• 제목/요약/키워드: weak limit

검색결과 214건 처리시간 0.022초

뒤채움재로 점성토를 사용한 보강토벽의 내적 거동 분석 (An Analysis of the Internal Deformation Behaviors of Geosynthetic Reinforced Soil Walls used Clayey Soil as Backfills)

  • 김흥기;김유성
    • 한국지반환경공학회 논문집
    • /
    • 제6권2호
    • /
    • pp.39-49
    • /
    • 2005
  • 보강토벽의 안정성을 증명하고, 경제성의 극대화를 도모하기 위해, 본 연구에서는 뒤채움재로 현지 점성토를 사용하고 보강재로 부직포와 직포 그리고 부직포와 지오그리드를 혼합 배치하여 일반적인 한계평형해석으로는 안전율이 1.3미만인 2개의 실물 보강토벽을 얕은 연약지반 상에 구축하여 보강재, 수평토압, 그리고 간극수압 등의 거동을 약 15개월 동안 계측 및 분석하였다. 보강재의 길이를 보강토벽 높이의 30%로 설계하였고, 그에 따라 일반적인 한계평형해석에 의한 보강토벽의 안전율이 1.3미만 임에도 불구하고 2개의 실물보강토벽이 얕은 연약지반 상에 안전하게 구축되었고, 분석결과 보강재의 최대변형은 보강재의 특성에 따라 2.3~6.0%로 안전하고, 간극수압은 강우의 영향을 거의 받지 않는 것으로 나타났으나 수평토압은 안전율과 부등침하 등의 영향으로 보강토벽의 상 하부에서 주동토압과 정지토압보다 큰 것으로 나타났다.

  • PDF

8.2MHz 대역 미약 전계강도 무선기기의 출력기준에 관한 연구 (A Study on the Technical Regulation of Weak Electric Filed Strength Radio Equipment about 8.2Hz Frequency Band)

  • 김선엽;나유찬
    • 한국정보통신학회논문지
    • /
    • 제13권12호
    • /
    • pp.2498-2504
    • /
    • 2009
  • 본 논문에서는 8.2MHz 대역의 국내 미약 전계 강도 무선기기의 출력 제한치를 다른 외국의 기준치와 비교하였다. 이를 통해 국내의 규정이 미국이나 유럽에 비해 낮음을 대략 10-20dB 정도 낮음을 확인하였고, 이를 검증하기 위해 8.2MHz EAS 시스템의 출력을 측정하였다. 측정 결과, 전계 강도값이 각각 $70.6dB{\mu}V/m$$68.3dB{\mu}V/m$로 측정되었는데, 이러한 값은 국내의 현재기준인 $59.8dB{\mu}V/m$를 초과하는 값임을 확인하였다. 따라서 8.2MHz 대역의 국내기준의 사향 검토가 필요하다 사료된다.

철강구성(鐵鋼構成)이 톱밥보오드의 휨성질(性質)에 미치는 영향(影響) (Effects of the Wire Net Composition on Flexural Properties of Sawdustboard)

  • 이필우;서진석
    • Journal of the Korean Wood Science and Technology
    • /
    • 제13권4호
    • /
    • pp.67-72
    • /
    • 1985
  • To improve the bending strength of sawdustboard, verious resin contents of 10, 13, 16, and 19% were applied to the thin shell (face layer) composed with wire net or not. The shell effect of sawdust and wire net composition formed with core sawdustboard were evaluated. Forcusing on the effects of wire net composition and noncomposition including a comparison with chipboard and veneer complyboard, bending properties (Modulus of rupture (MOR), Modulus of elasticity (MOE), Stress at proportional limit ($S_{pl}$). Work to maximum load ($W_{ml}$))were analyzed and discussed. 1. In modulus of rutpute, veneer comply was the highest (621.5 kg/$cm^2$), and next decreasing order was wire net composition (159.1 kg/$cm^2$), chipboard (81.75 kg/$cm^2$), and wire net noncomposition (76.21 kg/$cm^2$) as in modulus of elasticity, work to maximum load, except for stress at proportional limit. 2. The highly significant effects were shown in both wire net composition and noncomposition, at the same time wire net composition exceeded two times of noncomposition throughout resin contents in bending properties. Chipboard was similar to the mean or 16% resin content in noncomposirion. 3. Every board in wire net composition above 10% resin content was beyond 100 kg/$cm^2$ in MOR, minimum allowable strength for structural use according to KS F 3104. In conclusion, the feasibility for improving the bending strength of weak sawdustboard by wire net composed shell was offered.

