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A Study on Availability about Positron Emission Mammography of Breast Cancer (유방암 환자의 Positron Emission Mammography에서의 유용성에 관한 연구)

  • Kim, Seung-Jeong;Kim, Jae-Il;Kim, Jin-Eui;Kim, Hyun-Joo
    • The Korean Journal of Nuclear Medicine Technology
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    • v.14 no.2
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    • pp.60-64
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    • 2010
  • Purpose: Until now the general study for breast cancer patient has been mammography, breast sonography for anatomic diagnostics and $^{18}F$-FDG whole body PET for functional one. But the PEM (Positron Emission Mammography) was developed to increase sensitivity, specificity and accuracy to improve the disadvantage of each study. Therefore this present study aims to describe availability of PEM for improving diagnosis of breast cancer. Materials and Methods: During 3 months from January in 2010, PEM was performed on 100 patients who had history of breast cancer. Using Naviscan's PEM Flex Solo II scanner, PEM images of breast were acquired. And then we evaluated sensitivity, specificity and accuracy of PEM data by comparing results of PEM images with postoperative pathologic finding. Results: On the 100 patients, it could reveal 89 true positive, 9 false positive, 7 false negative and 87 true negative. Thus the results of sensitivity, specificity and accuracy for PEM was evaluated 92.7%, 90.6% and 91.7%. Conclusion: The sensitivity, specificity and accuracy have been reported 83.7%, 68.5% and 77.1% in mammography, and that was 89.1%, 79.1% and 83.4% in breast sonography. However the results of PEM were more increased than others. Therefore the results of this study will be available that PEM used diagnosis with breast cancer, used preoperative operation plan and helps to discovery of a part recurrence.

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Sensitivity of AutoPap Primary Screening System with Location-Guided Screening in Uterine Cervical Cytology (자궁목세포진에서의 AutoPap Primary Screening System with Location-Guided Screening의 민감도 검사)

  • Choi, Jong-Sun;Jang, Hoi-Sook;Kim, Hy-Sook;Chun, Yi-Kyeong;Kim, Hye-Sun;Park, Ji-Young;Park, In-Sou;Hong, Sung-Ran
    • The Korean Journal of Cytopathology
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    • v.14 no.2
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    • pp.60-65
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    • 2003
  • Objective: The sensitivity of the AutoPap Primary Screening System with Location-Guided Screening (AutoPap LGS) for Identifying atypical cells in cervicovaginal smears was evaluated. Methods: Two hundred forty one slides with atypical cervical cytology randomly sampled were rescreened both manually and by the AutoPap LGS. The AutoPap LGS localized the atypical cells as 15 fields of view(FOVs), which were reexamined by manual review. The sensitivity was also evaluated in accordance with the cellularity of the smears. Results: The AutoPap LGS successfully processed 232 out of 241 slides. The sensitivity of the AutoPap LGS identifying the atypical cells in successfully processed slides was 97.4%(226/232). The false negative rate was 2.6%(6/232). There was no false negative case on high grade squamous intraepithelial lesion (HSIL) or squamous cell carcinoma(SCC) smears in the AutoPap LGS. The FOVs localized the diagnostic-atypical cells in 97.8%(221/226). The number of diagnostic-atypical FOVs was increased in higher-degree of atypical cytology. The AutoPap LGS localized the atypical cells in 100% of adequately cellular smears and in 92.5% even in low cellular smears. Conclusion: The AutoPap LGS showed relatively good sensitivity to detect atypical cells. It can be a valuable system to localize atypical cells, especially in HSIL or cancer slides, even in smears with low cellularity.

Design of NePID using Anomaly Traffic Analysis and Fuzzy Cognitive Maps (비정상 트래픽 분석과 퍼지인식도를 이용한 NePID 설계)

  • Kim, Hyeock-Jin;Ryu, Sang-Ryul;Lee, Se-Yul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.4
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    • pp.811-817
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    • 2009
  • The rapid growth of network based IT systems has resulted in continuous research of security issues. Probe intrusion detection is an area of increasing concerns in the internet community. Recently, a number of probe intrusion detection schemes have been proposed based on various technologies. However, the techniques, which have been applied in many systems, are useful only for the existing patterns of probe intrusion. They can not detect new patterns of probe intrusion. Therefore, it is necessary to develop a new Probe Intrusion Detection technology that can find new patterns of probe intrusion. In this paper, we proposed a new network based probe intrusion detector(NePID) using anomaly traffic analysis and fuzzy cognitive maps that can detect intrusion by the denial of services attack detection method utilizing the packet analyses. The probe intrusion detection using fuzzy cognitive maps capture and analyze the packet information to detect syn flooding attack. Using the result of the analysis of decision module, which adopts the fuzzy cognitive maps, the decision module measures the degree of risk of denial of service attack and trains the response module to deal with attacks. For the performance evaluation, the "IDS Evaluation Data Set" created by MIT was used. From the simulation we obtained the max-average true positive rate of 97.094% and the max-average false negative rate of 2.936%. The true positive error rate of the NePID is similar to that of Bernhard's true positive error rate.

