• Title/Summary/Keyword: Instability

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Recent Changes in Summer Precipitation Characteristics over South Korea (최근 한반도 여름철 강수특성의 변화)

  • Park, Chang-Yong;Moon, Ja-Yeon;Cha, Eun-Jeong;Yun, Won-Tae;Choi, Young-Eun
    • Journal of the Korean Geographical Society
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    • v.43 no.3
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    • pp.324-336
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    • 2008
  • This paper examines the recent changes of summer precipitation in the aspect of temporal and spatial features using long-term($1958{\sim}2007$) observed station data over South Korea. tong-term mean summer precipitation has revealed two precipitation peaks during summer(June to September); one is the Changma as the first peak, and the other is the post-Changma as the second peak. During the Changma period, the spatial distribution of the maximum precipitation areas is determined by the prevailing southwesterlies and the quasi-stationary front, which results in large amount of precipitation at the windward side of mountain regions over South Korea. However during the post-Changma period, the spatial distribution of the maximum precipitation areas is determined by the lower tropospheric circulation flows from the west and the southeast around the Korean peninsula, and the weather phenomena such as Typhoons, convective instability, and cyclones which are originated from the Yangtze river. The larger amount of precipitation is founded on the southern coastal region and mountain and coastal areas in Korea during the second peak. Time series of total summer precipitation shows a steady increase and the increasing trend is more obvious during the recent 10 years. Decadal variation in summer precipitation indicates a large increase of precipitation, especially in the recent 10 years both in the Changma and the post-Changma period. However, the magnitude of change and the period of the maximum peak presents remarkable contrasts among stations. The most distinct decadal change occurs at Seoul, Busan, and Gangnueng. The precipitation amount is increasing significantly during the post-Changma period at Gangnueng, while the precipitation increases in the period between two maximum precipitation peaks during summer at Seoul and Busan.

Statistical Study of the Ferguson's Angle, Lumbar Gravity Line and Lumbar Lordotic Angle in HIVD Patients. (요추간판탈출증 환자의 요천각, 요추중력중심선 및 요추전만각의 통계적 관찰)

  • Koh, Dong-Hyun;Hong, Soon-Sung;Lee, Jin-Ho;Jung, Sung-Yub;Shin, Joon-Shik
    • The Journal of Churna Manual Medicine for Spine and Nerves
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    • v.2 no.2
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    • pp.17-32
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    • 2007
  • Objectives : The lumbosacral joint is unstable area from an anatomical viewpoint, while it is also a very mobile area in ordinary life, so that clinically major causes of low back pain originate in this joint. The purpose of this study is to assess the difference of the Ferguson's angles, Lumbar gravity lines, Lumbar lordotic angles among Herniated of Intervertebral Disc(HIVD) patients. Methods : We analyzed the lateral view of lumbar spine checked at erect position on 88 patients who had been diagnosed as HIVD by Magnetic Resonance Imaging(MRI). We investigated the Ferguson's angle, Lumbar gravity line, Lumbar lordotic angle on X-ray film. Results and Conclusions : In the acute lumbago group the Ferguson's angle had a tendency to decrease, while in the chronic group it had a tendency to increase. In the acute lumbago group the Lumbar gravity line fell in front of the normal range(sacrum), while in the chronic group it fell behind the normal range(sacrum). In the acute lumbago group the Lumbar lordotic angle usually decreased, while in the chronic group it increased. The Ferguson's angle and the Lumbar gravity line, the Ferguson's angle and the Lumbar lordotic angle, the Lumbar gravity line and Lumbar lordotic angle each had a positive realtionship. The Ferguson's angle, the Lumbar gravity line and the Lumbar lordotic angle was less influenced by the level of HIVD and was more influenced by how long the patient had the pain. The correlationship between each factor was less in the chronic lumbago group than the acute group. In the chronic lumbago group the instability of the lumbosacral joint increased, while in the acute group the compression of the weight on the sacrum increased.

