• Structural Engineering and Mechanics
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• 제5권6호
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• pp.817-837
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• 1997

In the present contribution an interface crack model is introduced which is capable of modelling crack initialisation and growth in aluminium as well as in Fibre Metal Laminates. Interface elements are inserted in a finite element mesh with a yield function which bounds all states of stress in the interface. Hardening occurs after a state of stress exceeds the yield stress of the material. The hardening branch is bounded by the ultimate stress of the material. Thereafter, the state of stress is reduced to zero while the inelastic deformations grow. The energy dissipated by the inelastic deformations in this process equals the fracture energy of the material. The model is applied to calculate the onset and growth of cracking in centre cracked plates made of aluminium and GLARE$^{(R)}$. The impact of the model parameters on the performance of the crack model is studied by comparisons of the numerical results with experimental data.

• Advances in concrete construction
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• 제7권4호
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• pp.249-262
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• 2019

In this study, high strength aluminum alloys (AA) plates are proposed as a new construction material for strengthening reinforced concrete (RC) beams. The purpose of this investigation is to evaluate AA plate's suitability as externally bonded reinforcing (EBR) materials for retrofitting shear deficient beams. A total of twenty RC beams designed to fail in shear were strengthened with different spacing and orientations. The specimens were loaded with four-points loading till failure. The considered outcome parameters included load carrying capacity, deflection, strain in plates, and failure modes. The results of all tested beams showed an increase up to 37% in the load carrying capacity and also an increase in deflection compared to the control un-strengthened beams. This demonstrated the potential of adopting AA plates as EBR material. Finally, the shear contribution from the AA plates was predicted using the models available in the ACI440-08, TR55 and FIB14 design code for fiber reinforced polymer (FRP) plates. The predicted results were compared to experimental testing data with the ratio of the experimentally measured ultimate load to predicted load, range on the average, between 93% and 97%.

• Journal of Biosystems Engineering
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• 제35권4호
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• pp.250-256
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• 2010

This study is conducted to analyze the drying characteristics of domestically produced Lycii Fructus for improving drying conditions which was dependant on the shape and materials of drying plate. The materials of the drying plates were steel, aluminum and ABS resin, and each plate was shaped semicircle, quadrangular pyramid, and triangle pyramid. Also, mesh plate, the most general type was included. In other words, 10 kinds of plates were made and tested. The test was conducted at $45^{\circ}C$, for 24 hours and moisture content was measured every 4 hours. The quality of tested Lycii Fructus was measured by colorimeter after drying. The experimental results show that regardless of species of Lycii Fructus, the drying rate of the aluminium plate shaped quadrangular pyramid was fastest, 3.11%w.b./h. Except the mesh plate, the drying rate of most plates was about over 2.52%w.b./h. The quality of Lycii Fructus dried on the aluminium plate shaped quadrangular pyramid was the highest, and it was easiest to separate the dried Lycii Fructus from the aluminum plate shaped quadrangular pyramid.

• 대한방사선기술학회지:방사선기술과학
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• 제4권1호
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• pp.63-71
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• 1981

The metal-plates(Aluminium. Copper, Lead) of change the variation thickness have been penetrated by the collimated beam($450mm{\times}4mm{\phi}$) of Gamma-ray from $^{192}Ir$. Then, the scattered $\gamma$-ray dose in variable angle and the directly transmitted $\gamma$-ray dose were measured using the electrometer of ionization chamber. The results were summarized as follows: 1. Obtained the mass attenuation coefficients of $Al;0.0937cm^2g^{-1},\;Cu;0.0937cm^2g^{-1},\;pb;0.244cm^2g^{-1}$. 2. Total intensity of front scattered $\gamma$-ray follow the order of Al>Cu>pb. 3. The scattered $\gamma$-ray intensity with the lager angle of scattering was saturated after increase rapidly, and the scattering angle of the more larger was decreased. 4. The scattered $\gamma$-ray intensity through plates of aluminium or copper was saturated after increase with thicker scatterer, and the intensity was decreased at the more thicker. But the variation of scattered $\gamma$-ray dose in the lead plate made the fewest than Al and Cu. 5. The ratio of the scattered $\gamma$-ray dose and the directly transmitted $\gamma$-ray dose was saturated after increase with the thicker scatterer, and the scatterer of the more thicker was decreased. Degree of total intensity in these ratios was followed the order of Cu>Al>Pb.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 1997년도 특별강연 및 추계학술발표 개요집
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• pp.184-193
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• 1997

