• Title/Summary/Keyword: Pack Analysis

검색결과 349건 처리시간 0.033초

Development and Charge-Discharge Performance Analysis of Direct Methanol Fuel Cell Power Pack for Mobile Phones (휴대폰용 연료전지 전원공급 시스템 개발 및 충방전 특성 연구)

  • Han, Jae-Sung;Kim, Young-Shol;Park, Eun-Seong
    • Journal of the Korean Electrochemical Society
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    • 제5권1호
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    • pp.27-29
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    • 2002
  • We report a fuel cell power supply unit for mobile phone which operates at room temperature and ambient pressure using liquid methanol and air. The unit consists of a direct methanol fuel cell (DMFC) and a back-up battery connected parallely to the fuel cell. DMFC supplies half of the required power and the back-up battery supplies the other half during talk mode. In standby mode, DMFC covers $100\%$ of the required power and charges the back-up battery as well, Eight unit cells, each having $9 cm^2$ of active area, were connected in series in order to raise the output volotage to $2.5\~3.9V$, which is typical for most mobile phones.

A Study on Cylinder Bore Wear during Engine Durability Test (엔진 내구시험 시 실린더 보아의 마모에 관한 연구)

  • Chun Sang-Myung
    • Tribology and Lubricants
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    • 제22권3호
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    • pp.131-136
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    • 2006
  • Cylinder bore wear may not be a problem in most current automotive engines. However, a small change in cylinder bore diameter can significantly affect the lubrication characteristics and ring axial motion. This in turn can cause to change inter-ring pressure, blow-by and oil consumption in an engine. Therefore, by predicting the wear of piston ring face, ring groove and cylinder bore altogether, the changed ring end gap and the changed volume of gas reservoir can be calculated. Then the excessive oil consumption can be predicted. Being based on the calculation of gas flow amount by the theory of piston ring dynamics and gas flow, and the calculation of oil film thickness and friction force by the analysis of piston ring lubrication, the calculation theory of oil amount through top ring gap into combustion chamber will be set. This is estimated as engine oil consumption. Furthermore, the wear theories of ring, groove and cylinder bore are included. Then the each amount of wear is to be obtained. The changed oil consumption caused by the new end gap and the new volume of oil reservoir around second land, can be calculated at some engine running interval. Meanwhile, the wear amount and oil consumption occurred during engine durability cycle are compared with the calculated values. Next, the calculated amount of oil consumption and wear are compared with the guideline of each pare0s wear and oil consumption. So, the timing of part repair and engine life cycle can be predicted in advance without performing engine durability test. The wear data of cylinder bore diameter are obtained from three engines before and after engine durability test. The calculated wear data of cylinder bore diameter are turn out to be twice of the lower bound of averaged test values at TDC and the lower bound at BDC.

Implementation and Performance Evaluation of Platform Independent Performance Enhanced Software Streaming Technology (플랫폼 독립적 성능 개선 소프트웨어 스트리밍 기술 구현 및 성능평가)

  • O, Chang-Hun;Jeon, Yong-Hee
    • The Journal of Korean Institute of Communications and Information Sciences
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    • 제36권5B호
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    • pp.490-501
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    • 2011
  • Software streaming technology is a service method which can support several application software via streaming in networks. In this paper, we propose a platform independent PESS(performance Enhanced Software Streaming) technology. We design and implement the technology based on Java language. The main features in the implemented system are both platforms to be used in multiple operating systems in addition to Windows system and enhanced performance. In the implemented streaming method, application software is placed on the server and only necessary packs are transmitted in an instant. By virtual file system and clients' virtual registry, if necessary, the users' request is processed by transmitting a very small pack unit. Therefore, server load can be reduced and the streaming speed can also be improved. We present the implementation results and evaluate several performance characteristics of the proposed system.

Functional analysis of expressed sequence tags from the liver and brain of Korean Jindo dogs

  • Kim, Jae-Young;Park, Hye-Sun;Lim, Da-Jeong;Jang, Hong-Chul;Park, Hae-Suk;Lee, Kyung-Tai;Kim, Jong-Seok;Oh, Seok-Il;Kweon, Mu-Sik;Kim, Tae-Hun;Choi, Bong-Hwan
    • BMB Reports
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    • 제44권4호
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    • pp.238-243
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    • 2011
  • We generated 16,993 expressed sequence tags (ESTs) from two libraries containing full-length cDNAs from the brain and liver of the Korean Jindo dog. An additional 365,909 ESTs from other dog breeds were identified from the NCBI dbEST database, and all ESTs were clustered into 28,514 consensus sequences using StackPack. We selected the 7,305 consensus sequences that could be assembled from at least five ESTs and estimated that 12,533 high-quality single nucleotide polymorphisms (SNPs) were present in 97,835 putative SNPs from the 7,305 consensus sequences. We identified 58 Jindo dog-specific SNPs in comparison to other breeds and predicted seven synonymous SNPs and ten non-synonymous SNPs. Using PolyPhen, a program that predicts changes in protein structure and potential effects on protein function caused by amino acid substitutions, three of the non-synonymous SNPs were predicted to result in changes in protein function for proteins expressed by three different genes (TUSC3, ITIH2, and NAT2).