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A CASE OF CLOZAPINE TRIAL FOR A MANIC EPISODE SUFFERED BY AN ADOLESCENT RECOVERING FROM NEUROLEPTIC MALIGNANT SYNDROME (신경이완제 악성증후군 회복후 지속되는 조증에 Clozapine을 사용한 청소년 환자 1례)

  • Cho, Soo-Churl;Hong, Kang-E;Kim, Yong-Sik;Chung, Sun-Ju;Bahn, Geon-Ho
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.9 no.2
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    • pp.247-252
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    • 1998
  • Neuroleptic malignant syndrome(NMS) is an acute, potentially fatal, idiosyncratic reaction to neuroleptic medication. Early recognition and intensive care are crucial. An important issue is whether NMS will recur after initial recovery and subsequent use of neuroleptic medication. The authors presented with a male adolescent who had suffered a bipolar disorder manic episode and been taking clozapine after recovering from MNS. He had been admitted into a psychiatric ward once before and similarly diagnosed. On the second admission, he showed muscle rigidity, autonomic instability, mild fever, severe diaphoresis, and altered mental status on the fourth hospital day following a haloperidol injection. He was diagnosed with NMS, according to the clinical signs and laboratory data. After the use of antipsychotics was discontinued, he was moved to intensive care unit and given dantrolene. His condition began to improve about 48 hours after the onset of NMS. Due to manic behavior, he returned to the psychiatric ward. On the 21 st hospital day, clozapine was administered to counter the manic symptoms. The final dose was 350mg and showed good remission signs without further recurrence of NMS.

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Fresh Water Flume Analysis Using an Unstructured Grid Ocean Circulation Model (비정규격자계 해양순환 모델을 이용한 하구에서의 담수 유출분석)

  • Hwang, Jin-Hwan;Park, Young-Gyu
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.12 no.4
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    • pp.227-234
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    • 2009
  • Using a finite volume ocean circulation model based on an unstructured grid (FVCOM), we studied the structure of a fresh water bulge that influences on the Region Of Freshwater Influence. Fresh water discharged a river forms a coastal boundary current to the righthand side and a cyclonically circulation freshwater bulge that grows with time. In the middle of the bulge, vertical motions bring fresh water to the bottom. When tidal motions are included, the bulge disappears while the boundary currents becomes wider. Through a simple comparison of areas occupied low salinity water we quantified vertical and horizontal mixing due to the tide and showed that the tidal motion enhances the vertical mixing. During the first few tidal cycles right after the onset of the river discharge, due to tidal excursion the horizontal mixing becomes stronger. The vertical mixing by the tide mixes the fresh water After a certain time the water around the river mouth is well mixed and the horizontal excursion of the fresh water near the river mouth does not have much effect on the horizontal mixing. When there is no tidal motion horizontal mixing is mainly by the inertial instability at the surface and the horizontal mixing becomes stronger over time.

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Anterior Cervical interbody Fusion with Cervical Spine Locking Plate (경추 물림 금속판을 이용한 경추 전방추체간 유합술)

  • Park, Joo-Tae;Ahn, Gil-Young;Lee, Young-Tae;Ahn, Myun-Whan
    • Journal of Yeungnam Medical Science
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    • v.14 no.1
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    • pp.209-219
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    • 1997
  • Objectives: Anterior approach to achieve arthrodesis of the cervical spine has become a widely accepted and often-used approach since its earliest reports by Bailey and Badgley, Smith and Robinson and Cloward. However, anterior interbody fusion in the presence of the posterior instability may be complicated by the bone graft dislodgement, kyphotic defomity or nonunion. As an attemp to prevent this undesirable complication, additional methods such as skeletal traction, halo appratus or even posterior fusion has been utilized. Therefore, The cervical spine locking plate(CSLP) with the anterior intervertebral body bone grafting provide immediate cervical stabilization and widely successful in achieving fusion. Material and methods: This study analysed 14 patients who underwent a single anterior procedure and application of CSLP for the treatment of the cervical spinal disorder. Eleven patients were disc herniations and three patients were traumatic lesion. The average age of the patient was 47 years and the mean follow up periods was 20 months ranging from 13 to 27 months. Results: Ambulation was started 2nd day after the operation with the aid of the Philadelpia orthoses. Bone union was observed 13 cases on average 12 weeks after operation. The one case was nonunion with plate breakage without clinical symptom. Conclusion: Anterior fusion with CSLP are thought to be a safe and valuable method for treating cervical spine disorder.

