• 한국임상수의학회지
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• 제33권2호
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• pp.97-101
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• 2016

In the field of clinical medicine, diagnostic accuracy studies refer to the degree of agreement between the index test and the reference standard for the discriminatory ability to identify a target disorder of interest in a patient. The receiver operating characteristic (ROC) curve offers a graphical display the trade-off between sensitivity and specificity at each cutoff for a diagnostic test and is useful in assigning the best cutoff for clinical use. In this end, the ROC curve analysis is a useful tool for estimating and comparing the accuracy of competing diagnostic tests. This paper reviews briefly the measures of diagnostic accuracy such as sensitivity, specificity, and area under the ROC curve (AUC) that is a summary measure for diagnostic accuracy across the spectrum of test results. In addition, the methods of creating an ROC curve in single diagnostic test with five-category discrete scale for disease classification from healthy individuals, meaningful interpretation of the AUC, and the applications of ROC methodology in clinical medicine to determine the optimal cutoff values have been discussed using a hypothetical example as an illustration.

• 대한전자공학회논문지
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• 제27권9호
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• pp.1336-1343
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• 1990

In this paper the theoretical analysis of the site attenuation was made on the concept of mutual impedance of antennas and the cause of characteristic hump in the site attenuation curve below 80 MHz is explained. The deviation between the FCC site attenuatios and the experimental results of an ideal open area test site at low frequencies(below 80MHz) was found to be the mutual coupling effects of the antennas under the FCC's measurement conditions. It seems desirable that the site attenuations curve of FCC document be revicused to the theoretical curves presented in this paper is long as the FCC's measurement conditions are to the applied.

• 충청수학회지
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• 제16권2호
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• pp.43-57
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• 2003

The boundary of a typical period-2 component in the degree-3 bifurcation set is formulated by a parametrization of its image which is the unit circle under the multiplier map. Some properties on the geometry of the boundary are investigated including the root point, the cusp and the length as well as the area bounded by the boundary curve. The centroid of the area for the period-2 component was numerically found with high accuracy and compared with its center. An algorithm drawing the boundary curve with Mathematica codes is proposed and its implementation exhibits a good agreement with the analysis presented here.

• 대한수학회논문집
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• 제33권1호
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• pp.237-245
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• 2018

For every interval [a, b], we denote by $({\bar{x}}_A,{\bar{y}}_A)$ and $({\bar{x}}_L,{\bar{y}}_L)$ the geometric centroid of the area under a catenary curve y = k cosh((x-c)/k) defined on this interval and the centroid of the curve itself, respectively. Then, it is well-known that ${\bar{x}}_L={\bar{x}}_A$ and ${\bar{y}}_L=2{\bar{y}}_A$. In this paper, we fix an end point, say 0, and we show that one of ${\bar{x}}_L={\bar{x}}_A$ and ${\bar{y}}_L=2{\bar{y}}_A$ for every interval with an end point 0 characterizes the family of catenaries among nonconstant $C^2$ functions.

• Biomolecules & Therapeutics
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• 제7권4호
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• pp.342-346
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• 1999

This study was performed to investigate the effect of cyclosporine (CsA) on glucose tolerance and peripheral insulin sensitivity in normal Sprague-Dawley rats. After daily treament of CsA (10 mg/kg, i.p.) for two weeks, glucose tolerance tests were carried out by the treatment of glucose (Glu, 2 g/kg, i.p.) alone or in conjunction with exogenous insulin (Ins; human regular insulin, 5 U/kg, s.c.) and measured the decrement of area under the time-plasma glucose concentration curve ($AUC_{o\longrightarrow120}$; g.min/ml) by the trapezoidal rule. The rats were divided into three groups (Glu- (Control), Ins+Glu- and CsA+Ins+Glu-, n=7 in each group). The $AUC_{o\longrightarrow120}$ of the CsA+Ins+Glu-group was significantly (p<0.01) lower than that of Glu-group (61.0% of control) and significantly (p<0.05) higher than that of Ins+Glu-group (197.4% of Ins+Glu-). The CsA+Ins+Glu- grou showed higher levels of maximal blood glucose concentration and higher $AUC_{o\longrightarrow120}$ than those of Ins+Glu-group in normal rats. Besides direct pancreatic toxicity of CsA previously reported (Hahn et al., 1972), these results suggest that CsA also make the possibility to induce peripheral insulin insensitivity and glucose intolerance in normal rats.

• 약학회지
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• 제48권4호
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• pp.226-230
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• 2004

The pharmacokinetics of orally administered paclitlxel (50 mg/kg) was studied in six rabbits after 1hr pretreatment (2.0 mg/kg and 10 mg/kg) of tetramethoxyflavone or coadministration of (2.0 mg/kg, 10 mg/kg and 20 mg/kg) tetramethoxyflavone. The area under the plasma concentration-tine curve (AUC) and plasma concentration of paclitaxe1 coadministered with tetramethoxyflavone (10 mglkg) were increased significantly (p<0.05) compared with control. However, coadministration of tetramethoxyflavone (2 and 20 mg/kg) showed no significant effect on the pharmacokinetic parameters of paclitaxel. Pretreatment with tetramethoxyflavone significantly (p<0.05) increased the plasma concentration of paclitaxel. The area under the plasma concentration-time curve (AUC) and the peak concentration (C$_{max}$) of paclitaxel pretreated with tetramethoxyflavone were increased significantly (p<0.01, p<0.05) compared with control. The terminal half. life of paclitaxel pretreated with tetramethoxyflavone (2 mg/kg and 10 mg/kg) was significantly (p<0.05) prolonged compared with control. Pretreatment with tetramethoxyflavone (2.0 mg/kg, 10 mg/kg) significantly (p<0.01, p<0.05) increased the absolute bioavailability of paclitaxel compared with the control (154∼179%). On the basis of the results, it might be considered that tetramethoxyflavone may inhibit cytochrome P450 or P-glycoprotein efflux pump which are engaged in paclitaxel metabolism, result in increased AUC and t$_{1}$2/ of paclitaxel. However, further study should be conducted to clarify the roles of cytochrome P450 and P-glycoprotein on paclitaxel bioavailability with/or without tetramethoxyflavone. P-glycoprotein on paclitaxel bioavailability with/or without tetramethoxyflavone.

