• Title/Summary/Keyword: Code performance

Search Result 4,257, Processing Time 0.033 seconds

AN APPLICATION OF THE DETERMINATION METHOD FOR SOIL PARAMETERS WITH THE DESIGN CODE FOR PORT AND HARBOUR FACILITIES IN JAPAN

  • Watabe, Yoichi;Nozaki, Ikuro;Tanaka, Masanori;Kwon, Oh-Kyun
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2010.09c
    • /
    • pp.31-36
    • /
    • 2010
  • This paper introduces a practical determination method for soil parameters adopted in the new performance based design code for port and harbour facilities in Japan. In the new port-design code, the depth profile of the derived values is modeled as the profile of the estimated values so as to be either the mean value or the regression line, then the correction factors are multiplied to the estimated value according to the coefficient of variation (if COV > 0.1) and the number of the data entries (if n < 10). The new port-design code is applied to the unconfined compression test results for the Hiroshima Port clay in order to evaluate the undrained shear strengths. From the discussion, it is emphasized that not only the statistic treatment but also the engineering judgment are required in the procedure of the soil parameter determination for the reliability design.

  • PDF

Exact Error and Outage Probability Formulas for Alamouti Space Time Code 2 $\times$ J

  • Kong, Hyung-Yun;Khuong, Ho-Van;Nam, Doo-Hee
    • Journal of Communications and Networks
    • /
    • v.9 no.2
    • /
    • pp.177-184
    • /
    • 2007
  • Alamouti space-time code (STC) is a part of the UMTS-WCDMA standard. However, up to the best of our knowledge no exact closed-form outage and bit error probability (BEP) formulas for this famous code exists. Evaluating its performance through simulations is time-consuming and therefore, there should be analytical performance graphs to serve as a reference which are derived in this paper for coherently MPSK-modulated data. Additionally, analytical results take into account different channel fading levels from transmit antennas to receive ones.

Performance Comparison of Concatenated Codes with Different Inner Decoding Schemes in Frequency-Hopping Spread Spectrum Multiple-Access Channels (주파수 도약 대역확산 다중접속 채널에서 내 부호 복호화 기법에 따른 쇄상부호의 성능 비교)

  • Lee, Ye Hoon
    • Journal of Satellite, Information and Communications
    • /
    • v.9 no.2
    • /
    • pp.114-118
    • /
    • 2014
  • In this paper, we analyze the performance of a concatenated code with two different inner decoding schemes. One is the error-detecting inner decoding, and the other is the error-detecting-and-correcting inner decoding scheme. We compare the performances of the two decoding schemes for finite and infinite block length cases when the concatenated code is applied to slow frequency-hopping spread-spectrum multiple access (FH-SSMA) communication systems.

Analysis of GNSS Signal Acquisition Performance Spreading Zadoff-Chu Codes

  • Jo, Gwang Hee;Choi, Yun Sub;Lim, Deok Won;Lee, Sang Jeong
    • Journal of Positioning, Navigation, and Timing
    • /
    • v.8 no.1
    • /
    • pp.13-18
    • /
    • 2019
  • This paper analyzes the signal acquisition performance of the legacy GNSS spreading codes and a polyphase code. The code length and chip rate of a polyphase code are assumed to be same as those of the GPS L1 C/A and Galileo E1C codes. The autocorrelation and cross correlation characteristics are analyzed. In addition, a way to calculate a more accurate probability of false alarm for a code with sidelobe non-zero auto-correlation function is proposed. Finally, we estimate the probability of detection and the mean acquisition time for a given signal strength and the probability of false alarm.

Assessment of seismic design coefficients for composite special moment frames with reinforced concrete columns and steel beams: Evaluation of code recommendations

  • Elmira Tavasoli Yousef Abadi;Mohammad T. Kazemi
    • Steel and Composite Structures
    • /
    • v.50 no.6
    • /
    • pp.643-658
    • /
    • 2024
  • The main aim of this study is to quantify the code seismic design coefficients of the RCS system, which consisted of reinforced concrete columns and steel beams, based on the FEMA P-695 methodology. The underlying intention is to evaluate the seismic performance of the RCS system at the system level rather than the connection level. A set of 24 archetype buildings with a various number of stories, beam span lengths, gravity load levels, and seismic load levels are selected and designed based on the prevailing code requirements. Nonlinear analytical models are developed and validated by experimental tests. The pushover and response history dynamic analyses are conducted to evaluate the required data in the performance quantification process. The results show that the design coefficients suggested by the code are acceptable. However, the level of conservatism is very high. Thus, it is possible to use a larger R-factor in the design process or make some relaxations in the design requirements related to this structural system.