A Study on Ring Face and Groove Wear during Engine Durability Test (엔진 내구시험 시 링 외주면 및 그루브 마모에 관한 연구)

  • Chun Sang-Myung
    • Tribology and Lubricants
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    • 제22권4호
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    • pp.211-217
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    • 2006
  • Ring and groove wear may not be a problem in most current automotive engines. However, a small change in ring face and groove geometry can significantly affect the lubrication characteristics and ring axial motion. This in turn can cause to change inter-ring pressure, blow-by and oil consumption in an engine. Therefore, by predicting the wear of piston ring face, ring groove and cylinder bore altogether, the changed ring end gap and the changed volume of gas reservoir can be calculated. Then the excessive oil consumption can be predicted. Being based on the calculation of gas flow amount by the theory of piston ring dynamics and gas flow, and the calculation of oil film thickness and friction force by the analysis of piston ring lubrication, the calculation theory of oil amount through top ring gap into combustion chamber will be set. This is estimated as engine oil consumption. Furthermore, the wear theories of ring, groove and cylinder bore are included. Then the each amount of wear is to be obtained. The changed oil consumption caused by the new end gap and the new volume of oil reservoir around second land, can be calculated at some engine running interval. Meanwhile, the wear amount and oil consumption occurred during engine durability cycle are compared with the calculated values. Next, the calculated amount of oil consumption and wear are compared with the guideline of each part's wear and oil consumption. So, the timing of part repair and engine life cycle can be predicted in advance without performing engine durability test. The wear data of rings and grooves are obtained from three engines before and after engine durability test. The calculated wear data of each part are turn out to be at the lower bound of aver-aged test values or a little below.

Analysis of Korean Herbal Medicine Used in Case Studies of Treating Urticaria (두드러기 증례 연구에서 사용된 한약 처방 분석)

  • Park, Jung-Gun;Kang, Se-Hyun;Kang, Dong-Won;Kim, Kyu-Seok;Kim, Yoon-Bum
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • 제31권3호
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    • pp.12-25
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    • 2018
  • Objectives : The purpose of this study is to analyze the use of herbal medicine for the treatment of urticaria in case studies and to find the general tendency of herbal medicine treatment and to establish the primary treatment direction of urticaria. Methods : In the domestic databases, Oriental medicine Advanced Searching Integrated System (OASIS), Korean Traditional Knowledge Portal (KTKP), National Discovery for Science Leader (NDSL), Research Information Sharing Service (RISS), we selected among the case study papers published in the last 20 years using search terms related to "urticaria". Reports related to Sasang Constitutional medicine were excluded and total of 15 papers were finally selected. Results : 23 prescriptions were retrieved from 15 papers. The most commonly used prescription was Seungmagalgeun-tang (升麻葛根湯), and Bangpoongtongsung-san (防風通聖散) and Pyeongwi-san (平胃散) were presented twice. Commonly used herbs are Glycyrrhizae Radix et Rhizoma (甘草), Zingiberis Rhizoma Recens (生薑), and Scutellariae Radix (黃芩). 18 out of 78 herbs are belonging to heat-clearing medicinal (淸熱藥) and 16 out of 78 herbs are belonging to exterior-releasing medicinal (解表藥). Concurrent therapies such as acupuncture, pharmacoacupuncture, moxibustion, cupping therapy, ice pack applying therapy were performed and several evaluation methods were used, patient's subjective remission rate was the most used. Conclusions : Through this study, we were able to discover the tendency of herbal medicine prescription for the treatment of urticaria.

Study on Wave Propagation Characteristics Modeling in Tunnel (터널 환경에서의 전파전파 특성 모델링 연구)

  • Jeong, Won-Jeong;Kim, Tae-Hong;Han, Il-Tak;Choi, Moon-Young;Ryu, Joon-Gyu;Lee, Ho-Jin;Pack, Jeong-Ki
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • 제20권9호
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    • pp.1003-1013
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    • 2009
  • In the domestic environments, there are many tunnels since most of terrains have mountains. To ensure the quality of wireless network service in NLOS environment like tunnels which differ from indoor or outdoor wireless channels, researches on wave-propagation characteristics. through such channel are necessary. Especially, in such environment the ground repeater called Gap-Fillers are usually used for satellite mobile services. To make sure that mobile service using satellites in tunnels is available, the research about Gap Filling method is essential. This research is focus on the characterising the wave-propagation through tunnels, to find the appropriate frequency, HPBW of the Gap-Filler antennas, the number of Gap-Fillers, etc. In this paper, we present the effective Gap Filling method in tunnels for ISM band, based on analysis of ray tracing and measurement results.

