• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.3
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• pp.42-47
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• 2011

The partial product matrix (PPM) of a parallel squarer is symmetric. To reduce the depth of PPM, it can be folded, shifted and rearranged. In this paper, we present an area-efficient squarer design method using new partial product rearrangement. Also, a fixed-width squarer design method of the proposed squarer is presented. By simulations, it is shown that the proposed squarers lead to up to 17% reduction in area, 10% reduction in propagation delay and 10% reduction in power consumption compared with previous squarers. By using the proposed fixed-width squarers, the area, propagation delay and power consumption can be further reduced up to 30%, 16% and 28%, respectively.

• Journal of Industrial Technology
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• v.27 no.B
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• pp.229-233
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• 2007

This research investigated the way of generating the flowing of water in case of artificial fluctuation of river width by the unidimensional numerical analysis in order to reconstruct vertical and expanse features of flowing, and the problem of existing numerical analysis in accordance with local enlargement and reduction of river through hydraulic model experiments with results of numerical analysis. The result revealed that when the local section change in the same river is exist, it showed 0.93m in the case of no change of local section in the hydraulic model experiments and numerical analysis, however, it presented 1.645m on the occasion of local section changes in the hydraulic model experiments and numerical analysis. In other words, there was a significant difference in the existing numerical analysis, when there was a local section change. As a result of the experimental section for the enlargement and reduction of local river width, due to the sensitive change for fluctuation of flood discharge, there was a significant difference between numerical analysis and hydraulic model experiments. In addition, the result of comparison between the enlargement and reduction of local river width confirmed that the result of numerical analysis with hydraulic model experiments showed larger generation of deviation in case of enlargement of section than in case of reduction of section.

• Transactions of Materials Processing
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• v.25 no.4
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• pp.235-241
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• 2016

Dimensional accuracy of hot coil is improved by precise control of thickness profiles, flatness, width and winding profile. Especially, precise width control is important because yield could be increased significantly. Precise width control can be improved by predicting the amount of width spread. The purpose of this study is to develop the advanced prediction model for width spread in hot finish rolling for controlling width precisely. FE-simulations were performed to investigate the effect of process variables on width spread such as reduction ratio, forward and backward tension and initial width at each stand. From the statistical analysis of simulated data, advanced model was developed based on the existing models for strip width spread. The experimental hot rolling trials showed that newly developed model provided fairly accurate predictions on the strip width spread during the whole hot finishing rolling process.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.251.1-251.1
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• 2013

Combination of oxidative vacuum annealing and oxygen plasma treatment can serve as a simple and efficient method of line-width modification of imprinted nanopatterns. Since the vacuum annealing and oxygen plasma could lead mass loss of polymeric materials, either one of the process can yield a narrowed patterns. However, the vacuum annealing process usually demands quite high temperatures (${\geq}300^{\circ}C$) and extended annealing time to get appreciable line-width reduction. Although the plasma treatment may be considered as an effective low temperature rapid process for the line-width reduction, it is also suffering for the lowered controllability on application to very fine patterns. We have found that the vacuum annealing temperature can be lowered by introducing the oxygen in the vacuum process and that the combination of oxygen plasma treatment with the vacuum annealing could yield the best result in the line-with reduction of the imprinted polymeric nanopatterns. Well-defined line width reduction by more than 50% was successfully demonstrated at relatively low temperatures. Furthermore, it was verified that this process was applicable to the nanopatterns of different shapes and materials.

• Wind and Structures
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• v.36 no.1
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• pp.41-60
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• 2023

The effect of cladding panel size on the size reduction factor (SRF) of extreme area-averaging wind pressure (EAWP) on the facades of a high-rise building is often ignored in previous studies. Based on wind tunnel tests, this study investigated the horizontal and vertical correlations of wind pressure on the facade claddings of square-section high-rise buildings. Then, the influencing parameters on the SRF of the EAWP on the cladding panels were analyzed, which were the panel area, panel width, panel length and building width. The results show clear regional distinctions in the correlation of wind pressures on the building facades and the rules of the horizontal and vertical correlations are remarkably different, which causes the cladding size ratio to impact the SRF significantly. Therefore, this study suggests the use of the non-dimensional comprehensive size parameter b^𝜶h^1-𝜶/B (𝜶 is the fitting parameter) determined by the cladding panel horizontal size b, cladding panel vertical size h and the building width B rather than the cladding panel area to describe the variation of the EAWP. Finally, some empirical formula for the SRF of the EAWP on the cladding of a high-rise building is proposed with the nondimensional comprehensive size parameter.

