• Title/Summary/Keyword: Logging

Search Result 679, Processing Time 0.022 seconds

A Bayesian Approach to Geophysical Inverse Problems (베이지안 방식에 의한 지구물리 역산 문제의 접근)

  • Oh Seokhoon;Chung Seung-Hwan;Kwon Byung-Doo;Lee Heuisoon;Jung Ho Jun;Lee Duk Kee
    • Geophysics and Geophysical Exploration
    • /
    • v.5 no.4
    • /
    • pp.262-271
    • /
    • 2002
  • This study presents a practical procedure for the Bayesian inversion of geophysical data. We have applied geostatistical techniques for the acquisition of prior model information, then the Markov Chain Monte Carlo (MCMC) method was adopted to infer the characteristics of the marginal distributions of model parameters. For the Bayesian inversion of dipole-dipole array resistivity data, we have used the indicator kriging and simulation techniques to generate cumulative density functions from Schlumberger array resistivity data and well logging data, and obtained prior information by cokriging and simulations from covariogram models. The indicator approach makes it possible to incorporate non-parametric information into the probabilistic density function. We have also adopted the MCMC approach, based on Gibbs sampling, to examine the characteristics of a posteriori probability density function and the marginal distribution of each parameter.

EMG assessment of Muscle Fatigue on Sloping Ground When Lifting (EMG를 이용한 경사면에서의 근피로도 분석)

  • 서승록;김종석
    • Journal of Korea Society of Industrial Information Systems
    • /
    • v.5 no.2
    • /
    • pp.1-8
    • /
    • 2000
  • Manual material handling(MMH)is major factor which causing physical injuries of worker at working area and frequency of low back pain(LBP) is increasing industrial accidents. Especially, working in bad circumstance such as farm, orchard, harbor loading and unloading, logging place and mining place which located in inclined slope can cause much possibility of hazard and absence of working balance can cause injuries of musculoskeletal system such as joint, bone, ligament. So, this study used EMG system to measure and evaluate muscle force information and fatigue of worker when lifting on slope. The result of measuring averaged integrated EMG(AEMG) shows multifidus muscle be used more than anything else in force. neck extensors are used at 15°, 20°frequently. generally the AEMG result shows multifidus muscle be used in force. Commonly, muscle fatigue of multifidus is higher than other muscle by analysis mean power frequency(MPF). The result of load sharing rate shows multifidus and erectorspinae which are deep spinal muscles is relatively high and neck extensor is low.

  • PDF

Televiewer Rock Strength as an Approach to Estimate the Strength of in situ Rocks (텔레뷰어 암석강도 산출 및 그의 응용성)

  • 김중열;김유성;현혜자
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2002.03a
    • /
    • pp.237-244
    • /
    • 2002
  • Televiewer is a logging tool capable of scanning the borehole wall. The tool uses a rotating acoustic beam generator that acts as both a transmitter and receiver. The beams are sent toward the wall. The amplitude of a returning signal from the wall has nearly a linear relationship with the reflection coefficient R of the borehole wall, when the wall is smooth. As R depends only on rock impedance for fixed water impedance, the amplitude is directly associated with mass density and seismic velocity of rock. Meanwhile, the amplitude can be further reduced by wall roughness that may be caused by drilling procedures, differences in rock hardness, because the rough surface can easily scatter the acoustic energy and sometimes the hole becomes elongated in all directions according to the degree of weathering. In this sense, the amplitude is related to the hardness of rocks. For convenience of analysis, the measured amplitude image(2-D data(azimuth ${\times}$ depth)) is converted, with an appropriate algorithm, to the 1-D data(depth), where the amplitude image values along a predetermined fracture signature(sinusoid) are summed up and averaged. The resulting values are subsequently scaled simply by a scalar factor that is possibly consistent with a known strength. This scaled Televiewer reflectivity is named, as a matter of convenience,“Televiewer rock strength”. This paper shows, based on abundant representative case studies from about 8 years of Televiewer surveys, that Televiewer rock strength might be regarded, on a continuous basis with depth, as a quitely robust indicator of rock classification and in most cases as an approximate uniaxial strength that is comparable to the rebound value from Schmidt hammer test.

