• 제목/요약/키워드: physical and mechanical characteristics

검색결과 841건 처리시간 0.03초

슬러지 및 안정화시킨 하수 슬러지의 물리적.역학적 특성 (Physical and Mechanical Properties of Waterwaste Sludge and Stabilized Sludge)

  • 송창섭
    • 한국농공학회지
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    • 제41권6호
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    • pp.97-104
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    • 1999
  • An experimental investigation was carried out to study the feasibility of using the stabiliozed sludge, as a backfill and cutoff-water materials for embankment structures. For stabilizing of sludge, hydrated lime and quick lime were used as additive, and a series of tests were performed on the sludge and the stabilized sludge to examine their physical and mechanical properties , compaction, compressive strength, hydraulic conuctivity and consolidation characteristics. From the test results, physical and mechanical properties of the stabilized sludge were improved as compared with the sludge. Especially from the viewpoint of physcial property, consolidation or settlement and cutoff-water, quick lime is more effective than the hydrated lime as a stabilization addtive. But, viewpoint of compaction and shear strength, hydrated lime is more effective than the quick lime as a atabilization additive. As a result of this study, it was found that the stabilized sludge can be developed the backfill and cutoff-water materials, improved the stabilizing method of sludge.

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The Effect of Atmospheric Conditions on the Physical and Mechanical Properties of Linerboard

  • Kim, Hyoung-Jin;Choi, Woo-Young;Um, Gi-Jeung
    • 펄프종이기술
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    • 제38권5호
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    • pp.60-65
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    • 2006
  • The physical and mechanical properties of linerboard were shown to be affected by changing atmospheric conditions. Two atmospheric conditions were measured in order to investigate how they were affected by different atmospheric conditions on the physical and mechanical properties of domestic linerboard. The basis data set for the standardization research was provided in this study. It is confirmed that the relative humidity seemed to be a major factor on the quality deterioration of a linerboard. Experimental results have shown that the short span compression test (SCT) could be used to evaluate the quality characteristics of linerboardat different moisture content and relative humidity.

Handle analysis of Cosmetic Textiles and its Correlation with Subjective haracteristics -Focus on puff textile-

  • Jung, Cheul Sun;Koo, Young Seok
    • 한국의류산업학회지
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    • 제16권2호
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    • pp.312-318
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    • 2014
  • This study examined the correlation between a handle evaluation of cosmetic puff textile and a sensory evaluation. The KES-F system was used to analyze the main mechanical factors for the handle evaluation and a statistical method was used for the sensory evaluation. The results revealed different mechanical properties and handle values of the tested cosmetic puff textiles. A material type and structure of the cosmetic textile affected the handle property of the material which is the most important factor for a cosmetic purpose. Particularly, the physical properties of textile material are likely to be important factors for the sensory property of cosmetic material. In addition, the sensory evaluation also revealed different sensory characteristics of the cosmetic efficiency according to the cosmetic puff textile. No close relationship was observed between the mechanical properties and sensory evaluation on the cosmetic puff textiles. The sensory evaluation of a cosmetic efficiency is not only decided by the physical and mechanical characteristics of the cosmetic textile material. Overall, when using textiles used for the cosmetic purposes, it is important to consider not only the proper mechanical properties of the textiles but also the use and sensory satisfaction. Development and selection of the cosmetic textiles should be focused on both the material function and consumer satisfaction.

요통 환자를 위한 멕켄지의 역학적 증후군 진단 : 역학적 부하 전략을 중심으로 (Diagnosis of McKenzie Mechanical Syndromes for Patient with Low Back Pain : Focused on mechanical loading strategies)

  • 김민희
    • 정형스포츠물리치료학회지
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    • 제14권2호
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    • pp.109-115
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    • 2018
  • Purpose: McKenzie is a widely-used and conventional clinical therapeutic exercise for patients with mechanical lower back pain. It is a well-designed assessment and classification system for the spine. Main issue: Patients with mechanical lower back pain are classified into one of three mechanical syndromes (posture, dysfunction, or derangement syndrome) by mechanical loading strategies. These methods evaluate symptomatic and mechanical responses during repeated end-range movement and sustained postures. The goal of McKenzie mechanical syndrome diagnosis is to determine directional preferences. Directional preference is a phenomenon of preference for posture or movement in one direction, which reduces or centralizes pain. However, in Korea, there is a lack of awareness of basic McKenzie mechanical syndromes diagnostic concepts. Koreans tend to think of the McKenzie method as a simple lumbar extension exercise. However, an accurate diagnosis of a mechanical syndrome must precede the application of McKenzie exercise. Conclusions: Thus, in this study, I present a classification method of McKenzie mechanical syndrome diagnosis and clinical characteristics of each mechanical syndrome.

Probabilistic dynamic analysis of truss structures

  • Chen, J.J.;Che, J.W.;Sun, H.A.;Ma, H.B.;Cui, M.T.
    • Structural Engineering and Mechanics
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    • 제13권2호
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    • pp.231-239
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    • 2002
  • The problem of dynamic analysis of truss structures based on probability is studied in this paper. Considering the randomness of both physical parameters (elastic module and mass density) of structural materials and geometric dimension of bars respectively or simultaneously, the stiffness and mass matrixes of the elements and structure have been built. The structure dynamic characteristic based on probability is analyzed, and the expressions of numeral characteristics of inherence frequency random variable are derived from the Rayleigh's quotient. The method of structural dynamic analysis based on probability is developed. Finally, two examples are given.

