• Communications for Statistical Applications and Methods
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• 제10권2호
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• pp.277-289
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• 2003

We propose modified exact inferential methods in logistic regression model. Exact conditional distribution in logistic regression model is often highly discrete, and ordinary exact inference in logistic regression is conservative, because of the discreteness of the distribution. For the exact inference in logistic regression model we utilize the modified P-value. The modified P-value can not exceed the ordinary P-value, so the test of size $\alpha$ based on the modified P-value is less conservative. The modified exact confidence interval maintains at least a fixed confidence level but tends to be much narrower. The approach inverts results of a test with a modified P-value utilizing the test statistic and table probabilities in logistic regression model.

• 한국전산구조공학회논문집
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• 제19권4호
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• pp.429-440
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• 2006

이 연구의 목적은 두 가지로 대별할 수 있다. 첫째는, 베리오그램 모델링에 기초를 둔 정규크리깅 보간법의 p-적응적 유한요소법으로의 적용성이다. 둘째는, 수정된 초수렴 팻취복구 기법을 사용한 사후오차평가기와 연계된 계층적 p-체눈 세분화의 적응적 유한요소 과정을 제시하는 것이다. 가중치를 부여한 보간기법중의 하나인 정규크리깅 방법은 가우스 적분점에서의 응력데이타로 부터 소위 준정해를 얻는데 적용된다. 가중치를 동일하게 가정하는 종래의 보간기법과는 달리 실험적 및 이론적 베리오그램을 작성한 후 보간을 위한 가중치를 결정하게 된다. 한편, 적응적 p-체눈 세분화는 해석영역의 각 체눈에서 p-차수를 만족할만한 정확도를 얻을 수 있도록 프로그램내에서 자동으로 사후오차평가를 통해 불균등 또는 선택적으로 증가시킨다. 수정된 초수렴 팻취복구기법을 검증하기 위해 극한치를 사용한 새로운 오차평가기가 제안된다. 제안된 알고리즘의 정당성은 선형탄성파괴역학의 대표적 문제들인 중앙균열판, 일변균열 및 양변균열 해석을 통해 테스트되었다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2003년도 봄 학술발표회 논문집
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• pp.288-295
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• 2003

An adaptive procedure in finite element analysis is presented by p-refinement of meshes in conjunction with a posteriori error estimator that is based on the recovery technique. In case of the recovery technique, the SPR(superconvergent patch recovery) approach has been modified for p-adaptive mesh refinement. The strategy of finding a nearly optimal distribution of polynomial degrees on a fixed finite element mesh is discussed such that a particular element has to be refined automatically to obtain an acceptable level of accuracy by increasing p-levels non-uniformly. To verify the proposed algorithm, the limit value approach is proposed which utilizes the exact strain energy computed from the extrapolation equation. A new pre-processor is developed for the p-version finite element program in which the vector graphic editor is used for the automatic generation of node connection and coordinate by halfedge solid data structure according to uniform or nonuniform p-distribution. The general 2-D algorithm is also developed to generate face modes and internal modes in accordance with different mesh types. The quality of the error estimator is investigated with the help of two mumerical examples. The results show that the sequences of p-distributions obtained by the proposed error indicator closely follow the optimal trajectory.

• 한국인터넷방송통신학회논문지
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• 제15권1호
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• pp.207-215
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• 2015

본 논문은 지금까지 NP-완전 문제로 다항시간 알고리즘이 존재하지 않는 스도쿠 문제의 해를 다항시간으로 구하는 알고리즘을 제안하였다. 제안된 알고리즘은 숫자가 많이 들어 있는 블록 내림차순으로 수행한다. 각 블록에서 빈칸들을 대상으로 행에 들어 갈 수 있는 숫자와 열에 들어갈 수 있는 숫자를 결정한다. 행과 열의 교집합을 구하면 해당 빈칸에 들어갈 수 있는 숫자가 결정된다. 이들 숫자를 대상으로 각 빈칸에 들어 갈 수 있는 숫자를 배정하는 방법을 적용하였다. 제안된 알고리즘은 전통적인 $9{\times}9$ 스도쿠에 적용 결과 블록의 개수인 9회만을 수행하여 해를 구하는데 성공하였다. 또한, 변형 스도쿠인 Jigsaw 스도쿠 (9개 블록)와 Hypersudoku (13개 블록)에 적용 결과 Jigsaw 스도쿠는 9회, Hypersudoku는 13회 수행으로 해를 구하는데 성공하였다. 결국, 제안된 알고리즘은 스도쿠 문제가 P-문제임을 증명하였다.