A prospective randomized trial of xylometazoline drops and epinephrine merocele nasal pack for reducing epistaxis during nasotracheal intubation

  • Patel, Sonam;Hazarika, Amarjyoti;Agrawal, Prachi;Jain, Divya;Panda, Naresh Kumar
    • Journal of Dental Anesthesia and Pain Medicine
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    • 제20권4호
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    • pp.223-231
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    • 2020
  • Background: The most frequent complication of nasotracheal intubation (NTI) is epistaxis. Epinephrine nasal gauze packing has been used conventionally as a pre-treatment for reducing epistaxis, but it carries a disadvantage of pain and anxiety in patients. However, xylometazoline drops are easier to administer and more convenient for patients. We aimed at comparing the effectiveness of xylometazoline drops and epinephrine merocele packing in reducing bleeding and postoperative complications in our population. Methods: Our study enrolled 120 patients in a double-blind randomized controlled trial. We randomly allocated ASA1 or 2 adult patients into 2 groups: Group X and Group E. Group X received 0.1% xylometazoline nasal drops, and epinephrine (1:10,000) merocele nasal packing was used in Group E. The primary outcome was the incidence of bleeding during NTI; the severity of bleeding, navigability, bleeding during extubation, and postoperative complications were secondary outcomes. We used IBM SPSS and Minitab software for statistical analysis, and P < 0.05 was considered statistically significant. Results: We analyzed the data of 110 patients: 55 in Group X and 55 in Group E. The two groups did not have different bleeding incidence (56.4% vs 60.0%; P = 0.70); however, the incidence of severe bleeding was less with xylometazoline than with epinephrine (3.63% vs 14.54%; P < 0.05). We also observed less bleeding during extubation (38.2% vs 68.5%; P < 0.05) with xylometazoline. Other secondary outcomes were akin to both groups. Conclusion: The incidence of severe and post-extubation bleeding was significantly less with xylometazoline. Hence, it may be an effective alternative for reducing the incidence and severity of epistaxis during NTI.

A Study on the Architectural Change of Traditional Farmhouse in Hyounpong Province (현풍군 근대 농가(農家)의 건축적 변용에 관한 연구)

  • Choi, Ji-Ae;Beak, Young-Hum;Pack, Young-Hea
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 한국주거학회 2008년 추계학술발표대회 논문집
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    • pp.425-430
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    • 2008
  • Residential architecture was a lot more changed due to adopting modern residential type since 1960s. But people in farm houses are still living in a space of their past life causing a discrepancy. For this reason, the paper will identify the changed use for farm houses focusing on their plane views, and reason for the changed use as well. The result of this paper is expected to play a role for practical data to reasonably change and re-model farm houses located in back of cities such as Hyunpoong area. Targeted area for this paper, in order to survey change in residential environment due to industrialization and modernization, has narrowed down to 42 farm houses which are located Yuga-Myun, Hyunpoong-Gun, Dalsung-Gun where tradition and modern characteristics are harmonized being built before 1960s Researching relied on both documentary records and survey on the site, and survey on documentary records was performed in a way that preceding research for changed use of residential area was to be compared with people's farm houses in Kyeongsang-Do area, and survey on the site was carried out by photographing and land surveying and interview and analysis for them, and finally we acquired the result by analyzing use of interior for houses and plane view and relations between culture and social environment. From the result of this paper, there was a trend that farm houses had been improved function of a specific space by enlarging space and enlarged construction for inner rooms. And among spaces, kitchen and bath room was mostly enlarged its left side, and inner room had mostly enlarged its rear side, and kitchen was frequently enlarged in its side space. These kinds of variation in space is believed to be result of change of life style and house facilities

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ViP: A Practical Approach to Platform-based System Modeling Methodology

  • Um, Jun-Hyung;Hong, Sung-Pack;Kim, Young-Taek;Chung, Eui-Young;Choi, Kyu-Myung;Kong, Jeong-Taek;Eo, Soo-Kwan
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제5권2호
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    • pp.89-101
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    • 2005
  • Research on highly abstracted system modeling and simulation has received a great deal of attention as of the concept of platform based design is becoming ubiquitous. From a practical design point of view, such modeling and simulation must consider the following: (i) fast simulation speed and cycle accuracy, (ii) early availability for early stage software development, (iii) inter-operability with external tools for software development, and (iv) reusability of the models. Unfortunately, however, all of the previous works only partially addresses the requirements, due to the inherent conflicts among the requirements. The objective of this study is to develop a new system design methodology to effectively address the requirements mentioned above. We propose a new transaction-level system modeling methodology, called ViP (Virtual Platform). We propose a two-step approach in the ViP method. In phase 1, we create a ViP for early stage software development (before RTL freeze). The ViP created in this step provides high speed simulation, lower cycle accuracy with only minor modeling effort.(satisfying (ii)). In phase 2, we refine the ViP to increase the cycle accuracy for system performance analysis and software optimization (satisfying (i)). We also propose a systematic ViP modeling flow and unified interface scheme based on utilities developed for maximizing reusability and productivity (satisfying (ii) and (iv)) and finally, we demonstrate VChannel, a generic scheme to provide a connection between the ViP and the host-resident application software (satisfying (iii)). ViP had been applied to several System-on-a-chip (SoC) designs including mobile applications, enabling engineers to improve performance while reducing the software development time by 30% compared to traditional methods.