• Title/Summary/Keyword: Transient period

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Complications in Total Thyroidectomy (갑상선 전절제의 합병증)

  • Han Gwang-Hee;Chin Hyung-Min;Park Woo-Bae;Kim Jun-Gi;Chun Chung-Soo
    • Korean Journal of Head & Neck Oncology
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    • v.10 no.2
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    • pp.106-111
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    • 1994
  • During a 9-year period(March 1985 to February 1994), 111 consecutive total thyroidectomies and modified or radical neck dissections were performed at 81. Vincent Hospital, Catholic University Medical College, for benign and malignant disease. There were three permanent complications, persistent hypoparathyroidism, in total thyroidectomies. Overall complications were observed 20(62.5%) in benign diseases, 47(59.5%) in malignancy. In benign and malignant thyroid diseases. the complications were transient hypoparathyroidisms (28.8%), transient hoarsenesses(21.6%), wound infections (3.6%), bleedings(3.6%), and permanent hypoparathyroidisms(2.7%). Our experience suggests that the morbidity of total thyroidectomy relates primarily to the extracapsular extension, necessitating en bloc exision accompanied by additional lymph node dissection. The low incidence of permanent complications in thyroid disease suggests the feasibility of total thyroidectomy as the operation of choice when surgeons are familiar with the technique and indications.

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Power Quality Analysis of Jeju Power System during HVDC Overhaul using PSCAD/EMTDC (PSCAD/EMTDC에 의한 직류연계선 오버홀시 제주계통의 전력품질 분석)

  • Kang, Bo-Seung;Kim, Jae-Hong;Kim, Eel-Hwan;Kim, Se-Ho;Oh, Seong-Bo;Song, Ki-Heouk
    • Proceedings of the KIPE Conference
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    • 2008.06a
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    • pp.82-84
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    • 2008
  • This paper presents the modeling and power quality analysis of Jeju island power system connected with wind farm, and thermal power plant. It is for indicating the influence of wind farm operation in steady and transient state in Jeju island power system during the HVDC system overhaul period. For the computer simulation, three kinds of main item are modeled, which are 67[MW] wind farm, thermal power plant and Jeju power load. To analyze the influence of the wind power generation to the Jeju power system, two kinds of simulations are carried out by using the PSCAD/EMTDC program. One is the steady state operation under the variable speed wind, and the other is the transient state operation when all of wind farms in Jeju island are disconnected from the Jeju power grid instantaneously on the rated power output. With the comparison of these results, it is useful for analyzing the power quality of Jeju power system versus wind power generation.

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Sjögren Syndrome after Radioiodine Therapy in Thyroid Cancer Patients

  • Lee, Hee Jin;Kim, Jae-Jeong;Kim, Young-Gun;Ahn, Hyung-Joon;Choi, Jong-Hoon;Kwon, Jeong-Seung
    • Journal of Oral Medicine and Pain
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    • v.43 no.3
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    • pp.84-86
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    • 2018
  • Salivary and lacrimal gland dysfunction is relatively frequent after radioiodine therapy. In most cases this is a transient side effect, but in some patients it may persist for a long period or appear late. Radioiodine ($^{131}I$) therapy is often administered to patients following total thyroidectomy to treat well-differentiated follicular cell-derived thyroid cancer. In addition to the thyroid, $^{131}I$ accumulates in the salivary glands, giving rise to transient or permanent salivary gland damage. Salivary gland dysfunction following radioiodine therapy can be caused by radiation damage. But, it also may be associated with $Sj{\ddot{o}}gren$ syndrome (SS) developed after radioiodine therapy. It would be recommended that the evaluation for SS including anti-SSA/Ro and anti-SSB/La should be considered before and after radioiodine therapy.