Mechanical deterioration and thermal deformations of high-temperature-treated coal with evaluations by EMR

  • Biao Kong;Sixiang Zhu;Wenrui Zhang;Xiaolei Sun;Wei Lu;Yankun Ma
    • Geomechanics and Engineering
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    • 제32권2호
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    • pp.233-244
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    • 2023
  • With the increasing amount of resources required by the society development, mining operations go deeper, which raises the requirements of studying the effects of temperature on the physical and mechanical properties of coal and adjacent rock. For now, these effects are yet to be fully revealed. In this paper, a mechanical-electromagnetic radiation (EMR) test system was established to understand the mechanical deterioration characteristics of coal by the effect of thermal treatment and its deformation and fracture characteristics under thermo-mechanical coupling conditions. The mechanical properties of high-temperature-treated coal were analyzed and recorded, based on which, reasons of coal mechanical deterioration as well as the damage parameters were obtained. Changes of the EMR time series under unconstrained conditions were further analyzed before characteristics of EMR signals under different damage conditions were obtained. The evolution process of thermal damage and deformation of coal was then analyzed through the frequency spectrum of EMR. In the end, based on the time-frequency variation characteristics of EMR, a method of determining combustion zones within the underground gasification area and combustion zones' stability level was proposed.

Determination of homogeneity index of cementitious composites produced with eps beads by image processing techniques

  • Comak, Bekir;Aykanat, Batuhan;Bideci, Ozlem Salli;Bideci, Alper
    • Computers and Concrete
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    • 제29권2호
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    • pp.107-115
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    • 2022
  • With the improvements in computer technologies, utilization of image processing techniques has increased in many areas (such as medicine, defence industry, other industries etc.) Many different image processing techniques are used for surface analysis, detection of manufacturing defects, and determination of physical and mechanical characteristics of composite materials. In this study, cementitious composites were obtained by addition of Grounded Granulated Blast-Furnace Slag (GGBFS), Styrene Butadiene polymer (SBR), and Grounded Granulated Blast-Furnace Slag and Styrene Butadiene polymer together (GGBFS+SBR). Expanded Polystyrene (EPS) beads were added to these cementitious composites in different ratios (20%, 40% and 60%). The mechanical and physical characteristics of the composites were determined, and homogeneity indexes of the composites were determined by image processing techniques to determine EPS distribution forms in them. Physical and mechanical characteristics of the produced samples were obtained by applying consistency, density, water absorption, compressive strength (7 and 28 days), flexural strength (7 and 28 days) and tensile splitting strength (7 and 28 days) tests on them. Also, visual examination by using digital microscope, and image analysis by using image processing techniques with open source coded ImageJ program were performed. As a result of the study, it is determined that GGBFS and SBR addition strengthens the adhesion sites formed as it increases the adhesion power of the mixture and helps to get rid of the segregation problem caused by EPS. As a result of the image processing analysis it is demonstrated that GGBFS and SBR addition has positive contribution on homogeneity index.

군용 및 산자용 나일론 고강력 태섬사 및 후직물의 물성 분석 (Analysis on the Physical Property of Nylon High Tenacity Coarse Yarn and Fabric for Military and Technical Textiles)

  • 김승진;김상룡;이도현;최우혁
    • 한국염색가공학회지
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    • 제21권3호
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    • pp.43-48
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    • 2009
  • This paper surveys the mechanical properties of nylon high tenacity coarse yarn and fabric for military and technical textiles. For this purpose, 6 kinds of yarns and 2 kinds of fabrics are prepared. The yarn physical properties such as yarn count, thermal shrinkages, and tensile properties are measured and discussed with the characteristics of the domestic and imported yarns. And, the physical and mechanical properties of these fabrics are also measured and discussed with the usage of these fabrics in the military and technical textiles fields. Hereafter, the differences of physical properties between domestic and foreign yarn specimens for high functional military and technical fabrics are estimated through this study.

Evaluation of energy release rate of composites laminated with finite element method

  • Achache, Habib;Boutabout, Benali;Benzerdjeb, Abdelouahab;Ouinas, Djamel
    • Structural Engineering and Mechanics
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    • 제55권1호
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    • pp.191-204
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    • 2015
  • Control of the mechanical behavior of composite materials and structures under monotonic and dynamic loads for cracks and damage is a vast and complex area of research. The modeling of the different physical phenomena and behavior characteristics of a composite material during deformation play an important role in the structural design. Our study aims to analyze numerically the energy release rate parameter G of a composite laminated plate (glass or boron / epoxy) cross-ply [$+{\alpha}$, $-{\alpha}$] in the presence of a crack between two circular notches under the effect of several parameters such as fiber orientation ${\alpha}$, the crack orientation ${\beta}$, the orientation ${\gamma}$ of the two considered circular notches and the effect of mechanical properties. Our results show clearly that both notches orientation has more effect on G than the cracks and fibers orientations.

무전해 니켈도금에 대하여(II) (Electroless Nickel Plating)

  • 지태촌;여운관
    • 한국표면공학회지
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    • 제15권2호
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    • pp.57-67
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    • 1982
  • Electroless Ni-plating is often utilized in industries due to its physical and mechanical characteristics in contrast to conventional electroplatings. Thus, electroless Ni-plating will be broadly applicated in many fields. However, The physial and mechanical properties of this depositss depend largely on the structure and P content of film and heat treatment. And here discused about the important results of those past research.

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