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A Study on Factors Affecting Workable Youth's Poverty Transition -Focused on Employment Stability and Employment Status- (청년층의 근로빈곤 요인에 관한 연구 -고용불안정과 고용상태가 빈곤이행에 미치는 영향을 중심으로-)

  • Byun, Geum-Sun
    • Korean Journal of Social Welfare
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    • v.64 no.3
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    • pp.257-279
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    • 2012
  • This study examined how employment status changes affects poverty transition of workable youth using 3years panel data from KoWePS(Korea Welfare Panel Study, 2007-2009). Findings and implications of this study as follows. First, although relative poverty rate of aged 18-34 is lower than other age groups, significant amount of youth experienced poverty once in 2007-2009(14.59%). This means that there are some of youth suffering for poverty and the aspect of youth poverty is very dynamic. Second, much of workable poor of youth had high level of education(45.9% in 2009) and they were unemployed or inactive in labor market(55.3% in 2009). These findings consistent with previous studies of youth poverty or youth employment. Third, workable youth who had changed employment status from employed to unemployed or inactive in labor market were likely to enter poverty and less likely to exit from poverty. Moreover youth who were non-standard employed had more possibility to be poor and less possibility to be not poor. These show that employment instability makes youth vulnerable to economic hardship, poverty. The result of this study suggest that anti-poverty programs which are related with the work-related programs and active labor market policy, should consider workable youth who have high level of human capital comparing other ordinary working poor. Because of much of youth are not poor in fixed time point, they can't be supported from existing social assistance program, like National Basic Livelihood Protection Program. As youth who experienced poverty in changing time need social support to prevent long-term poverty, government should contemplate adopting assistance program for workable poor youth.

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Effects of Neutral Particle Beam on Nano-Crystalline Silicon Thin Film Deposited by Using Neutral Beam Assisted Chemical Vapor Deposition at Room Temperature

  • Lee, Dong-Hyeok;Jang, Jin-Nyoung;So, Hyun-Wook;Yoo, Suk-Jae;Lee, Bon-Ju;Hong, Mun-Pyo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.254-255
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    • 2012
  • Interest in nano-crystalline silicon (nc-Si) thin films has been growing because of their favorable processing conditions for certain electronic devices. In particular, there has been an increase in the use of nc-Si thin films in photovoltaics for large solar cell panels and in thin film transistors for large flat panel displays. One of the most important material properties for these device applications is the macroscopic charge-carrier mobility. Hydrogenated amorphous silicon (a-Si:H) or nc-Si is a basic material in thin film transistors (TFTs). However, a-Si:H based devices have low carrier mobility and bias instability due to their metastable properties. The large number of trap sites and incomplete hydrogen passivation of a-Si:H film produce limited carrier transport. The basic electrical properties, including the carrier mobility and stability, of nc-Si TFTs might be superior to those of a-Si:H thin film. However, typical nc-Si thin films tend to have mobilities similar to a-Si films, although changes in the processing conditions can enhance the mobility. In polycrystalline silicon (poly-Si) thin films, the performance of the devices is strongly influenced by the boundaries between neighboring crystalline grains. These grain boundaries limit the conductance of macroscopic regions comprised of multiple grains. In much of the work on poly-Si thin films, it was shown that the performance of TFTs was largely determined by the number and location of the grain boundaries within the channel. Hence, efforts were made to reduce the total number of grain boundaries by increasing the average grain size. However, even a small number of grain boundaries can significantly reduce the macroscopic charge carrier mobility. The nano-crystalline or polymorphous-Si development for TFT and solar cells have been employed to compensate for disadvantage inherent to a-Si and micro-crystalline silicon (${\mu}$-Si). Recently, a novel process for deposition of nano-crystralline silicon (nc-Si) thin films at room temperature was developed using neutral beam assisted chemical vapor deposition (NBaCVD) with a neutral particle beam (NPB) source, which controls the energy of incident neutral particles in the range of 1~300 eV in order to enhance the atomic activation and crystalline of thin films at room temperature. In previous our experiments, we verified favorable properties of nc-Si thin films for certain electronic devices. During the formation of the nc-Si thin films by the NBaCVD with various process conditions, NPB energy directly controlled by the reflector bias and effectively increased crystal fraction (~80%) by uniformly distributed nc grains with 3~10 nm size. The more resent work on nc-Si thin film transistors (TFT) was done. We identified the performance of nc-Si TFT active channeal layers. The dependence of the performance of nc-Si TFT on the primary process parameters is explored. Raman, FT-IR and transmission electron microscope (TEM) were used to study the microstructures and the crystalline volume fraction of nc-Si films. The electric properties were investigated on Cr/SiO2/nc-Si metal-oxide-semiconductor (MOS) capacitors.

