• 제목/요약/키워드: CAV system

검색결과 20건 처리시간 0.03초

A VLSI DESIGN OF CD SIGNAL PROCESSOR for High-Speed CD-ROM

  • Kim, Jae-Won;Kim, Jae-Seok;Lee, Jaeshin
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 ITC-CSCC -2
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    • pp.1296-1299
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    • 2002
  • We implemented a CD signal processor operated on a CAV 48-speed CD-ROM drive into a VLSI. The CD signal processor is a mixed mode monolithic IC including servo-processor, data recovery, data-processor, and I-bit DAC. For servo signal processing, we included a DSP core, while, for CAV mode playback, we adopted a PLL with a wide recovery range. Data processor (DP) was designed to meet the yellow book specification.[2]So, the DP block consists of EFM demodulator, C1/C2 ECC block, audio processor and a block transferring data to an ATAPI chip. A modified Euclid's algorithm was used as a key equation solver for the ECC block To achieve the high-speed decoding, the RS decoder is operated by a pipelined method. Audio playability is increased by playing a CD-DA disc at the speed of 12X or 16X. For this, subcode sync and data are processed in the same way as main data processing. The overall performance of IC is verified by measuring a transfer rate from the innermost area of disc to the outermost area. At 48-speed, the operating frequency is 210 ㎒, and this chip is fabricated by 0.35 um STD90 cell library of Samsung Electronics.

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공조설비의 필터차압 변화에 따른 에너지 소비성능 평가 (Evaluation of Energy Consumption of HVAC System for Air Filter Pressure Difference Change in Commercial Buildings)

  • 원근호;곽노열;허정호
    • 설비공학논문집
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    • 제16권12호
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    • pp.1227-1233
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    • 2004
  • Air handling unit (AHU)'s air filter pressure difference is important for energy consumption and indoor air quality. Both energy Performance data and air filter differential pressure of AHU in real office buildings were monitored and analyzed to investigate quantitatively energy impact as dust buildup level on air filter grows. We also modeled and simulated CAV system using HVACSIM+ program to examine the energy effect of dust buildup on filters. Through analysis of time series pressure drop data, the filter pressure difference rate has been increased due to cumulative supply air flow rate increase. As filter pressure drop increased to 1 inch water column, it is found that the supply air flow rate was decreased by 10%, the chilled water flow rate was increased by 5.9% and the pump energy consumption was increased to 5.9%.

이원혼합용액의 초기농도가 동결에 미치는 영향에 관한 실험연구 (EFFECT OF INITIAL SALT CONCENTRATION ON THE FREEZING OF BINARY MIXTURE SATURATED PACKED BED)

  • 최주열
    • Journal of Advanced Marine Engineering and Technology
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    • 제21권5호
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    • pp.527-534
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    • 1997
  • Freezing of an aqueous sodium cWoride solution (Nacl- H20) saturating a packed bed with ini¬tial salt concentrations of 5, 10, 15(k by weight is investigated experimentally in a rectangular cav¬ity. The system was cooled from the top, bottom and a vertical side wall. For the freezing experi¬ments from below, there was little effect of the initial salt concentration throughout the freezing process, and the global freezing rate was not affected by the initial salt concentration. For the freezing from above, the size of the mush region decreased and the mushlliquid interface became flatter as the initial liquid concentration is decreased. For the freezing from vertical side wall, reheating of the mixture was intensified with an increase in the initial salt concentration. For Ci= 5%, supercooling was observed only at the early times of freezing process, but for Ci= 15% small supercooling was observed throughout the freezing process.

