• Nuclear Engineering and Technology
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• v.40 no.6
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• pp.451-458
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• 2008

After more than 10 years construction, KSTAR (Korea Superconducting Tokamak Advanced Research) had finally completed its assembly in June 2007, and then achieved the goal of first-plasma in July 2008 through the four month's commissioning. KSTAR was constructed with fully superconducting magnets with material of $Nb_3Sn$ and NbTi, and their operation temperatures are maintained below 4.5K by the help of Helium Refrigerator System. During the first-plasma operation, plasmas of maximum current of 133kA and maximum pulse width of 865ms were obtained. The KSTAR Integrated Control System (KICS) has successfully fulfilled its missions of surveillance, device operation, machine protection interlock, and data acquisition and management. These and more were all KSTAR commissioning requirements. For reliable and safe operation of KSTAR, 17 local control systems were developed. Those systems must be integrated into the logically single control system, and operate regardless of their platforms and location installed. In order to meet these requirements, KICS was developed as a network-based distributed system and adopted a new framework, named as EPICS (Experimental Physics and Industrial Control System). Also, KICS has some features in KSTAR operation. It performs not only 24 hour continuous plant operation, but the shot-based real-time feedback control by exchanging the initiatives of operation between a central controller and a plasma control system in accordance with the operation sequence. For the diagnosis and analysis of plasma, 11 types of diagnostic system were implemented in KSTAR, and the acquired data from them were archived using MDSpius (Model Driven System), which is widely used in data management of fusion control systems. This paper will cover the design and implementation of the KSTAR integrated control system and the data management and visualization systems. Commissioning results will be introduced in brief.

• Journal of the Korean Society for Railway
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• v.20 no.2
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• pp.203-209
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• 2017

Research on condition monitoring and diagnosis of power facilities has been conducted to improve the safety and reliability of electric power supply. Although insulation diagnostic techniques for unit equipment such as gas-insulated switchgears and transformers have been developed rapidly, studies on monitoring of cables have only included aspects such as whether defects exist and partial discharge (PD) detection; other characteristics and features have not been discussed. Therefore, this paper dealt with PD characteristics against void sizes and positions, and with defect localization in XLPE cable. Four types of defects with different sizes and positions were simulated and PD pulses were detected using a high frequency current transformer (HFCT) with a frequency range of 150kHz~30MHz. The results showed that the apparent charge increased when the defect was adjacent to the conductor; the pulse count in the negative half of the applied voltage was about 20% higher than that in the positive half. In addition, the defect location was calculated by time-domain reflectometry (TDR) method, it was revealed that the defect could be localized with an error of less than1m in a 50m cable.

• Journal of Veterinary Clinics
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• v.22 no.2
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• pp.148-152
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• 2005

An intact female, 5-year-old, Pekingese, weighing 3.5kg with a history of a palpated abdominal mass was referred to Veterinary Medical Teaching Hospital, Seoul National University. In laboratory examination, there were no remarkable abnormalities. Radiographic findings included a left mid-abdominal mass with ill-defined margin, serosal detail loss of peritoneal space, non-uniform opacity of retroperitoneal space, and a radiopaque cystic calculus. On abdominal ultrasonography, a heterogeneous parenchymal mass with irregular contour in the left renal region was found. Computed tomographic findings showed a tumor embolus within the caudal vena cava and an invasion into mesentery, small bowel loops, spleen and pancreas around the large left renal mass. Unilateral nephroureterectomy was performed. Histopathologic examination of the resected mass confirmed the diagnosis of renal cell carcinoma. The dog died one day after surgery. Although ultrasonography could give diagnostic information about mass characteristics, computed tomography (CT) can provide key imaging features of mass characteristics.

• Clinical and Experimental Pediatrics
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• v.45 no.5
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• pp.603-608
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• 2002

Purpose : Pertussis is a highly communicable infectious disease in children with high mortality, especially in young infants. The incidence of pertussis in South Korea has decreased to about 10 cases a year in late '90s. Doubting previously reported incidences of pertussis, we designed this study to establish exact epidemiology and a diagnostic basis of pertussis. Methods : From Mar. 2000 to Mar. 2001, polymerase chain reaction(PCR) and cultures of nasopharyngeal aspirates were taken from 49 patients who were clinically suspected of pertussis in Kangdong Sacred Heart Hospital. Results : Among 49 patients suspected of pertussis, 10 cases showed positive results by PCR method. Four out of those 10 cases were positive in culture. The peak outbreak was noticed in the spring(Mar.-May) and the autumn(Sep.-Nov.). The mean age of the patients was 3.6 months. Eight of the 10 cases which were PCR positive results proved not to be immunized against pertussis. Conclusion : Most of the pertussis patients in our study were diagnosed as bronchiolitis, pneumonia or bronchitis at the beginning of the disease and only a few patients showed typical clinical manifestations of pertussis, including whooping. When the above results are taken together, we suggest the possibility that the actual prevalence of pertussis in South Korea might be higher than that of previous reports. The importance of pertussis screen tests should be emphasized in children with severe coughs.

