• Journal of the Korean Society of Radiology
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• v.83 no.1
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• pp.3-27
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• 2022

Cardiac CT has been proven to provide diagnostic and prognostic evaluation of coronary artery disease for cardiovascular risk stratification and treatment decision-making based on rapid technological development and various research evidence. Coronary CT angiography has emerged as a gateway test for coronary artery disease that can reduce invasive angiography due to its high negative predictive value, but the diagnostic specificity is relatively low. However, coronary CT angiography is likely to overcome its limitations through functional evaluation to identify the hemodynamic significance of coronary artery disease by analyzing myocardial perfusion and fractional flow reserve through cardiac CT. Recently, studies have been actively conducted to incorporate artificial intelligence to make this more objective and reproducible. In this review, functional imaging techniques of cardiac computerized tomography are explored.

• Journal of the Korean Society of Radiology
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• v.81 no.2
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• pp.250-271
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• 2020

Assessment of myocardial ischemia in patients with stable angina is important in deciding whether to treat coronary artery disease and in predicting clinical outcome. The fractional flow reserve is a standard reference for the diagnosis of myocardial ischemia, but this procedure has limitations because of its invasiveness. Coronary computed tomography angiography (CCTA) is now an established tool in the anatomic diagnosis of coronary artery disease; however, there are limits to the diagnosis of hemodynamically important stenosis that causes myocardial ischemia. In order to address this problem, studies using quantification of coronary atherosclerotic plaques, myocardial perfusion, and noninvasive calculation of fractional flow reserve based on CCTA have been actively conducted and recognized for their diagnostic value. In this review, several imaging techniques of CCTA used to assess myocardial ischemia are described.

• Journal of the Korean Society for information Management
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• v.41 no.1
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• pp.85-105
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• 2024

Augmented Reality (AR) is a mix of the real world that is enhanced by virtual objects from computer-generated information. AR is currently used in a variety of information systems and library services. AR technologies are also being developed for today's children, who are digital natives and are exposed to various technologies even earlier. To assist librarians who need to accurately understand users' information needs and perceptions of the technology being used in their libraries, we conducted a study of AR perceptions among children. We conducted two online co-design sessions using "Would you rather?", a co-design technique that facilitates research into children's opinions. Through the co-design sessions, we found that children were psychologically wary about AR technology due to a lack of trust in the technology, and realism had a significant impact on these judgments. We also identified that children considered AR technology environments as an extension of the real world. Their real-world values directly influenced their perceptions of AR. This research provides insights into the wariness that libraries need to be aware of when developing AR content for children in the future, and how libraries can use AR as an educational tool.

• Journal of Chest Surgery
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• v.37 no.7
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• pp.585-590
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• 2004

Bronchogenic cyst is a rare and benign disease. Because of its complication or associated disease, Bronchogenic cyst requires surgical treatment. Recently, with the development of diagnostic methods, its incidence has increased. So we reviewed our results from the past 30 years. Material and Method: We reviewed 27 cases surgically treated from March 1971 to March 2003. This investigation is designed to illustrate the peak age incidence, sex ratio, symptoms, anatomic location, radiologic imagings, associated diseases, operative methods, postoperative pathologic findings and postoperative complications. Result: The peak age incidence laid in the 1st to 3rd decade and the ratio of male and female was 1 : 1.5. The most common complaints were cough and dyspnea, but some had hemoptysis. There were 22 cases (81%) of Intrapulmonary bronchogenic cysts and 5 cases(19%) of mediastinal bronchogenic cysts. Thirteen cases (48.1%) showed cystic lesion in simple chest X-ray. Ten cases showed cystic lesion among 13 cases that had taken computed tomography. We found associated disease in 15cases (56%). The inflammatory diseases from infection were many in intrapulmonary bronchogenic cysts and especially, one case showed carcinosarcoma. Mitral regurgitation and Bronchial obstruction could be seen in mediastinal bronchogenic cysts. The 13 cases (48%) were managed by lobectomy, and cystectomy, pneumonectomy, and segemental resection were done in 7 cases (26%), 4 cases (15%), 3 cases (11%) respectively. Cystic contents were mucus in 9 cases, pus in 9 cases, blood in 2 cases, and carcinosarcoma in 1 case. Bronchotracheal communications were in 13 cases (48%). Five cases showed Postoperative complications, which were pneumothorax, empyema, bleeding. Postoperative death could not be found. Conclusion: Almost all patients had clinical symptoms. Severe complications could be associated with bronchogenic cysts. Recently, With the development of diagnostic methods, preoperatively accurate diagnosis is possible; therefore, invasive study has decreased. Bronchogenic cyst is a benign disease. However, because of its clinical symptoms, complications, and possibility of malignant change, immediate surgical treatment is needed.

