• Fire Science and Engineering
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• v.24 no.5
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• pp.136-141
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• 2010

The purpose of this study is to examine the structure and heat generation mechanism of low voltage switches used to turn on or off the power supply to an indoor lighting system and investigate how the fixtures and movable contacts of the switches are damaged depending on the types of energy sources in order to secure the judgment base for expected PL disputes. Based on the Korean Standard (KS) testing method for incombustibility, this study applied a general flame to the switch. In addition, current was supplied to the switch using the PCITS (Primary Current Injection Test System). The ambient temperature and humidity were maintained at $22{\pm}2^{\circ}C$ and 40~60% respectively while performing the test. It is thought that the switch generated heat due to a defective connection of the wire and clip, insulation deterioration and defective contact of the movable contact, etc. The surface of the switch damaged by the general flame was uniformly carbonized. When the flame source was removed, the fire on the switch was extinguished naturally. From the result obtained by disassembling the switch carbonized by the general flame, it could be seen that fixtures and movable contacts remained in comparatively good shape but the enclosure, clip support, movable contact, indicating lamp, etc. showed carbonization and discoloration. In the case of the switch damaged by overcurrent, the clip connecting the wires, clip support, etc. showed almost no trace of damage, but the fixtures, movable contact, indicating lamp, etc. were severely carbonized. That is, the sections with high contact resistance were intensively damaged and showed a damage pattern indicating that carbonization progressed from the inside to the outside. Therefore, it is possible to judge the initial energy source by analyzing the characteristics of the carbonization pattern and the metal fixtures of damaged switches.

• Progress in Medical Physics
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• v.17 no.2
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• pp.77-82
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• 2006

The image display is an Important component of PACS and of medical digital imaging chain. Displayed image qualify is affected by the physical characteristics of display device, appropriate clinical settings and calibrations, and ambient lighting conditions. The performance of display systems is continuously degraded over time due to luminance deterioration and changes of clinical setting parameters. A routine QC is recommended because the performance of display systems is continuously degraded over time. Ten flat panel monochrome LCD display devices were included in the evaluation of the QC effect. The effect of QC on primary class LCD medical display devices for selected QC tests was evaluated by comparing the performances, luminance response, luminance dependencies, display resolution and display chromaticity in this study, of before and after the calibration procedures. The effects of the QC are significant to luminance response and luminance spatial dependencies test and the other side, are slight to the display resolution and display chromaticity test. A routine QC of display device is essential for the consistency of medical image display and presentation. The study of the QC effects of display devices will play an important role in practical QC procedures of display devices.

• Culinary science and hospitality research
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• v.21 no.1
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• pp.42-57
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• 2015

When a customer chooses a coffee shop, different factors can influence his/her purchase. These factors can include tangible as well as intangible elements such as the coffee shop's atmosphere, layout, and interior. Thus, many coffee brands strive to serve not only a diverse menu, but also a unique quality of environment. This study aimed to investigate the influence of physical environment on customer satisfaction and loyalty in the coffee shop and evaluate the influential power of the physical environment factors using hierarchical regression analysis. Data was collected from customers of coffee shops in Texas, the U.S. The study found that the coffee shops' physical environment influenced the customer's satisfaction and loyalty. Particularly, the coffee shop's physical environment including ambient and interior design greatly influenced the customers' satisfaction. However, a broad range of physical environment factors such as temperature, aroma, lighting, color, and interior furnishings should be provided to increase the customer loyalty. The results may have a broader application to provide effective managerial and marketing information to Korean coffee entrepreneur brand in the U.S. and beyond.

• Culinary science and hospitality research
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• v.19 no.5
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• pp.206-224
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• 2013

The purpose of this study was to examine the formation of customer's repeated use that is real long-term commitment in franchise/chain coffee shops. 457 effective samples were analyzed using PASW 18.0 and AMOS 18.0. The results of the analysis of the relationships between user experience, customer satisfaction, customer commitment and repeated use are as follows. First, it was presented that atmosphere, price fairness and coffee product quality had a positive impact on customer satisfaction. Second, customer satisfaction had a positive impact on customer commitment and repeated use. Finally, there was the mediating effect of continuous commitment between customer satisfaction and repeated use. Based on the results of the above analysis, the managerial implications for increasing repeated use of coffee shops are as follows. First, the strategy for enhancing performance of user experience is to try to improve atmosphere(facilities, ambient/lighting), price fairness, coffee product quality(taste, flavor, temperature). Second, the strategy for forming repeated use is to enhance customer commitment(affective commitment, continuous/normative commitment).

