• ETRI Journal
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• v.36 no.6
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• pp.942-952
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• 2014

This paper presents a novel test point insertion (TPI) method for a pseudo-random built-in self-test (BIST) to reduce the area overhead. Recently, a new TPI method for BISTs was proposed that tries to use functional flip-flops to drive control test points instead of adding extra dedicated flip-flops for driving control points. The replacement rule used in a previous work has limitations preventing some dedicated flip-flops from being replaced by functional flip-flops. This paper proposes a logic cone analysis-based TPI approach to overcome the limitations. Logic cone analysis is performed to find candidate functional flop-flops for replacing dedicated flip-flops. Experimental results indicate that the proposed method reduces the test point area overhead significantly with minimal loss of testability by replacing the dedicated flip-flops.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1802-1806
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• 2006

It is important to consider the effects of land-use changes on surface runoff, stream flow, and groundwater recharge. Expansion of urban areas significantly impacts the environment in terms of ground water recharge, water pollution, and storm water drainage. Increase of impervious area due to urbanization leads to an increase in surface runoff volume, contributes to downstream flooding and a net loss in groundwater recharge. Assessment of the hydrologic impacts or urban land-use change traditionally includes models that evaluate how land use change alters peak runoff rates, and these results are then used in the design of drainage systems. Such methods however do not address the long-term hydrologic impacts of urban land use change and often do not consider how pollutants that wash off from different land uses affect water quality. L-THIA (Long-Term Hydrologic Impact Assessment) is an analysis tool that provides site-specific estimates of changes in runoff, recharge and non point source pollution resulting from past or proposed land-use changes. It gives long-term average annual runoff for a land use configuration, based on climate data for that area. In this study, the environmental and hydrological impact from the urbanized basin had been examined with GIS L-THIA in Korea.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.4
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• pp.69-76
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• 2002

The aim of this study is to provide fundamental informations that make it possible to use a cool stream and a hot stream simultaneously. We changed the pressure of compressed air that flows into a tube, the inner diameter of orifice that a cold stream exits, and the mass flow rate ratio. And in each case, we measured the temperature of a cold stream and a hot stream in each exit of a tube. Also we measured the axial and the radial temperature distribution in internal spare of a tube. From the study, fellowing conclusive remarks 7an be made. First, As the number of nozzles increase, separation point move into the hot exit. Second, When we use guide vane type nozzle, the axial temperature distribution constant over the 0.75 of air mass flow rate radio. Third, When we use Spiral type nozzle, axial and radial temperature distribution in the inner space is higher than another nozzle. Fourth, Axial and radial temperature distribution in the inner space vortex-tube is determined by separation point. And separation point is moved by changing of air mass flow rate ratio. At last, A heating apparatus is possible far vortex-tube to use.

• Journal of Korean Society on Water Environment
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• v.22 no.4
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• pp.605-613
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• 2006

Discharge characteristics of non-point source pollutant and load amount of the discharge in the urban area were investigated in the Pungyeongjeong-stream basin and the Yongbong-stream basin in this present study. The land use of the studied basins were divided into paddy field, industrial complex area, combined sewage system, separate sewer system and point sources discharge. The descriptive statistics on the event mean concentrations (EMCs) of non-point pollutants by the the land use showed in the range of 4.43-32.28 mg/L for BOD and 8.27~56.17 mg/L for COD. The highest concentration was shown from the combined sewage system. The EMC of SS at the paddy field in the Pungyeongjeong-stream basin showed the highest range with the values ~ from 35.76 to 358.86 mg/L, which might have been influenced by a levee construction in the adjacent of the area. The relatively high concentration values of 4.43~32.28 mg/L and 1.617.13 mg/L emerged from TN and TP,respectively, at the discharge points of the both stream basins.

• Journal of Korean Society of Water and Wastewater
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• v.33 no.5
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• pp.395-404
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• 2019

The point-of-use water dispenser systems are widely used because of convenience in handling and demand for high-quality drinking water. The application has been increased recently in the public places such as department stores, universities and the rest areas in express ways. Improvement of water qualities by the dispenser systems was compared with tap water in this study. The tap water is supplied to the dispenser as the influent of the dispenser system. The twelve dispensers in the public places were used. The five dispensers used reverse osmosis as the main filter and other dispensers used various filters such as ultrafiltration, nanofiltration, and alumina filter. The water quality indicators for sanitation safety, i.e., turbidity and total coliforms, were evaluated. Other water qualities such as pH, residual chlorine, heterotrophic plate count (HPC), and total cell counts were also analyzed. By the point-of-use water dispenser, the turbidity, residual chlorine and pH were decreased and the HPC and total cell counts were increased. The t-test results revealed that the HPC of the tap waters were not significantly different from the treated waters but the total cell counts of the two groups were significantly different. The low pH of the RO filter treatment was also significantly different from the tap waters. This study will contribute to understand the role of the point-of-use water dispenser in improving water quality and to identify key water quality for the proper maintenance of the dispenser systems.

