• Title/Summary/Keyword: 흡인력

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Parameter Estimation of Groundwater Flow in Hillside Slopes Using Bayesian Approach (사면의 지하수 흐름에서 Bayesian 이론을 이용한 매개변수 추정)

  • 이인모;이주공;김영욱
    • Journal of the Korean Geotechnical Society
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    • v.17 no.2
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    • pp.51-57
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    • 2001
  • 지하수위의 상승에 따른 간극수압의 증가는 사면의 불안정을 야기할 수 있다. 그러나 모델링 오차, 계측오차, 모델변수의 불확실성 등과 같은 오차로 인하여 사면에서의 지하수위 변동을 예측하는 것은 매우 어렵다. 이러한 불확실성을 극복하고 지하수위 변동을 평가하기 위한 최적의 모델변수를 구하기 위하여 역해석 기법이 사용되고 있다. 본 논문에서는 사면에서의 지하수위 변동을 예측하기 위하여 포화대에서의 지하수 흐름과 불포화대에서의 지하수 흐름을 동시에 고려할 수 있는 수치해석 모델과 변수예측기법을 적용하였다. 따라서, 본 논문에서는 포화투수계수($K_{s}$ ), 포화흡인력($\psi$$_{e}$) 및 불포화 투수계수의 함수에 사용되는 경험적인 상수(b)를 주요 매개변수로 선정하여 역해석을 실시하였다. 그리고, 역해석 기법 가운데 Maximum Likelihood(MK), Maximum-A-Posterior(MAP) 및 Extended Bayesian Method(EBM)에 대하여 비교연구를 실시하였다. 위의 세가지 방법 가운데 EBM은 가상의 변수(Hyperparameter) $\beta$를 도입함으로써 현장계측치와 사전정보를 가장 잘 조화시키는 방법으로 다른 ML, MAP 보다 탁월한 방법인 것을 알 수 있었다.

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Anterior Tracheoplasty Using Glutaraldehyde-Soaked Autologous Pericardium -One Case Report- (글루타르알데하이드에 담근 자가심막을 이용한 전방기관성형술 -1례 보고-)

  • 이석열;송철민;장원호;박형주;이철세;이길노
    • Journal of Chest Surgery
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    • v.35 no.6
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    • pp.487-490
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    • 2002
  • A 60-year-old female was admitted to our hospital complaining of dyspnea. In the past history, she had received tracheal diversion due to recurrent aspiration after brain surgery and tracheostomy. Emergency three dimensional spiral tracheal computed tomograhpy revealed distal tracheal stenosis. The operation was performed by anterior tracheoplasty using glutaraldehyde-soaked autologous pericardium through median sternotomy. Herein we report a case of anterior tracheoplasty using glutaraldehyde-soaked autologous pericardium.

A Study on the Incidence of Thyroid Cancer in Gender Ultrasound (초음파검사에서 성별에 따른 갑상샘 암의 빈도에 관한 연구)

  • Kwak, Eun-Suk;Lim, Cheong-Hwan;Yang, Oh-Nam
    • Journal of radiological science and technology
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    • v.38 no.2
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    • pp.145-153
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    • 2015
  • Thyroid nodules are an endocrine disease often found in clinical practice, and patients with thyroid nodules found by chance have rapidly increased alongside development of thyroid ultrasound techniques for health examination purposes. This study analyzes the subjects' general characteristics, thyroid ultrasounds, and fine needle aspiration cytology in order to find out the relationship between male and female thyroid nodules and thyroid cancer frequency. An ultrasound examination of the thyroid was performed for 32,973 individuals who visited the K Hospital of Health Examination. Subjects have no history of thyroid disease and are 20 years old or over. Data of general characteristics, diabetes) was collected by a written survey completed by the subject, and the ultrasound of the thyroid(thyroid nodules existence, size, number) and FNAC was used to find out the malignancy rate. Frequency of patients with thyroid nodule was 4,611(26.1%) in men and 5,341(34.9%) in women between 32,973 individuals. Women's prevalence rate is significantly higher than men, and the prevalence rate significantly increased with age in men and women(p < 0.05). The prevalence of multiple nodules was significantly higher in women(43.5%) than in men(35.6%), and significantly increased with age in men and women(p < 0.05). The fine needle aspiration cytology was performed in 692(men 342, women 350) subjects who showed signs of malignancy through ultrasound. Prevalence of malignancy of the nodules was higher in men(33.3%) than in women(29.4%) although it is not statistically significant. It is known that thyroid nodule prevalence in women is much higher than in men. But this study shows the men's prevalence rate was not too low compared with women, and the men showed a rather higher malignancy rate in nodules than women. It is considered that the role of thyroid ultrasound is both important in men and women.