• 대한의생명과학회지
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• 제19권3호
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• pp.233-238
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• 2013

Aspirin is still the mainstay of antiplatelet therapy in the cardiovascular and cerebrovascular disease. However, some patients are not responsive to the antithrombotic action of aspirin. The aim of this study was to assess the prevalence and clinical characteristics of aspirin resistance in patients with cerebral infarction. We tested platelet function in 557 patients who had been treated with aspirin in J general hospital. Platelet function was tested using the multiple electrode platelet aggregometry (MEA). Platelet reactivity was expressed as area under the aggregation curve (AUC, U) and >30 AUC was defined as aspirin resistance. Aspirin resistance was detected in 16.2% patients. There was not any significant differences in age, gender between aspirin resistance and aspirin sensitive patients. WBC was significantly higher in patients with aspirin resistance (P < .05). HDL-cholesterol was significantly higher in patients with aspirin sensitive (P < .05). Aspirin resistance was positive correlation with platelet count (r =.314, P =.003). The prevalence of aspirin resistance in cerebral infarction was 16.2%, and platelet count were related with aspirin resistance.

• 대한간호학회지
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• 제46권1호
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• pp.59-68
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• 2016

Purpose: Increase in suicide rate for senior citizens which has become widespread in our society today. It is not a normal social phenomenon and is beyond the danger level. The contents of this study include Korean senior citizens' suicide related risk factors and warning signs, and the development of a simple Geriatric Suicide Risk Scale. Methods: This study is Methodological Research to verify reliability and validity of the Geriatric Suicide Risk Scale according to the tool development process suggested by Devellis (2012). Results: For predictive validity assessment, high suicide screening accuracy was showed with an Area under the ROC curve (AUC) of .93. For the optimal cutoff point of 11, sensitivity was 93.9%, and specificity, 75.7% which are excellence levels. Cross validity for assessment of generalization possibility showed the Area under the ROC curve (AUC) as .82 and in case of a cutoff point of 11, sensitivity was 73.7%, and specificity, 65.9%. Conclusion: When it comes to practical nursing, it is significant that the Korean Geriatric Suicide Risk Scale has high reliability and validity through adequate tool development and the tool assessment step to select degree of suicide risk of senior citizens. Also, it can be easily applied and does not take a long time to administer. Further, it can be used by health care personnel or the general public.

• 약학회지
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• 제44권2호
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• pp.189-192
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• 2000

We examined a dermal pharmacokinetics for a new SYC-fentanyl patch in rabbits. Determination of fentanyl in the plasma was performed using a gas chromatography with nitrogen-phosphorus detection system and a capillary column. One patch per animal (fentanyl 2.5 mg) was applied to clipped back skin for 72 hours. The plasma fentanyl concentration profile of SYC-patch was similar to that of a conventional patch (Durogesi $c^{R}$, Janssen Co.). No significant difference was observed in the pharmacokinetic parameters, the area under the concentration-time curve (AU $C^{0-}$72hrs/) and the total area under the first moment-time curve (AUM $C^{0-}$7hrs/), between the two patch types. The AU $C^{0-}$7hrs/ and AUM $C^{0-}$72hrs/ of durogesi $c^{R}$ were 183.3$\pm$46.28 ng＊hr/ml and 6,450$\pm$1,939ng＊h$r^2$/ml, and those of SYC-fentany patch were 217.2$\pm$50.51$\pm$ng＊hr/ml and 8,022$\pm$2,245ng＊h$r^2$/ml, respectively (n=3). This result indicates that the new SYC patch has a similar bioavailability compared to durogesi $c^{R}$ patch. Therefore, the SYC-patch may be considered as a bioequivalent fentanyl patch.patch.tch.

• 한국음향학회지
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• 제42권3호
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• pp.221-225
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• 2023

본 연구에서는 코로나 바이러스 감염증은 음성만으로 빠르게 진단하는 효율적인 방법을 제안하였다. 기존의 딥러닝 기반 방법들의 연산시간과 대용량 학습자료 요구조건을 완화하기 위해서 Separable Transformer(SepTr)의 구조를 개선하여 파라미터의 수를 대폭 감소시키고 빠른 진단을 가능하게 하는 새로운 Strided Convolution Separable Transformer(SC-SepTr)를 제안하였다. 공개 음향 데이터인 Coswara에 대하여 실험을 수행한 결과 제안된 방법은 상대적으로 소규모의 학습자료에 대해서도 Area Under the Curve(AUC) 성능을 보장하면서도 신속하게 진단을 수행할 수 있음을 보였다.