30[kV/cm] was analysed by the tunneling effect.

전자빔 증착법으로 제작된 ZnS : Mn 박막의 구조 및 광학적 특성

정해덕,박계춘,이기식 ( Hae Duck Chung,Gye Choon Park,Ki Sik Lee ) 한국전기전자재료학회 1997 전기전자재료학회논문지 Vol.10 No.10

전자빔 증착법으로 제작된 ZnS:Mn 박막의 구조 및 광학적 특성

정해덕,박계춘,이기식 한국전기전자재료학회 1997 電氣電子材料學會誌 Vol.10 No.10

ZnS:Mn thin film was made by coevaporation with Electron Beam Evaparation(EBE) method. And structural and optical characteristics of ZnS:Mn thin films were investigated by substrate temperature annealing temperature and dopant Mn. When ZnS:Mn thin film was well deposited with cubic crystalline at substrate temperature of 30$0^{\circ}C$ its surface index was [111] and its lattice constant of a was 5.41$\AA$. Also When ZnA:Mn thin film was well made with hexagonal crystalline at substrate temperature of 30$0^{\circ}C$annealing temperature of 50$0^{\circ}C$and annealing time of 60min its miller indices were (0002) (1011), (1012) and (1120). And its lattice constant of a and c was 3.88$\AA$and 12.41$\AA$ respectively. Finally hexagonal ZnS:Mn thin film with dopant Mn of 0.5wt% had fundamental absorption wavelength of 342nm. And so its energy bandgap was about 3.62eV.

A Comparison of Three Fixed-Length Sequence Generators of Synthetic Self-Similar Network Traffic

정해덕,이종숙,Jeong, Hae-Duck J.,Lee, Jong-Suk R. Korea Information Processing Society 2003 정보처리학회논문지 C : 정보통신,정보보안 Vol.10 No.7

최근의 통신 네트워크에서 teletraffic의 양상은 Poisson 프로세스보다 self-similar프로세스에 의해서 더 잘 반영된다. 이는 통신 네트워크의 teletraffic에 관련하여 self-similar한 성질을 고려하지 않는다면, 통신 네트워크의 성능에 관한 결과는 부정확 할 수밖에 없다는 의미가 된다. 따라서, 통신 네트워크에 관한 시뮬레이션을 수행하기 위한 매우 중요한 요소 중에 하나는 충분히 긴 self-similar한 sequence를 얼마나 잘 생성하느냐의 문제이다. 본 논문에서는 FFT〔20〕, RMD〔12〕 그리고 SRA〔5, 10〕 방법을 이용한 세 개의 pseudo-random self-similar sequence 생성기를 비교 분석하였다. 본 Pseudo-random self-similar sequence 생성기의 성질을 매우 긴 sequence를 생성하는데 요구되는 통계적인 정확도와 생성시간에 대해서 분석하였다. 세 개의 pseudo-random self-similar sequence 생성기의 성능은 Hurst 변수의 상대적인 정확도로 보았을 때는 유사했으나, RMD와 SRA 방법을 이용한 pseudo-random self-similar sequence 생성기가 FFT 방법을 이용한 것보다 속도 면에서는 훨씬 빠른 것으로 나타났다. 또한 본 연구를 통해서 pseudo-random self-similar sequence 생성기의 비교분석을 위한 좀더 좋은 방법이 필요하다는 것을 보여주었다. It is generally accepted that self-similar (or fractal) processes may provide better models for teletraffic in modern telecommunication networks than Poisson Processes. If this is not taken into account, it can lead to inaccurate conclusions about performance of telecommunication networks. Thus, an important requirement for conducting simulation studies of telecommunication networks is the ability to generate long synthetic stochastic self-similar sequences. Three generators of pseudo-random self-similar sequences, based on the FFT〔20〕, RMD〔12〕 and SRA methods〔5, 10〕, are compared and analysed in this paper. Properties of these generators were experimentally studied in the sense of their statistical accuracy and times required to produce sequences of a given (long) length. While all three generators show similar levels of accuracy of the output data (in the sense of relative accuracy of the Horst parameter), the RMD- and SRA-based generators appear to be much faster than the generator based on FFT. Our results also show that a robust method for comparative studies of self-similarity in pseudo-random sequences is needed.

CuInS_2 박막 제조 및 그 특성

정해덕,박계춘,조재철,정운조,김성구 木浦大學校 工業技術硏究所 1992 工業技術硏究誌 Vol.2 No.-

The polycrystalline CuInS_2 thin films are prepared by vacuum heat treatment of layer, which is deposited by vaccum evaporation in order. The electrical and optical properties of the films are investigated at various sulfur deposition mole rate, substrate temperature, heat treatment temperature and time. From data, n type- CuInS_2 exhibits resistivity, transmittance and energy band gap with 142[Ωㆍ㎝], 73[%], and 1.5[eV] respectively at optimum fabrication condition. Finally, the films are fabricated with chalcopyrite structure.

사정변경으로 인한 용선계약의 해지가 가능한가?

정해덕 해상보험법연구회 2009 해상보험법연구 Vol.5 No.-