• 제목/요약/키워드: Negative Stability

검색결과 812건 처리시간 0.027초

Impact Analysis of NBTI/PBTI on SRAM VMIN and Design Techniques for Improved SRAM VMIN

  • Kim, Tony Tae-Hyoung;Kong, Zhi Hui
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제13권2호
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    • pp.87-97
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    • 2013
  • Negative bias temperature instability (NBTI) and positive bias temperature instability (PBTI) are critical circuit reliability issues in highly scaled CMOS technologies. In this paper, we analyze the impacts of NBTI and PBTI on SRAM $V_{MIN}$, and present a design solution for mitigating the impact of NBTI and PBTI on SRAM $V_{MIN}$. Two different types of SRAM $V_{MIN}$ (SNM-limited $V_{MIN}$ and time-limited $V_{MIN}$) are explained. Simulation results show that SNM-limited $V_{MIN}$ is more sensitive to NBTI while time-limited $V_{MIN}$ is more prone to suffer from PBTI effect. The proposed NBTI/PBTI-aware control of wordline pulse width and woldline voltage improves cell stability, and mitigates the $V_{MIN}$ degradation induced by NBTI/PBTI.

Foreign Uncertainty and Housing Distribution Market in Korea

  • Jeon, Ji-Hong
    • 유통과학연구
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    • 제16권12호
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    • pp.5-11
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    • 2018
  • Purpose - We investigate the relationship between economic policy uncertainty (EPU) of the US and China and housing distribution economy in Korea using EPU indexes of two countries and the economic indicators in Korea. Research design, data, and methodology - We use the data such as the Korean housing price stability index (HPSI), housing purchase price index (HPPI), housing lease price index (HLPI), banking stock index (BSI), and consumer price index (CPI) with EPU indexes from January 1999 to December 2017. As an empirical methodology, we select the vector error correction model (VECM) due to the existence of cointegration. Result - As results of the impulse response function, the impact of the US EPU index has initially a negative response on the Korean HPSI, HPPI, and HLPI referring the housing distribution market including the economic variables, BSI, and CPI. Likewise, the impact of index in China has initially a negative response on economic indicators except the BSI in Korea. Conclusions - This study shows that the EPU index of the US has significantly negative relationships on all economic indicators in Korea. In this study, we reveal EPU of the US and China has dynamic impact on housing distribution economy returns in Korea.

Stabilizing Control of DC/DC Buck Converters with Constant Power Loads in Continuous Conduction and Discontinuous Conduction Modes Using Digital Power Alignment Technique

  • Khaligh Alireza;Emadi Ali
    • Journal of Electrical Engineering and Technology
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    • 제1권1호
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    • pp.63-72
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    • 2006
  • The purpose of this raper is to address the negative impedance instability in DC/DC converters. We present the negative impedance instability of PWM DC/DC converters loaded by constant power loads (CPLs). An approach to design digital controllers for DC/DC converters Is presented. The proposed method, called Power Alignment control technique, is applied to DC/DC step-down choppers operating in continuous conduction or discontinuous conduction modes with CPLs. This approach uses two predefined state variables instead of conventional pulse width modulation (PWM) to regulate the output voltage. A comparator compares actual output voltage with the reference and then switches between the appropriate states. It needs few logic gates and comparators to be implemented thus, making it extremely simple and easy to develop using a low-cost application specific integrated circuit (ASIC) for converters with CPLs. Furthermore, stability of the proposed controllers using the small signal analysis as well as the second theorem of Lyapunov is verified. Finally, simulation and analytical results are presented to describe and verify the proposed technique.

Effects of CSR Activities on Business Performance of Logistics Firms

  • JEON, Ho-Jin;KIM, Young-Min;YOUN, Myoung-Kil
    • 유통과학연구
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    • 제17권12호
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    • pp.23-32
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    • 2019
  • Purpose As consumer awareness grows, the importance of CSR becomes even more important for long-term growth. In response to this current trend, the purpose of this study is to analyze the effect of CSR activities on business performance for logistics companies. Research design, data, and methodology - Between CSR activities and growth, there was a generally positive(+) relationships between activities such as donation and volunteerism and the growth of the enterprise. In terms of the relationship between environmental factors and growth, negative results were expressed. In case of profitability, improved welfare for workers has had a positive impact on corporate profitability. Results - With respect to stability, a high proportion of equity capital is not considered to be more active in SCR activities. Significant negative results were given between the minimum factors for entry, transportation, and noise generation factors and the ratio of liabilities, which are representative friction factors in the community. Conclusions - With respect to stability, a high proportion of equity capital is not considered to be more active in SCR activities. Significant negative results were given between the minimum factors for entry, transportation, and noise generation factors and the ratio of liabilities, which are representative friction factors in the community.

