• Title/Summary/Keyword: 실용재

Search Result 154, Processing Time 0.029 seconds

MTCMOS ASIC Design Methodology for High Performance Low Power Mobile Computing Applications (고성능 저전력 모바일 컴퓨팅 제품을 위한 MTCMOS ASIC 설계 방식)

  • Kim Kyosun;Won Hyo-Sig
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.42 no.2 s.332
    • /
    • pp.31-40
    • /
    • 2005
  • The Multi-Threshold CMOS (MTCMOS) technology provides a solution to the high performance and low power design requirements of mobile computing applications. In this paper, we (i) motivate the post-mask-tooling performance enhancement technique combined with the MTCMOS leakage current suppression technology, and (ii) develop a practical MTCMOS ASIC design methodology which fine-tunes and integrates best-in-class techniques and commercially available tools to fix the new design issues related to the MTCMOS technology. Towards validating the proposed techniques, a Personal Digital Assistant (PDA) processor has been implemented using the methodology, and a 0.18um Process. The fabricated PDA processor operates at 333MHz which has been improved about $23\%$ at no additional cost of redesign and masks, and consumes about 2uW of standby mode leakage power which could have been three orders of magnitude larger if the MTCMOS technology was not applied.

Introduction of evidence-based practical medicine through safety classification for herbal medicine(1) (한약의 안전성 등급화를 통한 근거중심실용의학적 연구(1) - Aristolochic acid 함유 한약재를 중심으로 -)

  • Park, Yeong-Chul;Lee, Sundong
    • The Journal of Korean Medicine
    • /
    • v.35 no.1
    • /
    • pp.114-123
    • /
    • 2014
  • Objectives: Evidence-based medicine(EBM) advocates the use of up-to-date "best" scientific evidence from health care research as the basis for making medical decisions. EBM also has been applied to traditional Korean medicine(TKM), especially in the field of safety. Recently, the standard prescription for TKM by Korea Institute of Oriental Medicine was published based on toxic index from various toxicity tests. However, there are some limitations when the results from the study based on EBM are applied in clinics. To overcome these imitations, the term "evidence-based practical medicine" was developed and defined as clinically applicable results from the study based on EBM. And safety classification for TKM was suggested as an example of evidence-based practical medicine. Methods: For safety classification for TKM, the data for $LD_{50}$(50% lethal dose), which was transformed to theoretical $LD_1$(1% lethal dose), was analyzed as one of tools for EMB study and divided by maximum dose used in clinics. Results and Conclusions: As a result, human equivalent dose(HED)-based MOS(margin of safety) for korean traditional medicine was calculated and used for safety classification with 5 categories. These categories would be helpful for oriental medicine clinicians to decide the increase and decrease of dosage according to various factors such as patient's sensitivity, potential toxicity of herbal medicines, clinician's experience for better cure. Thus, this safety classification provides some evidences enough that evidence-based practical medicine should be not the same with EBM and defined differently from EBM.

Analysis of Confinement Effectiveness for FRP Confined Concrete Columns (FRP로 구속된 콘크리트 압축부재의 구속효과 분석)

  • Choi, Eunsoo;Choi, Seung-Hwan
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.31 no.1A
    • /
    • pp.19-24
    • /
    • 2011
  • Concrete columns strengthening effect due to FRP (Fiber Reinforced Polymer) confinement depends on the elastic modulus of the FRP. This study analyzes the retrofitting effect of FRP confinements according to elastic modulus of FRPs using the existing data and suggests a practical model to assess the strengthening effect. This study subdivides the FRP elastic modulus into three parts based on normal concrete and steel elastic modulus. The slope and the y-axis intersection seem to increase with increasing FRP elastic modulus. In addition, the strengthening effect does not develop up to some amount of FRP confinement having relatively smaller elastic modulus than the compressive elastic modulus of concrete. In this case, a linear model to assess the strengthening effect is hard to be used. Thus, this study suggests that the FRP jackets having 2 times larger elastic modulus than that of concrete are recommended to be used for retrofit of concrete and that a linear model can be applied for the case. The suggested model shows nearly the same result regardless to the restraint of the y-axis intersection. This has been observed at the model of steel confinement and, thus, is a reliable result.

