• Smart Structures and Systems
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• 제14권3호
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• pp.469-477
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• 2014

As a kind of intelligent materials, conductive asphalt concrete has a broad application prospect including melting ice and snow on the pavement, closing cracks in asphalt concrete, sensing pavement damage, and so on. Conductive pavement will be suffered from fatigue failure as conventional pavement in the process of service, and this fatigue damage of internal structure can be induced by electrical signal output. The characteristics of electrical signal variation of conductive asphalt concrete in the process of fatigue cracking were researched in this paper. The whole process was clearly divided into three stages according to resistance changes, and the development of fatigue damage wasn't obvious in stage I and stage II, while in stage III, the synchronicity between the resistance and damage began to appear. Thus, fatigue damage variable D and initial damage value $D_0$ represented by the functions of resistance were introduced in stage III. After calculating the initial damage value $D_0$ under different stress levels, it was concluded that the initial damage value $D_0$ had no noticeable change, just ranged between 0.24 and 0.25. This value represented a critical point which could be used to inform the repair time of early fatigue damage in the conductive asphalt pavement.

• 상하수도학회지
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• 제25권2호
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• pp.223-230
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• 2011

An electrolytic oxidation process was applied to remove odorous compounds from non-point odor sources including wastewater pipelines and manholes. In this study, a distance between the anode and the cathode of the electrolytic process was varied as a system operating parameters, and its effects on odor removal efficiencies and reaction characteristics were investigated. Odor precursors such as sediment organic matters and reduced sulfur/nitrogen compounds were effectively oxidized in the electrolytic process, and a change in oxidation-reduction potential (ORP) indicated that an stringent anaerobic condition shifted to a mild anoxic condition rapidly. At an electrode distance of 1 cm and an applied voltage of 30 V, a system current was maintained at 1 A, and the current density was 23.1 $mA/cm^{2}$. Under the condition, the removal efficiency of hydrogen sulfide in gas phase was found to be 100%, and 93% of ammonium ion was removed from the liquid phase during the 120 minute operating period. Moreover, the sulfate ion (${SO_4}^{2-}$) concentration increased about three times from its initial value due to the active oxidation. As the specific power consumption (i.e., the energy input normalized by the effective volume) increased, the oxidation progressed rapidly, however, the oxidation rate was varied depending on target compounds. Consequently, a threshold power consumption for each odorous compound needs to be experimentally determined for an effective application of the electrolytic oxidation.

• 한국수학교육학회지시리즈A:수학교육
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• 제56권4호
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• pp.387-405
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• 2017

The purpose of this study is to investigate the change of students 'perception and expression about the motion of object following distance function $={x \atop 3}$ and distance function $y=\frac{x^3}{3}+3$ according to the necessity of research on students' perception and expression about integral constant. In this paper, we present the recognition and the expression of the difference of the constant in the relationship between the distance function and the speed function of the students, while examining the process of constructing the speed function and the inverse process of the distance function. This provides implications for the relationship between the derivative and the indefinite integral corresponding to the inverse process. In particular, in a teaching experiment, a constructive activity was performed to analyze the motion of two distance functions, where the student had a difference of the constant term. At this time, the students used the expression 'starting point' for the constants in the distance function, and the motion was interpreted by using the meaning. This can be seen as a unique 'students' mathematics' in the process of analyzing the motion of objects. These scenes, in introducing the notion of the relation between differential and indefinite integral, it is beyond the comprehension of the integral constant as a computational procedure, so that the learner can understand the meaning of the integral constant in relation to the motion of the object. It is expected that it will be a meaningful basic research on the relationship between differential and integral.

• Journal of Chest Surgery
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• 제29권1호
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• pp.1-6
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• 1996

5마리의 잡견(18~22kg)을 이용하여, 경막외강에 생리식염수를 연속 점적하여 뇌사를 유발시킨다. 뇌사발생시 점의 뇌압은 122.0$\pm$6.25mmHg이며 뇌사후 30분 최고치에 도달하였다. 뇌사를 유발시키는데 필요한 생리식염수의 양은 4.8$\pm$1.0ml이었고, 143.0$\pm$30.9분이 필요하였다. 뇌사가 올때까지 동맥압은 변하지 않지만 그후 점차 떨어지고, 맥박수는 뇌사 30분 후 안정시 보다 50% 정도 증가한 최고치에 달한다. 체온, 심박출량, 폐동맥압, 좌심실 이완말기압등의 혈역학적 지표는 뇌사진행 중에는큰 변화가 없었고, 심실 기외수축이 일시적으로 나타난 이외에는 부정맥도 관찰되지 않았다. 급작스러운 뇌압 상승 모델에서 보였던 혈역학적 변화는 관찰되지 않았다.

