• Earthquakes and Structures
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• 제11권6호
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• pp.1101-1121
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• 2016

Base isolation, one of the popular seismic protection approaches proven to be effective in practical applications, has been widely applied worldwide during the past few decades. As the techniques mature, it has been recognised that, the biggest issue faced in base isolation technique is the challenge of great base displacement demand, which leads to the potential of overturning of the structure, instability and permanent damage of the isolators. Meanwhile, drain, ventilation and regular maintenance at the base isolation level are quite difficult and rather time- and fund- consuming, especially in the highly populated areas. To address these challenges, a number of efforts have been dedicated to propose new isolation systems, including segmental building, additional storey isolation (ASI) and mid-storey isolation system, etc. However, such techniques have their own flaws, among which whipping effect is the most obvious one. Moreover, due to their inherent passive nature, all these techniques, including traditional base isolation system, show incapability to cope with the unpredictable and diverse nature of earthquakes. The solution for the aforementioned challenge is to develop an innovative vibration isolation system to realise variable structural stiffness to maximise the adaptability and controllability of the system. Recently, advances on the development of an adaptive magneto-rheological elastomer (MRE) vibration isolator has enlightened the development of adaptive base isolation systems due to its ability to alter stiffness by changing applied electrical current. In this study, an innovative semi-active storey isolation system inserting such novel MRE isolators between each floor is proposed. The stiffness of each level in the proposed isolation system can thus be changed according to characteristics of the MRE isolators. Non-dominated sorting genetic algorithm type II (NSGA-II) with dynamic crowding distance (DCD) is utilised for the optimisation of the parameters at isolation level in the system. Extensive comparative simulation studies have been conducted using 5-storey benchmark model to evaluate the performance of the proposed isolation system under different earthquake excitations. Simulation results compare the seismic responses of bare building, building with passive controlled MRE base isolation system, building with passive-controlled MRE storey isolation system and building with optimised storey isolation system.

• Asian Pacific Journal of Cancer Prevention
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• 제17권4호
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• pp.2255-2258
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• 2016

Background: Awareness about prostate cancer has increased in the community, and prostate cancer screening examinations, including prostate specific antigen (PSA) assays, are now widely available. Prior to the PSA era, up to 27% of prostate cancers were detected incidentally at the time of transurethral resection of prostate (TURP). After PSA testing became widely available, the incidence of incidentally detected carcinoma prostate in TURP specimens without prior diagnosis reduced to 5-13%. However, the incidence of incidentally detected carcinoma prostate has been reported to vary across the globe since various factors can influence the identification of this malignancy in TURP specimens. In this paper, we focus on rates of incidentally detected prostate cancer in TURP specimens in our hospital and correlate it with various parameters. Materials and Methods: This retrospective study of histopathological findings of biopsy specimens was conducted for patients undergoing TURP during a period of 5 years from April 2010. The inclusion criteria were patients diagnosed with benign prostatic hyperplasia (BPH) (digital rectal examination (DRE) not showing any abnormally hard areas and normal age adjusted PSA values). Patients with elevated PSA, abnormal DRE, documented urinary tract infection and proved adenocarcinoma prostate (CaP) were excluded from the study. The total weight of prostatectomy specimen, occurrence of carcinoma prostate in the chips, percentage of total tissue resected showing malignancy and Gleason's scores were recorded. Results: A total of 597 patients belonging to the inclusion criteria were studied. The incidence of occult CaP in the study group was 5.2 % (31/597). Out of these, 8 belonged to T1a and 23 belonged to T1b stages. The age group 70 - 79 years had the maximum incidence of occult CaP. It was observed that the clinical grading of prostate did not have a bearing on the incidence of occult CaP whereas the weight of resected specimen correlated with the incidence of CaP. The incidence of occult CaP was greater with low volume prostates (<20 g). (P=0.15). Conclusions: The rate of incidentally detected adenocarcinoma prostate in patients undergoing TURP for clinically diagnosed BPH was found to be only 5.2 % in our study which is low when compared with similar studies done elsewhere. The age of the patient and weight of the resected specimen correlated with incidence of occult prostate cancer. The clinical grading of prostate by DRE however, demonstrated no correlation.

