• Journal of Intelligence and Information Systems
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• v.25 no.1
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• pp.127-137
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• 2019

Recidivism prediction has been a subject of constant research by experts since the early 1970s. But it has become more important as committed crimes by recidivist steadily increase. Especially, in the 1990s, after the US and Canada adopted the 'Recidivism Risk Assessment Report' as a decisive criterion during trial and parole screening, research on recidivism prediction became more active. And in the same period, empirical studies on 'Recidivism Factors' were started even at Korea. Even though most recidivism prediction studies have so far focused on factors of recidivism or the accuracy of recidivism prediction, it is important to minimize the prediction misclassification cost, because recidivism prediction has an asymmetric error cost structure. In general, the cost of misrecognizing people who do not cause recidivism to cause recidivism is lower than the cost of incorrectly classifying people who would cause recidivism. Because the former increases only the additional monitoring costs, while the latter increases the amount of social, and economic costs. Therefore, in this paper, we propose an XGBoost(eXtream Gradient Boosting; XGB) based recidivism prediction model considering asymmetric error cost. In the first step of the model, XGB, being recognized as high performance ensemble method in the field of data mining, was applied. And the results of XGB were compared with various prediction models such as LOGIT(logistic regression analysis), DT(decision trees), ANN(artificial neural networks), and SVM(support vector machines). In the next step, the threshold is optimized to minimize the total misclassification cost, which is the weighted average of FNE(False Negative Error) and FPE(False Positive Error). To verify the usefulness of the model, the model was applied to a real recidivism prediction dataset. As a result, it was confirmed that the XGB model not only showed better prediction accuracy than other prediction models but also reduced the cost of misclassification most effectively.

• The Korean Journal of Nuclear Medicine
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• v.34 no.3
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• pp.234-242
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• 2000

Purpose: Tc-99m MIBI scintimammography has been validated as an useful non-invasive diagnostic tool for the primary breast cancer. But most studies have included small population of patients. We have experienced a large study population and investigated the diagnostic usefulness of Tc-99m MIBI scintimammography in detection of primary breast cancer and axillary lymph node metastasis. Materials and Methods: This study included 305 patients who underwent scintimammogtaphy for palpable breast masses or abnormal radiologic findings. Tc-99m MIBI scintimammography was performed 10 minutes after intravenous injection of 925 MBq of Tc-99m MIBI. If the early image revealed abnormal finding, 3 hour delayed image was also acquired. We calculated early and delayed lesion to non-lesion ratios (L/N). The pathologic diagnosis was obtained from surgical operation or FNAB and compared with the results of Tc-99m MIBI scintimammography. Results: Malignant breast diseases were 155 and benign ones were 150. Tc-99m MIBI scintimammography revealed 132 true positive, 23 false negative, 10 false positive, and 140 true negative cases. The sensitivity, specificity, positive predictive value and negative predictive value for the primary breast cancer detection were 85.2%, 93.4%, 92.9%, and 85.9%, respectively. The sensitivity, specificity, positive predictive and negative predictive values of Tc-99m MIBI scintimammography in detecting metastatic axillary lymph node involvement were 22%, 90.4%, 61.9% and 62.3%, respectively. Early L/N of malignant breast disease was significantly higher than that of benign one ($2.44{\pm}0.97\;vs\;1.94{\pm}0.78$, p=0.01). Delayed L/N had no significant difference between malignant and benign breast diseases ($1.94{\pm}0.52\;vs\;1.91{\pm}0.73$, p=0.43). Conclusion: Our study revealed that Tc-99m MIBI scintimammography was an useful diagnostic tool for the diagnosis of breast cancer. And early L/N ratio might provide complementary role in the detection of breast cancer. But the Tc-99m MIBI scintimammography had limited value in the detection of small breast cancer (less than 1 cm) and axillary lymph node metastasis.

• Nuclear Medicine and Molecular Imaging
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• v.41 no.6
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• pp.546-552
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• 2007