  • PDF

Use of Ultrasonic beam transmissivity for investigating the structural features in plastic pipe cased borehole (초음파의 매질 투과성을 이용한 시추공 케이싱 배면의 암상 및 절리구조 조사 연구)

  • 김중열;김유성
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2002.03a
    • /
    • pp.751-758
    • /
    • 2002
  • Boreholes that are drilled in soft or unconsolidated materials such as gravels and coals are prone to collapse. To maintain the hole, some kinds of casing pipes are needed. If thereby a plastic pipe e.g. PVC is used for the casing, Televiewer tool is still capable of detecting structural features such as fractures in the borehole wall behind the pipe, whereas other borehole-imaging logging devices such as BIPS (Borehole Image Processing System) and FMS(Formation Micro Scanner) won't provide any information about that. Televiewer's primary component is a piezoelectric transducer centered in the hole. It acts as both a transmitter and receiver, and sends an ultrasonic beam. That is reflected, in the same manner as the seismic wave propagation, from the both sides(inner and outer surfaces) of the casing pipe, transmits through the pipe and then reflected from the borehole wall. With an appropriate choice of time-windowing, it is possible to capture the returning signals from both the borehole wall and the outer side of casing pipe as well. A suite of laboratory tests were performed on various physical models composed of plastic pipes with different diameters. Although the amplitudes of returning signals were reduced to about half the usual value due to the transmission loss, the dynamic range of Televiewer tool was sufficient to observe the structural features behind the casing pipe. Besides, several representative case studies at various research areas in our country are presented. The results demonstrate the usefulness of the transmissivity of Televiewer acoustic km, which will assist in further structural interpretation.

  • PDF

A Pilot Study of In-hole Seismic Method (인홀탄성파시험의 타당성 연구)

  • Mok, Young-Jin;Kim, Jung-Han;Kang, Byung-Soo
    • Journal of the Korean Geotechnical Society
    • /
    • v.19 no.3
    • /
    • pp.23-31
    • /
    • 2003
  • Over the past half century, borehole seismic surveys have been diversified into the three techniques such as crosshole, downhole, and suspension logging according to their devices and testing configurations. These field techniques have been improved, in terms of equipment and testing procedures, and are very valuable in the evaluation of ground characteristics for geotechnical and earthquake engineering problems. Yet, despite the importance and significance of the techniques as engineering tools, the techniques are not much used as standard penetration test (SPT) by practicing engineers. The possible explanations are cost and operational difficulties of the surveys as well as sophistication and complexity of the devices. An in-hole seismic method has been developed to meet the requirement of economical testing cost and practicality in engineering practice to measure dynamic soil properties. The prototype in-hole probe developed herein is small and light enough to be fit in three-inch boreholes and to be handled with bare hands. The performance of the source has been evaluated through extensive crosshole tests at various sites. The in-hole seismic method was adopted at three test sites and verified by comparing with crosshole results.

Mobile Payment System Design with Transaction Certificate Mode (거래 인증 모드를 사용한 이동 결제 시스템 설계)

  • Sung, Soon-Hwa;Ryou, Jae-Cheol
    • Journal of the Korea Institute of Information Security & Cryptology
    • /
    • v.24 no.5
    • /
    • pp.931-939
    • /
    • 2014
  • The Web or Mobile channel of previous Web access authentication system for a payment only provides the authentication of remote users, and does not provide the authentication between a user and a bank/financial institution. Therefore, this paper proposes the Transaction Certificate Mode(TCM) for a payment which can preserve the mutual authentication between a user and a bank/financial institution for Web-based payment systems. The proposed system has designed for wireless network instead of Secure Electronic Transaction (SET) designed for wired electronic transaction. In addition, this system with TCM is able to support an account-based transaction for wireless networks instead of a disadvantage of SET such as a card-based transaction for wired networks. Therefore, customers can check their balances without logging on their bank's web site again due to mutual authentication between a customer and his bank/financial institution.