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급기각도가 사무실 공간의 냉방 및 난방 성능에 미치는 영향 (The Effect of Supply Angle on Cooling and Heating Performances of Office Space)

  • 김묘선;김영일;정광섭
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2009년도 하계학술발표대회 논문집
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    • pp.497-501
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    • 2009
  • Effect of angle of supply air on cooling and heating performances of office space is studied by numerical simulation. For a constant air volume(CAV) air-conditioning system, air is supplied vertically($90^{\circ}$) and horizontally($10^{\circ}$). Due to buoyancy, the supply angle affects the performance of cooling and heating. In cooling, since the cold supply air tends to move downward due to its high density, horizontal supply angle is better for uniform temperature distribution. In heating, however, vertical supply angle is preferred for better mean and uniform temperature distribution.

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실물실험에 의한 순환공기 바이패스 공조시스템의 성능분석 (The Performance Analysis of a Return Air Bypass Air Conditioning System by a Simulator Experiment)

  • 신현준;김보철;김정엽
    • 에너지공학
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    • 제11권2호
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    • pp.130-135
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    • 2002
  • 바이패스 공조시스템은 냉각코일과 가열코일의 공기통과여부에 따라 크게 외기바이패스, 혼합공기 바이패스와 순환공기 바이패스 공조시스템으로 구분할 수 있다. 이 중에서 순환공기 바이패스 공조시스템은 다른 두 방식과 달리 공조되지 않은 외기가 시스템 내부로 직접 유입되지 않으므로 실내온습도 조절면에서 가장 효율적인 시스템이다. 먼저, 수치계산을 통하여 부하변동에 따른 순환공기 바이패스 공조시스템과 단일덕트 정풍량공조시스템의 실내온습도 구현능력을 비교, 평가하였다. 또한 제안 시스템의 성능분석을 위해 실물실험동을 건립하여 그 실험결과를 수치계산결과와 비교하였다. 실험을 통하여 실현열비가 0.7(현열부하만 변동)인 경우, 실내 최대현열부하에 대한 부분부하시의 실내 현열부하의 비(DSL; Design Sensible Load)가 70% 이내에서는 수치계산, simulator 실험 모두 실내상대습도는 ASHRAE STANDARD 62-1999에서 지정하는 60% 이하로 유지됨을 알 수 있었다. 결론적으로, 바이패스 공조시스템은 실내의 온습도를 정해진 범위의 부하변동내에서는 바이패스 댐퍼의 조작만으로 쾌적한 상태로 유지시킬 수 있으며, 환기회수가 많은 장손의 경우, 순환공기 바이패스에 의해 양질의 실내공기질(IAQ; Indoor Air qualify)을 확보할 수 있다.

국내 아메리칸 핏불테리어에서 발생한 열사병 증례 보고 (Heatstroke occurred in an American Pit Bull Terrier in Korea)

  • 이승희;정지열;정재훈;이현경;박중원;이경기;김종완;소병재;윤순식
    • 한국동물위생학회지
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    • 제41권3호
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    • pp.211-216
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    • 2018
  • Heat stroke in a dog is a life-threatening syndrome characterized by a high body temperature over $41^{\circ}C$, by the central nervous system dysfunction, and by multiple organ dysfunction. A 11-month-old male American Pit Bull Terrier was presented to clarify the cause of death to diagnostic laboratory. This dog showed clinical signs such as high body temperature ($42^{\circ}C$), severe tachypnea, hematochezia, epistaxis and hemoptysis after transportation at hot summer time. At necropsy, there were hemorrhages in skin, serosa of stomach and small intestine, and also dark red fluid in lumen of intestine. Histopathologic examination revealed extensive hemorrhages in stomach, muscle, skin, and tongue. In microbiology, pathologic bacteria such as Pasteurella, Boedetella, Salmonella, Clostridium, and circulating virus in Korea such as CDV, CIV, CAV, CHV, CCV, CPIV were negative except CPV. There were many gross and microscopic lesions suggesting hest stroke while pathologic agents and related lesions were not detected. Therefore we diagnosed this case as heatstroke.

