• Korean Journal of Radiology
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• 제24권6호
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• pp.498-511
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• 2023

Objective: To evaluate the diagnostic performance of chest computed tomography (CT)-based qualitative and radiomics models for predicting residual axillary nodal metastasis after neoadjuvant chemotherapy (NAC) for patients with clinically node-positive breast cancer. Materials and Methods: This retrospective study included 226 women (mean age, 51.4 years) with clinically node-positive breast cancer treated with NAC followed by surgery between January 2015 and July 2021. Patients were randomly divided into the training and test sets (4:1 ratio). The following predictive models were built: a qualitative CT feature model using logistic regression based on qualitative imaging features of axillary nodes from the pooled data obtained using the visual interpretations of three radiologists; three radiomics models using radiomics features from three (intranodal, perinodal, and combined) different regions of interest (ROIs) delineated on pre-NAC CT and post-NAC CT using a gradient-boosting classifier; and fusion models integrating clinicopathologic factors with the qualitative CT feature model (referred to as clinical-qualitative CT feature models) or with the combined ROI radiomics model (referred to as clinical-radiomics models). The area under the curve (AUC) was used to assess and compare the model performance. Results: Clinical N stage, biological subtype, and primary tumor response indicated by imaging were associated with residual nodal metastasis during the multivariable analysis (all P < 0.05). The AUCs of the qualitative CT feature model and radiomics models (intranodal, perinodal, and combined ROI models) according to post-NAC CT were 0.642, 0.812, 0.762, and 0.832, respectively. The AUCs of the clinical-qualitative CT feature model and clinical-radiomics model according to post-NAC CT were 0.740 and 0.866, respectively. Conclusion: CT-based predictive models showed good diagnostic performance for predicting residual nodal metastasis after NAC. Quantitative radiomics analysis may provide a higher level of performance than qualitative CT features models. Larger multicenter studies should be conducted to confirm their performance.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.759-762
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• 1999

The concrete structures possessing good structural integrity can face durability problems due to deteriorations of concrete structures under various environmental conditions. The durability problems weaken the structural integrity in the long run. Especially, the excessive use of sea sand causes serious reinforcement corrosion and carbonation in concrete structures. An accelerated test is often used to predict deterioration as a qualitative measure, but without long term exposure test results or understanding of the relationship between the accelerated test and the long term exposure test, the accelerated test result alone can not be used effectively as a quantitative measure. In this paper, a methodology is proposed to predict the long term deteriorations, based on the result of the short-term accelerated test, of concrete containing different contents of chloride ions. Then, the correlation between two results on the steel corrosion ratio and the carbonation depth is analyzed for concrete with different chloride contents.

• 대한수학교육학회지:학교수학
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• 제13권1호
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• pp.127-153
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• 2011

수학학습에서의 개인차의 문제를 해결하는 현실적인 방법 중 하나가 교실에서 이뤄지는 또래교수이다. 일반적으로 또래교수는 기본학습과정을 먼저 끝낸 학습우수아가 기본학습과정을 이수하는데 어려움이 있는 학습부진아를 도와주는 방식으로 이뤄진다. 따라서 대부분의 또래학습에 관한 연구가 또래교사보다는 또래학습자의 학습에 초점을 맞춰왔고 이런 이유로 부진아 지도를 위한 방법 중 하나로 연구되어졌다. 그러나 또래교수가 학습 부진아에게 효과적인 방법이라고 할지라도 또래교사에게는 스스로 학습할 수 있는 기회를 제한할 뿐 아무런 이득이 되지 않는다면 효율적인 교수학적 방법이라고 보기 어렵고 윤리적이지도 못하다. 본 연구는 또래교수가 또래교사에게 어떤 영향을 미치는 지를 알아보는 것이 목적이다. 이를 위해서 또래교수가 이뤄지기 전과 후의 또래교사의 수학적 성향과 수학적 의사소통 능력의 변화를 살펴보았다.