• Journal of Korean Neurosurgical Society
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• 제56권1호
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• pp.21-27
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• 2014

Objective : Infectious spinal disease is regarded as an infection by a specific organism that affects the vertebral body, intervertebral disc and adjacent perivertebral soft tissue. Its incidence seems to be increasing as a result of larger proportion of the older patients with chronic debilitating disease, the rise of intravenous drug abuser, and the increase in spinal procedure and surgery. In Korea, studies assessing infectious spinal disease are rare and have not been addressed in recent times. The objectives of this study are to describe the epidemiology of all kind of spinal infectious disease and their clinical and microbiological characteristics as well as to assess the diagnostic methodology and the parameters related to the outcomes. Methods : A retrospective study was performed in all infectious spinal disease cases presenting from January 2005 to April 2010 to three tertiary teaching hospitals within a city of 1.5 million in Korea. Patient demographics, risk factors, clinical features, and outcomes were assessed. Risk factors entailed the presence of diabetes, chronic renal failure, liver cirrhosis, immunosuppressants, remote infection, underlying malignancy and previous spinal surgery or procedure. We comparatively analyzed the results between the groups of pyogenic and tuberculous spinal infection. SPSS version 14 statistical software was used to perform the analyses of the data. The threshold for statistical significance was established at p<0.05. Results : Ninety-two cases fulfilled the inclusion criteria and were reviewed. Overall, patients of tuberculous spinal infection (TSI) and pyogenic spinal infection (PSI) entailed 20 (21.7%) and 72 (78.3%) cases, respectively. A previous spinal surgery or procedure was the most commonly noted risk factor (39.1%), followed by diabetes (15.2%). The occurrence of both pyogenic and tuberculous spondylitis was predominant in the lumbar spine. Discs are more easily invaded in PSI. At initial presentation, white cell blood count and C-reactive protein levels were higher in PSI compared to TSI (p<0.05). Etiological agents were identified in 53.3%, and the most effective method for identification of etiological agents was tissue culture (50.0%). Staphyococcus aureus was the most commonly isolated infective agent associated with pyogenic spondylitis, followed by E. coli. Surgical treatment was performed in 31.5% of pyogenic spondylitis and in 35.0% of tuberculous spondylitis cases. Conclusion : Many previous studies in Korea usually reported that tuberculous spondylitis is the predominant infection. However, in our study, the number of pyogenic infection was 3 times greater than that of tuberculous spinal disease. Etiological agents were identified in a half of all infectious spinal disease. For better outcomes, we should try to identify the causative microorganism before antibiotic therapy and make every effort to improve the result of culture and biopsy.

• 한국수자원학회논문집
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• 제46권3호
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• pp.315-326
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• 2013

저수지 내 퇴적과정으로 의한 저수용량 감소에 대한 효율적 관리의 중요성에도 불구하고, 불확실성을 포함하는 확률론적 관점의 신뢰도 분석이론을 활용한 저수용량 감소에 관한 연구는 많지 않다. 본 연구에서는 신뢰도 분석모형의 하나인 추계학적 감마 과정(stochastic gamma process)을 이용하고 개발된 모형을 소양강댐에서 적용하여 향후 발생될 수 있는 저수용량의 감소를 불확실성 측면에서 분석하였다. 특히 불확실성을 분석하기 위하여 정보적 사전분포(informative prior distribution)를 이용한 Bayesian MCMC 기법을 사용하여 추계학적 감마 과정의 모수(parameter)를 추정하였다. 구축된 정보적 사전분포를 적용한 결과사전분포의 불확실성에 비해 사후분포의 불확실성이 상당히 감소되어져 정보적 사전분포의 효과를 확인할 수 있었으며, 소양강댐 퇴사용량의 기대수명은(expected life time)은 5%유의수준에서 119.3년부터 183.5년의 불확실성을 나타내는 것으로 분석되었다. 이와 같은 연구는 저수용량의 감소에 관한 불확실성 측면의 정보를 신뢰도 분석결과와 함께 제공할 수 있으므로, 향후 퇴적과정으로 인한 저수지의 유지관리계획을 수립함에 있어 댐관리자 등에게 효과적으로 활용될 수 있을 것으로 판단된다.

• 한국의류학회지
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• 제28권9_10호
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• pp.1273-1281
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• 2004

가격반응함수는 각 가격대별로 판매량의 변화를 추적한 함수이다. 가격에 판매량을 곱하면 판매량이 되고, 여기에 비용을 차감하면 이익이 된다. 따라서 가격반응함수는 상표나 제품의 이익을 최대로 하는 가격을 찾는 바탕이다 컨조인트분석은 고객시각에서 가격반응함수를 도출하는데 신뢰성 높은 방법으로 적극적으로 권해지고 있으나, 고려상표군을 고려하지 못한다는 단점이 지적되어 왔다 이 연구는 고려상표군을 측정할 수 있는 컨조인트분석의 한 변종으로 2단계 컨조인트분석을 개발하여 미국의 한 도시의 청바지 시장에 적용하였다. 그 결과, 고려상표군 정보를 가진 가격반응함수와 그렇지 않은 가격반응함수 간의 특정가격대별 선택확률과 가격탄력성에 차이가 발생함이 발견되었다. 고려상표군 형성이 소비자의 구매의사결정과정의 한 단계임을 고려할 때, 고려상표군 정보를 가진 가격반응함수로 소비자의 가격반응을 추적하는 것이 필요함이 이 연구를 통해 실증되었다.