가정간호사업 운용을 위한 정보전달체계 개발 I (가정간호 데이터베이스 구축과 뇌졸중 환자의 가정간호 전산개발) (Development of the Information Delivery System for the Home Nursing Service)

  • 박정호;김매자;홍경자;한경자;박성애;윤순녕;이인숙;조현;방경숙
    • 가정∙방문간호학회지
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    • 제4권
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    • pp.5-22
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    • 1997
  • The purpose of the study was to development an information delivery system for the home nursing service, to demonstrate and to evaluate the efficiency of it. The period of research conduct was from September 1996 to August 31, 1997. At the 1st stage to achieve the purpose, Firstly Assessment tool for the patients with cerebral vascular disease who have the first priority of HNS among the patients with various health problems at home was developed through literature review. Secondly, after identification of patient nursing problem by the home care nurse with the assessment tool, the patient's classification system developed by Park (1988) that was 128 nursing activities under 6 categories was used to identify the home care nurse's activities of the patient with CAV at home. The research team had several workshops with 5 clinical nurse experts to refine it. At last 110 nursing activities under 11 categories for the patients with CVA were derived. At the second stage, algorithms were developed to connect 110 nursing activities with the patient nursing problems identified by assessment tool. The computerizing process of the algorithms is as follows: These algorithms are realized with the computer program by use of the software engineering technique. The development is made by the prototyping method, which is the requirement analysis of the software specifications. The basic features of the usability, compatibility, adaptability and maintainability are taken into consideration. Particular emphasis is given to the efficient construction of the database. To enhance the database efficiency and to establish the structural cohesion, the data field is categorized with the weight of relevance to the particular disease. This approach permits the easy adaptability when numerous diseases are applied in the future. In paralleled with this, the expandability and maintainability is stressed through out the program development, which leads to the modular concept. However since the disease to be applied is increased in number as the project progress and since they are interrelated and coupled each other, the expand ability as well as maintainability should be considered with a big priority. Furthermore, since the system is to be synthesized with other medical systems in the future, these properties are very important. The prototype developed in this project is to be evaluated through the stage of system testing. There are various evaluation metrics such as cohesion, coupling and adaptability so on. But unfortunately, direct measurement of these metrics are very difficult, and accordingly, analytical and quantitative evaluations are almost impossible. Therefore, instead of the analytical evaluation, the experimental evaluation is to be applied through the test run by various users. This system testing will provide the viewpoint analysis of the user's level, and the detail and additional requirement specifications arising from user's real situation will be feedback into the system modeling. Also. the degree of freedom of the input and output will be improved, and the hardware limitation will be investigated. Upon the refining, the prototype system will be used as a design template. and will be used to develop the more extensive system. In detail. the relevant modules will be developed for the various diseases, and the module will be integrated by the macroscopic design process focusing on the inter modularity, generality of the database. and compatibility with other systems. The Home care Evaluation System is comprised of three main modules of : (1) General information on a patient, (2) General health status of a patient, and (3) Cerebrovascular disease patient. The general health status module has five sub modules of physical measurement, vitality, nursing, pharmaceutical description and emotional/cognition ability. The CVA patient module is divided into ten sub modules such as subjective sense, consciousness, memory and language pattern so on. The typical sub modules are described in appendix 3.

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Damage and vibrations of nuclear power plant buildings subjected to aircraft crash part I: Model test