• 대한간호학회지
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• 제50권6호
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• pp.863-875
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• 2020

Purpose: This study was conducted to develop and test the effects of a program for practice application of intravenous infusion evidence based nursing practice (EBP) guidelines in small and medium-sized hospitals. Methods: A mixed method research design was used, combining non-equivalent control group pre-post test design with qualitative study analysis. The subjects consisted of 55 nurses. The practice application program was developed based on the Advancing Research and Clinical practice through close Collaboration (ARCC) model. Data were collected for analysis in the following areas: nurses' EBP organizational culture and readiness, EBP beliefs, EBP implementation, importance about intravenous infusion, and performance about intravenous infusion, with data assessed using valid and reliable instruments. Patient outcomes were collected from the hospital's medical records. Data were analyzed using t-test, χ2-test, and Shapiro-Wilk test, with qualitative content analysis used for interview data. Results: Following the intervention, nurses' EBP organizational culture and readiness, EBP beliefs, EBP implementation, and performance of intravenous infusion and perceptions of its importance showed significant improvement in the experimental group. Phlebitis rates decreased in the experimental group compared to the control group. Conclusion: This program is effective to improve nurse's perception and practice of evidence based nursing. Therefore we recommend to use this program at same levels of hospitals.

• International Journal of Aeronautical and Space Sciences
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• 제1권2호
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• pp.30-42
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• 2000

On-orbit thermal environment test of KOMPSAT was performed in early 1999. An analysis of the test data are addressed in this paper. For the thermal-environmental simulation of spacecraft bus, an artificial heating through the radiator zones and onto some critical heat-dissipating electronic boxes was made by Absorbed-heat Flux Method. Test data obtained in terms of temperature history were reduced into flight heater duty cycles and converted into the total electrical power required for spacecraft thermal control. Verification result of flight heaters dedicated to the bus thermal control is presented. Additionally, an exhaustive heating-control process for maintaining the spacecraft thermally safe and for realistic simulation of the orbital-thermal environment during the test are graphically shown. Qualitative suggestions to post-test model correlation are given in consequency of the analysis.

• 한국환경보건학회지
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• 제1권1호
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• pp.18-20
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• 1974

A Serological test for Syphilis by VDRL Slide tests were made to find the degree of treponemal infection. For this study sera were collected from 5, 312 Prostitutes of Seoul, Inchun, Euijungbu, Yangzoo, Pajoo and Pyungtaig from November 27, to December 7, 1972 and were examined on the following items. 1. VDRL Slide Qualitative test. 2. VDRL Slide Quantitative test. As the results of this study the following Conclusions were obtained. 1) This test were obtained average reactive 5.92% for 5, 312 prostitutes in Seoul 7.87% for 254 prostitutes, in Iuchun 6.77% for 354 prostitutes, in Euijungbu 6.62% for 740 prostitutes, in Yangjoo 5.82% for 1, 958 prostitutes, in Pajoo 6.08% for 937 prostitutes and in Pyungtaig 4.82% for 1, 069 prostitutes respectively 2) The highest Reagin titer was 1: 32 serum dilution.

• 품질경영학회지
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• 제29권1호
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• pp.61-84
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• 2001

The problem of trend change in the failure rate is great interest in the reliability and survival analysis. In this paper we develop a test statistic for testing whether or not the failure rate changes its trend based on a complete sample. Monte Carlo simulations are conducted to investigate the speed of convergence of the proposed test statistic.