  • PDF

Adaptive SVM 기법 및 신뢰성 개념을 적용한 강관다단공법의 설계기법 연구 (Design of umbrella arch method based on adaptive SVM and reliability concept)

  • 이준석;사공명;박정준;최일윤
    • 한국터널지하공간학회 논문집
    • /
    • 제20권4호
    • /
    • pp.701-715
    • /
    • 2018
  • 본 연구에서는 터널주변 원지반의 불확실성을 고려한 신뢰성기반 강관다단공법의 설계기법에 대하여 논의하였다. 이를 위하여 기계학습기법의 한 부류인 adaptive support vector machine과 시공 중인 터널의 한계평형해석기법을 도입한 후, 강관다단공법을 적용한 터널의 안전성 여부에 대한 훈련과정을 최소화할 수 있는 방안을 제안하였다. 제안한 기법은 전형적인 Monte Carlo 기법과의 비교를 통해 그 효과를 분석하였다. 이 결과, 제안한 신뢰성기반 ASVM 기법은 원지반의 불확실성을 감안하는 경우, 보조공법 적용에 따른 터널의 시공 중 파괴확률을 효율적으로 계산할 수 있음을 입증하였다. 이 결과를 바탕으로 향후에는 한계평형해석을 적용할 수 없는 경우 등을 감안하여 최소의 수치해석 결과를 바탕으로 파괴확률을 추론해 낼 수 있는 신속 ASVM 기법을 개발할 예정이다.

성공적인 6차산업을 위한 가치사슬 모형과 빅데이터 활용 방안 (Value Chain Model and Big Data Utilization for a Successful the 6th Industry)

  • 박상혁;박정선;이명관
    • 디지털산업정보학회논문지
    • /
    • 제11권2호
    • /
    • pp.141-152
    • /
    • 2015
  • Our agriculture and rural villages have faced negative conditions in many reasons. To overcome this situation, a new change is needed by the 6th industrialization. Many agriculture and rural villages in Korea are pursuing the 6th industrialization through the convergence of the primary, secondary, and tertiary industries to vitalize agriculture and rural villages. But there are several problems with the 6th industrialization. There is a limit to the capacity building of the members of the rural organization and Korean agricultural base primary, secondary, and tertiary industries are weak all. In addition, it has been insufficient research for value chain management of the region as a whole; there has been no study of information sharing across the region for the 6th industrialization. This study is about value chain management model for successful the 6th industry with Quick Response System and the big data technology. In this study to provide the efficiency of 6th industry value chain management with customer's needs analysis using big data and research for the information share between the industries in the region through the information pipeline theory of the QR System. We hope that our study is helped to proceed successfully on the 6th industrialization in Korea.

임상진료지침 개발과정의 장애요인 - 심폐소생술을 중심으로 - (Barriers on Development of Clinical Practice Guidelines for Cardiopulmonary Resuscitation)

  • 박성희
    • 한국의료질향상학회지
    • /
    • 제7권1호
    • /
    • pp.46-58
    • /
    • 2000
  • Background : Despite favorable effects of guidelines on patient care, guidelines often fail to achieve their objectives. Poorly implemented medical practice guidelines can produce only weak effects on the process of health care delivery. Therefore, we performed this study to investigate barriers related development of clinical practice guidelines. Methods : Cardiopulmonary resuscitation was selected as a target problem. Self questionnaires about management of cardiopulmonary resuscitation were developed by a researcher with advisory 8 experts. The questionnaires were designed as a unstructured methods. The data were collected from March 1 to May 31, 1999. A total 50 death case admitted inpatient to Inha University Hospital were subjected to evaluate the development and application of clinical practice guidelines for cardiopulmonary resuscitation. The data were examined by frequency, t-test with SPSS. Result : The article reviewed several common barriers that might limit successful implementation of guidelines in clinical practice, as illustrated by evaluating recommendations for cardiopulmonary resuscitation clinical practice guidelines. Some major problems with guidelines were characterized as follows (1) ethical problem : euthanasia, (2) occurrence on various emergency event and setting, (3) non-medical problems (4) unreliable of medical record etc. Conclusion : Careful analysis of guideline attributes, anticipated effect on medical care, and organizational factors revealed several barriers to successful guideline implementation that should be addressed in the design of future guideline-based interventions.