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.17 no.1
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• pp.31-37
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• 2024

In this study, we propose a machine vision-based pedestrian signal detection algorithm that operates efficiently even in computing resource-constrained environments. This algorithm demonstrates high efficiency within limited resources and is designed to minimize the impact of ambient lighting by sequentially applying HSV color space-based image processing, binarization, morphological operations, labeling, and other steps to address issues such as light glare. Particularly, this algorithm is structured in a relatively simple form to ensure smooth operation within embedded system environments, considering the limitations of computing resources. Consequently, it possesses a structure that operates reliably even in environments with low computing resources. Moreover, the proposed pedestrian signal system not only includes pedestrian signal detection capabilities but also incorporates IoT functionality, allowing wireless integration with a web server. This integration enables users to conveniently monitor and control the status of the signal system through the web server. Additionally, successful implementation has been achieved for effectively controlling 50W LED pedestrian signals. This proposed system aims to provide a rapid and efficient pedestrian signal detection and control system within resource-constrained environments, contemplating its potential applicability in real-world road scenarios. Anticipated contributions include fostering the establishment of safer and more intelligent traffic systems.

• Journal of the Korean Applied Science and Technology
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• v.30 no.1
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• pp.127-138
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• 2013

This study investigated the effects of feeding the broilers that are exposed to extreme heat stress (EHS, $33{\pm}2^{\circ}C$) with extreme heat stress diet (EHSD) containing adequate amount of soy oil and other nutrients on their growth performance. 500 broiler chickens (Ross 308) were randomized into five dietary treatment groups according to a randomized block design on the day they were hatched. Each group was further divided into four repeat pens with each repeat pen comprising 25 chickens. The five dietary treatment groups were: T1 (Normal ambient condition + basal diet (BD), T2 (EHS +BCD), T3 (EHS + extreme heat stress diet (EHSD) prepared from BD with tallow replaced with soy oil and containing molasses 2%), T4 (EHS + EHSD prepared from BD with tallow replaced with soy oil and containing molasses 2% and methionine and lysine of 1.5 times greater quantities than in BD), and T5 (EHS + EHSD prepared from BD with tallow replaced with soy oil and containing molasses 2%, methionine and lysine of 1.5 times greater quantities than in BD, and vitamin C 200 ppm) with inverse lighting. The body weight gain of the broilers increased significantly in T4 and T5 as compared with that in T1 and T2. Weights of the lymphoid organ, bursa of Fabricius, thymus, and spleen were similar between all groups. Serum concentrations of IgG, IgG and IgM were higher in T4 and T5 than inT1 and T2, but the corticosterone concentration decreased significantly in them. In T4 and T5, Lactobacillus in the cecum increased, but Escherichia, coliform, and total aerobic bacteria decreased rather significantly, compared with those in T1 and T2. Contents of acetic acid, propionic acid and total SCFA were significantly higher in T4 and T5 than in T1 and T2.

• Journal of Bio-Environment Control
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• v.27 no.3
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• pp.199-205
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• 2018

The aim of this study was to confirm that effects of supplemental LED illumination on a strawberry yield and fruit quality when strawberry grown on a bottom bed to be deficient ambient light due to shading of a upper bed during cultivation by a two-bed bench system. A strawberry was cultivated as a drip irrigation system in the two-bed bench system filled with a strawberry exclusive media from October 2015 to January 2016. The upper and the bottom bed without LED illumination for growth of a strawberry were using as a control. For LED light treatments, from 10 am to 4 pm, we illuminated LEDs as $100{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ of light intensity by using blue, red, and mixing LED (blue plus red) on the strawberry plants of the bottom bed. In the yield of strawberry fruit, the strawberry grown on the bottom bed treated with the blue LED significantly increased compared with that of the bottom bed part control, and increased to by near 90% of the strawberry output of the upper bed part control. The soluble sugar content of strawberry fruit grown on the upper bed part control and on the bottom bed illuminated with blue or mixed LED was higher than that of red LED and the control of the bottom bed. The content of anthocyanin was the highest increased in the strawberry grown on the upper bed part control that received a lot of ambient light, however when comparing only the bottom bed, strawberry fruits grown on all LED treatments were higher than that of the control. Therefore, we considered that using of the blue LED light on the bottom bed of two-bed bench system during strawberry cultivation is advantageous for the increase of yield and improvement of fruit quality.