Study on Anisotropy of Normally Consolidated Clay Soils (정규압밀점성토의 이방성에 관한 연구)

  • 권오순;정충기
    • Geotechnical Engineering
    • /
    • v.11 no.1
    • /
    • pp.41-50
    • /
    • 1995
  • In situ clay soils with Ko condition have anisotropic characteristics, varying the response according to the principal stress direction upon loading. But because of their practicality and simplicity, consolidated isotropic undrained compression tests are commonly used in practice to determine the behavior of cohesive soils. In this study to investigate the anisotropic characteristics and the effects of consolidation stress states on the response of normally consolidated clay soils during shearing, triaxial compression and extension tests after consolidating the undisturbed clay soil samples, which are obtained as a block sample to normalized consolidation states under isotropic or Ko state, were carried out. As a result of tests, the anisotropy of the undrained strength was confirmed. Comparing the soil responses between isotropic and Ko consolidation, the undrained strength by isotropic consolidation is overestimated because of its higher mean consolidation pressure. And isotropic consolidation reduces the anisotropy of soil response and influences on the stress-strain behavior and pore pressure response because the animotropic soil structure is partially collapsed during isotropic consolidation process. Also, OCR in overconsolidated soils is decreased by isotropic consolidatiorL Friction angle in eztension is higher than that in compression, but regression analysis shows that friction angle with cohesion in extension is almost the same as that without cohesion in compresslon.

  • PDF

Cardiac MRI (심장 자기공명영상)

  • Lee, Jong-Min
    • Investigative Magnetic Resonance Imaging
    • /
    • v.11 no.1
    • /
    • pp.1-9
    • /
    • 2007
  • The obstacles for cardiac imaging are motion artifacts due to cardiac motion, respiration, and blood flow, and low signal due to small tissue volume of heart. To overcome these obstacles, fast imaging technique with ECG gating is utilized. Cardiac exam using MRI comprises of morphology, ventricular function, myocardial perfusion, metabolism, and coronary artery morphology. During cardiac morphology evaluation, double and triple inversion recovery techniques are used to depict myocardial fluidity and soft tissue structure such as fat tissue, respectively. By checking the first-pass enhancement of myocardium using contrast-enhanced fast gradient echo technique, myocardial blood flow can be evaluated. In addition, delayed imaging in 10 - 15 minutes can inform myocardial destruction such as chronic myocardial infarction. Ventricular function including regional and global wall motion can be checked by fast gradient echo cine imaging in quantitative way. MRI is acknowledged to be practical for integrated cardiac evaluation technique except coronary angiography. Especially delay imaging is the greatest merit of MRI in myocardial viability evaluation.

  • PDF

Effect of $Cr_2O_3$ and $Nb_2O_5$ Additives on the Microstructure and Piezoelectric Properties of PZT Ceramics for Piezoelectric Composite Sensor (압전복합센서용 PZT 세라믹스의 미세구조 및 압전특성에 미치는 $Cr_2O_3$$Nb_2O_5$ 첨가효과)

  • Paik, Jong-Hoo;Eom, Heyung-Keun;Lim, Eun-Kyeong;Kim, Chang-Il;Lee, Mi-Jae;Choi, Byung-Hyun;Kim, Sei-Ki
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2005.11a
    • /
    • pp.27-28
    • /
    • 2005
  • 본 연구에서는$Cr_2O_3$$Nb_2O_5$ 를 첨가한 $Pb(Zr_{0.54}Ti_{0.48})O_3$ 세라믹스에서 $Nb_2O_5$ 첨가량에 따른 소결 및 압전, 유전특성을 조사하였다. $Pb(Zr_{0.54}Ti_{0.48})O_3$ + 0.2 wt% $Cr_2O_3$ + wt% $Nb_2O_5$ ($0.{\sim}2wt.%$)의 첨가량에 따른 압전, 유전특성 및 미세구조에 관해 연구하였다. 본조성에서 $Nb_2O_5$ 첨가량이 증가함에 따라 입경의 크기는 증가하였으며, 0.5 wt% $Nb_2O_5$ 첨가조성에서 $4\sim5\mu m$의 최대 평균입경을 보이다가 그 이상의 첨가 조성에서 급격히 감소하였다. 유전상수와 kp 는 $Nb_2O_5$ 첨가량이 1.0 wt% 조성까지 증가하였다가 그 이상 조성에서 감소하였다. $Nb_2O_5$ 첨가량이 증가함에 따라 삼방정(rhombohedral)구조에서 정방정(tetragonal)구조로 상전이 일어났으며, 본 조성의 상경계 영역인 0.5 wt% 조성에서 $\varepsilon_r$ = 730, $k_p$ = 0.72, $d_{33}$ = 450, $g_{33}$ = 70의 우수한 압전 특성을 나타내었다. 이러한 조성은 접촉센서용 복합압전소재의 실용가능성을 제시하였다.

