• Title/Summary/Keyword: pcm

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Pattern Classification of Multi-Spectral Satellite Images based on Fusion of Fuzzy Algorithms (퍼지 알고리즘의 융합에 의한 다중분광 영상의 패턴분류)

  • Jeon, Young-Joon;Kim, Jin-Il
    • Journal of KIISE:Software and Applications
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    • v.32 no.7
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    • pp.674-682
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    • 2005
  • This paper proposes classification of multi-spectral satellite image based on fusion of fuzzy G-K (Gustafson-Kessel) algorithm and PCM algorithm. The suggested algorithm establishes the initial cluster centers by selecting training data from each category, and then executes the fuzzy G-K algorithm. PCM algorithm perform using classification result of the fuzzy G-K algorithm. The classification categories are allocated to the corresponding category when the results of classification by fuzzy G-K algorithm and PCM algorithm belong to the same category. If the classification result of two algorithms belongs to the different category, the pixels are allocated by Bayesian maximum likelihood algorithm. Bayesian maximum likelihood algorithm uses the data from the interior of the average intracluster distance. The information of the pixels within the average intracluster distance has a positive normal distribution. It improves classification result by giving a positive effect in Bayesian maximum likelihood algorithm. The proposed method is applied to IKONOS and Landsat TM remote sensing satellite image for the test. As a result, the overall accuracy showed a better outcome than individual Fuzzy G-K algorithm and PCM algorithm or the conventional maximum likelihood classification algorithm.

Real-time PCM Data Processing System Development for Flight Test Control (비행시험통제용 실시간 PCM 자료처리시스템 개발)

  • Park, In Hee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.25 no.6
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    • pp.825-833
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    • 2021
  • In flight tests, aircraft moves in real time, so it is important that data from instrumentation/measurement equipment used to determine aircraft status are processed in necessary form and transmitted to flight control systems in real time. Therefore, through telemetry data processing time reduction and processing cycle improvement in flight test control computer data processing system, in order to provide faster slave-data and safety judgment information to radar/telemetry slave-data processing, flight safety analysis system, emergency destruction transmission system, etc., we developed a PCM processing system that can be operated independently by installing data processing software that can receive and process PCM data in current telemetry data processing system and radar information at the same time. In this paper, we explain classified software functions in detail, starting with overall structure of PCM data processing systems developed by supplementing existing systems. Additionally, PCM data processing system will be supplemented through system stabilization and test operation.

A Working-set Sensitive Page Replacement Policy for PCM-based Swap Systems

  • Park, Yunjoo;Bahn, Hyokyung
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.17 no.1
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    • pp.7-14
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    • 2017
  • Due to the recent advances in Phage-Change Memory (PCM) technologies, a new memory hierarchy of computer systems with PCM is expected to appear. In this paper, we present a new page replacement policy that adopts PCM as a high speed swap device. As PCM has limited write endurance, our goal is to minimize the amount of data written to PCM. To do so, we defer the eviction of dirty pages in proportion to their dirtiness. However, excessive preservation of dirty pages in memory may deteriorate the page fault rate, especially when the memory capacity is not enough to accommodate full working-set pages. Thus, our policy monitors the current working-set size of the system, and controls the deferring level of dirty pages not to degrade the system performances. Simulation experiments show that the proposed policy reduces the write traffic to PCM by 160% without performance degradations.

An experimental study on thermal performance evaluation of PCM mixed coating material constructed in and out of the wall (벽체 내·외부에 시공한 PCM혼입 도료의 열적성능 평가에 관한 실험적 연구)

  • Ju, Dong-Uk;Shin, Sang-Heon;Lee, Han-Seung
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2014.05a
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    • pp.216-217
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    • 2014
  • Optimum finishing position, thickness and phase change temperature of winter and summer season were selected and suitability of finishing materials was evaluated based on temperature measurement of specimens applying the coating material mixed phase change materials(PCM). As a result, when finishing position was interior and finishing thickness of coating material mixed n-Octadecane(28℃ PCM) was 4mm, thermal performance was effective. n-Octadecane in summer season and n-Hexadecane(18℃ PCM) in winter season are indicated effective on energy savings, respectively.

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Location-Aware Hybrid SLC/MLC Management for Compressed Phase-Change Memory Systems (압축 기반 상변화 메모리 시스템에서 저장 위치를 고려한 하이브리드 SLC/MLC 관리 기법)

  • Park, Jaehyun;Lee, Hyung Gyu
    • IEMEK Journal of Embedded Systems and Applications
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    • v.11 no.2
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    • pp.107-116
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    • 2016
  • Density of Phase-Change Memory (PCM) devices has been doubled through the employment of multi-level cell (MLC) technology. However, this doubled-capacity comes in the expense of severe performance degradation, as compared to the conventional single-level cell (SLC) PCM. This negative effect on the performance of the MLC PCM detracts from the potential benefits of the MLC PCM. This paper introduces an efficient way of minimizing the performance degradation while maximizing the capacity benefits of the MLC PCM. To this end, we propose a location-aware hybrid management of SLC and MLC in compressed PCM main memory systems. Our trace-driven simulations using real application workloads demonstrate that the proposed technique enhances the performance and energy consumption by 45.1% and 46.5%, respectively, on the average, over the conventional technique that only uses a MLC PCM.