Digital Redesign using the Discrete Grammian Method (연속제어기의 GSHF(Generalized Sampled-data Hold Function)을 이용한 디지탈 재설계시의 이산적 GRAMMIAN 행렬의 사용)

  • Chung, Chi-B.;Chung, Tae-S.;Yang, Won-Y.
    • Proceedings of the KIEE Conference
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    • 1993.07a
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    • pp.306-309
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    • 1993
  • Digital redesign techniques are to derive a digital controller fred the existing continuous controller and its plant so that the performance of the digitally controlled system is matched as closely as possible to that of the original continuous system at the sampling instants. Recently a new digital redesign technique, was developed to use the generalized sampled-data hold function(GSHF) based on the the grammian matrix. With this new technique the digitally redesigned system showed several good features compared with any existing technique in terms of the state match at the sampling instants, the large sampling period, and the transient reponses. This paper concerns a further improvement of the new digital redesign technique by employing the discrete grammian matrix instead of the continuous grammian matrix in defining GSHF. With this modification, it was observed by simulation that the transient response of the modified digital system shows far better performance than the digital system based on the continuous grammian matrix.

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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
    • The Journal of Engineering Geology
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    • v.24 no.1
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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.

Strategy for the Seamless Mode Transfer of an Inverter in a Master-Slave Control Independent Microgrid

  • Wang, Yi;Jiang, Hanhong;Xing, Pengxiang
    • Journal of Power Electronics
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    • v.18 no.1
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    • pp.251-265
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    • 2018
  • To enable a master-slave control independent microgrid system (MSCIMGS) to supply electricity continuously, the microgrid inverter should perform mode transfer between grid-connected and islanding operations. Transient oscillations should be reduced during transfer to effectively conduct a seamless mode transfer. This study uses a typical MSCIMGS as an example and improves the mode transfer strategy in three aspects: (1) adopts a status-tracking algorithm to improve the switching strategy of the outer loop, (2) uses the voltage magnitude and phase pre-synchronization algorithm to reduce transient shock at the time of grid connection, and (3) applies the hybrid-sensitivity $H_{\infty}$ robust controller instead of the current inner loop to improve the robustness of the controller. Simulations and experiments show that the proposed strategy is more practical than the traditional proportional-derivative control mode transfer and effective in reducing voltage and current oscillations during the transfer period.

Diagnostic Hierarchy of Tic Disorders in Real-World Clinical Practice

  • Yeeji Sung;Soon-Beom Hong
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.34 no.4
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    • pp.236-241
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    • 2023
  • Objectives: According to the 10th revision of the International Classification of Diseases, the main categories of tic disorders (F95.0, F95.1, and F95.2) follow a diagnostic hierarchy based on the duration and diversity of tic symptoms. The present study investigated the use of this diagnostic hierarchy in real-world clinical practice. Methods: Based on the National Health Insurance Service-National Health Information Database, the diagnosis of transient tic disorder (F95.0) made after a diagnosis of chronic motor or vocal tic disorder (F95.1) or Tourette's syndrome (F95.2) and diagnosis of chronic motor or vocal tic disorder (F95.1) made after a diagnosis of Tourette's syndrome (F95.2) were referred to as type A errors. The diagnosis of transient tic disorder (F95.0) repeated after a period of >12 months was referred to as type B error. Demographic and clinical differences according to the diagnostic error types were analyzed using analysis of variance, Student's t-tests, and chi-squared tests. Results: Most participants (96.5%) were without errors in the diagnosis of tic disorders. Higher proportions of males (p=0.005) and antipsychotic prescriptions (p<0.001) were observed in patients with type A or B diagnostic errors. A higher proportion of health insurance holders was observed among those with type A errors (p=0.027). Conclusion: Errors were absent in majority of the tic diagnoses in real-world clinical practice in terms of the diagnostic hierarchy.

Effect of Rice stripe virus NS3 on Transient Gene Expression and Transgene Co-Silencing