  • PDF

Reverse-Engineering and Analysis of Performance for Medium-Altitude Long Endurance Unmanned Aerial Vehicle (중고도-장기체공 무인비행을 위한 비행체 성능 분석 및 역설계)

  • Shim, Ho-Joon;Chang, Kyoungsik;Chung, In Jae;Kim, Sun-Tae;Joh, Chang-Yeol
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.44 no.6
    • /
    • pp.520-529
    • /
    • 2016
  • The main purpose of this study was to analyze the performance of a medium-altitude long endurance unmanned aerial vehicle through reverse-engineering method. The external configuration data of the RQ-1 Predator was reverse-engineered from related photos and specification data available on public domains, which also were used to generate the CATIA modeling and weigh distribution data of the UAV. The aerodynamic characteristics of RQ-1 Predator were mainly predicted the vortex lattice method and an empirical method, which the propeller performance was analyzed by the empirical method proposed by Howe. The rate of climb, service ceiling, range, and the loiter endurance of the UAV was analyzed, which showed good agreement with the reference data.

A Design Method for Dynamic Selection of SOA Services (SOA 서비스의 동적 선택 설계 기법)

  • Bae, Jeong-Seop;La, Hyun-Jung;Kim, Soo-Dong
    • Journal of KIISE:Software and Applications
    • /
    • v.35 no.2
    • /
    • pp.91-104
    • /
    • 2008
  • Service-Oriented Computing (SOC) is the development method that published services are selected and composed at runtime to deliver the expected functionality to service clients. SOC should get maximum benefits not only supporting business agility but also reducing the development time. Services are selected and composed at runtime to improve the benefits. However, current programming language, SOC platforms, business process modeling language, and tools support either manual selection or static binding of published services. There is a limitation on reconfiguring and redeploying the business process to deliver the expected services to each client. Therefore, dynamic selection is needed for composing appropriate services to service clients in a quick and flexible manner. In this paper, we propose Dynamic Selection Handler (DSH) on ESB. we present a design method of Dynamic Selection Handler which consists of four components; Invocation Listener, Service Selector, Service Binder and Interface Transformer. We apply appropriate design patterns for each component to maximize reusability of components. Finally, we describe a case study that shows the feasibility of DSH on ESB.

Developing Practical Recycling methods of FRP Boats (FRP선박의 실용적 재활용 방법 연구)

  • Yoon, Koo-Young
    • Journal of the Korean Society for Marine Environment & Energy
    • /
    • v.10 no.3
    • /
    • pp.167-172
    • /
    • 2007
  • Since 1990s, these many researchers have been fully involved in developing recycling methods for FRP boats. There are four basic classes of recycling covered in the literature. the first is "Mechanical recycling" which involves shredding and grinding of the scrap FRP in a new product. Despite of the safety hazards, mechanical recycling is one of the simpler and more technically proven methods. Recent researchers should be more interested in these methods. It is fact that most of FRP wastes are depended on incineration or reclamation. Because it Is made up of reinforced fiber glass, it is very difficult to break into pieces. By the disposing of waste FRP this way, it also occurs secondary problem such as air pollution and unacceptable noise. This study is to propose a new method which is efficient and environment friendly waste FRP regenerating.

  • PDF

Single use Automatic Lancet to Minimize Pain During Skin Puncture (피부관통시 통증을 최소화하는 일회용 자동 모세혈액 채취기구)

  • 김현식;김경아;전명희;김태임;정용현;이태수;차은종
    • Journal of Biomedical Engineering Research
    • /
    • v.23 no.4
    • /
    • pp.323-327
    • /
    • 2002
  • Chronic diabetic patients need to sample capillary blood for monitoring and controlling the blood sugar level. Frequent sampling requires to minimize pain during skin puncture. The present study developed mechanisms to minimize pain with effective sampling procedure. which consisted of tapered spring, guiding tunnel, and 30G needle Penetration depth was limited to within 2mm for pain reduction as well as for safety. Simple no-reuse mechanism also prevented the cross-patient and secondary infection possibility. Clinical experiments demonstrated the best convenience and safety with minimal pain in the diabetes, normal, and nursing students groups. Sing1e blood sampling was enough for successful blood sugar test by portable analyzer. The present sing1e use auto-lancet should be of great convenience in frequent capillary blood sampling for the diabetes.