  • PDF

신흡수용액을 이용한 중온수 흡수식 냉동기의 사이클 해석 (Cycle Analysis of Hot Water Driven Absorption Refrigerator with New Working Absorption Solution)

  • 권오경;윤재호;문춘근;윤정인
    • 대한기계학회논문집B
    • /
    • 제26권9호
    • /
    • pp.1241-1248
    • /
    • 2002
  • Performance extension of the absorption refrigerator with LiBr solution is often faced to operate very close to the crystallization limit. Especially in the development of an air-cooled cycle, the crystallization of working solution in the system is a very difficult problem to overcome. This paper describes the cycle of hot water driven absorption system using a new working absorption solution instead of LiBr solution to improve the efficiency. In this study, we found out the characteristics of new working absorption solution through the cycle simulation and compared LiBr solution to evaluate. The effect of cooling water temperature, weak solution flow rate, hot water temperature and hot water flow rate were also examined. The COP is increased 22% higher in the case of LiBr+Li1+LiC1+LiNO$_3$$H_2O$, 2% LiBr+HO(CH$_2$)$_3$OH+$H_2O$ than that of LiBr solution for the same operation condition.

수은 전극에서 루비안산의 전압-전류 거동 및 정량 (Voltammetric Behavior and Determination of Rubeanic acid at Mercury)

  • 권영순;구희진
    • 분석과학
    • /
    • 제10권3호
    • /
    • pp.216-224
    • /
    • 1997
  • 순환 전압-전류 그림에서 루비안산의 전기화학적 행동을 조사해 보면, 루비안산은 두 개의 환원 봉우리가 나타나는데, 첫번째 봉우리는 $S^{2-}$ 봉우리와 일치하므로 HgS 생성에 의한 환원 봉우리이며, 두번째 봉우리는 매우 약하며 확인되지 않았다. 시차 펄스 음극 벗김 전압-전류법으로 미량의 루비안산을 정량하는 방법을 고찰하였다. 루비안산의 정량을 위하여 pH 10.0, 붕산염 완충용액을 사용하였고, 최적 조건은 붕산염 완충용액의 농도 0.05M, 축적전위 -0.30V, 축적시간 120초, 그리고 주사속도 10mV/sec이다. 이 때 루비안산의 검출 한계는 $2.7{\times}10^{-8}M$이다.

  • PDF

모바일 로봇의 목표물 추적을 위한 이미지 궤환 제어 (A Image Feedback control of Mobile Robot for Target Tracking)

  • 황원준;이우송
    • 한국산업융합학회 논문집
    • /
    • 제18권2호
    • /
    • pp.90-98
    • /
    • 2015
  • This research propose with image-based visual a new approach to design a feedback control of mobile robot. because mobile robot must be recharged periodically, it is necessary to detect and move to docking station. Generally, laser scanner is used for detect of position of docking station. CCD Camera is also used for this purpose. In case of using camera, the position-based visual servoing method is widely used. But position-based visual servoing method requires the accurate calibration and it is hard and complex work. Another method using cameras is inmage-based visual feedback. Recently, image based visual feedback is widely used for robotic application. But it has a problem that cannot have linear trajectory in the 3-dimensional space. Because of this weak point, image-based visual servoing has a limit for real application. in case of 2-dimensional movement on the plane, it has also similar problem. In order to solve this problem, we point out the main reason of the problem of the resolved rate control method that has been generally used in the image-based visual servoing and we propose an image-based visual feedback method that can reduce the curved trajectory of mobile robot in th cartesian space.

창의성 증진을 위한 유추의 활용방법(1) - 상업공간 디자인과제를 중심으로 한 실험연구 - (A Study on Using Method of Analogy for Creativity Enhancement(1) - Experimental Study Focused on the Design Task of Commercial Space -)

  • 최은희
    • 한국실내디자인학회논문집
    • /
    • 제19권4호
    • /
    • pp.31-38
    • /
    • 2010
  • The objective of this study is to find a educational method that is able to increase creativity using both left and right directed thinking with complementary cooperation. The premise of experimental study is that analogical inference is a great help to make a creative design, and design tasks of commercial space, fashion shop and herb cafe are given to 25 students, voluntary participants in experimental tests. Tests make a clear distinction between a case using verbal analogy from many keywords and another case using verbal visual analogy from keywords and visual images. Consequently, when students use both verbal and visual analogy in solving design tasks their creative ability qualitatively as well as quantitatively is higher than in using verbal analogy. However, when students are classified with high and low sketching group verbal visual analogy is effective for students with high sketching ability to enhance both practicality and originality. Even students with low sketching ability can improve originality remarkably by using verbal visual analogy. In experiment there is time limit, a hour, but in actual studio class it is desirable that an educator guides the latter to make up for the weak points in practicality of their design taking time. Further study will be progressed with the design tasks of residential space to compare with the findings of this study.