• Title/Summary/Keyword: investigations

Search Result 4,874, Processing Time 0.034 seconds

A Study on Research Technique of the combustibles an Housing Facilities in Korea (국내 주거시설의 가연물 조사 기법에 관한 연구)

  • Shin, Yi-Chul;Kwon, Young-Jin
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
    • /
    • 2008.11a
    • /
    • pp.289-293
    • /
    • 2008
  • In performance-based on fire safety design of buildings, design fires are assumed to be relatively coarse information on potential combustible objects described by its name, weight, size and main constituent materials. As early as 1970s, researchers from Japan has employed various methods of research regarding combustibles investigations. In result, researchers came up with one method that is being presently used. Therefore, our country basis in collection of data for combustibles yielded average measure, receipt rate of furniture usage and execution of combustible investigations to occupancy zone of university respondents. We have found out problem about excessive usage of multi-outlet extensions through research.

  • PDF

Analysis of Slope Stability in Slopes of Failed and not Excavated (붕괴된 사면과 굴착되지 않은 사면의 안정성 검토)

  • 유병옥;김경석;이용희
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2003.06a
    • /
    • pp.129-144
    • /
    • 2003
  • Generally, investigation methods of cut slope are conducted only geological surface survey to gain engineering geological data of cut slopes. These methods have many problems such as limitations of investigation for a special area. So geophysical investigations such as geotomography, seismic and electrical resistivity methods have been used to search for failure surface in potential failure slopes or failed slopes. But investigation method using the borehole camera is recently a used method and it is thought that this method is more reliable method than other investigation methods because of being able to see by the eyes. Therefore, this paper was conducted investigations of borings and BIPS(Borehole Image Processing System) to search for potential sliding surfaces and was applied to obtain information of discontinuity on failed and potential failure slope in highway. As the results of BIPS, we could decide potential sliding surface in the slope, conducted to check slope stability and decided slope stability measures.

  • PDF

Experimental analysis on FEM definition of backfill-rectangular tank-fluid system

  • Cakir, Tufan;Livaoglu, Ramazan
    • Geomechanics and Engineering
    • /
    • v.5 no.2
    • /
    • pp.165-185
    • /
    • 2013
  • In the present study, the numerical and experimental investigations were performed on the backfill- exterior wall-fluid interaction systems in case of empty and full tanks. For this, firstly, the non-linear three dimensional (3D) finite element models were developed considering both backfill-wall and fluid-wall interactions, and modal analyses for these systems were carried out in order to acquire modal frequencies and mode shapes by means of ANSYS finite element structural analysis program. Secondly, a series of field tests were fulfilled to define their modal characteristics and to compare the results from proposed approximation in the selected structures. Finally, comparing the theoretical predictions from the finite element models to results from experimental measurements, a close agreement was found between theory and experiment. Thus, it can be easily stated that experimental verifications provide strong support for the finite element models and the proposed procedures themselves are the meritorious approximations to the real problem, and this makes the models appealing for use in further investigations.

DNA methylation-based age prediction from various tissues and body fluids

  • Jung, Sang-Eun;Shin, Kyoung-Jin;Lee, Hwan Young
    • BMB Reports
    • /
    • v.50 no.11
    • /
    • pp.546-553
    • /
    • 2017
  • Aging is a natural and gradual process in human life. It is influenced by heredity, environment, lifestyle, and disease. DNA methylation varies with age, and the ability to predict the age of donor using DNA from evidence materials at a crime scene is of considerable value in forensic investigations. Recently, many studies have reported age prediction models based on DNA methylation from various tissues and body fluids. Those models seem to be very promising because of their high prediction accuracies. In this review, the changes of age-associated DNA methylation and the age prediction models for various tissues and body fluids were examined, and then the applicability of the DNA methylation-based age prediction method to the forensic investigations was discussed. This will improve the understandings about DNA methylation markers and their potential to be used as biomarkers in the forensic field, as well as the clinical field.

Numerical investigations of tip clearance flow characteristics of a pumpjet propulsor

  • Lu, Lin;Gao, Yuefei;Li, Qiang;Du, Lin
    • International Journal of Naval Architecture and Ocean Engineering
    • /
    • v.10 no.3
    • /
    • pp.307-317
    • /
    • 2018
  • In this study, numerical investigations of the tip clearance flow characteristics of a pumpjet propulsor based on Computational Fluid Dynamics (CFD) method have been presented. The Zwart-Gerber-Belamri (Z-G-B) cavitation model based on Reynolds Averaged Navier-Stokes (RANS) method is employed. The structured gird is applied. The formation and development of the tip clearance flows has been investigated and presented. The structure of the tip leakage vortex has been shown. The radial distributions of different velocity components with different Span along the axial direction have been carried out to present the influence of the tip clearance flow on the main flow. In addition, the influences of the tip clearance size on the pumpjet propulsor performance, including the impact on the velocity flow fields and the cavitation characteristic, have been presented.

Modelling and experimental investigations on stepped beam with cavity for energy harvesting

  • Reddya, A. Rami;Umapathy, M.;Ezhilarasib, D.;Uma, G.
    • Smart Structures and Systems
    • /
    • v.16 no.4
    • /
    • pp.623-640
    • /
    • 2015
  • This paper presents techniques to harvest higher voltage from piezoelectric cantilever energy harvester by structural alteration. Three different energy harvesting structures are considered namely, stepped cantilever beam, stepped cantilever beam with rectangular and trapezoidal cavity. The analytical model of three energy harvesting structures are developed using Euler-Bernoulli beam theory. The thickness, position of the rectangular cavity and the taper angle of the trapezoidal cavity is found to shift the neutral axis away from the surface of the piezoelectric element which in turn increases the generated voltage. The performance of the energy harvesters is evaluated experimentally and is compared with regular piezoelectric cantilever energy harvester. The analytical and experimental investigations reveal that, the proposed energy harvesting structures generate higher output voltage as compared to the regular piezoelectric cantilever energy harvesting structure. This work suggests that through simple structural modifications higher energy can be harvested from the widely reported piezoelectric cantilever energy harvester.

Characterization of Pre-service Elementary Teachers' Scientific Reasoning in Experimental Design: Interaction between Knowledge and Reasoning (실험 설계에 나타난 초등 예비교사의 과학적 추론의 특징: 지식과 추론의 상호작용)

  • Jang, Byung-Ghi
    • Journal of Korean Elementary Science Education
    • /
    • v.31 no.2
    • /
    • pp.227-242
    • /
    • 2012
  • This research explores the scientific reasoning of pre-service elementary teachers in experimental design. The article focuses on pre-service teachers' responses to the questions in the worksheets which involve making their knowledge claims on extinguishing of a burning candle in a closed container, evaluating anomalous data, and designing experiment to test their ideas. Their responses are interpreted in terms of categories developed by Tytler and Peterson(2003, 2004). The interrelationship between conceptual knowledge and scientific reasoning is explored using the data. It is argued that coordination of ideas and evidence must be emphasized in the scientific investigations rather than fair test.