An Experimental Study on the Thermal Performance of Cement Mortar with Granulated PCM

  • Jeong, You-Gun;Park, Ki-Bong;Lee, Han-Seung
    • Journal of the Korea Institute of Building Construction
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    • v.12 no.5
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    • pp.548-557
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    • 2012
  • In this study the thermal performance of G-PCM replaced for find aggregate in mortar specimens was evaluated using TG-DTA. As a result, it was found that when solid changed into liquid, it absorbed heat, and when liquid changed into solid, it radiated heat. In addition, the fluidity and the compressive strength of mortar with G-PCM can be applied to the floor mortar and a wall finish material. Also the higher the replacement ratio, the larger the latent heat capacity. It was found that the mortar with G-PCM slowed the increase and decrease of temperature. Thus, the duration of pleasant indoor temperature is extended by the floor and wall mortar with G-PCM. In conclusion, G-PCM is expected to reduce the heating energy consumption.

Thermodynamic performance of 2-PCM latent heat thermal energy storage system (2-PCM 잠열축열 시스템의 열역학적 성능)

  • 이세균;우정선;이재효;김한덕
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.12 no.2
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    • pp.189-199
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    • 2000
  • This paper investigates the thermodynamic performance of latent heat thermal energy storage system using two phase change materials(2-PCM system). The thermodynamic merit of using 2-PCM is clear in terms of exergetic efficiency, which is substantially higher than that of 1-PCM system. Optimum phase change temperature to maximize the exergetic efficiency exists for each case. The heat transfer area ratio of high temperature storage unit, X, becomes another important parameter for 2-PCM system if the phase change temperatures of given materials are different from those of optimum conditions. It is a good approximation for X$_{opt}$ to be 0.5 when optimum phase change temperatures are used. Otherwise X$_{opt}$ is determined differently as a function of given phase change temperatures.res.

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COMPARISON OF THREE PCM PERFORMANCE EVALUATION SYSTEMS IN TAIWAN

  • Wen-der Yu ;Yen-ping Hsu
    • International conference on construction engineering and project management
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    • 2005.10a
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    • pp.719-724
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    • 2005
  • It has been debating on the performance evaluation of professional construction management (PCM) services since its introduction to Taiwan's construction industry more than a decade ago. Several evaluation systems were proposed by previous researchers. However, there has no comparison study been conducted for the feasibility, effectiveness, and appropriateness of these systems to the performance management (PM) of practical PCM services. This paper is intended for this end to compare the existing PCM performance evaluation systems in Taiwan. A real world design/build (D/B) building project was selected for case study. The result of case study concludes and compares the pro's and con's of the three systems. At the end, it recommends strategies for selecting the most appropriate PCM performance evaluation for PCM services.

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Development of Thermoregulating Textile Materials with Microencapsulated Phase Change Materials (I) -Preparation and Characterization of Microcapsules by Coacervation- (PCM 마이크로캡슐을 이용한 열조절 섬유소재 개발 (I) - 코아세르베이션법을 이용한 마이크로캡슐의 제조 및 특성분석 -)

  • 신윤숙;손경희;조은경
    • Proceedings of the Korean Fiber Society Conference
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    • 2001.10a
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    • pp.397-400
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    • 2001
  • 상변화물질(phase change material, PCM)은 외부온도변화에 따른 상변화에 따라 흡열과 방열성을 반복적으로 나타내는 물질로서 건축, 우주항공분야 등에서 열전달매체나 열조절시스템에 응용되어 왔다. 이러한 PCM의 응용방법은 PCM을 미세한 입자(직경이 약 100$\mu\textrm{m}$)로 만들어 직접 운반유체 속에 분산시켜 이용하거나, PCM을 심물질로 하는 마이크로캡슐을 제조하여 이용하는 방법을 들 수 있다. (중략)

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Thermal Characteristics of the Garment Air-layers by PCM Concentration Changes (상변화물질 농도변화에 따른 의복내 공기층의 열적 특성)

  • Yoo, Hwa-Sook;Lim, Ji-Hye;Kim, Eun-Ae
    • Journal of the Korean Society of Clothing and Textiles
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    • v.32 no.6
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    • pp.991-998
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    • 2008
  • This study is to determine the effects of PCM concentration on the temperature changes of the air layers of a garment when the environmental temperature changes. The selected PCM was Nonadecane and coated on cotton fabrics with PCM concentrations 10%, 20%, and 30%. The temperature changes of the air layers between fabrics were measured by Human-Clothing-Environment Simulator which measure a dynamic heat transfer. After stabilizing at $34^{\circ}C$ for 1 hour, the multi layered garment system were exposed to $5^{\circ}C$ or $10^{\circ}C$ for 30 minutes and then, exposed to $34^{\circ}C$ for 30minutes. The results like following could be obtained. When the environmental temperature changed high to low, temperature of the air layer increased by heating effect of PCM. In the contrast, when the environmental temperature changed low to high, the temperature increase of the air layer was delayed because of cooling effect by PCM. Also, the more concentration of PCM, the bigger the heating effect. Cooling effect showed more clearly at PCM concentration 20%. The temperature differences of the air layers between with PCM fabrics and with non-PCM fabrics were bigger at $10^{\circ}C$ than at $5^{\circ}C$. Consequently, though PCM has influenced on the temperature of the air layer by heating and cooling effect, those effects haven't shown in all layers equally. It was shown that the effect of PCM varied according to the layer in the case of multi layered garment system and heat gain as well as heat loss in the outermost layer had to be taken into account.