  • Sohn, Seong-Han;Huh, Sun-Mi;Kim, Kook-Hyung;Park, Jin-Woo;Lomonossoff, George
    • The Plant Pathology Journal
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    • v.27 no.4
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    • pp.310-314
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    • 2011
  • Nonstructural protein 3 (NS3) encoded by RNA3 of Rice stripe virus (RSV), known to be a suppressor of gene silencing, was cloned and sequenced. The cloned NS3 gene is composed of 636 nucleotides encoding 211 deduced amino acids, and showed a high degree of similarity with the equivalent genes isolated from Korea, Japan and China. The NS3 gene promoted the enhancement of transient gene expression and suppressed transgene co-silencing. In the transient GFP expression via agroinfiltration, GFP expression was dramatically enhanced in terms of both protein yield and expression period in the presence of NS3. The highest accumulation of GFP protein reached to 6.8% of total soluble proteins, which corresponded to a two-fold increase compared to that obtained in the absence of NS3. In addition, NS3 significantly suppressed the initiation of GFP co-silencing induced by the additive GFP infiltration in GFP-transgenic Nicotiana benthamiana. The NS3 gene was also found to be a stronger suppressor than Cucumber mosaic virus 2b. These observations are believed to be derived from the strong suppressive effect of NS3 on gene silencing, and indicate that NS3 could be used as an effective enhancer for the rapid production of foreign proteins in plants.

Urgent Recanalization with Stenting for Severe Intracranial Atherosclerosis after Transient Ischemic Attack or Minor Stroke

  • Park, Tae-Sik;Choi, Beom-Jin;Lee, Tae-Hong;Song, Joon-Suk;Lee, Dong-Youl;Sung, Sang-Min
    • Journal of Korean Neurosurgical Society
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    • v.50 no.4
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    • pp.322-326
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    • 2011
  • Objective : Stenting of symptomatic intracranial stenosis has recently become an alternative treatment modality. However, urgent intracranial stenting in patients with intracranial stenosis following a transient ischemic attack (TIA) or minor stroke is open to dispute. We sought to assess the feasibility, safety, and effectiveness of urgent intracranial stenting for severe stenosis (>70%) in TIA or minor stroke patients. Methods : Between June 2009 and October 2010, stent-assisted angioplasty by using a balloon-expandable coronary stent for intracranial severe stenosis (>70%) was performed in 7 patients after TIA and 5 patients after minor stroke (14 stenotic lesions). Technical success rates, complications, angiographic findings, and clinical outcomes were retrospectively analyzed. Results : Stenting was successful in all 12 patients. The mean time from symptom onset to stenting was 2.1 days (1-8 days). Post-procedural angiography showed restoration to a normal luminal diameter in all patients. In-stent thrombosis occurred in one patient (n=1, 8.3%), and was lysed with abciximab. No device-related complications, such as perforations or dissections at the target arteries or intracranial hemorrhaging, occurred in any patient. The mortality rate was 0%. No patient had an ischemic event over the mean follow-up period of 12.5 months (range, 7-21 months), and follow-up angiography (n=7) revealed no significant in-stent restenosis (>50%). Conclusion : Urgent recanalization with stenting is feasible, safe, and effective in patients with TIA or acute minor stroke with intracranial stenosis of ${\geq}$ 70%.

Investigation of Transition Types of HPV DNA Test Results over Time in Korean Women

  • Ko, Kiwoong;Kwon, Min-Jung;Woo, Hee-Yeon;Park, Hyosoon
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.8
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    • pp.3167-3172
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    • 2015
  • Background: Understanding the history of human papilloma virus (HPV) infection is important for interpretation of a positive HPV DNA screening test, future work-up and treatment. We investigated the transition of HPV DNA test results in Korean women, and analyzed the association of cytology result with transition type. Materials and Methods: We retrospectively reviewed annual HPV DNA test results for 5,274 subjects between January 2005 and December 2012. Each subject had a minimum of five annual tests over the eight-year period. Based on the pattern of results, the transition type for each subject was assigned to one of the following: negative, persistent, latent, transient, and unclassifiable. Associations of cytology results with the HPV DNA transition types, number of positive results, and the durations of positive results were also analyzed. Results: The proportion of abnormal cytology findings decreased in the following order of transition patterns: persistent, latent, transient, and negative. Among transient patterns, a duration of three years or more significantly correlated with cytology results of non-high grade squamous intraepithelial lesion (HSIL; p<0.001). In the persistent group, duration of five years or more correlated with both non-HSIL and HSIL (p<0.001). Latent group showed no correlation with duration. Irrespective of patterns, having five or more positive results was significantly associated with HSIL (p<0.001). Conclusions: Our findings may contribute to better understanding of HPV infection, interpretation of HPV DNA screening results, and prediction of prognosis according to transition type.