• Korean journal of food and cookery science
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• v.29 no.4
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• pp.331-342
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• 2013

The purposes of this study were to identify the actual utilization condition of combi-steam ovens and to evaluate the importance and the satisfaction of dietitians and cooks who used the oven in school foodservice. A survey of 300 schools, 1 dietitian and 1 cook from each school respectively; total 600, was conducted and 202 completed questionnaires were available for the purpose of the statistical evaluation. The main results of this study were summarized as follows: Among the schools, 70.5% set up the oven during 2007~2009, the most commonly used cooking method was 'Baking (87.0%)' and the way of acquiring recipes for the oven was 'from oven manufacturing company (50.0%)'. The advantage of using the oven was 'the convenient use of the oven (63.3%)' and the disadvantage was 'Difficulty of cooking foods evenly (59.8%)'. The degree of importance and satisfaction on twenty six attributes were measured according to type of school, location of school, number of meal service per day, and number of total serving per day. Among quality attributes of importance of the oven utilization, 19/18 characteristics were assessed over 4 point (important) out of 5 scale by dietitians/cooks respectively and in satisfaction 16/18 were over 4 points (satisfied) by dietitians/cooks respectively. When it comes to the most satisfied factor of combi-steam oven, 'Improvement of cooking baked foods' was highest for dietitians (4.60 point) and 'Checking temperature of cooked foods' was for cooks (4.49 point). In overall satisfaction of the oven use, the average score was 4.10 point for dietitians, 3.98 point for cooks out of a 5 point scale. Using the survey results as a base, school foodservices are required to use the combi-steam oven efficiently to serve high quality of meals for students.

• PNF and Movement
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• v.22 no.2
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• pp.267-274
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• 2024

Purpose: The purpose of this study was to determine the effects of functional insole application using a hallux point on dynamic balance. Methods: Twenty-nine participated in this study. The experiment investigated changes in dynamic balance with the use of a functional insole that emphasized the hallux point. After explaining the experiment to the subjects, the Y-balance test was conducted to measure dynamic balance before the insole was applied. The test was then repeated after the functional insole with the hallux point was. Paired t-tests were used to analyze the statistical differences before and after the application of the functional insole with the hallux point. Results: The functional insole that emphasizes the hallux point significantly increased the distance in the anterior (p<0.05), posteromedial (p<0.05), posterolateral (p<0.05) directions as well as the composite score measured by the Y-balance test compared to before the insole application. Conclusion: The use of a functional insole that emphasizes the hallux point can help the foot pronate during dynamic balance, thereby improving balance through the control of the sole.

• Journal of the Semiconductor & Display Technology
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• v.17 no.2
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• pp.36-40
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• 2018

Point LED applied in Korea is applied to communication RCLED, but it is designed to be suitable for communication, so it does not meet requirements in fiber coupling rate and optical output. - Currently, domestic optical pipe manufacturers use general LEDs for light emitting devices, but Japanese products use high power point LEDs to develop superior point LED (RED 620 ~ 660nm).

• Smart Structures and Systems
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• v.13 no.4
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• pp.547-565
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• 2014

This paper investigates the design of a perfect point load actuator based on flat triangular piezoelectric patches. Applying a difference of electric potential between the electrodes of a triangular patch leads to point loads at the tips and distributed moments along the edges of the electrodes. The previously derived analytical expressions of these forces show that they depend on two factors: the width over height (b/l) ratio of the triangle, and the ratio of the in-plane piezoelectric properties ($e_{31}/e_{32}$) of the active layer of the piezoelectric patch. In this paper, it is shown that by a proper choice of b/l and of the piezoelectric properties, the moments can be cancelled, so that if one side of the triangle is clamped, a perfect point load actuation can be achieved. This requires $e_{31}/e_{32}$ to be negative, which imposes the use of interdigitated electrodes instead of continuous ones. The design of two transducers with interdigitated electrodes for perfect point load actuation on a clamped plate is verified with finite element calculations. The first design is based on a full piezoelectric ceramic patch and shows superior actuation performance than the second design based on a piezocomposite patch with a volume fraction of fibres of 86%. The results show that both designs lead to perfect point load actuation while the use of an isotropic PZT patch with continuous electrodes gives significantly different results.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.5
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• pp.1126-1133
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• 1994

When designing an internal gear. the bending strength around pitch point as well as that at tooth root fillet should be considered because the bending stress around pitch point may occur as high as that at tooth root fillet. In this study, including stress state around pitch point, the bending strength (tensile side and compressive side) of internal gear tooth is investigated by the use of the finite element method(FEM) with regarding many influencing factors of cutter and gear geometries. Then, the critical sections around pitch point and at tooth root fillet are determined, and the simple formulae based on nominal stresses(bending, compressive, and shear) are derived for the calculations of actual stresses as the functions of tooth thicknesses and radii of curvatures of involute and fillet curve at those critical sections. The stresses calculated by the formulae agree well with those by the FEM. And the bending stresses around pitch point and at tooth root are easily estimated by the use of those formulae, therefore, those formulae are useful for the purpose of the design or the bending strength estimation of internal gear.