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Relations between emotional labor and job stress among some dental hygienists (일부 치과위생사의 감정노동과 직무스트레스와의 관계)

  • Yoon, Song-Uk;Kim, Jung Sook
    • Journal of Korean society of Dental Hygiene
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    • v.11 no.2
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    • pp.179-188
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    • 2011
  • Objectives : The study set out to analyze correlations between emotional labor and job stress among dental hygienist, who have direct and lasting relationships with patients in dental clinic, and provide basic data to resolve stressors and manage stress. Methods : A survey was taken among dental hygienists working at dental clinics, and 200 questionnaires were used in analysis. The gathered data were put to Cronbach's alpha with the SPSS WIN12.0 program to test the reliability of the inventories to measure their emotional labor and job stress. In addition, correlation analysis was conducted to examine relations between the items of emotional labor and those of job stress along with regression analysis to examine relations between emotional labor and job stress. Finally, t-test and One-way ANOVA were conducted to test mean differences in the job stress items according to the degrees of emotional labor with the statistical significance level set at 0.05. Results : 1. The measurement tool used in the study recorded 0.7 for all the areas of Cronbach's alpha for internal reliability and thus achieved high reliability. 2. The overall mean of emotional labor was 2.74, which indicates that the dental hygienists had 'average' or higher stress for emotional labor. 3. Emotional labor had statistically significant relations with educational background, place of work, motivation to choose to be a dental hygienist, and religion of their general characteristics. 4. There was statistical significance in relations between general characteristics and job stress according to educational background, position at work, and experience with change of occupation. 5. The correlations between emotional labor and the stress areas were analyzed. As a result, emotional labor was in positive(+) correlations with job demand, lack of job autonomy, relational conflict, job instability, organizational system, and corporate culture. In addition, regression analysis was conducted to test causal relations between emotional labor and job stress. The results indicate that there were positive(+) influences between emotional labor and job stress. Conclusions : The results show that emotional labor can serve as a mediating variable for job stress in dental clinic. Thus both dental clinics and dental hygienists need to have ways to deal with job stress derived from emotional labor in which they are forced to process their emotions according to the dental clinics' demands, properly. The study will hopefully trigger ongoing follow-up researches on the deployment of dental hygienists according to their job characteristics and the situational variables to alleviate the negative results of emotional labor.

