• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.179-179
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• 2008

$BaTiO_3$를 기본조성으로 하는 PTC 써미스터는 Curie 온도이상에서 저항이 급격히 상승하는 산화물 반도체 세라믹이다. 이러한 성질을 이용하여 degaussing 소자, 정온 발열체, 온도센서, 전류 제한소자 등 상업적으로 여러 분야에서 연구되고 있다. 또한 원가절감 등을 위하여 Ni 내부전극을 사용하여 환원 분위기에서 소결하는 칩 타입에 대한 연구가 진행되고 있다. 본 연구에서는 Sm 함량(0.1at%~1.0at%)을 달리한 $BaTiO_3$(Si, Mn, Ca) 계를 선택하여 3%$H_2/N_2$ 분위기에서 1200~$1260^{\circ}C$, 2h 소결한 후 공기 중에서 재산화 처리하고 재산화 시간에 따른 PTC 특성 변화에 대하여 고찰하였다. 재산화 온도와 시간은 각각 $800^{\circ}C$와 0.5h~10h으로 하였다. Sm 함량을 달리하여 환원 분위기에서 소결한 시편의 미세구조와 PTC 특성과의 상관관계를 관찰한 결과, 소결온도가 낮을수록 PTC 특성은 좋아졌으며, 상온 비저항은 Sm 함량이 높아질수록 낮아졌다. 또한 Sm 함량이 높아질수록 jumping ratio$(R_{max}/R_{25^{\circ}C})$는 낮아졌다. 재산화 시간에 따른 PTC 특성은 다소 떨어졌지만 소결온도에 따라 달리 나타났다. Jumping ratio$(R_{max}/R_{25^{\circ}C})$는 Sm을 0.7 at% 첨가한 계에서 재산화를 1시간 처리한 시편에서 가장 우수하였다.

• Architectural research
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• v.18 no.4
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• pp.179-184
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• 2016

The structure must be periodically checked and measures must be taken to prevent deterioration in building construction. From this point of view, a nondestructive test is essential to estimate whether the construction of buildings is proper, and whether the dimension of depositing concrete is consistent and without damage. This study estimated the thickness of the concrete component of construction framework using the ultrasonic velocity method and the impact echo method, in order to investigate reliability of the estimation of the thickness of normal strength concrete and high strength concrete, leading to the following conclusions. In the estimation of the thickness of the concrete structures, specimens of normal strength of 24MPa and specimens of high strength of 40MPa demonstrated an average error rate of 5.1% and 2.2%, respectively. The impact-echo method, one of the non-destructive tests, is verified as an efficient diagnostic technique. With this information, we will determine specific standards for the maintenance of structures, and the re-creation of lost building blueprints.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.2
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• pp.179-185
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• 2020

DRAM is a major component of the main memory system. As the operating system evolves and application complexity and capacity increases, the capacity and speed of DRAM are also increasing. DRAM should perform a refresh action of periodically reading and then re-storing stored values, and the accompanying performance and power/energy overhead embodies characteristics that worsen as capacity increases. This study proposes an energy efficiency improvement technique that efficiently stores the rows that need to be refreshed within 64ms and 128ms using the bloom filter for cells with the lowest retention time of electrons. The results of the experiment showed that the proposed technique resulted in an average 5.5% performance improvement, 76.4% reduction in average refresh energy, and 10.3% reduction in average EDP.

• Proceedings of the Korean Society of Crop Science Conference
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• 2018.10a
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• pp.179-179
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• 2018

Potato (Solanum tubersosum L.) is susceptible to various environmental stresses such as salt, high temperature, and drought. Especially, potato tuber growth is greatly affected by drought that causes not only yield reduction but also loss of tuber quality. Since unpredictable global weather changes cause more severe and frequent water limiting conditions, improvement of potato drought tolerance can minimize such adverse effects under drought and can impact on sustainable potato production. Genetic engineering can be utilized to improve potato drought tolerance, but such approaches using endogenous potato genes have rarely been applied. We were obtained AtbZIP28 gene transgenic potato plants. It is identified transcript levels at various stress conditions, polyethylene glycol (PEG), NaCl, (ABA). Also, For identification to regulate ER stress response genes in AtbZIP28 gene transgenic potato plant, we screened seven potato genes from RNA-seq analysis under TM treatment. Five and two genes were up- and down-regulated by TM, respectively. Their expression patterns were re-examined at stress agents known to elicit TM, DTT, DMSO and salt stress.