• Korean Journal of Plant Taxonomy
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• v.41 no.4
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• pp.345-352
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• 2011

The morphological characters of Scrophularia kakudensis Franch. and its relatives were examined. The major features of S. kakudensis were determined to resolve the taxonomic confusion with the closely related taxa of S. kakudensis var. microphylla, S. pilosa and S. cephalantha. S. kakudensis is characterized by its flowering in Jul. to Sep., the node numbers on a stem, the size of the leaves, the development of inflorescences and the presence of glandular trichomes on its stems and leaves. S. cephalantha is distinct from S. kakudensis by the earlier flowering season, fewer node numbers on a stem, and fewer numbers of flowers on shorter rachis. Smaller sizes of S. kakudensis var. microphylla, considered to be a problematic character previously, are stable and distinctive from other taxa in the natural habitats of the multiple populations investigated in the study. Therefore, the taxon should remain as a variety of S. kakudensis. An examination of the diagnostic characteristics of S. pilosa, such as its inflorescence type and the presence of a stem with pubescence, does not provide sufficient distinction from S. kakudensis. A type specimen and habitat survey also support the merging of the two taxa. S. pilosa should be treated as a synonym of S. kakudensis, because it is considered to be a misidentification of S. kakudensis.

• Journal of Gastric Cancer
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• v.5 no.1
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• pp.47-51
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• 2005

Eosinophilic gastroenteritis is a rare clinicopathologic entity of unknown etiology with a variety of digestive symptoms. The pathogenesis is poorly understood. Diagnostic criteria include demonstration of eosinophilic infiltration of the affected bowel wall, lack of evidence of extraintestinal disease, and exclusion of various disorders that could mimic similar conditions. The disease might involve any area of the gastrointestinal tract from the esophagus to the rectum, but the stomach and the proximal small bowel are most commonly affected. The clinical features depend on which layer and site are involved. We report the case of a 59-year-old male patient with a 3-week history of post-prandial vomiting with malnutrition and weight loss. An abdominopelvic CT showed a gastric outlet obstruction with diffuse wall thickening, as with linitis plastica. Three gastrofiberscopic biopsies showed chronic gastritis. We carried out a radical total gastrectomy with D2 lymph node dissection. The pathologic report revealed a mural type eosinophilic gastritis with a marked hypertrophic scar formation at the proper muscle layer. We report this case with a brief review of the literature. (J Korean Gastric Cancer Assoc 2005;5:47-51)

• Biomedical Science Letters
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• v.5 no.2
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• pp.191-200
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• 1999

In recent years continuously increasing number of tuberculosis (TB) cases due to the emergence of strains with multidrug resistance and AIDS is a significant global health problem. Therefore, more rapid and reliable diagnosis of TB may be one of the most urgent needs in efforts to eradicate the disease. The present study was designed to compare and assess the diagnostic values and efficiencies between the conventional methods (X-ray, AFB stain and culture) and PCR for pulmonary TB on 171 cases. Chest X-ray finding and clinical features revealed that 39 (22.8%) of 171 sputum specimens were pulmonary TB cases. The statistical data were taken on the basis of the definitive diagnosis: In X-ray, overall sensitivity, specificity, efficiency and false positive and false negative incidence was respectively 69.2%, 87.1％, 83.0%, 12.9%, and 30.8％； 79.5%, 95.5%, 91.8%,4.6％ and 20.5％ in AFB-stain; 56.4%, 99.2%,89.5%, 0.8% and 43.6% in culture; 82.1%, 96.2%, 93.0%, 3.8% and 17.9% in PCR. PCR got a highest sensitivity and efficiency as well as a lowest false negative incidence. Culture had a highest specificity with a lowest false positive incidence. These results imply that PCR assay is fast, sensitive and efficient method for diagnosis of pulmonary TB. However, combined use of the conventional methods with thorough quality control may offer more opportunities for detecting Mycobacterium tuberculosis and diagnosting TB although they have some limits.

