• Title/Summary/Keyword: instability analysis

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Design of High-Speed Multi-Layer PCB for Ultra High Definition Video Signals (UHD급 영상구현을 위한 다층인쇄회로기판의 특성 임피던스 분석에 관한 연구)

  • Jin, Jong-Ho;Son, Hui-Bae;Rhee, Young-Chul
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.7
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    • pp.1639-1645
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    • 2015
  • In UHD high-speed video transmission system, when a signal within certain frequency region coincides electrically and structurally, the system becomes unstable because the energy is concentrated, and signal flux is interfered and distorted. For the instability, power integrity analysis should be conducted. To remove the signal distortion for MLB, using a high-frequency design technique for EMI phenomenon, EMI which radiates electromagnetic energy fluxed into power layer was analyzed considering system stabilization. In this paper, we proposed an adaptive MLB design method which minimizes high-frequency noise in MLB structure, enhances signal integrity and power integrity, and suppresses EMI. The characteristic impedance for multi-layer circuit board proposed in this study were High-Speed Video Differential Signaling(HSVDS) line width w = 0.203, line gap d = 0.203, beta layer height h = 0.145, line thickness t = 0.0175, dielectric constant εr = 4.3, and characteristic impedance Zdiff = 100.186Ω. When high-speed video differential signal interface board was tested with optimized parameters, the magnitude of Eye diagram output was 672mV, jittering was 6.593ps, transmission frequency was 1.322GHz, signal to noise was 29.62dB showing transmission quality improvement of 10dB compared to previous system.

Analysis of Positive Bias Temperature Instability Characteristic for Nano-scale NMOSFETs with La-incorporated High-k/metal Gate Stacks (La이 혼입된 고유전체/메탈 게이트가 적용된 나노 스케일 NMOSFET에서의 PBTI 신뢰성의 특성 분석)

  • Kwon, Hyuk-Min;Han, In-Shik;Park, Sang-Uk;Bok, Jung-Deuk;Jung, Yi-Jung;Kwak, Ho-Young;Kwon, Sung-Kyu;Jang, Jae-Hyung;Go, Sung-Yong;Lee, Weon-Mook;Lee, Hi-Deok
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.24 no.3
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    • pp.182-187
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    • 2011
  • In this paper, PBTI characteristics of NMOSFETs with La incorporated HfSiON and HfON are compared in detail. The charge trapping model shows that threshold voltage shift (${\Delta}V_{\mathrm{T}}$) of NMOSFETs with HfLaON is greater than that of HfLaSiON. PBTI lifetime of HfLaSiON is also greater than that of HfLaON by about 2~3 orders of magnitude. Therefore, high charge trapping rate of HfLaON can be explained by higher trap density than HfLaSiON. The different de-trapping behavior under recovery stress can be explained by the stable energy for U-trap model, which is related to trap energy level at zero electric field in high-k dielectric. The trap energy level of two devices at zero electric field, which is extracted using Frenkel-poole emission model, is 1,658 eV for HfLaSiON and 1,730 eV for HfLaON, respectively. Moreover, the optical phonon energy of HfLaON extracted from the thermally activated gate current is greater than that of HfLaSiON.

A Study on the Causes of Elderly Crime and Its Countermeasures in the Transition of Elderly Society (초고령사회 전환기에 노인범죄 발생원인과 그 대책에 관한 연구)

  • Yang, Jae Yeol;Kim, Sang Su;Lee, Ju Yeon
    • Korean Security Journal
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    • no.61
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    • pp.307-332
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    • 2019
  • Recently, our society has been changing its population structure due to low birth rate along with the extension of life span due to the development of medical environment and improvement of living environment. It was not long before the population became older, and the problem of the elderly was amplified by generational conflict. The current generation of senior citizens could not afford to prepare for their own retirement income due to their children's education, marriage and housing problems, and is a generation alienated from the benefits of public income security. In addition, not only are they in poverty with rapid industrialization, informatization and economic instability, but they are also threatened with livelihood. The increase in elderly crimes arising from the elderly, who are less adaptable to our society dominated by materialism, is being highlighted as a new social issue. In this study, we are going to analyze the causes of violent and violent senior citizens' crimes in quality along with quantitative growth, and present criminal situations and preventive measures using 10 years of data, judging that this is a time when a national response is needed through a social discussion on crimes committed by senior citizens in our society, where the pace of aging is unprecedentedly fast in the world In order to achieve this research objective, various opinions and statistical data of our society where the standards of senior citizens are changing were reviewed, and analysis of crimes was conducted on literature utilizing data of the Supreme Public Prosecutor's Office, the National Police Agency, and the National Statistical Office, recent press releases, and existing research materials. In this study, we will diagnose crimes committed by senior citizens in various aspects, including the characteristics of the elderly and the view of the elderly in the present society, and explore the direction of development for the prevention of future crimes as well.