• Sleep Medicine and Psychophysiology
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• v.8 no.1
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• pp.45-51
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• 2001

Objectives: The experience of traffic accident is a kind of the psychosocial stressors to person. The traffic accident-related patients may show the psychophysiologic hyperarousal. So we examined the differences of psychophysiologic response between patients with and without the memory of experienceing a traffic accident. Methods: Twenty-four traffic accident-related patients were divided into two groups according to ther memory of a traffic accident. In psychological assessment, levels of anxiety and depression were evaluated by State-Trait Anxiety Inventory, Beck's Depression Inventory, and Hamilton Rating Scales For Anxiety and Depression. Heart rate, electrodermal response (EDR), and electromyographic activity (EMG) were measured by biofeedback system, and systolic and diastolic blood pressure by automated vital sign monitor during baseline, task, and rest periods. We utilized script-driven imagery technique as a stressful task. The patients listened to the script describing their own traffic accident experience and were instructed to imagine the event during the task period. Statistically analytic data were obtained from the differences of psychological and psychophysiologic data between two groups. Results: The memory group did not show significantly higher EDR than the none memory group, but showed higher tendency during baseline, imagery, and rest periods. The memory group showed significantly lower EMG than the none memory group during rest period. However, there were no differences in other psychophysiologic reponses between the two groups. Conclusion: Our results showed that the memory group had higher tendency in autonomic arousal level such as electrodermal response than the none memory group. We suggest that physicians need to minimize repetitive imagery of traffic accident (reexperience), and decrease the autonomic hyperarousal in the treatment of traffic accident-related patients.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.5
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• pp.466-476
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• 2006

The objective of this study was to compare and analyze the acceptability and consumption attitude for soy foods between Korean and Canadian university students as young consumers. This survey was carried out by questionnaire and the subjects were n=516 in Korea and n=502 in Canada. Opinions for soy foods in terms of general knowledge were that soy foods are healthy (86.5% in Korean and 53.4% in Canadian) or neutral (11.6% in Korean and 42.8% in Canadian), dairy foods can be substituted by soy foods (51.9% in Korean and 41.8% in Canadian), and soy foods are not only for vegetarians and milk allergy Patients but also for ordinary People (94.2% in Korean and 87.6% in Canadian). In main sources of information about soy foods, the rate by commercials on TV, radio or magazine was the highest (58.0%) for Korean students and the rate by family or friend was the highest(35.7%) for Canadian students. In consumption attitude, all of Korean students have purchased soy foods but only 55.4% of Canadian students have purchased soy foods, and soymilk was remarkably recognized and consumed then soy beverage and margarine in order. 76.4% of Korean students and 65.1% of Canadian students think soy foods are general and popular and can purchase easily, otherwise, in terms of price, soy foods were expensively recognized as 'more expensive than dairy foods' was 59.1% (Korean) and 54.7% (Canadian), and 'similar to dairy foods' was 36.8% (Korean) and 39.9% (Canadian). Major reasons for the rare consumption were 'I am not interested in soy foods' in Korean students (27.3%) and 'I prefer dairy foods to soy foods' in Canadian students (51.7%). However, consumption of soy foods in both countries are very positive and it will be increased.

• Pediatric Infection and Vaccine
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• v.22 no.2
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• pp.106-112
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• 2015

Purpose: The long-term administration of antibiotics interferes with bacterial culture in the middle ear fluids (MEFs) of young children with otitis media with effusion (OME). The purpose of this study is to determine whether molecular diagnostics can be used for rapid and direct detection of the bacterial pathogen in culture-negative MEFs. Methods: The specificity and sensitivity of both polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP) to the lytA gene of Streptococcus pneumoniae were comparatively tested and then applied for pneumococcal detection in the clinical MEFs. Results: The detection limit of the PCR assay was approximately $10^4$ colony forming units (CFU), whereas that of LAMP was less than 10 CFU for the detection of S. pneumoniae. Both PCR and LAMP did not amplify nucleic acid at over $10^6$ CFU of H. influenzae or M. catarrhalis, both of which were irrelevant bacterial species. Of 22 culture-negative MEFs from children with OME, LAMP positivity was found in twelve MEFs (54.5%, 12/22), only three of which were PCR-positive (25%, 3/12). Our results showed that the ability of LAMP to detect pneumococcal DNA is over four times higher than that of PCR (P<0.01). Conclusions: As a high-resolution tool able to detect nucleic acid levels equivalent to <10 CFU of S. pneumoniae in MEFs without any cross-reaction with other pathogens, lytA -specific LAMP may be applied for diagnosing pneumococcus infection in OME as well as evaluating the impact of a pneumococcal conjugate vaccine against OME.