• 대한후두음성언어의학회지
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• 제22권1호
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• pp.47-51
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• 2011

Background and Objectives: Vocal polyps arc one of the most frequent benign laryngeal diseases. They arc usually found at the midpoint of the vocal fold. They are mainly caused by vocal overuse. Vocal polyps arc usually removed surgically. Generally, age-related changes to speech are attributed to change in anatomy and physiology of the speech mechanism. These changes result in increased variability in the acoustic properties of speech with age. Still, not 'all studies of age-related changes in speech have taken differences between the young group and adult group after laryngeal microsurgery into account. The aim of this investigation was to compare improvement of acoustic analysis in young patients and elderly patients with vocal polyps, before and after the laryngeal microsurgery. Materials and Method: One hundred and twenty-eight patients who underwent laryngeal microsurgery for vocal polyps from 2008 through 2011 were reviewed retrospectively. 105 of the 128 patients under age 60 were classified as adult group (AG), and remaining 23 patients as elderly group (EG). The speech of AG and EG were evaluated before and after surgery for identification of differences for age group across measures of fundamental frequency (F0), Jitter, Shimmer and Maximum phonation time (MPT). Results: There were not significant differences between two groups for improvement of F0, Jitter, Shimmer, NHR, and MPT before and after surgery. The findings suggest that elderly group compares quite well with adult group in effectiveness of surgery. However, comparison between elderly group and young group (Age under 40) there was significant difference of improvement in Jitter and Shimmer. Conclusion: In general, the results of the present research showed significant improvement in vocal quality after phonosurgery of vocal polyp in both elderly and adult group. However, comparison of improvement between elderly group and young group, there were significant differences of improvement in jitter and shimmer. Therefore, in treatment planning of elderly group, we should consider age related changes of vocal cord.

• Asian-Australasian Journal of Animal Sciences
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• 제31권8호
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• pp.1119-1126
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• 2018

Objective: Present investigation was aimed to study the Single Nucleotide Variants of the luteinizing hormone beta ($LH{\beta}$) gene and to analyze their association with the semen quality (fresh and post-thawed frozen semen) and luteinizing hormone (LH) concentrations in Murrah buffalo bulls. Methods: Polymerase chain reaction-single stranded conformational polymorphism (PCR-SSCP) and Sanger sequencing method is used to study genetic variability in $LH{\beta}$ gene. LH assay was carried out using enzyme-linked immunosorbent assay method. A fixed general linear model was used to analyze association of single nucleotide polymorphism (SNP) of $LH{\beta}$ gene with semen quality in 109 and LH concentrations in 80 Murrah bulls. Results: $LH{\beta}$ gene was found to be polymorphic. Total six SNPs were identified in $LH{\beta}$ gene g C356090A, g C356113T, g A356701G, g G355869A, g G356330C, and g G356606T. Single Stranded Conformational Polymorphism variants of pattern 2 of exon 1+pattern 2 of exon 2+pattern 1 of exon 3 had highly significant (p<0.01) effect on sperm concentration (million/mL), percent mass motility, acrosome integrity and membrane integrity in fresh and frozen semen whereas significant (p<0.05) effect was observed on percent live spermatozoa. SSCP variants of pattern 2 of exon 1+pattern 2 of exon 2+pattern 1 of exon 3 had highly significant (p<0.01) effect on luteinizing hormone concentrations too. Conclusion: The observed association between SSCP variants of $LH{\beta}$ gene with semen quality parameters and LH concentrations indicated the possibilities of using $LH{\beta}$ as a candidate gene for identification of markers for semen quality traits and LH concentrations in Murrah buffaloes.