• Advances in pediatric surgery
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• 제7권1호
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• pp.1-6
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• 2001

The aims of this study were to evaluate the prognostic predictabilities of the risk classifications (Waterston, Montreal, and Spitz), preoperative treatment of pneumonia and the length of esophageal gap in esophageal atresia. Twenty-five cases of esophageal atresia were reviewed retrospectively. The data was analyzed with Likelihood ratio test for trend and Fisher's exact test. Survival rates were 100.0 % in group A and B, and 60.0 % in group C according to Waters ton classification (p=0.027). By Montreal classification, 95.7 % in group I and 50.0 % in group II (p=0.086). By Spitz classification, 95.5 % in group I and 66.7% in group II (p=0.159). The survival rate was 85.7 % in the patients with pneumonia preoperatively treated and 94.4% in the patients without pneumonia. The difference was not significant (p=0.490). Survival rate in the patients with long gap (${\geq}$3cm) was 50.0 % and 100.0 % in patients with short gap (<3cm) with significant difference (p=0.020). The Waterston classification could be modified into two groups because the prognosis of both group A and B were the same. Preoperative pneumonia does not seem to be a risk factor. The length of the esophageal gap showed prognostic value.

• 셀메드
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• 제12권1호
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• pp.3.1-3.7
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• 2022

Background & Objectives: Polycystic ovarian syndrome (PCOS) is one of the commonest endocrine abnormality in women of reproductive age affecting from 4% - 21% of the reproductive women and is characterized by chronic anovulation and hyperandrogenism. The aim of the study was to evaluate the effect of majoon idraare haiz in menstrual regulation and morphological changes in ovaries in poly cystic ovarian syndrome. Methods: A Pilot study was carried out in the department of Ilmul qabalat wa amraze niswan, National institute of unani medicine, hospital, Bengaluru. Fifteen Patients of PCOS aged 18-35 diagnosed using Rotterdam criteria were included in the study. Patients with insulin sensitizing treatment within 3 months, hormonal treatment and those with h/o diabetes mellitus, hypertension, pregnant and lactating women were excluded.Majoon idraare haiz was administered orally at a dose of 10 g with 20 ml arqbed mushk once daily from fifth day of cycle for 21 days for three consecutive cycles. Primary outcome measure was menstrual regularity while changes in USG pelvis(normal ovarian morphology) was considered as secondary outcome measure. In addition, duration of flow and changes in basal metabolic index (BMI), modified Ferriman Gallwey (mFG) score, acanthosis nigricanswere observed. Data were analyzed using, ANOVA, paired student 't' test, fisher exact test. Results: Changes in duration of cycle, duration and amount of flow was achieved in 93.3% patients with p<0.0001 and 46.6% patients showed normal findings on pelvic ultrasonography with p=0.006. In addition, significant changes were also observed in BMI, hirsutism and acanthosis nigricans with p value of 0.0001, p=0.003 and p=0.009 respectively Conclusion: Majoonidraare haiz can be used as an effective alternative in management of PCOS patients. It has significant effect on menstrual regulation and changes in polycystic ovarian morphology to normal.

• Korean Journal of Radiology
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• 제24권10호
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• pp.1028-1037
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• 2023

Objective: To evaluate the computed tomography (CT) features for diagnosing metastatic cervical lymph nodes (LNs) in patients with differentiated thyroid cancer (DTC) and validate the CT-based risk stratification system suggested by the Korean Thyroid Imaging Reporting and Data System (K-TIRADS) guidelines. Materials and Methods: A total of 463 LNs from 399 patients with DTC who underwent preoperative CT staging and ultrasound-guided fine-needle aspiration were included. The following CT features for each LN were evaluated: absence of hilum, cystic changes, calcification, strong enhancement, and heterogeneous enhancement. Multivariable logistic regression analysis was performed to identify independent CT features associated with metastatic LNs, and their diagnostic performances were evaluated. LNs were classified into probably benign, indeterminate, and suspicious categories according to the K-TIRADS and the modified LN classification proposed in our study. The diagnostic performance of both classification systems was compared using the exact McNemar and Kosinski tests. Results: The absence of hilum (odds ratio [OR], 4.859; 95% confidence interval [CI], 1.593-14.823; P = 0.005), strong enhancement (OR, 28.755; 95% CI, 12.719-65.007; P < 0.001), and cystic changes (OR, 46.157; 95% CI, 5.07-420.234; P = 0.001) were independently associated with metastatic LNs. All LNs showing calcification were diagnosed as metastases. Heterogeneous enhancement did not show a significant independent association with metastatic LNs. Strong enhancement, calcification, and cystic changes showed moderate to high specificity (70.1%-100%) and positive predictive value (PPV) (91.8%-100%). The absence of the hilum showed high sensitivity (97.8%) but low specificity (34.0%). The modified LN classification, which excluded heterogeneous enhancement from the K-TIRADS, demonstrated higher specificity (70.1% vs. 62.9%, P = 0.016) and PPV (92.5% vs. 90.9%, P = 0.011) than the K-TIRADS. Conclusion: Excluding heterogeneous enhancement as a suspicious feature resulted in a higher specificity and PPV for diagnosing metastatic LNs than the K-TIRADS. Our research results may provide a basis for revising the LN classification in future guidelines.