  • Li, Z.R.;Li, Z.C.;Dong, Z.F.;Huang, T.;Lu, Y.G.;Rong, J.L.;Wu, H.
    • Nuclear Engineering and Technology
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    • 제53권9호
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    • pp.3068-3084
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    • 2021
  • Investigations of large commercial aircraft impact effect on nuclear power plant (NPP) buildings have been drawing extensive attentions, particularly after the 9/11 event, and this paper aims to experimentally assess the damage and vibrations of NPP buildings subjected to aircraft crash. In present Part I, two shots of reduce-scaled model test of aircraft impacting on NPP building were carried out. Firstly, the 1:15 aircraft model (weighs 135 kg) and RC NPP model (weighs about 70 t) are designed and prepared. Then, based on the large rocket sled loading test platform, the aircraft models were accelerated to impact perpendicularly on the two sides of NPP model, i.e., containment and auxiliary buildings, with a velocity of about 170 m/s. The strain-time histories of rebars within the impact area and acceleration-time histories of each floor of NPP model are derived from the pre-arranged twenty-one strain gauges and twenty tri-axial accelerometers, and the whole impact processes were recorded by three high-speed cameras. The local penetration and perforation failure modes occurred respectively in the collision scenarios of containment and auxiliary buildings, and some suggestions for the NPP design are given. The maximum acceleration in the 1:15 scaled tests is 1785.73 g, and thus the corresponding maximum resultant acceleration in a prototype impact might be about 119 g, which poses a potential threat to the nuclear equipment. Furthermore, it was found that the nonlinear decrease of vibrations along the height was well reflected by the variations of both the maximum resultant vibrations and Cumulative Absolute Velocity (CAV). The present experimental work on the damage and dynamic responses of NPP structure under aircraft impact is firstly presented, which could provide a benchmark basis for further safety assessments of prototype NPP structure as well as inner systems and components against aircraft crash.

자율주행기반 모빌리티 서비스 도입을 위한 운행설계영역 관점의 도로환경 분석 (A Road Environment Analysis for the Introduction of Connected and Automated Driving-based Mobility Services from an Operational Design Domain Perspective)

  • 우보람;김아름;안용준;탁세현
    • 한국지리정보학회지
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    • 제25권4호
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    • pp.107-118
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    • 2022
  • 최근 자율주행 기술이 상용화 단계로 접어들며, 자율주행기반 모빌리티 서비스를 제공하는 서비스 플랫폼이 늘어나고 있다. 현재 자율주행 기반 모빌리티 서비스들은 자율주행차량의 주행 성능과 기능에 초점을 맞추어 서비스를 제공하고 있으므로 모빌리티 수단별 교통수요와 통행 특성을 고려한 서비스 지역을 선정하는 데에 한계가 있다. 따라서, 본 연구에서는 기존 모빌리티 서비스인 택시와 수요응답형 교통수단, 특별교통수단의 실제 교통 데이터를 활용하여 모빌리티 수단별 통행 특성을 분석하고 자율주행 적용 가능성을 검토한다. 이를 위해 모빌리티 서비스별 주요 사용 네트워크를 도출하고 전문가 조사를 기반으로 네트워크별 자율주행 난이도를 산정하여 모빌리티 서비스별 자율주행 적용 지수를 산출한다. 분석 결과, 수요가 분산된 형태의 모빌리티 서비스보다는 밀집된 형태의 서비스에서 자율주행 서비스 제공이 효율적인 것으로 확인된다. 또한 네트워크에 할당된 통행수요가 높고 자율주행 난도가 낮은 분포가 가장 큰 것은 특별교통수단으로 도출되었다.

규산 및 삼요소 시비수준이 도체내 성분함량과 도열병 발생에 미치는 영향 (The Effects of Silicate Nitrogen, Phosphorus and Potassium Fertilizers on the Chemical Components of Rice Plants and on the Incidence of Blast Disease of Rice Caused by Pyricularia oryzae Cavara)

