• Journal of Energy Engineering
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• v.22 no.2
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• pp.105-111
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• 2013

The present study has been carried out to reduce the heat loss from a built in refrigerator by using reverse heat loss method to discern the region with larger heat loss. To perform this purpose, an infrared thermographic camera has been used to measure the surface temperature of the refrigerator and tried to improve the heat loss near the ice dispenser. The numerical heat transfer analysis also has been accomplished to clarify the heat transfer mechanism near the ice dispenser. The possible applicable method to reduce heat loss was increasing the curvature radius at the ice dispenser corner. The curvature radius has been changed from 0mm to 40mm to see the effect of the curvature at the corner. From the present research, the optimal curvature radius for the reduction of heat loss at the ice dispenser could be 30mm.

• Ecology and Resilient Infrastructure
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• v.7 no.4
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• pp.320-326
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• 2020

The present study aimed to assess the longitudinal connectivity owing to migrant characteristics of the target fish. The study area was Wonju-cheon Stream, and the target species were Zacco platypus and Minnows. The HEC-RAS model was used for the computation of the flow, and the ICE (Information sur la Continuite Ecologique) method was used to analyze the longitudinal connectivity. The longitudinal connectivity was assessed using the minimum overflow height, velocity, and depth of the cross sectional structure of a plunge pool and considering the swimming speed of the target fish. Simulation results indicated that the longitudinal connectivity scores for the Zacco platypus and Minnows were approximately 76 and 23, respectively.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.3
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• pp.367-376
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• 2009

In this clinical research, the fluoride tape(SCMC-T-5) using fluoride(NaF) was developed and manufactured and the treatment effect of the fluoride tape in dentin hypersensitivity patients was evaluated and compared with the effect of existing fluoride varnish($CavityShield^{TM}$). Twenty two healthy adult patients(88 teeth) having dentin hypersensitivity participated in this clinical research and they were divided into two groups. The fluoride product was applied according to the manufacturer's instruction and the level of pain in the tooth after giving irritation using compressed air and ice stick was measured just after the application, after 3 days, after a week and after 4 weeks each using visual analog scale(VAS). In the experimental group, compared with the early VAS scores, all other VAS scores showed the significant decreases statistically. In the control group, all VAS scores except the VAS score of 34.091(air) measured 3 days after(using the irritation examination by the compressed air) showed the significant decreases statistically when compared with the early VAS scores. The fluoride tape and fluoride varnish used in this clinical research were able to treat the dentin hypersensitivity effectively.

• Journal of Platform Technology
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• v.9 no.4
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• pp.90-96
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• 2021

Most of the vehicles currently under development and in operation are equipped with various IoT sensors, but some of the factors that cause car accidents are relatively difficult to detect. One of the major risk factors among these factors is black ice. Black ice is one of the factors most likely to cause major accidents, as it can affect all vehicles passing through areas covered with black ice. Therefore, black ice detection technique is essential to prevent major accidents. For this purpose, some studies have been carried out in the past, but unrealistic factors have been reflected in some parts, so research to supplement this is needed. In this paper, we tried to detect black ice by analyzing color images using the CNN technique, and we succeeded in detecting black ice to a certain level. However, there were differences from previous studies, and the reason was analyzed.

• Korean Journal of Remote Sensing
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• v.40 no.3
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• pp.285-293
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• 2024

This study explores the use of Sentinel-1 Synthetic Aperture Radar (SAR), processed through Google Earth Engine (GEE), to monitor changes in the areas of Antarctic ice shelves. Focusing on the Campbell Glacier Tongue (CGT) and Drygalski Ice Tongue (DIT),the research utilizes GEE's cloud computing capabilities to handle and analyze large datasets. The study employs Otsu's method for image binarization to distinguish ice shelves from the ocean and mitigates detection errors by averaging monthly images and extracting main regions. Results indicate that the CGT area decreased by approximately 26% from January 2016 to January 2024, primarily due to calving events,while DIT showed a slight increase overall,with notable reduction in recent years. Validation against Sentinel-2 optical images demonstrates high accuracy,underscoring the effectiveness of SAR and GEE for continuous, long-term monitoring of Antarctic ice shelves.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.11b
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• pp.937-940
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• 2002