A Study of Structural Changes in the Seoul Metropolitan Area's Economy Since the 1990's : A Decomposition Analysis of Labor Productivity (1990년대 이후 수도권 경제의 구조적 변화에 관한 연구 : 노동생산성의 요소분해를 중심으로)

  • Jeong, Jun-Ho
    • Journal of the Korean association of regional geographers
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    • v.11 no.1
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    • pp.83-100
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    • 2005
  • The Seoul Metropolitan Area's economy has undergone structural changes since the 1990s. With recent structural changes in the Korean economy in mind, this paper employs a decomposition analysis of Gross Regional Domestic Product per head and labor productivity to examine how the region's economic performance has changed relative to that of Korea since the 1900s. There are some findings. First, a strong cumulative causation process, derived from industrial linkages and agglomeration effects, has oocurred in the Seoul Metropolitan Area, widening economic disparities between the Seoul Metropolitan Area and the other regions especially since the Korean financial crisis in 1997 mainly due to Gyeonggi province's overwhelming cumulative GRDP growth relative to the national average. Second, the Seoul Metropolitan Area has begun w display good economic performance in terms of labour productivity relative w the national average since the late 1990s, with the region's industrial upgrading being implemented. Finally, manufacturing, financial intermediation and communications have made sensitive contributions to relative Seoul Metropolitan Area's labor productivity growth.

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Five-stage Anger Model Approach to Narrative and Protagonist's Revolt Action Mechanism in the Movie, "The Man Standing Next" ('분노의 5단계 모델'관점의 영화 <남산의 부장들> 서사와 주인공의 거사 결행 기제)

  • Kim, Jeong-Seob
    • Journal of Korea Entertainment Industry Association
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    • v.14 no.3
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    • pp.285-294
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    • 2020
  • "The Man Standing Next" was a 'anger-character movie' that shows a fierce psychological game between the characters. Inspired by this point, it was analyzed the narrative structure of this film based on scene unit applying the 'Five-stage Anger Model' formulated by Lakoff and Kövecses and others. The results showed that the causality and feasibility of the protagonist's anger behavior were highly reflected above the model. In particular, among the five steps, the film-maker spent the longest time on 'anger control' justifying the hero's motivation for punishment or retaliation, while giving the shortest time to 'loss of control' to maximize the urgentness of the punitive actions. The detonator causing his anger at each stage was disposed two to six times each stage with neglect, contempt, arrogance, ostentation, mockery, unauthorized intervention, etc. Sneering of "Chief Security Officer" and insulting of "The President" make the protagonist feel the scorn of a terrible friend-murderer each functioned as a "rage trigger." In conclusion, the film follows the above sophisticated model in its narrative structure. Though it was a political drama that sets up a lot of anger scheme caused from public reasons, it reflects ordinary people's routine anger, which corresponds to 24 percent of the list of Nobaco's Provocation Inventory (PI). The producers elaborately reflected the anger procedure theory and balanced the public and private drivers of rage. It was considered to be derived from the intention to enhance communication with the audience increasing their understanding and aspiration for political movie that are usually heavy and unfamiliar.

A Study on 2-Degree-of-Freedom Controller Design of Magnetic Levitation System by $H_{\infty}$ Control ($H_{\infty}$ 제어기법에 의한 자기부상계의 2자유도 제어기 설계에 관한 연구)

  • 김창화;양주호;문덕홍
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1995.10a
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    • pp.261-266
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    • 1995
  • 본 연구에서는 자기부상시스템에 대해 흡인식 자기부상방식을 채택하고 쇠구슬에 대한 운동을 상하 1자유도로 가정하여 운동방정식을 세운다. 이때 전자석이 자기 부상력은 전자석에 흐르는 전류와 인덕턴스의 함수라 가정하고, 모델의 불확실성은 자기부상계의 운동 방정식으로부터 선형화 할 때 발생하는 오차 및 파라미터 변동으로 생각한다. 또한 모델의 불확실성이 존재하더라도 정상편차 없이 부상하는 서보제어계를 설계한다. 그런데 저자등은 강인성 문제 및 정상편차 없는 것에 역점을 두어 H$_{\infty}$ 제어이론에 기초한 1형 로바스트 서보 제어기를 구하여 자기부상 시스템의 안정화 제어계로써 적용한 적이 있다. 이때 중심해 이외의 해를 이용하여 설계한 서보 제어계는 자기부상계의 과도상태시에 일어나는 오버슈트를 줄일 수 없었다. 따라서 시스템 내부 안정화를 위하여 H$_{\infty}$ 제어이론에 의해 설계된 피드백(feedback) 제어기와 물체가 부상할 때 오버슈트를 줄이고 제어량이 목표치에 잘 추종하기 위해 설계된 피드 포워드(feed forward) 제어기로써 2자유도를 갖는 제어계를 설계한다. 이렇게 설계한 2자유도 제어계를 가지고 모의 응답실험과 본 연구자들이 만든 자기부상 시스템의 실험결과를 비교함으로써 설계된 제어기의 타당성을 조사한다.