• 대한족부족관절학회지
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• 제27권2호
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• pp.49-54
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• 2023

Purpose: The present study examined the effectiveness of the preoperative ischemia-modified albumin (IMA) levels in predicting the healing period of amputation wounds in patients with diabetes mellitus following a non-traumatic below-knee amputation (BKA). Materials and Methods: This study enrolled 41 diabetic foot ulcer patients who underwent BKA at the authors' hospital diabetic foot center from April 2016 to April 2022. Among the 41 patients, 29 (70.7%) were male and 12 (29.3%) were female. Their mean age was 64.54±11.38 years (41~81 years). The mean follow-up period was 19.48±5.56 weeks (14~48 weeks) after BKA. The patients were divided into two groups (high IMA group and normal IMA group), which evaluated the healing period, wound dehiscence, and revision operation rate using a Fisher's exact test and Mann-Whitney U test. Three orthopedic surgeons performed stump wound evaluation, and they were evaluated as healing when all sutures were fused without oozing. Results: Thirty patients (73.2%) (group A) showed a high level of IMA (median: 91.2 U/mL), and 11 (26.8%) patients (group B) showed a normal range of IMA (median: 82.7 U/mL). In group A, the median period for wound healing took 1.4 weeks longer, which was significant (p=0.001). No statistical relationship was observed between wound dehiscence, revision operation rate, and IMA value. There was no correlation between the other risk factors (estimated glomerular filtration rate, HbA1c) and the wound healing period. Conclusion: Although there was a limitation in using IMA as the sole factor to predict the healing period of amputation wounds in patients after BKA, this study revealed a significant positive correlation between IMA and the period of stump healing after BKA. Therefore, the preoperative IMA levels may help predict the period of stump healing after BKA.

• 한국동물위생학회지
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• 제31권4호
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• pp.497-504
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• 2008

A cross-sectional study was undertaken to report prevalence and to identify risk factors of subclinical mastitis of dairy cattle in Sylhet district of Bangladesh. Among 325 dairy farms of the district 12 farms(3.7%) were selected conveniently for this study. All the dairy cows of the 12 farms were selected for sample collection. Fresh milk samples from each of the selected dairy cows were collected aseptically in separate sterilized test tube as RF, RH, LF and LH quarter of the udder. Rapid modified White Side Test(WST) was used to detect subclinical mastitis(SCM). Results of WST and data derived from filled in questionnaire were entered in Microsoft Excel 2003 and transferred to $STATA^{(R)}$, version 8.0/Intercooled(Stata Corporation, Texas, USA, 2003). The overall prevalence of SCM and its distribution in different categories of variables in cow and their exact binomial 95% confidence intervals were calculated in $STATA^{(R)}$. Simple bivariable associations among independent variables were investigated by $x^2$ test in $STATA^{(R)}$. Multiple logistic regression analysis with backward elimination method was used to identify risk factors of SCM. To identify significant variation in quarter SCM, linear regression analysis was performed after arcsine transformation of the data. The overall prevalence of SCM found in this study is 54%. Dairy cows with teat lesions had significantly increased SCM(OR=12342, P value=0.000, 95% CI=762, 199798) than others without teat lesions. The Holstein Friesian X Jersey X Sahiwal breed has significantly decreased(OR=0.18, p=0.03, 95% CI 0.04, 0.85) SCM than other breeds. The prevalence of SCM found in this study is in agreement with others. The injury in the teat increases the probability of getting infected with microbes and thereby mastitis. If the prevalence of teat lesion can be decreased the probability of subclinical mastitis will also be decreased. The negatively associated Holstein Friesian X Jersey X Sahiwall breed may help in planning mastitis control program if this finding can be validated by a more powerful case-control or cohort study design.