인터넷의 확산과 더불어 전자 우편의 사용이 크게 늘면서 스팸메일의 심각성이 대두되고 있다. 현재 스팸메일을 막기 위한 여러 가지 기법이 제안되고 있으나, 대부분의 방법이 메일 서버내의 정책에 따른 메일 필터링으로, 스팸메일로 인해 네트워크 자원이 소실되는 문제는 여전히 해결되지 않고 있다. 또한 여러 메일 서버가 같은 내용의 메일로 반복적으로 공격을 당하게 된다. 본 논문에서는 게이트웨이 수준에서의 메일감시를 통하여 불필요한 스팸메일로부터 네트워크 자원을 보호하고, 내부 메일 서버 전체를 보호 할 수 있는 시스템에 대해 논의 해보고자 한다. 커널 레벨에서의 패킷 감시로 속도가 빠르고, 또한 가상의 커넥션을 맺어 게이트웨이에서 메일을 완전히 받은 후 검사하므로 더욱더 다양한 정책으로 SMTP를 감시할 수 있으며, 이 시스템은 IP 기반의 다른 프로토콜이나 타 서비스로의 응용 또한 기대할 수 있다.

• Journal of Ocean Engineering and Technology
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• v.11 no.3
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• pp.144-152
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• 1997

본 논문에서는 1년생 빙맥에 의하여 해양구조물에 작용하는 하중을 추정할 수 있는 모델을 제시하였다. 1년생 빙맥을 수면하부(keel), 수면상부(sail), 경화층(consolidated layer)의 3부분으로 나누어 각 부분에 의한 하중을 추정할 수 있는 방법을 논의하였다. 수면하부는 얼음조각(ice rubble)이 층으로 쌓여져 형성된 것이므로 수면하부에 의한 하중추정을 할 때 얼음조각을 선형 Mohr-Coulomb재료로 생각하여 토질역학(soil mechanics)의 이론을 사용하였다. 수면상부에 의한 하중도 토질역학 이론을 이용하여 추정하였으며 경화층에 의한 하중은 Korzhavin식을 이용하여 추정하였다. 제시한 모델을 이용하여 빙맥하중 추정에 미치는 인자들의 영향을 검토하였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.10a
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• pp.608-611
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• 2022

The existing navigation applications mainly have a function that informs speed control, and it does not warn the location of black ice. If the navigation application performs this function, it will have a great effect on reducing traffic accidents. Therefore, in this paper, we propose a method for detecting black ice and a navigation application that warns it.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.249-255
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• 2006

The optimum culture conditions for the ice nucleating activity and the cell growth of Xanthomonas translucens KCTC 2751 were investigated. The optimum initial pH and temperature for the cell growth and the ice nucleating activity were 6.5 and $25^{\circ}C$, respectively. The optimum culture medium for the ice nucleating activity was composed of 1.0% maltose, 1.4% yeast extract, 0.8% digested of gelatin, and 0.03% KCI in distilled water. Freezing operations carried out on distilled water showed that the degrees of supercooling were $-7.90^{\circ}C$ without ice nucleators, $-1.56^{\circ}C$ with silver iodide as a commercial ice nucleator, and $-1.36^{\circ}C$ when Xanthomonas translucens KCTC 2751 were added. During progressive freeze-concentration assays, the addition of Xanthomonas translucens KCTC 2751 led to lower saccharose concentrations in the crystals, while the cells led to higher saccharose concetrations in the concentrated phase.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.558-564
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• 2021

The water purifier market has increased rapidly in recent years. The welding technology of the evaporator is a key component that determines the level of ice production and the cold water performance of an ice purifier. The finger type evaporator of an ice purifier can remove ice and is divided largely into an instant heat method and a hot gas method. In the hot gas type evaporator, particularly during the production process, the pinhole phenomenon inside the copper pipe and clogging problems occur intermittently when welding high-pressure pipes due to the high-temperature oxygen welding. Its use in a water purifier can cause a problem in that ice and cold water do not form, and repairs cannot be made on site. To solve this problem, in this study, a cap jig was applied to improve the welding defect of the hot gas evaporator. In addition, the oxygen welding flame size was adjusted so that the heat source could be well supplied to the cap jig, and the effectiveness was confirmed through a wave pressure test, a test, and a thermal shock test.