• Investigative Magnetic Resonance Imaging
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• v.19 no.4
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• pp.231-236
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• 2015

A 17-year-old girl presented with complaints of headache and decreasing vision of one month's duration, without any history of fever, weight loss, or any evidence of an immuno-compromised state. Her neurological examination was normal, except for papilledema. Laboratory investigations were within normal limits, except for a slightly increased Erythrocyte Sedimentation Rate (ESR). Non-contrast computerized tomography of her head revealed complex mass in left frontal lobe with a concentric, slightly hyperdense, thickened wall, and moderate perilesional edema with mass effect. Differential diagnoses considered in this case were pilocytic astrocytoma, metastasis and abscess. Magnetic resonance imaging (MRI) obtained in 3.0 Tesla (3.0T) scanner revealed a lobulated outline cystic mass in the left frontal lobe with two concentric layers of T2 hypointense wall, with T2 hyperintensity between the concentric ring. Moderate perilesional edema and mass effect were seen. Post gadolinium study showed a markedly enhancing irregular wall with some enhancing nodular solid component. No restricted diffusion was seen in this mass in diffusion weighted imaging (DWI). Magnetic resonance spectroscopy (MRS) showed increased lactate and lipid peaks in the central part of this mass, although some areas at the wall and perilesional T2 hyperintensity showed an increased choline peak without significant decrease in N-acetylaspartate (NAA) level. Arterial spin labelling (ASL) and dynamic susceptibility contrast (DSC) enhanced perfusion study showed decrease in relative cerebral blood volume at this region. These features in MRI were suggestive of brain abscess. The patient underwent craniotomy with excision of a grayish nodular lesion. Abundant acid fast bacilli (AFB) in acid fast staining, and epithelioid cell granulomas, caseation necrosis and Langhans giant cells in histopathology, were conclusive of tubercular abscess. Tubercular brain abscess is a rare manifestation that simulates malignancy and cause diagnostic dilemma. MRI along with MRS and magnetic resonance perfusion studies, are powerful tools to differentiate lesions in such equivocal cases.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.11
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• pp.221-228
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• 2014

The color and shape of the tongue reflect the physiological and clinico-pathological condition of the body. Recently, various tongue image acquisition devices have been developed for accurate diagnosis based on quantitative and objective tongue features. Since a color information is essential for tongue diagnosis, the performance of an illuminator is very important for the tongue image acquisition device. In this study, we developed an indirect illumination, which is possible to improve a homogeneity of light intensities on the tongue surface, and evaluated its performances. In order to realize the indirect illumination (II), a semi-ellipsoidal solid structure (SESS) for the light reflex was located in the system, and two high-brightness white LEDs were placed for illuminating the areas under frontal camera in the SESS. The tongue surface was illuminated by reflected light from the SESS. The light homogeneity induced by three different illuminations including the II was evaluated by calculating coefficient of variation (CV) of illuminance of five regions. The II showed less than 0.01 of CV and the direct illumination (DI) and the direct illumination with a light diffusion plate (DILDP) showed 0.16 and 0.13, respectively. The reflexed pixel ratios of tongue phantom images show 5.76%, 4.22%, 1.79% for the DI, the DILDP and the II, respectively. The homogeneity of a tongue phantom was evaluated by calculating CV of mean pixel values of six different tongue regions, and showed less than 0.06 in the II. If the II technique apply to tongue diagnosis system, it is expected to improve diagnostic accuracy in clinic.

• Tuberculosis and Respiratory Diseases
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• v.45 no.2
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• pp.429-436
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• 1998

Approximately 100 drugs have been reported to affect the lungs adversely. Among these, pulmonary toxicity caused by antieneoplastic agent. is being recognized more frequently. Cyclophosphamide is an immunosuppressive alkylating agent used for the treatment of a wide variety of malignant and nonmalignant diseases. The incidence of pulmonary toxicity is probably less than 1 percent The first case was reported in 1967. Since then, more than 20 well-documented cases of pulmonary toxicity associated with cyclophosphamide have been reported in the literature. In Korea, three patients were identified with cyclophosphamide-induced lung disease. The typical features of toxicity include dyspnea, fever, cough, new parenchymal infiltrates, gas exchangs abnormalities on pulmonary function tests, and pleural thickening on chest roentgenogram. The best approach to management is early diagnosis, discontinuation of the offending drug and administration of corticosteroid therapy. Recently, we experienced a case of diffuse alveolar damage induced by cyclophosphamide. The patient presented with early-onset pulmonary toxicity and died of repiratory failure despite early use of corticosteroid.