• Tribology and Lubricants
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• v.25 no.5
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• pp.311-317
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• 2009

To satisfy the more severe emission regulation and the demand of higher fuel economy in near future, the combustion pressure and power output of engines is going to be higher. In order to get the reduction of engine emission and the higher power, it is needed the reduction of the tension and width of ring pack. The lower tension ring and the thinner width ring can bring not only the friction reduction between the ring and liner during engine running, but also the adjustment of the blow-by gas and oil consumption by changing in the pressure in the crevice volume and the axial motion of rings togethe with the adjustment of the inter-ring crevice volumes. In this study, by using a developed basic computer proglram that predicts the blow-by gas and oil consumption of engines, it is to be examined how satisfying the level of the blow-by gas and oil consumption as being installed the piston ring pack with thinner width ring and lower tension ring.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.1
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• pp.162-167
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• 2013

The most important factor in an aircraft manufacturing is stability and weight reduction. Most of aircraft components are designed with thin plate type to satisfy weight reduction needs. The thin plate is difficult to be machined because it is apt to be vibrated by dynamic force generated in milling process. The most critical factor in machining of aluminum thin plate is width and thickness between stiffeners. So we tested many cases to find out the machinable minimum thickness at different width between stiffeners. And with the data obtained from many tests, this papers suggested the standard width thickness relation that is machinable without vacuum fixture. Machinist will be able to reduce the cost of aircraft thin plate parts by reducing the number of vacuum fixture used by the help of this standard.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.337-340
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• 2006

The purpose of this study is to propose the stiffness reduction factor for flat plate slabs under lateral loads. Current design code (e.g., ACI 318-05) requires considering the effects of cracks for calculating slab stiffness under lateral loads. This study collected the test results of 20 interior slab-column connections, from which stiffness reduction in each test was estimated with respect to the ratio of applied moment to cracking moment ($M_a/M_{cr}$). Based on collected data, this study proposed equations for calculating stiffness reduction with respect to $M_a/M_{cr}$. To verify the proposed equations, this study conducted the experimental test of interior slab-column connections under quasi-static cyclic loading. From the test, load-deformation curve is compared to that obtained from effective beam width method with the proposed equation for the stiffness reduction. It is shown that the effective beam width method with the proposed equation for stiffness reduction predicts accurately the test results.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.125-126
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• 2009

Effective beam width model (EBWM) has been used for analysis of post-tensioned (PT) flat plate slab frames under lateral loads. For analyzing PT flat plate slab structure under lateral loads with good precision, reduction in slab stiffness has to be accurately estimated for Effective beam width model(EBWM). For this purpose, this study collected test results of PT flat plate system conducted by former researches. And this study reduced the width of slab so that the stiffness of the EBWM converged into the lateral stiffness of each test specimens by trial and error. By conducting nonlinear regression analysis, an equation for calculating stiffness reduction factor for the PT flat plate is proposed.

• Transactions of Materials Processing
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• v.14 no.9 s.81
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• pp.791-797
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• 2005

Extensive width reduction of slabs is an important technology for achieving continuous production between the steelmaking and hot rolling processes. However, the vertical horizontal rolling process has many disadvantages, e.g., large width deviations and less efficient width reduction. This study was carried out to investigate the deformation of slab by sizing press with two steps die. To do it, dog-bone and camber are discussed in width sizing process considering the deformation behavior according to the deviation of anvil velocity and the deviation of initial slab temperature. In this paper, the various causes of the sizing press phenomena are mentioned for the purpose of understanding of rolling conditions. As a result, the optimal anvil shape having a minimum-forming load is obtained by FE-simulation and ANN.