Purpose: In the breast cancer patient, lymphatic mapping and sentinel lymph node biopsy are the most important procedure for axillary lymph node staging. We aimed to compare the three radiocolloids [$^{99m}Tc$-antimony trisulfide colloid (ASC), $^{99m}Tc$-tin colloid (TC), and $^{99m}Tc$-human serum albumin (HSA)] for sentinel lymph node mapping. Subjects and Methods: Totally, 397 patients with clinically N0 stage were enrolled. $^{99m}Tc$-ASC was injected in 202 out of 397 patients, $^{99m}Tc$-TC was injected in 120 patients, and $^{99m}Tc$-HSA was injected in the remaining 75 patients. The sentinel lymph nodes were localized by lymphoscintigraphy and selected using intraoperative gamma probe. All sentinel lymph nodes were investigated by intraoperative pathologic consultation. The axillary lymph nodes which were harvested by the lymph node dissection were also investigated. Results: The patients of each group showed similar clinical characteristics. There were no significant differences (p>0.05) in the identification rate of sentinel lymph nodes (IR), false negative rate (FNR), and negative predictive value (NPV). The axillary lymphadenectomy revealed axillary lymph node metastases in those three groups (ASC-33.2%, TC-31.7%, HSA-22.7%). The IR, FNR, and NPV were not significantly different among those groups. Conclusion: Those three $^{99m}Tc$-labeled radiocolloids showed equivalent results in sentinel lymph node mapping of breast cancer.

• Journal of Breast Cancer
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• v.21 no.4
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• pp.433-4341
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• 2018

Purpose: This study aimed to evaluate the effects of sentinel lymph node biopsy (SLNB) on recurrence and survival after neoadjuvant chemotherapy (NAC) in breast cancer patients with cytology-proven axillary node metastasis. Methods: We selected patients who were diagnosed with invasive breast cancer and axillary lymph node metastasis and were treated with NAC followed by curative surgery between January 2007 and December 2014. We classified patients into three groups: group A, negative sentinel lymph node (SLN) status and no further dissection; group B, negative SLN status with backup axillary lymph node dissection (ALND); and group C, no residual axillary metastasis on pathology with standard ALND. Results: The median follow-up time was 51 months (range, 3-122 months) and the median number of retrieved SLNs was 5 (range, 2-9). The SLN identification rate was 98.3% (234/238 patients), and the false negative rate of SLNB after NAC was 7.5%. There was no significant difference in axillary recurrence-free survival (p=0.118), disease-free survival (DFS; p=0.578) or overall survival (OS; p=0.149) among groups A, B, and C. In the subgroup analysis of breast pathologic complete response (pCR) status, there was no significant difference in DFS (p=0.271, p=0.892) or OS (p=0.207, p=0.300) in the breast pCR and non-pCR patients. Conclusion: These results suggest that SLNB can be feasible and oncologically safe after NAC for cytology-determined axillary node metastasis patients and could help reduce arm morbidity and lymphedema by avoiding ALND in SLN-negative patients.

• Journal of Yeungnam Medical Science
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• v.16 no.2
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• pp.169-180
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• 1999

Background: Uterine cervical cancer is the most common malignant tumor of the women in Korea. This study was undertaken to evaluate the usefulness of the cervicography as a screening test of cervical cancer. Materials and Methods: Cervicography was taken from 482 women at department of obstetrics and gynecology, at Yeungnam University Hospital from March 1, 1998 to October 31, 1999. Of the 482 women, 172 women were exc1uded from the study for various reasons, and 310 women completed the study. Three-hundred and ten women had cervical cytology (Papanicolaou smear), cervicography and colposcopy, and punch biopsy was undertaken if any of the test result was abnormal. Results: The most common age group was 35-39, and 40-44, 45-49 in order and most common reason for having a screening test was regular check for cervical cancer. The mean duration from the last Pap smear was 17.1 months, and 64 women(20.4%) never had any prior screening tests. Of the 310 women, 254 women were categorized as normal or having benign disease such as cervicitis, erosion or metaplasia. Biopsy was taken from 56 patients and the results were 26 chronic cervicitis, 4 mild dysplasia, 6 moderate dysplasia, 2 severe dysplasia, 14 carcinoma in situ and 4 invasive carcinoma. The results of cytology and cervicography were well correlated(p<0.05). The sensitivity and specificity of cytology were 86.7% and 76.9%, respectively and the sensitivity and specificity of cervicography were 56.7% and 96.2%, respectively. False negative rate of cervicography(43.3%) was much higher than those of cytology(13. 3%) (p<0.05), but false positive rate of cervicography(3.8%) was much lower than that of cytology(23.1%) (p<0.05). Conclusion: It seems inappropriate to use cervicography as a single screening test for cervival cancer, but it may be an effective complementary test for cytology to lower the false negative rate of cytology.