• Clinical and Experimental Reproductive Medicine
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• 제43권2호
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• pp.126-132
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• 2016

Objective: The purpose of this study was to identify useful clinical factors for the identification of patients with polycystic ovary syndrome (PCOS) who would benefit from in vitro maturation (IVM) treatment without exhibiting compromised pregnancy outcomes. Methods: A retrospective cohort study was performed of 186 consecutive patients with PCOS who underwent human chorionic gonadotropin-primed IVM treatment between March 2010 and March 2014. Only the first IVM cycle of each patient was included in this study. A retrospective case-control study was subsequently conducted to compare pregnancy outcomes between IVM and conventional in vitro fertilization (IVF) cycles. Results: Through logistic regression analyses, we arrived at the novel finding that serum $anti-M{\ddot{u}}llerian$ hormone (AMH) levels and the number of fertilized oocytes in IVM were independent predictive factors for live birth with unstandardized coefficients of 0.078 (95% confidence interval [CI], 1.005-1.164; p=0.037) and 0.113 (95% CI, 1.038-1.208; p=0.003), respectively. Furthermore, these two parameters were able to discriminate patients who experienced live births from non-pregnant IVM patients using cut-off levels of 8.5 ng/mL and five fertilized oocytes, respectively. A subsequent retrospective case-control study of patients with PCOS who had serum AMH levels ${\geq}8.5ng/mL$ showed that IVM had pregnancy outcomes comparable to conventional IVF, and that no cases of ovarian hyperstimulation syndrome were observed. Conclusion: Serum AMH levels are a useful factor for predicting pregnancy outcomes in PCOS patients before the beginning of an IVM cycle. IVM may be an alternative to conventional IVF for PCOS patients if the patients are properly selected according to predictive factors such as serum AMH levels.

• 한국동물학회지
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• 제39권4호
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• pp.437-446
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• 1996

한국산 도롱뇽(Hynobius leechii)의 암수의 신체적 특성 및 구애,싸움 행동에 대한 연구를 수행하였다. 몸의 길이, 코부터 총배설까지의 길이, 몸의 길이에 대한 코부터 총 배설강까지 길이의 비에 있어서 암컷이 수컷보다 더 길었으며, 수컷들은 몸의 길이, 코부터 총배설까지의 길이, 머리의 넓이, 꼬리부터 총배설까지의 길이, 꼬리의 넓이의 5개 요소에 있어서 모든 요소들이 서로 유의미한 상관을 보인 반면, 암컷에 있어서는 꼬리의 넓이를 제외한 모든 요소에서 의미 있는 상관을 보였다. 체외수정을 하는 한국산 도롱뇽의 성적인 행동은 암컷을 확인하는 단계,암컷을 유인하는 단계, 그리고 수정 단계로 구성되어진다. 안컷을 확인하는 단계는 암컷에게로 접근 행동 및 서로 코를 맞대는 행동으로 구성되며, 유인단계에서는 턱부비기, 꼬리치기, 냄새맡기, 파기의 네 가지의 과시 행동이 나타났다. 수정의 과정은 포집, 암컷으로부터 알주머니의 분리, 알의 수정, 수정 후 과시행동으로 구성되었다. 싸움 행동은 간단한 편으로, 공격하는 개체는 상대편의 위턱이나 뒷다리 부근을 주로 물었으며, 문 상태에서 자신의 머리를 2-3회 흔드는 행동을 보였다. 대부분의 경우에 있어서 개체의 크기에 상관없이 공격을 당한 개체는 공격한 개체로부터 재 빨리 회피를 하였으며, 승리를 한 개체는 빠른 꼬리치기 과시 행동을 보였다.

• 대한교통학회지
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• 제26권4호
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• pp.251-264
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• 2008

정확하고 신뢰성 있는 실시간 교통자료의 수집은 다양한 교통운영관리 전략의 구현 및 교통정보제공을 위한 필수요소이다. 본 연구에서는 보다 seamless한 고급 교통정보가공을 위해 차량 간 무선통신기술(Vehicle-To-Vehicle Communication; V2V)을 활용한 새로운 교통정보수집체계를 제안하였다. GPS를 이용하여 개별차량의 주행궤적을 추출하고 V2V를 이용한 교통정보수집 방안을 제시하였다. 본 연구에서 제안한 교통정보수집체계의 기술적 요구사항분석을 위해 몬테카를로 시뮬레이션 기반의 평가체계를 개발하였다. 미시적 교통시뮬레이터 AIMSUN으로부터 개별차량의 주행궤적을 추출하고, 이를 이용한 구간통행시간 산출기법을 몬테카를로 시뮬레이션 기반 평가체계에 결합하여 기술적 요구사항을 도출하였다. 구간통행시간 정확도에 영향을 미치는 요인으로서 V2V 및 개별차량 주행궤적 추출이 가능한 equipped vehicle의 market penetration rate, V2V 통신반경, 통행시간 산출주기를 분석하였다. 또한, 제안된 시스템의 기술적 타당성 확인을 위해 prototypical implementation을 수행하였다. 본 연구의 결과물은 보다 seamless하고 정확한 교통정보가공을 위한 차세대 수집시스템 개발 및 구현을 위한 유용한 기초자료로 활용될 것으로 기대된다.