도시주부의 결혼 만족도와 離婚태도에 관한 연구 (A Study on Urban wives' Marital satisfaction and Divorce Attitude)

  • 박찬미;서병숙
    • 가정과삶의질연구
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    • 제5권2호
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    • pp.145-162
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    • 1987
  • The purpose of this study is to investigate the relations between Wives' marital satisfaction and Divorce attitude as a basis building in marital stability . A measurement tools used for this study are marital satisfaction scale, which was adapted and reproducted from Dyadic Adjustment Scale(DAS) developed by Spanier and Divorce attitude Scale, which was developed by researcher refer to preceding study connected with a cause of divorce. The subjects were 354 married women dwelling in Seoul. Statistical methods such as frequency, percentile. mean , standard deviation, one way ANOVA, and Pearson Correlation were used for data analysis. The results of this study are as follows; 1) there is the tendency to high marital satisfaction group rather more than low marital satisfaction group and to permissional attitude group rather more than negative attitude group about divorce attitude. 2) There was difference in marital satisfaction by number of children, wives's educational level, parents marriage happiness. While, there was no difference in marital satisfaction by length of marriage, family income, wives employments status, marriage pattern. 3) There was partially difference in wives' attitude toward divorce by wives educational level, family income. Both there was no difference in wives attitude toward divorce by the other factors. 4) wives' attitude toward divorce correlates with marital satisfaction. The correlation coefficients is 283 significantly of .001 level. The more satisfaction wife feels about her own matrimony. the more negative a attitude she has toward divorce. This menas that attitude toward divorce depends upon their matrimony. 5) The four type of marital stability are as follows; high marital stability type, high subjective unstability type, high objective unstability type, high marital unstability type.

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Numerical Study of Unsaturated Infinite Slope Stability regarding Suction Stress under Rainfall-induced Infiltration Conditions

  • Song, Young-Suk;Hwang, Woong-Ki
    • 지질공학
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    • 제24권1호
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    • pp.1-8
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    • 2014
  • Numerical stability analysis of an unsaturated infinite slope under rainfall-induced infiltration conditions was performed using generalized effective stress to unify both saturated and unsaturated conditions The soil-water characteristic curve (SWCC) of sand with a relative density of 75% was initially measured for both drying and wetting processes. The hydraulic conductivity function (HCF) and suction stress characteristic curve (SSCC) were subsequently estimated. Under the rainfall-induced infiltration conditions, transient seepage analysis of an unsaturated infinite slope was performed using the finite element analysis program, SEEP/W. Based on these results, the stability of an unsaturated infinite slope under rainfall-induced infiltration conditions was examined in relation to suction stress. According to the results, the negative pore-water pressure and water content within the slope soil changed over time due to the infiltration. In addition, the variation of the negative pore-water pressure and water content led to a variation in suction stress and a subsequent change in the slope's factor of safety during the rainfall period.

Effect of extraction conditions on the stability and safety of sericin

  • Ji Hae, Lee;Hyun-Bok, Kim;HaeYong, Kweon
    • International Journal of Industrial Entomology and Biomaterials
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    • 제45권2호
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    • pp.93-98
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    • 2022
  • To assess the feasibility of silk sericin for non-textile application, the storage stability and biological safety of sericin were examined. It was extracted at 37℃, 70℃, 100℃, and 121℃ for 1, 3, and 5 h to elucidate the effect of extraction condition on the stability and safety of silk sericin. The solubility was increased till approximately 26% with extraction temperature of 121℃ for 1 h. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that the molecular weight distribution depended on the extraction conditions. Extracted sericin displayed typical UV absorption bands upon spectrometric analysis. To examine the reproducibility of its obtained conformation, sericin was extracted thrice and its circular dichroism (CD) spectra was measured each time. Most CD spectra showed reproducibility regardless of temperature and time except under 100℃ extraction condition. The diversity of CD spectrum showed gradual reduction and was finally coincident with extraction time from 1 to 5 h. Notably, sericin has a negative peak of approximately 200 nm attributed to random coil conformation, regardless of extraction condition. However, at the 100℃ extraction condition, sericin showed both bands to be negative bands of approximately 200 and 220 nm, respectively. Sericin was centrifuged to determine the stability of storage conditions. The sericin extracted at 100℃ and 121℃ for 1 h was found to form gel rapidly within 1 h, but at 121℃ condition, the gel fraction was approximately 20% within 1 h which retained its phase regardless of storage time. The gel fraction of sericin extracted at 100℃ for 5 h increased with time, however at the 121℃ for 5 h condition, the gel fraction was measured to be less than 10% regardless of increase in storage time. PetriflimTM AC plates test showed that sericin was safe from aerobic bacteria activity by extraction under high temperature.