Aluminium and aluminium alloys have the high electrical and heat conductivity. It gives rise to difficulties for a choice of electrodes material for their contact electric welding. This paper describes the investigations performed to solve the above problem. The purpose of this investigation was to obtain dispersion-hardening alloys by the internal oxidation method, to optimize their contents and treatment modes, to produce electrodes of these alloys and to test them. The strengthing effect of alloys with oxide particles depends on their size stability at high temperatures. Despite of the fact, that oxides are the most stable of all the non-metallic phases their coagulation takes place. Based on the early results, we chose two types of alloys, first No. 1 Cu - 0,4%Al and second No. 2 Cu - 0,2%Be for production of electrodes. These alloys had not additional alloying elements. These alloys were prepared as 1 mm plates and flake-formed 200 m thick, and also No. 1 as a powder of size 100 mkm (received from Korea). The large samples for electrodes were produced by three methods : explosive welding method, dynamic one including the explosion compression of electrode blank and the quasi-dynamic method including the high-speed compression of dense briquest and the further hot extrusion of a rod.

• Earthquakes and Structures
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• 제15권3호
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• pp.285-294
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• 2018

In this study, nonlinear dynamic response of a concrete plate retrofit with Aluminium oxide ($Al_2O_3$) under seismic load and magnetic field is investigated. The plate is a composite reinforced by Aluminium oxide with characteristics of the equivalent composite being determined using Mori-Tanka model considering agglomeration effect. The plate is simulated with higher order shear deformation plate model. Employing nonlinear strains-displacements, stress-strain, the energy equations of column was obtained and using Hamilton's principal, the governing equations were derived. Differential quadrature method (DQM) in conjunction with Newark method is applied for obtaining the dynamic response of structure. The influences of magnetic field, volume percent of nanoparticles, geometrical parameters of column, agglomeration and boundary conditions on the dynamic response were investigated. Results showed that with increasing volume percent of nanoparticles, the dynamic deflection decreases.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2004년도 가을 학술발표회 논문집
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• pp.110-117
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• 2004

The aim of a benchmark study is carried out nine methods are employed for ULS analysis which implicitly predict the ultimate strength of aluminium stiffened panels under axial compression. For this purpose, DNV PULS, experimental and numerical data on the ultimate strength of panels were collected. Comparison of these experimental / numerical, DNV PULS / numerical, results with theoretical solutions by the candidate methods is performed. Also it's compared that ALPS/ULSAP program is based on closed-form formula for the ULS of plates and grillages under axial compression. It is considered that ALPS/ULSAP methodology provides quite accurate and reasonable ULS calculations by a comparison with more refined FEA. Comparison of these experimental data, numerical, computational software results with the simplified solutions obtained by the candidate methods is then performed. The model uncertainties associated with the candidate methods are studied in terms of mean bias and COV (i.e., coefficient of variation) against experiments and numerical solutions, and the relative performance of the various methods is discussed.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 춘계학술대회 논문요약집
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• pp.174-174
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• 2004

본 논문에서는 4변이 고정된 정사각형 알루미늄 평판의 진동 진폭을 측정하기 위하여, 기존의 위상 이동 ESP떼 스트로보스코프식 조사를 적용한 스트로보스코픽 ESPI 기법을 이용하였다. 일반적으로 시간평균 ESPI를 이용하면 진동하고 있는 대상체의 정성적인 진동 패턴을 측정할 수 있다. 그러나 시간평균 ESPI로는 진동하고 있는 대상체의 두께방향으로의 진폭량을 측정하기는 어렵다. 또한 일반적인 위상이동법을 적용시킬 경우, 대상체가 진동을 하게 됨으로써 정확한 진동 진폭을 측정하기 어렵다.(중략)

• Journal of Welding and Joining
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• 제3권2호
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• pp.10-15
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• 1985

Roughness of the surface to be welded is one of the important factors affecting the weldabilities on the pressure welding. The purpose of this study is to investigate the influences of the surface roughness upon the welding process and the weldability of pressure welds, using Aluminium AA1050 plates treated by various surface polishing The results obtained are as following. 1. The optimum welding deformation is about 38(%)-42(%) in cold pressure weld. 2. The grinding work on the weld surface is superior to milling and paper polishing. 3. Weld pressure must be beyond $0.5kg/mm^2$ in order that the bond may be achieved.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.821-825
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• 1991

This paper presents an architecture and control logic of a Flexible Manufacturing Cell (FMC) which is one of the important elements under Computer Integrated Manufacturing (CIM) environment. To implement FMC, it is very important to develop a software which can control and monitor the overall system in an integrated environment. Our primary concern in this research is not to develop individual systems, but to integrate them in the hierarchical control level. Progress on the research of integrating CAD/CAM, Process Planning, Off-line Robot Programming and Simulation module into FMC control system is reported. FMC hardware system used here has an Automated Storage & Retrieval System (AS/RS), a conveyor system, a transfer robot, a CNC milling machine, a bar-code system, and an IBM PC/AT as Cell Control System (CCS). In order to demonstrate the operational result, the name plates, text-carved aluminium plates, are manufactured by this system.