An Experimental Study for the Prevention of CT Contrast Media Extravasation with Extravasation Detection Accessory System in Femoral Vein of Rabbit (가토 정맥에서 CT 조영제의 혈관외유출 예방을 위한 EDA 시스템의 실험적 연구)

  • Kweon, Dae-Cheol;Jeong, Seok-Hee;Yang, Sung-Hwan;Cho, Mun-Son;Jang, Keun-Jo;Kim, Sun-Geun;Yoo, Beong-Gyu;Lee, Jong-Seok
    • Progress in Medical Physics
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    • v.17 no.4
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    • pp.238-245
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    • 2006
  • To assess the ability of an extravasation defection accessory (EDA) to detect the clinically important extravascular Injection of iodinated contrast material that was delivered with an automated mechanical power injector. The purpose of this study was to assess the ability of this device during clinically important episodes of extravasation. The EDA system was composed of a strain gage, an amplifier and a computer-based system. In the rabbit experimental cases, there were seven true-positive cases (range of the extravasation volumes: $14{\sim}23 ml$). The algorithm results showed seven true-positive cases (range of the extravasation volumes: $7{\sim}16ml$), nineteen true-negative cases, two false-positive cases and no false-negative cases. The EDA system had a sensitivity of 100% and a specificity of 90% for the detection of clinically important extravasation. The EDA system had good sensitivity for the detection of clinically important extravasation and the EDA system has the clinical potential for the early detection of extravasation of the contrast medium that is administered with power injectors.

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A Study on the Detection and Statistical Feature Analysis of Red Tide Area in South Coast Using Remote Sensing (원격탐사를 이용한 남해안의 적조영역 검출과 통계적 특징 분석에 관한 연구)

  • Sur, Hyung-Soo;Lee, Chil-Woo
    • The KIPS Transactions:PartB
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    • v.14B no.2
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    • pp.65-70
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    • 2007
  • Red tide is becoming hot issue of environmental problem worldwide since the 1990. Advanced nations, are progressing study that detect red tide area on early time using satellite for sea. But, our country most seashores bends serious. Also because there are a lot of turbid method streams on coast, hard to detect small red tide area by satellite for sea that is low resolution. Also, method by sea color that use one feature of satellite image for sea of existent red tide area detection was most. In this way, have a few feature in image with sea color and it can cause false negative mistake that detect red tide area. Therefore, in this paper, acquired texture information to use GLCM(Gray Level Co occurrence Matrix)'s texture 6 information about high definition land satellite south Coast image. Removed needless component reducing dimension through principal component analysis from this information. And changed into 2 principal component accumulation images, Experiment result 2 principal component conversion accumulation image's eigenvalues were 94.6%. When component with red tide area that uses only sea color image and all principal component image. displayed more correct result. And divided as quantitative,, it compares with turbid stream and the sea that red tide does not exist using statistical feature analysis about texture.

Captopril $^{99m}Tc-DTPA$ Renal Scintigraphy in Diagnosis of Renovascular Hypertension (신혈관성 고혈압의 진단에 있어서 캅토프릴 신스캔의 의의)