정상인과 신체장애자의 성격특성이 의복행동에 미치는 영향 (Clothing Behavior Related to Selected Personality Traits of the Normal and Disabled Females)

  • 이순화;이명희
    • 한국의류학회지
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    • 제13권4호
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    • pp.347-356
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    • 1989
  • The purpose of this study was to investigate the relationships between personality traits and clothing behavior of the normal and disabled females, and to find out the difference in clothing behavior of the two groups. Questionaires for clothing behavior were chosen from the items which had been used in previous studies, and the items were selected on the basis of Cronbach's Alpha Reliability Coefficient. Clothing behavior was composed of four variables: aesthetics; comfort; modesty; and satisfaction. For measurement of 3 personality traits (emotional stability, sociability, and superiority), a portion of 'Personality Inventory' b) Sangro Lee, Changjin Byeon, and Wuigyo Jin was used. Samples were 286 females in Seoul, of whom 110 were normal high school girls, 86 were norma1 college women, 41 were disabled high school girls, and 49 were disabled college women. The data were analyzed using F-test, F-test, and correlation coefficient. The results of the study were the followings: 1. There were meaningful relationships between personality traits and clothing behavior 1) Stability had negative relations to aesthetics and modesty and positive relation to satisfaction. In the case of the normal, stability had no relation to comfort, but in the case of the disabled, it had positive relation to comfort. 2) The sociability had positive relations to aesthetics and satisfaction. 3) The superiority had negative relation to modesty, it had positive relation to satisfaction. The superiority of the normal had negative relation to comfort, whereas the superiority of the disabled had positive relation to comfort. 2. There was a difference in the clothing aesthetics between the normal and the disabled. 3. In case of the normal, college women regarded comfort less important than high school girls. In case of the disabled, college women regarded comfort more important than high school girls. 4. In upper class, there was no difference on the clothing comfort between the normal and the disabled. But there was difference on comfort between the normal and the disabled in low class.

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저소득층의 물리적 자원의 상실 및 획득이 안녕감에 미치는 영향과 경제적 안정의 매개 역할 (The Influence of Physical Resource Loss and Gain on Well-Being of People in Low-Income and the Mediating Role of Economic Stability)

  • 박선영
    • 한국사회복지학
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    • 제65권2호
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    • pp.335-356
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    • 2013
  • 이 연구는 저소득층이 겪는 물리적 자원에서의 상실과 획득이 안녕감에 어떠한 영향을 주는지 그리고 이들이 경제환경과 상호작용하며 경험하는 경제적 안정감이 그러한 상실 및 획득의 영향을 받아 안녕감에 어떠한 역할을 하는지를 탐색하고자 하였다. 이에 자활센터를 이용하는 저소득층 남녀 성인 254명을 대상으로 물리적 자원의 상실과 획득, 경제안정, 안녕감의 수준을 살펴보고, 자원의 상실 및 획득 각각이 안녕감에 영향을 주는 관계와 이 관계에서 경제안정 수준이 보이는 매개역할을 구조방정식모형 분석으로 검토하였다. 주요 연구결과는 첫째, 참여자들은 물리적 자원을 약간 잃거나 얻은 수준이고 획득이 상대적으로 높았다. 둘째, 경제안정 및 안녕감과의 관계에서 자원상실은 유의한 부적관계를, 획득은 유의한 정적 관계를 보였다. 셋째, 자원상실은 경제안정과 안녕감 각각에 대해 유의한 부적인 직접효과를 보인 한편 경제안정의 감소를 통해 안녕감을 감소시키는 간접효과도 유의하였다. 끝으로, 자원획득 역시 경제안정과 안녕감 각각에 대해 유의한 직접효과를 보이고 또 경제안정을 통한 정적인 간접효과가 유의하여 자원상실과 획득 두 모형 모두에서 부분매개모형이 지지되었다. 이러한 결과에 기초하여 사회복지실천에서 저소득층 성인의 생활과 밀접히 관련되는 물리적 자원의 상실 및 획득, 경제안정, 안녕감을 활용할 방안과 조사연구에서 가질 수 있는 함의를 찾고 제언하였다.

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A STUDY FOR DEVELOPMENT OF FILM NEGATIVE IN BULK REACTION CASE

  • Ha, Sung-N.;Park, Jung-Joon
    • Journal of applied mathematics & informatics
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    • 제26권1_2호
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    • pp.365-374
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    • 2008
  • We study a mathematical modeling for development of film negative and concentrate the bulk reaction problem. We prove nonnegativeness of developer, coupler and dye function in two dimensional case. Also we prove stability of our numerical scheme. Finally, we discuss numerical example which have specified constants.

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