  • 백수봉
    • 한국응용곤충학회지
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    • 제14권3호
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    • pp.97-109
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    • 1975
  • 수도 도열병의 종합적 방제체계 확립의 일환으로서 합리적인 비료 시용에 의한 효과적 방제 가능성을 알고다 규산, 질소, 인산 및 가리 등 여러 비료를 시용하여 이들이 도체내 성분함량과 도열병 발생에 미치는 영향을 검토하고 나아가 수도품종 및 균주간의 상호관계를 구명하기 위하여 1971년과 1973년에 수도묘에 도열병균을 인공접종 및 자연발병시켜 실험을 실시하였던 바 다음과 같은 결과를 얻었다. 1) 규산을 시용하면 수도 엽신내 규산함량은 크게 증가하고 전당함량과 가리함량도 증가하나 전질소 및 인산함량은 감소되었다. 2) 규산의 시용으로 도체내 C/N 율과 $SiO_2/N$율 및 $K_2O/N$율은 향상되었으며 이들과 도열병 발병지수와는 고도의 부의 상관이 있었다. 3) 규산시용으로 도열병 발병지수는 저하되었다. 4) 도체내 규산함량은 질소질비료를 과용하면 감소되고 전질소함량은 증가되며 전당함량은 감소하여 도열병 저항성을 크게 저하시켰다. 5) 규산함량은 인산질비료를 많이 시용하거나 도체내 인산함량이 증가하면 감소되어 도열병에 대한 저항성을 저하시켰다. 6) 가리질비료를 다시용하면 규산함량은 증가되었고 전질소함량은 감소되었으며 $K_2O/N$율은 증가되는 경향이었다. 그리고 가리함량이 비교적 낮은 상태에서는 도열병에 대한 저항성이 향상되었으나 비교적 높은 수준에서는 도열병에 대한 저항성과 유의적인 상관이 보이지 않았다. 7) 도열병 발병지수는 공시된 균주범위내에서 진흥이 적었고 풍옥이 가장 컸으며 풍광 팔달은 비슷한 정도였다. 도열병균의 병원성은 $P_1,\;P_2,\;and\;P_3$의 순으로 강하였으나 풍옥에 있어서는 일정한 경향을 찾아볼 수 없었다. 엽위별로는 5-6엽기의 묘에서 상위 제2엽이 발병이 많았고 제1엽과 제3엽은 비슷한 정도였다.품종이기 때문인 것 같다. (4) 벼의 수량은 무처리 5,814kg/ha에 비하여 Carbofuran 6,649kg, Cytrolane 6,340kg, BPMC 6,315kg, Chlorphenamidine 6,265kg, Cartap 6,164kg, Diazinon 5,944kg, Diazinon 입제 수면시용 6,102kg로서 Carbofuran 처리구에서 벼의 수량이 가장 높았다. (5) Carbofuran 처리구에서 높은 수량을 보인 것은 Carbofuran 처리구에서 멸구, 매미충류의 밀도가 낮았고 오갈병의 발병율이 낮은데서 온 결과인 것 같다.화안정성은 없었다. 포말성은 87.5$\pm$$2.5\%$였고 용해도는 산성영역 (pH 2와 4)에서 약 83$\~$$84\%$로 높았으나 pH 6이상에서는 44$\~$$50\%$로 낮았다. 보였다.이 한국어와는 다른 것이라거나, 한국어 음성학을 공부하지 않고 한국어를 연구할 수 있다는 뜻은 아닙니다. 의학에도 분야마다 전문의가 있듯이, 언어학도 이제 복잡하고 광범한 학문이 되었으므로 분야별로 전문가가 나오게 된 것뿐입니다. 따라서 "나는 통사론에 관심이 있으므로 소리말에는 관심이 없다"고 말하는 언어학자가 있다면, 이 것은 크게 잘못된 것입니다. 마찬가지로 "나는 소리에만 관심이 있으므로 통사론에는 관심이 없다"고 말하는 음성학자가 있다면, 이 또한 안되는 일입니다. 문의 구성과 어휘 요소와 아무 관련이 없는 말소리의 차이가 무슨 소용이 있으며, 통사 구조를 표현하고 저달하는 말소리를 연구하지 않고 어떻게 통사론을 연구할 수 있겠습니까? 다시 간추리면, 언어는 본질적으로 소리말이고, 언어의 특성과 사용 및 습득도 모두 소리말 형태로 나타납니다. 따라서, 영국의 대학은

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