Compound Backup Technique using Hot-Cold Data Classification in the Distributed Memory System (분산메모리시스템에서의 핫콜드 데이터 분류를 이용한 복합 백업 기법)

  • Kim, Woo Chur;Min, Dong Hee;Hong, Ji Man
    • Smart Media Journal
    • /
    • v.4 no.3
    • /
    • pp.16-23
    • /
    • 2015
  • As the IT technology advances, data processing system is required to handle and process large amounts of data. However, the existing On-Disk system has limit to process data which increase rapidly. For that reason, the In-Memory system is being used which saves and manages data on the fast memory not saving data into hard disk. Although it has fast processing capability, it is necessary to use the fault tolerance techniques in the In-Memory system because it has a risk of data loss due to volatility which is one of the memory characteristics. These fault tolerance techniques lead to performance degradation of In-Memory system. In this paper, we classify the data into Hot and Cold data in consideration of the data usage characteristics in the In-Memory system and propose compound backup technique to ensure data persistence. The proposed technique increases the persistence and improves performance degradation.

The Implementation of Integrated Information Network for JANG-MOK Oceanographic Research Ship (시험조사선 장목호의 종합정보통신망 구현)

  • Park Jong-Won;Kim Dug-Jin;Baek Hyuk;Park Dong-Won
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2006.05a
    • /
    • pp.91-94
    • /
    • 2006
  • KORDI(Korea Ocean Research & Development Institute) built a research vessel JANG-MOK with 40 G/T for a survey and observation of oceanographic environmental characteristics at coastal region in September 2005. This paper introduced the implementation for hardware and software of an integrated information network that loaded in JANG-MOK, and depicted the function of an integrated information network, such as an installation of ga-bit based network, RS232C serial & UDP network interface of instruments, a data logging software of measured data, Hawkeye II software for supporting the efficient survey works, and a real-time navigation viewer. In addition, we presents the another implementation method for an integrated information network of oceanographic research vessels.

  • PDF

Design of User Integrated Authentication System in Heterogeneous Distributed Cloud Service Brokerage Environment (이종 분산 클라우드 서비스 브로커리지 환경에서의 사용자 통합 인증 시스템 설계)

  • Lee, Daesung
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.20 no.11
    • /
    • pp.2061-2066
    • /
    • 2016
  • Currently, cloud systems are not interoperable due to low interoperability between cloud systems as operators build up cloud environments with their own way. For example, users of the Google cloud system can not use the Microsoft (Microsoft) cloud system unless they go through an additional log-in process. In order for Google cloud system's users to use MS cloud system services, they must log in to the MS cloud system again after logging out of Google cloud system. In order to solve these problems, Cloud Service Broker(CSB) technology has emerged to resolve the interoperability problem between cloud systems, but many researches and developments are still needed. In this paper, we design an integrated user authentication system, which is a fundamental problem of cloud user interoperability among CSB (Cloud Service Broker) technologies, which is emerging as a service intervention technology of heterogeneous distributed cloud environment.

Development of Secure Entrance System using AOP and Design Pattern (관점지향 소프트웨어 개발 방법론과 디자인 패턴을 적용한 출입 보안 시스템 개발)

  • Kim, Tae-Ho;Cheon, Hyeon-Jae;Lee, Hong-Chul
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.11 no.3
    • /
    • pp.943-950
    • /
    • 2010
  • A secure entrance system is complicated because it should have various functions like monitoring, logging, tracing, authentication, authorization, staff locating, managing staff enter-and-leave, and gate control. In this paper, we built and applied a secure entrance system for a domestic nuclear plant using Aspect Oriented Programming(AOP) and design pattern. Using AOP has an advantage of clearly distinguishing the role for each functional module because building a system separated independently from the system's business logic and security logic is possible. It can manage system alternation flexibility by frequent change of external environment, building a more flexible system based on increased code reuse, efficient functioning is possible which is an original advantage of AOP. Using design pattern enables to design by structuring the complicated problems that arise in general software development. Therefore, the safety of the system can also be guaranteed.