• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.943-946
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• 2011

The electronic absorption and surface morphology evolution of two types of molecular double layer thin films, copper phthalocyanine (CuPc) layer deposited on chloro[subphthalocyaninato]boron(III) (SubPc) layer, denoted as SubPc/CuPc, and vice versa, with various thicknesses were investigated using ultraviolet (UV)-visible spectroscopy and atomic force microscopy (AFM). Both types of double layer structures showed similar broadened absorption patterns in the UV-visible region that were consistent with the fitted spectra following simple linear combination of the single layer absorption spectra of the two materials. In contrast, the surface morphology of double layer structures was dependent on the order of deposition. For the CuPc/SubPc structures, surface morphology was characterized by elongated grains, which are characteristic of SubPc thin films, indicating that the morphological influence of the underlying CuPc layer on the subsequent SubPc layer was not large. For the SubPc/CuPc structures, however, the underlying SubPc layer acted as a morphological template for the subsequently deposited CuPc layer. It was also observed that the grain size of the CuPc layer varied according to the thickness of the underlying SubPc layer.

• Polymer(Korea)
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• v.34 no.3
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• pp.237-241
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• 2010

Mechanical characteristics and chemical resistance have been investigated for PC/PBT blends. The changes in mechanical performance of PC/PBT blends was monitored during the treatment with both the PC thinner and general-purpose thinner to figure out the chemical resistance. The PC thinner greatly affected the mechanical properties of PC/PBT blends compared with general-purpose thinner. In the case of PC thinner treatment, the mechanical performance was improved with increased PC content at lower PC content ranges, say below 50%. However the mechanical performance was dropped rapidly at higher PC content ranges due to poor chemical resistance of PC. Transparent pure PC specimen became opaque after chemical treatment with PC thinner, and this can be interpreted by solvent-induced crystallization.

• Journal of the Korean Chemical Society
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• v.39 no.3
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• pp.176-185
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• 1995

To improve photosensisitizing efficiency of ZnO/$H_2Pc(I)_x$ system, ZnO/$H_2Pc(I)_x$ system was dispersed in a typical photoconductive polymer of poly(9-vinylcarbazole)(PVCZ). The iodine dopant level(x) of ZnO/${\chi}-H_2Pc(I)_x$ is proportional to concentration of iodine, whereas x of ZnO/${\beta}-H_2Pc(I)_x$ decreased from the highest x=0.97 at more than $6.3{\times}10^{-3}$ M iodine solution. The Raman spectra of ZnO/${\chi}-H_2Pc(I)_x$ at 514 nm exhibited characteristic $I_3^-$ patterns in the range of 50∼550 $cm^{-1}$ at $x{\geq}0.57.$ The surface photovoltage of ZnO/${\chi}-H_2Pc(I)_{0.48}$/PVCZ was approximately 1.6 times greater than ZnO/${\chi}-H_2 Pc(I)_{0.48}$ and was 1.8 times of ZnO/${\chi}-H_2Pc(I)_{0.57}$/PVCZ at 670 nm. With ZnO/$H_2Pc(I)_x$/PVCZ, the highest iodine dopant levels showed a higher photovoltage. Therefore the injection of holes from H2Pc into PVCZ resulted in that photosensisitizing effect of ZnO/$H_2Pc(I)_x$/PVCZ system was improved compared to ZnO/$H_2Pc(I)_x$ case.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.2 s.54
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• pp.199-205
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• 2009

Recently, as the concern for the development of a construction method for an environmental protection and for tall building is increasing, the use of the half precast concrete(PC) slab that has the solution of environmental problems and the advantage such as reduction of construction period is being demanded. However, there is shortcoming that the crack can occur easily while constructing, and these cracks can have a bad influence upon the structural performance of PC composite slab. However, there is little studies on the influence of these cracks on the structural performance of composite PC slab. In this study, the specimen caused the crack before pouring topping concrete in the half PC slab and the PC composite slab without the cracks were produced to investigate the structural performance of PC composite slab with crack.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.5
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• pp.415-425
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• 2000

An open architecture manufacturing strategy intends to integrate manufacturing components on a single platform so that a particular component can be easily added and/or replaced. Therefore, the control scheme based upon the open architecture concept is hardware-independent. In this paper, a modular and object oriented approach for a PC-based open robot control system is investigated. A standard reference model for robot systems, which consists of three modules; hardware module, operating system module, and application software module, is first proposed. Then, a PC-based Open Robot Controller(PC-ORC), which can reconfigure robot control systems in various production environments, is developed. The PC-ORC is built upon the object-oriented method, and allows an easy implementation and modification of various modules. The PC-ORC consists of basic softwares, application objects, and additional hardware device on the PC Platform. The application objects are: sequencer, computation unit, servo control, ancillary equipment, external sensor control, and so on. In order to demonstrate the applicability of the PC-ORC, the proposed PC-ORC configuration is applied to an industrial SCARA robot system.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10c
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• pp.346-348
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• 2003