• 초등상담연구
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• 제6권1호
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• pp.171-191
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• 2007

The purpose of this study is to develop social skill training in order to reduce problematic behaviors and improve peer relations for elementary school students who have ADHD(Attention Deficit Hyperactivity Disorder) and then verify its effectiveness. The problems for this study are as follows: Firstly, is the social skill training for students with ADHD effective in enhancing their self-esteem? Secondly, is the social skill training for students with ADHD effective in reducing their carelessness, hyperactivity and impulsive character? Thirdly, is the social skill training for students with ADHD effective in improving peer relations? Subjects were six 5th grade children who were selected by the ADHD-SC4 at P elementary school in Pyeongtaek. The social skill training consisted of 10 sessions which included forming friendship, recognizing, making friends, solving problems, reeducation and evaluation. Qualitative data were collected through self-esteem inventory, peer-relation test, self-reported scales for children and Conners' Teacher rating score for ADHD children. The collected data were analysed with t-test. Qualitative data were collected though teacher's interview and observation an the children. The results of the study were follows: First, the social skill training did not give a significant effect in enhancing the self-esteem of the children with ADHD. Second, the social skill training had a positive effect in reducing in attentiveness, hyperactivity and impulsive behavior of the children with ADHD. Third, the social skill training did not give a significant effect in improving the peer relations of the children with ADHD. Fourth the qualitative data showed that the social skill training had positive effect in enhancing over all classroom behavior.

• 분석과학
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• 제33권1호
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• pp.23-32
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• 2020

Methamphetamine (MA) is the most common and available drug of abuse in Korea and its primary metabolite is amphetamine (AP). Detection of AP derivatives, such as MA, AP, phentermine (PT), MDA, MDMA, and MDEA by the use of immunoassay screening is not reliable and accurate due to cross-reactivity and insufficient specificity/sensitivity. Therefore, the analytical process accepted by most urine drug-testing programs employs the two-step method with an initial screening test followed by a more specific confirmatory test if the specimen screens positive. In this study, a gas chromatography-mass spectrometric (GC-MS) method was developed and validated for confirmation of MA and AP in human urine. Urine sample (500 µL) was added with N-isopropylbenzylamine as internal standard and ethyl chloroformate as a derivatization reagent, and then extracted with 200 µL of ethyl acetate. Extracted samples were analysed with GC-MS in the SIM/ Scan mode, which were screened by Cobas c311 analyzer (Roche/Hitachi) to evaluate the efficiency as well as the compatibility of the GC-MS method. Qualitative method validation requirements for selectivity, limit of detection (LOD), precision, accuracy, and specificity/sensitivity were examined. These parameters were estimated on the basis of the most intense and characteristic ions in mass spectra of target compounds. Precision and accuracy were less than 5.2 % (RSD) and ±14.0 % (bias), respectively. The LODs were 3 ng/mL for MA and 1.5 ng/mL for AP. At the screening immunoassay had a sensitivity of 100% and a specificity of 95.1 % versus GC-MS for confirmatory testing. The applicability of the method was tested by the analysis of spiked urine and abusers' urine samples.

• Journal of Cancer Prevention
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• 제23권4호
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• pp.176-182
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• 2018

Background: Family physicians (FPs) play an important role in cancer control. The aim of this study was to understand the functions of FPs in cancer control and to explore FPs' perceptions of their own roles and the difficulties they face in cancer control in Karabuk province, Turkey. Methods: The study consisted of two methodological parts. The qualitative part included a descriptive study in which data were collected from 87.5% (n=56) out of all FPs in Karabuk using a questionnaire. In the quantitative part, in-depth interviews with 15 FPs were conducted and analyzed through content analysis. Results: Half of the FPs (50.0%) provided cancer prevention information for their registered people, focusing on especially smoking cessation. In the last three months, the proportion of FPs who had not invited anyone to screenings was 37.5% for the pap test, 26.8% for the mammography, 19.0% for the fecal occult blood test and 34.5% for the colonoscopy. Only 16.1% of them reported that they made home visits for cancer patients. In the qualitative part of study, the following themes were highlighted: the perceived responsibilities of FPs regarding cancer control; the effect of geographically undefined working area of FPs; the issues with coordination between FPs and specialists; the effect of the number of primary care team members. Conclusions: Cancer control services provided by FPs have significant problems in terms of the FPs' approach to the services and their content, continuity and coordination.