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A Case of Brain Abscess due to Parvimonas micra in a Healthy Child without Dental Disease (특이 과거력이 없는 소아에서 발생한 Parvimonas micra 뇌농양 1예)

  • Lee, Shin Young;Roh, Tae Hoon;Jung, Hyun Joo
    • Pediatric Infection and Vaccine
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    • v.27 no.2
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    • pp.127-133
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    • 2020
  • Parvimonas micra is a non-spore-forming anaerobic gram-positive coccus and a known commensal of the skin, gums, vagina, and gastrointestinal tract. It is rarely associated with severe infections, which typically follow invasive procedures such as dental treatment. We describe a case of a brain abscess caused by P. micra in an immunocompetent 11-year-old boy without periodontal disease. He presented with a 7-day history of headaches and vomiting, and complained of diplopia that began on the day of presentation. He did not have any recent dental treatment or specific past medical history. A brain abscess in the left frontoparietal lobe was noted on brain magnetic resonance imaging. P. micra was cultured from brain abscess aspirate. He was successfully treated with surgical drainage and combined antibiotic therapy with ceftriaxone and metronidazole for 6 weeks.

A Case of Septic Arthritis due to Streptococcus intermedius in a Healthy Child (특이 과거력이 없는 소아에서 발생한 Streptococcus intermedius 화농 관절염 1예)

  • Soo Min Yong;Tae Hun Kim;Hyun Joo Jung
    • Pediatric Infection and Vaccine
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    • v.29 no.3
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    • pp.173-178
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    • 2022
  • Streptococcus intermedius is a small, non-motile, Gram-positive, non-sporeforming, and aerotolerant anaerobic coccus. It is a part of the normal microflora in the oral cavity and upper respiratory, gastrointestinal and female urogenital tracts. It is an opportunistic pathogen that causes serious infections in patients with immunocompromised states or cardiac diseases as a result of trauma or invasive procedures. We describe a case of septic arthritis of the hip caused by S. intermedius in an immunocompetent healthy 7-year-old boy without a history of periodontal disease or invasive procedures. He had hip joint pain three weeks ago, and the fever began on the day of the visit. He had been healthy and had not undergone any invasive procedures recently. Septic arthritis of the hip was indicated in the magnetic resonance imaging of the hip. S. intermedius was identified in the hip joint fluid aspiration and blood culture. He was successfully treated with surgical intervention and antibiotic therapy with ceftriaxone followed by amoxicillin for five weeks.

Epidural Abscess Caused by Eikenella corrodens in a Previously Healthy Child

  • Kim, Ye Kyung;Han, Mi Seon;Yang, Song I;Yun, Ki Wook;Han, Doo Hee;Kim, Jae Yoon;Choi, Eun Hwa
    • Pediatric Infection and Vaccine
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    • v.26 no.2
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    • pp.112-117
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    • 2019
  • Eikenella corrodens rarely causes invasive head and neck infections in immunocompetent children. We report a case of epidural abscess caused by E. corrodens in a previously healthy 13-year-old boy who presented with fever, headache, and vomiting. On physical examination upon admission, there was no neck stiffness, but discharge from the right ear was observed. Brain magnetic resonance imaging (MRI) revealed approximately 4.5-cm-sized epidural empyema on the right temporal lobe as well as bilateral ethmoid and sphenoid sinusitis, right mastoiditis, and right otitis media. During treatment with vancomycin and cefotaxime, purulent ear discharge aggravated, and on follow-up brain MRI, the empyema size increased to $5.6{\times}3.4cm$ with interval development of an abscess at the right sphenoid sinus. Burr hole trephination was performed, and foul-smelling pus was aspirated from the epidural abscess near the right temporal lobe. Pus culture yielded E. corrodens. Endoscopic sphenoidotomy was also performed with massive pus drainage, and the same organism was grown. The patient was treated with intravenous cefotaxime for 3 weeks and recovered well with no other complications. Therefore, E. corrodens can cause serious complications in children with untreated sinusitis.

Defining boundaries of urban centers and measuring the impact for diagnosing urban spatial structure (도시 공간구조 진단을 위한 도시 중심지의 경계 설정 및 영향력 측정에 관한 연구)

  • Ho-Yong Kim;Jisook Kim
    • Journal of the Korean Association of Geographic Information Studies
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    • v.27 no.1
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    • pp.52-66
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    • 2024
  • The purpose of this study is to identify the spatial system and characteristics of the urban center by deriving the boundaries of the urban center set in the urban basic plan for Busan Metropolitan City and diagnosing the role and status of the center. To this end, four indicators representing the characteristics of the center were selected through a review of previous studies, and the boundaries of the center were derived using spatial statistical techniques with strengths in geographical boundary analysis. Then, using the indicators of center characteristics and population potential functions, we diagnosed the influence and potential of each center in the spatial structure of Busan Metropolitan City. The analysis showed that the scale of the centers varies greatly, and the unutilized areas where commercial areas are not activated and the expansion areas that spread beyond commercial areas to residential and industrial areas are different for each urban center. The results of the potential measurement, which indicates the attractiveness of the center, also showed areas with strong and weak population potential. Therefore, systematic management and strategies based on the hierarchical characteristics and influence measurement results are needed to strengthen the function of urban centers. The results analyzed in this study can be used as a resource for responding to various urban planning needs and policy changes in the future, along with station area development plans and spatial innovation zones for building a sustainable urban growth system, balanced development, and strengthening the function of centers.