  • Yang, Hyung-In;Lee, Dong-Soo;Kim, Sung-Chul;Bae, Sang-Kyun;Choi, Chang-Woon;Chung, June-Key;Kim, Suhng-Gwon;Lee, Myung-Chul;Lee, Jung-Sang;Koh, Chang-Soon
    • The Korean Journal of Nuclear Medicine
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    • v.26 no.2
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    • pp.312-317
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    • 1992
  • To evaluate the sensitivity and specificity of captopril renal scan for renovascular hypertension, we employed the captopril renal scan in conjunction with renal angiography in 81 patients, 159 kidneys, who were referred to evaluate the cause of hypertension. We defined the renovascular hypertension by the criteria of demonstration of renal artery stenosis by angiography, and improvement or cure of hypertension by revascularization. Visual and quantitative evaluation of $^{99m}Tc-DTPA$ renal scan was peformed pre and post captopril administration. The prevalence rate of renovascular hypertension was 40% in comparing with renal angiography, and 70% in confirmed cases. The causes of renovascular hypertension in 81 patients were Takayasu's arteritis, fibromuscular dysplasia, atherosclerosis, essential hypertension, chronic pyetonephritis etc. The sensitivity and specificity of captopril renal scan in comparing with renal angiography were 80%, 86.5%, respectively and also 84.2%, 72.6% in confirmed cases of renovascular hypertension, respectively. The causes of false negative cases were nonfunctioning kidney due to complete obstruction or long duration of disease in basal scan, segmental branch artery stenosis, unknown causes, and suspicious true negative cases without confirmation. The false positive cases were abdominal aortic stenosis or aneurysm, dehydration, unknown causes, and suspicious true positive cases. We conclude that captopril renal scintigraphy is highly sensitive, reasonably specific diagnostic method and comparable to other techniques very favorably.

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Diagnostic effectiveness of fine needle aspiration cytology on pediatric cervical lymphadenopathy (소아 경부 림프절 종대의 세침 흡인 세포검사의 진단적 유용성)

  • Byun, Jun Chul;Choe, Byung Kyu;Hwang, Jin-Bok;Kim, Heung Sik;Lee, Sang Sook
    • Clinical and Experimental Pediatrics
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    • v.49 no.2
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    • pp.162-166
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    • 2006
  • Purpose : There are few reports in Korean literature on the diagnostic efficacy of fine needle aspiration cytology(FNAC) for pediatric cervical lymphadenopathy. This study examined the diagnostic value of FNAC on cervical lymphadenopathy in children. Methods : Data from 57 pediatric patients(aged 0.3 to 14 years) who underwent FNAC due to cervical lymphadenopathy between January 2001 and March 2005 was reviewed retrospectively. Results : Reactive cervical lymphadenitis was the most common result of the FNAC(52.5 percent). Malignant disease were revealed in 14 percent of all cases. The sensitivity, specificity was 86 percent and 96 percent, respectively. The positive and negative predictive values for malignant disease was 75 percent and 98 percent, respectively. There were two false-positive cases on FNAC; one case of Langerhans cell histiocytosis, and another with infectious mononucleosis. A false-negative case on FNAC was found to be acute lymphocytic leukemia. In seven cases(12 percent), the final diagnosis was confirmed by an open biopsy after the FNAC. There were four FNAC cases where the specimen was not satisfactory for making a diagnosis(7 percent). There were no serious complications of the FNAC procedure. Conclusion : FNAC had a high diagnostic efficacy for evaluating children with cervical lymphadenopathy.

Teachers' Recognition of Victims of School Bullying Using Data from the Adolescents' Mental Health and Problem Behavior Screening Questionnaire-II Standardization Study in Korea (청소년정서행동발달검사 표준화 연구 자료를 활용한 교사의 학교폭력 피해자 인지도)

  • Hwang, Jun-Won;Bhang, Soo-Young;Yoo, Han-Ik K.;Kim, Ji-Hoon;Kim, Bong-Seog;Ahn, Dong-Hyun;Suh, Dong-Su;Cho, Soo-Churl;Bahn, Geon-Ho;Lee, Young-Sik
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.23 no.2
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    • pp.69-75
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    • 2012
  • Objectives : The current study was conducted in order to investigate teachers' recognition of school bullying using a nationwide database of adolescents in middle and high school in Korea. Methods : Students in the 7th to 12th grades at 23 secondary schools participated in the current study during the fall of 2009. Subjects completed the self-report form of the Adolescent Mental Health and Problem Behavior Screening Questionnaire-II (AMPQ-II) and Symptom Checklist-90 Revised (SCL-90-R). In addition, relevant teachers used the teachers' rating scale of the AMPQ-II to report their students' status. Differences in the number of bullied students between teachers' recognition and students' report were explored. Results : A total of 2270 subjects provided relevant responses to the questionnaire. While the one-month prevalence of victimization according to students' self-reports was 28.9%, the recognized prevalence by teachers was only 10.6%. For prediction of the presence of school bullying according to students' self reports on the AMPQ-II, item 7 of the teachers' report on the AMPQ-II showed a sensitivity of 16%, a specificity of 92%, a positive predictability of 44%, a negative predictability of 72%, a false positive rate of 8%, a false negative rate of 84%, and an accuracy of 69%, respectively. No significant differences in subscores of students' self reports of the AMPQ-II and SCL-90-R were observed between bullied students who were recognized by teachers and those who were not recognized. In stepwise discriminant analysis, classification of teachers' item 2 and item 7 on the AMPQ-II with respect to school bullying according to students' reports showed an accuracy of 63.4%. Using this model, 75.2% of non-victimized subjects were classified correctly, while only 35.2% of victimized subjects were classified correctly. Conclusion : Despite the high prevalence in Korea, teachers' recognition of school violence among their students remains low. Pre-professional and continuing education to improve teachers' understanding of school bullying and knowledge of effective classroom-based prevention activities should be encouraged.