• The Korean Journal of Cytopathology
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• v.15 no.1
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• pp.40-44
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• 2004

To evaluate the quality of fine needle aspiration cytology diagnosis on malignant salivary gland neoplasms, cytologic findings were correlated with histologic diagnosis of 56 surgically removed malignant salivary gland tumors. Seven cases (12.5%) were insufficient, 23 cases (41.1%) were diagnosed as malignant, 17 (30.4%) cases were accurately diagnosed by histologic subtype, and 9 cases (16%) were diagnosed as benign. Five out of 9 false negative cases were misdiagnosed as pleomorphic adenomas. Except the cases with insufficient specimen, overall sensitivity was 81.6%, and the sensitivity varied according to the histologic subtype; 91% in salivary duct carcinoma, 100% in carcinoma ex pleomorphic adenoma, 50% in mucoepidermoid carcinoma, 63% in adenoid cystic carcinoma, and 50% in acinic cell carcinoma. The diagnostic accuracy differed among cytopathologists irrespective of periods after acquisition of board of pathologists. These results confirm that salivary gland neoplasm can be easily misdiagnosed in fine needle aspiration cytology and a great caution should be given in diagnosing the benign appearing salivary aspirates to avoid under-diagnosis of malignant neoplasm with low grade cytologic atypia.

• Journal of Microbiology
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• v.44 no.1
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• pp.72-76
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• 2006

Plasma-derived products are produced from plasma via fractionation and chromatography techniques, but can also be produced by other methods. In the performance of nucleic acid amplification tests (NAT) with plasma-derived products, it is necessary to include an internal control for the monitoring of all procedures. In order to avoid false negative results, we confirmed the usefulness of the bovine viral diarrhoea virus (BVDV) for use as an internal control in the detection of hepatitis C virus (HCV) RNA in plasma-derived products. These products, which were spiked with BVDV, were extracted and then NAT was performed. Specificity and sensitivity were determined via the adjustment of primer concentrations and annealing temperatures. BVDV detection allows for validation in the extraction, reverse transcription, and amplification techniques used for HCV detection in plasma-derived products.

• The Korean Journal of Nuclear Medicine
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• v.27 no.2
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• pp.298-304
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• 1993

To estimate the bone marrow involvement of leukemia, we peformed scintigraphies using $^{99m}Tc$ antimony sulfide colloid and Gallium-67. Total 13 patients were included and obtained 14 study sets of $^{99m}Tc$ antimony sulfide colloid and gallium-67 and compared with bone marrow aspiration biopsy and clinicolaboratory datas. $^{99m}Tc$ Antimony scan showed localized defect in 4 patients who had relapse. No false positive or negative results were observed. Gallium 67 showed localized increased uptake in 2 of 4 relapsed patients. Therefore, bone marrow scan is useful for the evaluation of marrow infiltration in ieukemic patients.

• Journal of Oriental Neuropsychiatry
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• v.24 no.3
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• pp.229-244
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• 2013

Objectives : The purpose of this study was to provide information about Maumgongbu to meet the needs of people by analysing the concept of Maumgongbu in group counseling. Methods : This study was conducted using Walker and Avant's Concept Analysis Strategy. Dictionaries, Wonbuddhism's Kyunjions and literatures, and participants' journals were reviewed after enrolling in Onsarm maumgongbu group counseling. Results : The attributes of the Maumgongbu include emotion, object, self-reflection, attribution, and creativity. The antecedents of "Maumgongbu" are the conditions arising from negative emotions. The Maumgongbu helps people find the emotional causality of their inner self by self-reflecting, getting out of false belief, restoring positive emotions, maintaining healthy and warm relationships with oneself, family, friends and society. Above all, the Maumgongbu makes people experience tranquility and true happiness and activate their positive energy or power. Conclusions : If there is a clear indication of linkage to principles, attributions, precedents and consequences, and empirical referents to any of Maumgongbu programs, there is no doubt that our understanding of the human mind and lives will be greatly enriched. Furthermore, self-discipline and steadfast complements give us calmness, peacefulness and better quality of life.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.4
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• pp.1820-1840
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• 2017

Aiming at the phenomenon of false information issued by service providers in cloud computing environment, a method for service evaluation based on fuzzy theory is put forward in this paper. According to the quality of services provided by cloud service providers and their behavior during interactions, a trust relationship between cloud service providers and cloud service consumers is established, which can be quantified by using fuzzy theory. The quality of services is evaluated by drawing on the trust relationship. In our method, the recommendation credibility of a cloud service consumer is determined through behavior similarity with evaluators and a praise factor. The introduction of the praise factor better suits the phenomenon of a high-quality service getting more repeat customers. The negative impact of dishonest customers is reduced, and the accuracy of trust and cloud service quality evaluation is improved by introducing a confidence factor that can be dynamically adjusted. The experimental results show that our method can effectively and accurately evaluate the trust value and service quality of providers, while weakening the influence of dishonest consumers, and quickly detect dishonest service providers. This is beneficial for consumers trying to find high quality service providers for similar services.