• Journal of Korea Society of Digital Industry and Information Management
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• v.19 no.4
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• pp.179-192
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• 2023

ESG is the hottest topic in recent business management or business administration. In particular, with the release of the IPCC's 6th comprehensive report in 2023, environmental issues have been further raised around the world, and ESG management for sustainable and permanent companies is accelerating by improving social and governance structures, including the environment, and thereby enhancing corporate value. This case study is analyzed based on the theory of sustainable growth, creating shared value, and corporate social responsibility. This study focuses on the case of Samsung Biologics, which is pursuing sustainable growth and management through ESG management. Samsung Biologics is the first Korean company to win the "Terra Carta Seal" award, part of a sustainable market initiative to respond to climate change, and externally, it has acquired the Dow Jones Sustainability Index, acquired the KCGS ESG comprehensive evaluation A grade, acquired the CDP B grade, and acquired the EcoVadis Gold grade. It has joined the Sustainable Market Initiative launched by King Charles III since the World Economic Forum in 2020 to chair the Supply Chain. It has joined RE100, TCFD, and UN Global Compact to lead sustainable management through ESG activities. Therefore, we would like to take a practical approach to ESG management strategies for sustainable growth through the example of this company.

• Journal of Korea Foundry Society
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• v.26 no.4
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• pp.174-179
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• 2006

This study aims to investigate the microstructures and mechanical properties of DCI manufactured by sand and metal mold casting. To prohibit the formation of the chill, carbon, silicon and rare earth($0{\sim}0.2\;wt%$) were controlled and temperature of metal mold was constantly kept at $160^{\circ}C$. The sizes, counts and nodularity ratios of nodules were analyzed by image analysis device. Wear test using pin-on-disc wear tester was carried out under the conditions of load 47.2N, velocity 0.4 m/s and distance 2000 m. Tensile test using Instron type testing machine was performed with velocity of 0.1 mm/min according to the KS B 0802. The formation of the chill was not observed when percentage of the carbon and silicon were 3.8 and 2.5. Mechanical properties of GCD manufactured by metal mold were better than sand casting.

• Journal of the Korean Statistical Society
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• v.35 no.2
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• pp.179-192
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• 2006

In this paper, a new method of modified second order slope rotatable designs (SOSRD) using balanced incomplete block designs (BIBD) for $4{\le}v{\le}16$ is presented. In this method the number of design points required is in some cases less than the number required in Victorbabu (2305) modified slope rotatable central composite designs. Further, a new method of construction of three level modified SOSRD using BIBD is presented. The modified SOSRD can be viewed as SOSRD constructed with the technique of augmentation of second order rotatable design (SORD) using BIBD to SOSRD. These designs are useful in parts to estimate responses and slopes with spherical variance functions.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.11a
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• pp.178-179
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• 2005

Numerical and experimental investigation of incompressible turbulent flow and heat transfer through square channels with varying number of ribbed walls were conducted to determined pressure drop and heat transfer. The CFX solver used for the computation. The rough walls have a $45^0$ inclined square rib. Uniform heat flux is maintained on whole inner heat transfer channel area. The numerical results agreed well with experimental data that obtained for 7600$D_h$) of 0.0667. The results show that values of local heat transfer coefficient and friction factor increase with an increasing number of ribbed walls.

• Journal of Korean Institute of Industrial Engineers
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• v.31 no.2
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• pp.173-179
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• 2005

This paper presents an extended EMQ model which determines an optimal production quantity for a single stage production system when defective items are stochastically produced in the production process and they are re-processed in the rework process to convert them into non-defectives. Through the mathematical modeling, an optimal solution minimizing the average cost per unit time and minimum average cost as well as some properties are derived. It can be shown that each of the existing models is a special case of the proposed model under some conditions. Numerical experiment is carried out to examine the behavior of the proposed model and support properties derived.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.179-182
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• 2000

본 논문은 전화음성 서비스 시스템의 핵심 기술인 멀티채널 음성인식 시스템의 구현에 대해서 기술하고자 한다. 구현한 시스템은 전화망 인터페이스 모듈, 음성입력 모듈, 음성인식 모듈, 및 서비스 제어모듈로 구성되어 있다. 전화망 인터페이스 모듈은 전화망을 이용한 교환기와의 호 처리 및 이벤트 처리를 담당하며, 전화망 접속카드와 밀접한 관계를 가지고 있다. 음성입력 및 인식 모들은 호 접속이 이루어진 채널로부터 음성을 입력받아 단어인식 기능을 수행하는 부분으로서 멀티 채널을 수용할 수 있는 구조로 설계되어 있다. 음성인식 모델은 문맥 종속형 CHMM 모델이며, 각각의 HMM 모델은 3-state, skip path 로 구성되어 있다. 음성인식 모듈내의 함수들은 모두 re-entrant 하도록 구성함으로써 멀티 채별이 가능하며, 각각의 채널은 모두 독립적인 메모리 공간에서 동작하도록 되어있다. 이와 같은 멀티채널 전화음성인식 시스템은 Dialogic보드를 이용하여 Windows NT에서 동작하도록 구현하였다. 실험결과, 구현된 시스템은 실시간으로 상용서비스가 가능한 인식율을 보였으며 원활한 멀티채널 지원이 가능하였다.