A Study on the Influence of Digital Experience and Purchase in the 4th Industrial Revolution : Focusing on Differences between Satisfied, Neutral, and Dissatisfied Groups

  • Jung, Sang Hee;Lee, Sang-Jik
    • Journal of Information Technology Applications and Management
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    • v.26 no.4
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    • pp.51-69
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    • 2019
  • One of the most considerate phenomena of the era of the Fourth Industrial Revolution is the use of digital devices. Digitalization is rapidly advancing through all areas of industry and life. Customer journey with digitalization is looking totally different from previous customer journey. The research targets were users of fashion, automobiles, cosmetics and online shopping malls. We analyzed 300 people for each valid questionnaire. The results of the study are as follows. First, it has been proven that digital experience affects positive (+) impact on purchasing intention and positive (+) impact on recommending intention and negative impact (-) on switching intent and subsequently affects positive impact (+) to purchase and incase of switching intent, negative impact (-) to purchase. Unlike traditional methods such as SPC(Service Profit Chain), the Digital experience to Purchase process Chain (DPC) has been identified to be suitable in the digital age. Second, the digital satisfied group (5 score-very satisfaction) has shown same result as above. However the digital neutral group (even though 4 score- satisfaction in five-point scale), specially in a highly competitive industry, has different from the satisfied group and 3 score-normal is same as dissatisfied group. It means that this group is that If there is a high level of attractiveness of substitute goods, there is a high possibility of switching them. It has supported Jones and Sasser [1995] that there have been two types of loyalty of true long-term loyalty and what we call false loyalty in the highly competitive industry zone which is commoditization or low differentiation, many substitutes, low cost of switching. Identifying true loyalty and false loyalty is crucial to establishing a customer experience strategy. it is necessary to actively utilize long-term digital experiences strategy to increase the total satisfaction of digital experience through all of customer purchasing journey in order to enhance the digital customer experience. It is difficult to see the effect as a one-time event. It should be scaled over the entire customer purchase process over a long period of time, which can positively affect purchase intention, recommendation intention, and conversion intention. This is also why it is difficult for second-runners to overtake first-runners in a short period.

An Experimental Study for Performance Evaluation in Dogs of Preventive Contrast Media Extravasation with a Strain Gage Based Prototype Extravasation Detection Accessory System (잡견에서 조영제 혈관외유출 예방을 위한 스트레인 게이지 기반의 EDA 시스템 성능 평가를 위한 실험적 연구)

  • Kweon, D.C.;Yoo, B.G.;Lee, J.S.;Cho, M.S.;Yang, S.H.
    • Journal of Biomedical Engineering Research
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    • v.29 no.1
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    • pp.66-72
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    • 2008
  • The major risk associated with the use of automated power injectors is the well known complication of contrast material extravasation at the injection site. Automated injection of computed tomography (CT) contrast media can produce the compartment syndrome. The purpose of this study was to assess the ability of this device during clinically important episodes of extravasation. The extravasation detection accessory (EDA) system was composed of a strain gage, an amplifier and a computer based system. A strain gage pliable adhesive patch was applied to the skin aver the intravenous catheter and the catheter was connected to the power injector with a cable to monitor the resolution data. If the programmed monitoring, which was developed with MS Visual C++, at the extravasation occurred, then the injection was interrupted the auto injector. CT was used to demonstrate the clinically important extravasation. This study was a prospective, observational study in which the EDA system was used to monitor the automated mechanical injection of contrast material in 7 dogs. There were two true-positive cases (range of extravasation volumes: $18{\sim}22ml$), twenty three true-negative cases, three false-positive cases and no false-negative cases. The EDA system had a sensitivity of 100% and a specificity of 88% for the detection of clinically important extravasation. The EDA system had good sensitivity for the detection of clinically important extravasation and the EDA system has the clinical potential for the early detection of extravasation of the contrast medium that is administered with power injectors. The EDA system is easy to use safe and accurate for the monitoring extravasation of the intravenous injections, and this system may prove especially useful in CT applications.