본 논문에서는 TCP/IP프로토콜을 사용하는 LAN환경에서 PC들을 사용한 PC클러스터에 관해 연구하였다. LAN환경의 PC들은 안정된 사용환경을 확보할 수 있고, 특정한 사용 시간에 따라 작업을 배치할 수 있는 특징을 갖는다. 또한 별도의 전용의 클러스터를 설치하기 위한 하드웨어가 필요로 하지 않는 장점도 갖는다. 특히 PC실험 실습실의 PC들은 주로 주간 시간대(오전9시~오후6시)에만 실험실습 수업에 사용이 되고, 야간 시간대(오후6시~익일 오전9시)에는 사용되지 않는 유휴 시간을 갖는다. 이러한 사용되지 않는 유휴 시간대의 PC들을 CPU지향적인 복잡한 작업들을 연산하기 위해 사용할 수 있으며, 별도의 클러스터 시스템을 구성하기 위한 하드웨어(클러스터를 위한 컴퓨터들, 스위치장비, 케이블링 등)를 구입할 필요가 없기 때문에 저가격의 고성능을 요구하는 PC클러스터를 쉽게 구성할 수 있다. 공동실험실습실의 PC들마다 유휴기간을 Time table에 예약하고 이에 따라 작업을 배치하고 연산결과를 수집한다. 장기간의 연산작업이 필요로 하는 대규모 연산에 사용함으로써 상당한 경제적 효과를 얻을 수 있다. 또한 동일 실습실의 PC들은 대개 동일한 성능의 동일한 하드웨어와 운영체제를 사용하는 PC들로 구성되기 때문에 Homogeneous node로 구성된 PC 클러스터를 구축하기가 용이하다.

• Journal of the KSME
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• v.30 no.S1
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• pp.67-73
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• 1990

1980년대 초에 등장하기 시작한 위크스테이션이 최근에 PC 시장을 누르고 서서히 부상하기 시작 하였고 몇 년 안에는 기존의 PC시장을 점유하리라 예측은 어렵지 않게 되었다. 왜냐하면 위크스 테이션은 기존 PC에 비해 고해상 그래픽스, 고성능 프로세서, 복잡한 공학용 계산능력, 대형 디 스프레이, 특수입력장치, 메모리 증대 그리고 무엇보다도 공학적 응용에서 표준이라 할 수 있는 UNIX O/S를 기본으로 하는 등의 많은 장점을 갖고 있기 때문이다. 그럼에도 불구하고 PC가 당분간, 아마도 금세기 말까지는, 특히 위크스테이션의 가격이 PC와 경쟁력을 가질 때까지는, 그 위세를 유지할 것으로 예상된다. 그 이유는 PC가 출현한 이후 지난 10년간 PC를 위한 주변장 치와 S/W 개발에 참여한 업체가 무수히 많아 위크스테이션에 비해 PC 이용자의 선택의 폭이 아직도 훨씬 넓다는 이외에 UNIX와 DOS O/S를 모두 채택한 368PC의 등장으로 어느 정도 기존 PC의 단점이 보완되고 있기 때문이다. 앞으로 위크스테이션이 자료 수집 및 처리과정에 까지도 기존 PC를 압도한다 하더라도 결국은 위크스테이션도 개인용 컴퓨터이고 보면 이는 PC의 새 로운 변신으로 보아야겠다.

• Polymer(Korea)
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• v.25 no.6
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• pp.811-817
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• 2001

Crystallization behaviour of bisphenol A polycarbonate(PC) from amorphous phase was studied by varing solvent/nonsolvent ratios in liquid phase. Chloroform and isopropanol were used as a solvent and a nonsolvent, respectively. Samples were characterized by optical microphotography, scanning electron microscope (SEM), X-ray diffaction (XRD), and differential scanning calorimeter (DSC). DSC and XRD measurement were used to determine the crystallinity of PC. The solubility constant seems to critical to control the PC crystallinity in solvent/nonsolvent mixture. The difference in PC crystallinity is explained by the difference in solubility constant of the mixture depending on the solvent/nonsolvent ratio. PC solution of 75/25 wt% (solvent/nonsolvent) ratio produced PC powder showing maximum crystallinity. At this condition solubility constant (9.85) of the mixed solvent was close to PC (9.9).

• Journal of the Korean housing association
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• v.17 no.5
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• pp.55-65
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• 2006

The objective of this study is to provide new direction on house design in consideration of the PC users' life pattern. This study found that PC use present conditions at home, demand for PC using space, and requirements for PC using area were analyzed. A survey was taken by 1108 residences, and the SPSS win.10 was applied for analysis. The survey was conducted to see the computer usage at home, demand and satisfaction for the PC using space. The results of this study were as follows; forty-seven percent of respondents said they used the PC in son's and daughter's room while 36.8% answered living room. It reflects that the whole family want to use the PC in the same area, or for their children's convenience. Users' consciousness was analyzed four factor, which were 'physical inconvenience:'satisfactions in PC position', 'inconvenience caused by narrowness', 'notion of privacy'. PC users' consciousness had significant differences in the satisfaction by PC users' characteristic and housing characteristic. It was to be classified that the PC use space into several pattern according to furniture arrangement, and channel pattern had the highest satisfaction among those pattern. Through this study, it is expected that new housing designs need to be made to reflect lese requirements into interior design and house plan for PC user's needs.

• Korean Journal of Construction Engineering and Management
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• v.22 no.2
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• pp.53-62
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• 2021

PC component allocation and loading plan can contribute to reductions in carbon dioxide emission and energy use of vehicles and total project costs with increased utilization of vehicle loading space. The study derived 18 considerations that PC construction plant managers and site managers take into account when they plan allocation and loading of PC components. Then, IPA (Importance and Performance Analysis) was performed to assess importance and performance of the 18 considerations. Results show that in the PC component allocation planning, considerations regarding the number of vehicles and existence of yard for storing PC components have not been taken into account well by the managers. In the PC component loading planning, PC component loading direction has not been reflected well by the managers although it is considered important by them. Recently, ill-planning issues of PC component transportation, such as inefficient use of vehicle space and loading with low stability, are frequent due to various types of PC components produced. In this context, if the results of this study are reflected in the development of component allocation and loading planning, vehicle management of PC projects would be more efficient, thereby leading to economic project management.