Spinocerebellar ataxia 7 (SCA7) (척수소뇌성 운동실조증 제7형)

  • Seon-Yong, Jeong;Seok-Hun, Jang;Hyon-J., Kim
    • Journal of Genetic Medicine
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    • v.4 no.1
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    • pp.22-37
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    • 2007
  • The autosomal dominant spinocerebellar ataxias (SCAs) are a group of neurodegenerative diseases, clinically and genetically heterogeneous, characterized by degeneration of spinocerebellar pathways with variable involvement of other neural systems. At present, 27 distinct genetic forms of SCAs are known: SCA1-8, SCA10-21, SCA23, SCA25-28, DRPLA (dentatorubral-pallidoluysian atrophy), and 16q-liked ADCA (autosomal dominant cerebellar ataxia). Epidemiological data about the prevalence of SCAs are restricted to a few studies of isolated geographical regions, and most do not reflect the real occurrence of the disease. In general a prevalence of about 0.3-2 cases per 100,000 people is assumed. As SCA are highly heterogeneous, the prevalence of specific subtypes varies between different ethnic and continental populations. Most recent data suggest that SCA3 is the commonest subtype worldwide; SCA1, SCA2, SCA6, SCA7, and SCA8 have a prevalence of over 2%, and the remaining SCAs are thought to be rare (prevalence <1%). In this review, we highlight and discuss the SCA7. The hallmark of SCA7 is the association of hereditary ataxia and visual loss caused by pigmentary macular degeneration. Visual failure is progressive, bilateral and symmetrical, and leads irreversibly to blindness. This association represents a distinct disease entity classified as autosomal dominant cerebellar ataxia (ADCA) type II by Harding. The disease affectsprimarily the cerebellum and the retina by the moderate to severe neuronal loss and gliosis, but also many other central nervous system structures as the disease progresses. SCA7 is caused by expansion of an unstable trinucleotide CAG repeat in the ATXN7 gene encoding a polyglutamine (polyQ) tract in the corresponding protein, ataxin-7. Normal ATXN7 alleles contain 4-35 CAG repeats, whereas pathological alleles contain from 36->450 CAG repeats. Immunoblott analysis demonstrated that ataxin-7 is widely expressed but that expression levels vary among tissues. Instability of expanded repeats is more pronounced in SCA7 than in other SCA subtypes and can cause substantial lowering of age at onset in successive generations termed ‘anticipation’ so that children may become diseased even before their parents develop symptoms. The strong anticipation in SCA7 and the rarity of contractions should have led to its extinction within a few generations. There is no specific drug therapy for this neurodegenerative disorder. Currently, therapy remains purely symptomatic. Cellular models and SCA7 transgenic mice have been generated which constitute valuable resources for studying the disease mechanism. Understanding the pathogenetic mechanisms of neurodegeneration in SCAs should lead to the identification of potential therapeutic targets and ultimately facilitate drug discovery. Here we summarize the clinical, pathological, and genetic aspects of SCA7, and review the current understanding of the pathogenesis of this disorder. Further, we also review the potential therapeutic strategies that are currently being explored in polyglutamine diseases.