• 마이크로전자및패키징학회지
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• 제13권1호통권38호
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• pp.1-5
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• 2006

반도체 메모리 소자의 스피드 향상을 위해 저저항 배선층을 채용하는 방안으로 70 nm-두께의 아몰퍼스실리콘과 폴리실리콘 기판부에 $TiSi_2$ 타켓으로 각각 80 nm 두께의 TiSix 복합실리콘을 스퍼터링으로 증착한 후 RTA $800^{\circ}C$-20sec 조건으로 실리사이드화 처리하고 사진식각법으로 선폭 $0.5{\mu}m$의 배선층을 만들었다. 배선층에 대해 다시 각각 $750^{\circ}C-3hr,\;850^{\circ}C-3hr$의 부가적인 안정화 열처리를 실시하였으며, 이때의 면저항의 변화는 four-point probe로 실리사이드층의 미세구조와 수직단면 두께 변화를 주사전자현미경과 투과전자현미경으로 관찰하였다. 아몰퍼스실리콘 기판인 경우 후속열처리에 따른 결정화 진행과 함께 급격한 면저항의 증가가 확인되었고, 이 원인은 결정화 과정에서 실리콘과 복합티타늄실리사이드 층과의 상호확산으로 표면 공공(void)을 형성한 것으로 미세구조 관찰에서 확인되었다. 따라서 복합티타늄실리사이드의 하지층의 종류와 열처리 조건을 바꾸어 저저항 또는 고저항 실리사이드를 조절하여 제작하는 것이 가능하여 복합 $TiSi_2$를 저저항 배선층 재료로 채용할 수 있음을 확인하였다.

• 건축역사연구
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• 제22권2호
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• pp.43-54
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• 2013

Compared to Early Chosun Dynasty, the spatial structure of most local Eupseongs of Korea had a standardized change with the expansion and spread of the Rye-hak(禮學:a study of confucius Rite). Meanwhile in the process of rebuilding Eupseongs there was a tendency of relocation of the local government offices(官衙) and its attached facilities in terms of functions and use. Although it was PyeongSanseong Miryang Eupseong had an unreasonable spatial structure locating Gaeksa(客舍; accommodation house for visitors) in the middle of the local government office complex, and Dongheon(東軒;main office building) in the east of it before the Japanese Invasion of Korea in 1592. However with the reorganization of spatial Structure of local Eupseongs after the Japanese invasion Gaeksa was moved to the foot of Adongsan where commanded a fine view of river. Dongheon was moved to the center of Eupseong for the effective management of its auxiliary organizations. It was because road system and administrative efficiency had a serious effect on deciding the location of the local government office and its attached facilities. After the Japanese invasion Hyangchoeng(鄕廳), having been out of Eupseong, also was moved to the independent location within Eupseong separate from Dongheon and Gaeksa. It seemed to take into account the autonomy of Hyangchoeng. Dongheon, Gaeksa, and Hyangchoeng which are the crucial facilities of Milyang Eupseong were arranged at each angular point of big triangle. In order to enhance the administative efficiency, the attached administrative facilities were arranged surrounding Dongheon and Hyangchoeng. The spatial structure of Milyang Eupseong in the late Choseon dynasty was of great difference from that of uniformly organized system of early Choseon Period. It was because the development of administrative function, the pursuit of efficiency, and commercial progress had a great impact on the change of urban space.

• 건축역사연구
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• 제28권6호
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• pp.19-30
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• 2019

This study explores the application aspect of The detailed rules of Census (1896) through the change of Kan numbers in Gyeonpyeong-bang. Although Gyeonpyeong-bang was a high-priority area because of its location, it was difficult to trace the operation of the urban situation due to lack of data. This study is focusing on restoring space and society in the Gyeonpyeong-bang using the information on the type of houses and the number of Kan listed in the family register of Hanseong-bu. The detailed rules of Census sets out provisions for the family registry and the rules of making Tong. Especially when it comes to the rules of making Tong, this rule deals with the code of making ten Hos into one Tong. This study was conducted by dividing the status of the Tong into three types: uncompleted Tong, exceeded Tong without vacant Ho number, and exceeded Tong with the vacant Ho number. Since these three types of Tong are in the process of change towards the complete Tong with 10 Hos, they were thought to be able to demonstrate the specific application of the rules. This study will be meaningful as a case study that expands the point of existing research on the Tong making rules, which was not focused relatively on restoring urban conditions at that time, by looking at the changes in exceptions that deviated from the Sipgajaktong rule.