• Journal of KIISE:Information Networking
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• v.32 no.3
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• pp.279-290
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• 2005

Recently, as the serious damage caused by DDoS attacks increases, the rapid detection and the proper response mechanisms are urgent. However, existing security mechanisms do not effectively defend against these attacks, or the defense capability of some mechanisms is only limited to specific DDoS attacks. In this paper, we propose a detection architecture against DDoS attack using data mining technology that can classify the latest types of DDoS attack, and can detect the modification of existing attacks as well as the novel attacks. This architecture consists of a Misuse Detection Module modeling to classify the existing attacks, and an Anomaly Detection Module modeling to detect the novel attacks. And it utilizes the off-line generated models in order to detect the DDoS attack using the real-time traffic. We gathered the NetFlow data generated at an access router of our network in order to model the real network traffic and test it. The NetFlow provides the useful flow-based statistical information without tremendous preprocessing. Also, we mounted the well-known DDoS attack tools to gather the attack traffic. And then, our experimental results show that our approach can provide the outstanding performance against existing attacks, and provide the possibility of detection against the novel attack.

• Progress in Medical Physics
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• v.25 no.3
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• pp.143-150
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• 2014

In general radiotherapy, mega-voltage (MV) x-ray images are widely used as the unique method to verify radio-therapeutic fields. But, the image quality of MV images is much lower than that of kilo-voltage x-ray images due to scatter interactions. Since 1990s, studies for the scatter correction have performed with digital-based MV imaging systems. In this study, a novel method for the scatter correction is suggested using scatter to primary ratio (SPR), instead of conventional methods such as digital image processing or scatter kernel calculations. We measured two MV images with and without a solid water phantom describing a patient body with given imaging conditions, and calculated un-attenuated ratios. Then, we obtained SPR distributions for the scatter correction. For experimental validation, a line-pair (LP) phantom using several Al bars and a clinical pelvis MV image was used. As the result, scatter signals of the LP phantom image were successfully reduced so that original density distribution of the phantom was restored. Moreover, image contrast values increased after SPR correction at all ROIs of the clinical image. The mean value of increases was 48%. The SPR correction method suggested in this study has high reliability because it is based on actually measured data. Also, this method can be easily adopted in clinics without additional cost. We expected that the SPR correction can be an effective method to improve the quality of MV image guided radiotherapy.

• Journal of agricultural medicine and community health
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• v.13 no.1
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• pp.41-59
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• 1988

In many of the helminthic infections, diagnosis is accomplished by the demonstration of the eggs or, occasionally the adult worms or their parts. Diagnosis can be made by the identification of larval stage obtained from stool or surgically extracted materials too. However some kinds of parasitic disease can not be diagnosed by above mentioned procedure alone. Brain cysticercosis, ectopic paragonimiasis, Capillaria hepatica infection in liver is a good example. In such a case, immunologic method would be helpful for the decision of physician. In this paper, immunologic tools such as indirect hemagglutination test, indirect fluorescent antibody test, circumoval precipitation test, ELISA, western blot were applied for the diagnosis of Clonorchis sinenisis, Cysticercosis and C. hepatica a infection and their efficacy was evaluated. The results obtained were as follows ; 1) In the diagnosis of clonorchiasis, ELISA revealed sensitiveity of 83.3%, but cross reaction against antibody of Paragonimus westermani and Taenia species were observed. For the identification of cross reaction and species specific band of Ag-Ab reaction, western blot was applied. 59Kd relative molecular weight and 21Kd band were identified as a Clonorchis sinensis specific band. OD values of ELISA performed with sera of 18 months after praziquantel treatment decreased to half level compared to that of before treatment. Negative conversion rate of ELISA after 18 months of treatment was 60%. 2) In the diagnosis of cysticercosis, IFAT disclosed 95.8%(23/24) of sensitivity and reaction was most strongly occurred in inner membrane. ELISA revealed 90.0% (36/40) of sensitivity, but cross reaction was observed in both technique. In western blot, 91, 63 and 21Kd Mw bands were identified as a strongly positive band. Among them 63Kd band showed positive reaction against almost all sera of cysticercosis patient. 3) Circumoval precipitation, ELISA, IFAT, showed 85.0% of sensitivity in the diagnosis of C. hepatica infection in rat. The antigenic localities were inner membrane of sectioned egg antigen on the prectipitates around the mucoid plugs which were induced by circumoval precipitation reaction. Sera from rats infected with 2000eggs were collected periodically to observe the changing patterns of antibody titers by IFAT and ELISA, which showed that high titers were detected at weeks 3 and 5, then gradually declined through weeks 9until to negatively converted at weeks 13.