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Prenatal diagnosis of a de novo ring chromosome 11

  • Park, Ju-Yeon;Lee, Moon-Hee;Lee, Bom-Yi;Lee, Yeon-Woo;Ryu, Hyun-Mee;Park, So-Yeon
    • Journal of Genetic Medicine
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    • v.4 no.1
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    • pp.80-83
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    • 2007
  • A 36-year-old pregnant woman was referred for amniocentesis at 19.5 weeks gestation because of advanced maternal age and evidence of increased risk for Edward syndrome in the maternal serum screening test. Cytogenetic analysis of the cultured amniotic fluid cells revealed mosaicism for ring chromosome 11: 46,XX,r(11)[65]/ 45,XX,-11[16]/ 46,XX [34]. Parental karyotypes were normal. A targeted ultrasound showed intrauterine grow th restriction (IUGR). Cordocentesis was performed to characterize the ring chromosome and to rule out tissue specific mosaicism. Karyotype was confirmed as 46,XX,r(11) (p15.5q24.2)[229]/45,XX,-11[15]. And a few new form of ring w ere detected in this culture. The deletion of subtelomeric regions in the ring chromosome were detected by fluorescent in situ hybridization (FISH). The pregnancy was terminated. The fetal autopsy showed a growth-retarded female fetus with rocker bottom feet. We report a case of prenatally detected a de novo ring chromosome 11.

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Molecular Cloning of cDNA Encoding a Putative Eugenol Synthase in Tomato (Solanum lycopersicum 'Micro-Tom') and Prediction of 3D Structure and Physiochemical Properties (토마토 'Micro-Tom' 과실의 eugenol synthase 유전자 클로닝, 단백질의 3차 구조 및 생리화학적 특성 예측)

  • Kang, Seung-Won;Seo, Sang-Gyu;Lee, Tai-Ho;Lee, Gung-Pyo
    • Journal of agriculture & life science
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    • v.46 no.4
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    • pp.9-20
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    • 2012
  • Eugenol is a volatile compound synthesized by eugenol synthase in various plants and belongs to phenylpropene compounds. However, characteristics of eugenol synthase in tomato has not been known. Therefore, we cloned a full length cDNA of a putative eugenol synthase from tomato 'Micro-Tom' using rapid amplification of cDNA ends (RACE) technique and named a clone SlEGS. Open reading frame of SlEGS was 921bp long and its deduced amino acid sequence was 307bp. The BLAST analysis indicated that SlEGS shared high similarity with PhEGS1 (67.1%) and CbEGS2 (69.4%). Amino acid composition of SlEGS was determined by CLC genomics workbench tool and 3D structure of SlEGS was constructed by homology modeling using Swiss-PDB viewer and validated using PROCHECK and ProSA-web tool. In addition, the physiochemical properties of SlEGS was evaluated using ExPASy's ProtParam tool. Molecular weight was 33.93kDa and isoelectric point was 5.85 showing acidic nature. Other properties such as extinction coefficient, instability index, aliphatic index, and grand average hydropathy was also analyzed.

A Study on the Safety Management Methods of Micro-Gas Engine Combined Heat and Power System (소형 가스엔진 열병합발전 시스템의 안전관리 방안에 관한 연구)

  • Kim, So-Hyun;Kim, Min-Woo;Lee, Eun-Kyung;Lee, Jung-Woon
    • Journal of the Korean Institute of Gas
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    • v.22 no.6
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    • pp.76-89
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    • 2018
  • The distribution of the combined heat and power system is active as a solution to the instability of energy supply and environmental pollution caused by continuous industrial development. In Korea, the safety standards for combined heat and power system using a gas engine are insufficient therefore the study on this is needed. In this study, the safety performance and structural/material assessment items of domestic and international standards applied to the combined heat and power system were analyzed to carry out a standardization study on safety performance applicable to 20 kW gas engine combined heat and power system. In addition, the safety performance assessment (plan) of the gas engine combined heat and power system was derived by performing risk analysis and risk assessment using HAZOP. Assessment items include engine ignition systems related to safety performance, piping tight performance, watering and temperature rise performance, combustion performance, electrical efficiency, thermal efficiency, overall efficiency and humidity performance. Gas and water pipes, gas control and shut-off valves, durability, heat resistance, and cold resistance of metal or non-metallic materials related to the structure and materials of the gas engine combined heat and power systems.