• 한국의류학회지
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• 제16권3호
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• pp.233-242
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• 1992

This study primarily concentrates on the Fashion Style of the New Generation which has come into being in 1980 with reference to the contents of the newspaper and magazine in 1950's. . The New Generation has undergone the social and cultural change under the effect of mass communication, mass consumption brought by the economic development, sports boom promoted during the period of Asian Games and Seoul Olympic Games and the adoption of the policy for the autonomous school uniform. In the process of the social and cultural change, they have the common peculiarity such as sensitivity, anthoritarianism and polarity and they have taken an important part in the development of the 'Young Fashion' The characteristics of their fashion styles are divided into three periods as follows; 1. The rising period (1980-1982): The most important pecuriality of the first step can be sum up to the following point. The free fashion style replaced the formal one such as T-shirt or casual wear comes into as a everyday dress. Moreover, many people become interested in the New Fashion which is gradually diversified and high-qualified. As a natural consequence, the lively interest of the people has brought into the appearance and competition of the New Brand in fashion industry 2. The growing period (1983-1986): Mannish Look, so-called 'New Fashion' gained the summit of the fashion and change over conservatively. However, 'Mannish Look' have great effect on the Fashion Style until now on. Specially in Korea, 'Punk Style'and 'Androgynous Look' can be an example among many. 3. The diversifying period (1987-1989): The Fashion Style has developed variously even though the Reactionism takes the lead as the main current of the Korean Fashion. Moreover, it is noticeable that man comes into the stage as a new fashion group and the fashion market begins to dear in various lines of goods with moderate and low prices. These various aspects can be regarded as diversification in the Fashion Style as the needs in the times and society.

• 산업경영시스템학회지
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• 제31권4호
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• pp.121-133
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• 2008

In manufacturing companies, engineering information is a central data which defines a product to be produced. This is changed by various factors such as changes of product configuration, changes of drawings information of a technology's licensor, etc, and these changes essentially accompany the changes of a product BOM (Bill of Materials) structure. Thus, engineering changes gives a heavy burden to information management within enterprise because the changes of product BOM have an influence on each departmental BOM such as a procurement BOM, a manufacturing BOM, a quotation BOM, etc. Especially, these changes of product BOM due to the engineering changes is inevitably and frequently happened by a customer's requirements in a customer-oriented make-to-order manufacturing environments. In these manufacturing environments, information gap among each department from the first contact point of customer to engineering, materials, production, quality, and management is very close, and thus it is very important that the change information of product BOM due to changes of product specification and engineering information are efficiently communicated among each department. This paper describes a procedure of determining product specification and of generating product BOM, and proposes an efficient management scheme for the change process of product BOM information due to changes of product specification and engineering. Also, to show the effectiveness of the proposed product BOM management scheme, a product BOM management system is implemented for the ship engine division of 'H' company, one of customer-oriented make-to-order manufacturing enterprises.

• 분석과학
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• 제34권3호
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• pp.128-133
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• 2021

적정 화학반응에는 화학종의 전위차 변화뿐만 아니라 지시약의 색깔 변화도 포함된다. 전위차 적정에서는 종말점에서 전위의 급격한 변화를 측정하여 적정 곡선을 얻는다. 산-염기 적정은 일반적으로 지시약의 색 변화를 관찰하여 종말점을 결정함으로써 수행된다. 전위차를 측정하여 종말점을 결정하는 방법은 잘 확립 되어 상용화되어 있지만 색의 변화를 관찰하여 종말점을 얻는 장치는 많지 않은 실정이다. 적외선 광원과 감지기로 적정액 방울을 계수하고, 백색광원과 광 검출기로 종말점의 변색을 감지하여 아날로그-디지털 변환기인 아두이노 (Arduino)가 적용된 간단하고 정밀한 스펙트럼 종말점 검출 기구를 제작하였다. Spectrator는 지시약으로 티몰 블루를 사용한 산-염기 적정에서 재현성 측면에서 우수한 결과를 보였다. Spectrator 제작 과정과 이를 사용한 실험결과를 공유한다.