Expanding Code Caches for Embedded Java Systems using Client Ahead-Of-Time Compilation (내장형 자바 시스템을 위한 클라이언트 선행 컴파일 기법을 이용한 코드 캐시 확장)

  • Hong, Sung-Hyun;Kim, Jin-Chul;Shin, Jin-Woo;Kwon, Jin-Woo;Lee, Joo-Hwan;Moon, Soo-Mook
    • Journal of KIISE:Computing Practices and Letters
    • /
    • v.16 no.8
    • /
    • pp.868-872
    • /
    • 2010
  • Many embedded Java systems are equipped with limited memory, which can constrain the code cache size provided for Java just-in-time compilation, affecting the Java performance. This paper proposes expanding the limited code cache when it is full, by saving the machine code for some methods in the code cache into the file system of the permanent storage and reloading it to the code cache when they are re-invoked later. This is applying the client ahead-of-time compilation during the execution time for the purpose of enlarging the code cache. Our experimental results indicate that the proposed execution method can improve the performance by as much as 1.6 times compared to the conventional method, when the code cache size is reduced by half.

Robust Video Transmission System Employing Byte-Aligned Variable-Length Turbo Codes and Its Code-Rate Adaptation over Mobile Communication Channels (이동통신 환경에서 바이트 정렬 가변 길이 터보 코드의 적응 부호화율 적용을 통한 동영상 전송 시스템)

  • 이창우;김종원
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.29 no.7C
    • /
    • pp.921-930
    • /
    • 2004
  • In this paper, a robust video transmission system is proposed. To effectively prevent the corruption of video stream and its propagation in spatial and temporal domains, a version of turbo code, so-called as byte-aligned variable-length turbo code, is applied. Protection performance of the proposed turbo code is first evaluated by applying it to GOB-based variable-size ITU-T H.263+ video packets, where the protection level is statically controlled based on the joint source-channel criteria. This protection is then extended to support the adaptation of code ratio to best match the time-varying channel condition. The time-varying Rayleigh fading channel is modelled considering the correlation of the fading channel. The resulting performance comparison with the static turbo code as well as the conventional RCPC code clearly demonstrates the possibility of the proposed adaptation approach for the time-varying correlated Rayleigh-fading channel.

Scleral Diagnostic System Implementation with Color and Blood Vessel Sign Pattern Code Generations (컬러와 혈관징후패턴 코드 생성에 의한 공막진단시스템 구현)

  • Ryu, Kwang Ryol
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.18 no.12
    • /
    • pp.3029-3034
    • /
    • 2014
  • The paper describes the scleral diagnostic system implementation for human eyes by using the scleral color code and vessels sign pattern code generations. The system is based on the high performance DSP image signal processor, programmable gain control for preprocessing and RISC SD frames storage. RGB image signals are optimized by PGC, the edge image is detected form the gray image converted. The processing algorithms are executed by scleral color code generation and scleral vessels sign pattern code creation for discriminating and matching. The scleral symptomatic color code is generated by YCbCr values at memory map tolerated and the vessel sign pattern code is created by digitizing the 24 clock and 13 ring zones, overlay matching and tolerances. The experimental results for performance are that the system runs 40ms, and the color and pattern for diagnostic errors are around 20% and 24% on average. The system and technique enable a scleral diagnosis with subdividing the patterns and patient database.

A Sparse-ON Pixel Two-Dimensional 6/8 Modulation Code (저밀도 ON 픽셀 2차원 6/8 변조부호)

  • Hwang, Myungha;Lee, Jaejin
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.38A no.10
    • /
    • pp.833-837
    • /
    • 2013
  • Since holographic data storages read and write information on a volume and the information is processed per page, it has the advantage of high recording density and data transfer rate. However, there are two major drawbacks like 2-dimensional intersymbol interference and interpage interference as the density between pixels increases. Furthermore, a bright page that contains many ON pixels influences the reliable detection of the neighboring pages, which causes the less number of pages stored in the storage volume. We propose a sparse-ON pixel two-dimensional modulation code with the code rate 6/8 for increasing the number of pages stored in the volume. The proposed code is compared to conventional 6/8 balanced code, and it shows similar or a little bit better performance than that of the balanced code. Therefore, the proposed code can increase the recording capacity without loss of the performance.

A study on ACF Comparsion to Various Spreading Sequence for T-DMB Emergency Broadcasting (T-DMB 재난방송을 위한 다양한 확산 수열 자기상관특성 비교 연구)

  • Lee, Seung-Ho;Lee, Yong-Tae;Kim, Geon;Yang, Chung-Mo;Kim, Wan-Sik;Cho, Ju-Phil;Park, Yong-Woon;Cha, Jae-Sang
    • Journal of Satellite, Information and Communications
    • /
    • v.6 no.2
    • /
    • pp.125-130
    • /
    • 2011
  • In this paper, there was compared to the performance of the Auto Correlation Feature of each code using Spreading code for improving the data transmission technology in T-DMB disaster broadcasting. Generally, wireless mobile communication environment such as DMB occur the Inter Code Interference and the Multi-Path Interference in the process of the identification of the transmitter from the receiver. To solve this problem, spreading code technology was able to improve the security property. Also, it will be able to use in many fields of signal processing, because to control a period of the code can be variable. Therefore, in this paper, we studied to compare the performance of excellent orthogonal Golay code, Kasami code and ZCD(Zero Correlation Duration) code.