Speech Evaluation Tasks Related to Subthalamic Nucleus Deep Brain Stimulation in Idiopathic Parkinson's Disease: A Review (특발성 파킨슨병의 시상밑부핵 심부뇌자극술 관련 말 평가 과제에 대한 문헌연구)

  • Kim, Sun Woo;Kim, Hyang Hee
    • 재활복지
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    • v.18 no.4
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    • pp.237-255
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    • 2014
  • Idiopathic Parkinson disease(IPD) is an neurodegenerative disease caused by the loss of dopamine cells in the substantia nigra, a region of midbrain. Its major symptoms are muscular rigidity, bradykinesia, resting tremor, and postural instability. An estimated 70~90% of patients with IPD also have hypokinetic dysarthria. Subthalamic nucleus deep brain stimulation (STN-DBS) has been reported to be successful in relieving the core motor symptoms of IPD in the advanced stages of the disease. However, data on the effects of STN-DBS on speech performance are inconsistent. A medline literature search was done to retrieve articles published from 1987 to 2012. The results were narrowed down to focus on speech performance under STN-DBS based perceptual, acoustic, and/or aerodynamic analyses. Among the 32 publications which dealt with speech performance after STN-DBS indicated improvement(42%), deterioration(29%), mixed results(26%), or no change(3%). The most favorite method was found to be based upon acoustic analysis by using a vowel prolongation and Unified Parkinson's Disease Rating Scale(UPDRS). For the purpose of verifying the effect of the STN-DBS, speech evaluation should be undertaken on all speech components such as articulation, resonance, phonation, respiration, and prosody by using a contextual speech task.

Qualitative Case Study on Psychological Difficulties Found In Each Divorce Decision Making Stage That Senescent Women Face in Their Early Stage of Elderly Life (초기노년기 여성이 경험한 이혼결정단계별 심리적 어려움에 관한 질적사례연구)

  • Moon, Jung Hwa;Kim, Mi Ra
    • Korean Journal of Family Social Work
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    • no.58
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    • pp.67-96
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    • 2017
  • The purpose of this study is to examine psychological difficulties that elderly women experience in each divorce decision making stage and they are shown by counselling cases made with elderly women who got divorced in their early stage of elderly life. For this purpose, total 18 counseling cases were collected from November 2012 to March 2013 and a qualitative analysis was made accordingly. The result of this study was made by analyzing meaningful subjects emerged in individual testimonies during a counseling process and it shows that the decision to divorce goes through stages such as , , , , , and . In addition, psychological difficulties experienced in a divorce decision process appear to be, , , , , , and . It is meaningful that this study provides counseling strategies for psychosocial support of the elderly women who go through difficulties in their divorce decision making process.

Quantitative Analysis of Snow Particles Using a Multi-Angle Snowflake Camera in the Yeongdong Region (영동지역에서 눈결정 카메라를 활용한 눈결정의 정량 분석)

  • Kim, Su-Hyun;Ko, Dae-Hong;Seong, Dae-Kyung;Eun, Seung-Hee;Kim, Byung-Gon;Kim, Baek-Jo;Park, Chang-Geun;Cha, Ju-Wan
    • Atmosphere
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    • v.29 no.3
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    • pp.311-324
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    • 2019
  • We employed a Multi-Angle Snowflake Camera (MASC) to quantitatively analyze snow particles at the ground level in the Yeongdong region of Korea. The MASC captures high-resolution photographs of hydrometeors from three angles and simultaneously measures fallspeed. Based on snowflake images of the several episodes in 2017 and 2018, we derived statistics of size, aspect ratio, orientation, complexity, and fallspeed of snow crystals, which generally showed similar characteristics to the previous studies in other regions of the world. Dominant snow crystal habits of January 22, 2018 generated by northerly were melted aggregates when 850 hPa temperature was about $-6{\sim}-8^{\circ}C$. Average fallspeed of snow crystals was $1.0m\;s^{-1}$ though its size gradually increased as temperature decreased. Another snowfall event (March 8, 2018) was driven by the baroclinic instability as accompanied with a deep trough. Snow crystal habits were largely rimed aggregates (complexity ~1.8) and melting particles of dark images. Meanwhile, in the extreme snowfall event whose snow rate was greater than $10cm\;hr^{-1}$ on January 20, 2017, main snow crystals appeared to be heavily rimed particles with relatively smaller size when convective clouds developed vertically up to 9 km in association with tropopause folding. MASC also could successfully measure a decrease in snow crystal size and an increase in riming degree after AgI seeding at Daegwallyeong on March 14, 2017.