Clinical Application of Autologous Adipose Tissue Derived Mesenchymal Stem Cells in Five Dogs with Stifle Joint Osteoarthrosis (무릎 골관절증을 보이는 개에서 자가지방유래 중배엽성 줄기세포 치료 다섯 증례)

  • Yoon, Hun-Young;Kang, Dong Jun;Lee, Soo-Han;Jeong, Soon-Wuk;Chung, Byung-Hyun
    • Journal of Veterinary Clinics
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    • v.31 no.3
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    • pp.253-257
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    • 2014
  • Five dogs presented with a history of pelvic limb lameness. On physical examination of the stifle joints, five dogs had pain, lameness, patellar luxation, or ligamentous instability. Craniocaudal and mediolateral radiographic projections revealed osteophytes or subchondral cystic lesions on the stifle joints. Based on a previously described Osteoarthrosis (OA) scoring technique, five dogs showed high OA scores. Combination of surgery and implantation of autologous adipose tissue derived mesenchymal stem cells (aAT-MSCs) or percutaneous injection of aAT-MSCs was determined with informed consent. $1{\times}10^6$ aAT-MSCs suspended in PBS was injected in the stifle joints. The follow-ups were completed 12 months after surgery. The follow-up information was based on physical examination by veterinarians. The lameness, pain on manipulation, and OA scores improved six or 12 months after implantation of aAT-MSCs. There was a radiographic evidence of decreased osteophytes and subchondral cystic lesions. These results suggest that implantation of aAT-MSCs can be considered an option for management of cases of OA in the stifle joints.

Vertical Atmospheric Structure and Sensitivity Experiments of Precipitation Events Using Winter Intensive Observation Data in 2012 (2012년 겨울철 특별관측자료를 이용한 강수현상 시 대기 연직구조와 민감도 실험)

  • Lee, Sang-Min;Sim, Jae-Kwan;Hwang, Yoon-Jeong;Kim, Yeon-Hee;Ha, Jong-Chul;Lee, Yong-Hee;Chung, Kwan-Young
    • Atmosphere
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    • v.23 no.2
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    • pp.187-204
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    • 2013
  • This study analyzed the synoptic distribution and vertical structure about four cases of precipitation occurrences using NCEP/NCAR reanalysis data and upper level data of winter intensive observation to be performed by National Institute of Meteorological Research at Bukgangneung, Incheon, Boseong during 63days from 4 JAN to 6 MAR in 2012, and Observing System Experiment (OSE) using 3DVAR-WRF system was conducted to examine the precipitation predictability of upper level data at western and southern coastal regions. The synoptic characteristics of selected precipitation occurrences were investigated as causes for 1) rainfall events with effect of moisture convergence owing to low pressure passing through south sea on 19 JAN, 2) snowfall events due to moisture inflowing from yellow sea with propagation of Siberian high pressure after low pressure passage over middle northern region on 31 JAN, 3) rainfall event with effect of weak pressure trough in west low and east high pressure system on 25 FEB, 4) rainfall event due to moisture inflow according to low pressures over Bohai bay and south eastern sea on 5 MAR. However, it is identified that vertical structure of atmosphere had different characteristics with heavy rainfall system in summer. Firstly, depth of convection was narrow due to absence of moisture convergence and strong ascending air current in middle layer. Secondly, warm air advection by veering wind with height only existed in low layer. Thirdly, unstable layer was limited in the narrow depth due to low surface temperature although it formed, and also values of instability indices were not high. Fourthly, total water vapor amounts containing into atmosphere was small due to low temperature distribution so that precipitable water vapor could be little amounts. As result of OSE conducting with upper level data of Incheon and Boseong station, 12 hours accumulated precipitation distributions of control experiment and experiments with additional upper level data were similar with ones of observation data at 610 stations. Although Equitable Threat Scores (ETS) were different according to cases and thresholds, it was verified positive influence of upper level data for precipitation predictability as resulting with high improvement rates of 33.3% in experiment with upper level data of Incheon (INC_EXP), 85.7% in experiment with upper level data of Boseong (BOS_EXP), and 142.9% in experiment with upper level data of both Incheon and Boseong (INC_BOS_EXP) about accumulated precipitation more than 5 mm / 12 hours on 31 January 2012.