• Journal of the Korea institute for structural maintenance and inspection
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• v.28 no.2
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• pp.1-8
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• 2024

The expansion joint is installed to offset the expansion of the superstructure and must ensure sufficient gap during its service life. In detailed guideline of safety inspection and precise safety diagnosis for bridge, damage due to lack or excessive gap is specified, but there are insufficient standards for determining the abnormal behavior of superstructures. In this study, a data-based maintenance was proposed by continuously monitoring the expansion-gap data of the same expansion joint. A total of 2,756 data were collected from 689 expansion joint, taking into account the effects of season. We have developed a method to evaluate changes in the expansion joint-gap that can analyze the thermal movement through four or more data at the same location, and classified the factors that affect the superstructure behavior and analyze the influence of each factor through deep learning and explainable artificial intelligence(AI). Abnormal behavior of the superstructure was classified into narrowing and functional failure through the expansion joint-gap evaluation graph. The influence factor analysis using deep learning and explainable AI is considered to be reliable because the results can be explained by the existing expansion gap calculation formula and bridge design.

• Korean Journal of Agricultural and Forest Meteorology
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• v.26 no.1
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• pp.63-74
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• 2024

In agriculture, frost can be devastating, which is why observation and forecasting are so important. According to a recent report analyzing frost observation data from the Korea Meteorological Administration, despite global warming due to climate change, the late frost date in spring has not been accelerated, and the frequency of frost has not decreased. Therefore, it is important to automate and continuously operate frost observation in risk areas to prevent agricultural frost damage. In the existing frost observation using leaf wetness sensors, there is a problem that the reference voltage value fluctuates over a long period of time due to contamination of the observation sensor or changes in the humidity of the surrounding environment. In this study, a datalogger program was implemented to automatically solve these problems. The established frost observation system can stably and automatically accumulate time-resolved observation data over a long period of time. This data can be utilized in the future for the development of frost diagnosis models using machine learning methods and the production of frost occurrence prediction information for surrounding areas.

• Journal of the Korean Society of Radiology
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• v.82 no.6
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• pp.1581-1588
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• 2021

Electronic cigarette (e-cigarette) or vaping product use-associated lung injury (EVALI) has emerged as a social issue as e-cigarette use is rapidly increasing worldwide and is related to many deaths in the United States. To our knowledge, this is the first case report of EVALI in South Korea of a 24-year-old man with acute respiratory symptoms and a history of e-cigarette use. Chest CT revealed diffuse bilateral ground-glass opacities with subpleural sparing, airspace consolidation, and centrilobular micronodules as typical patterns of EVALI with organizing pneumonia and diffuse alveolar damage. Infection was excluded with meticulous laboratory examinations, and the patients' illnesses were not attributed to other causes. EVALI was diagnosed by meeting the diagnostic criteria with consistent clinico-radiologic findings through a multidisciplinary approach. Radiologists should have good knowledge of EVALI radiologic findings and play a cardinal role in the proper diagnosis and management of EVALI.

• Korean Journal of Remote Sensing
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• v.40 no.3
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• pp.275-284
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• 2024

Monitoring crop growth changes and water content is crucial in the agricultural sector. This study utilized drones equipped with Short Wavelength Infrared (SWIR) sensors, sensitive to moisture changes, to observe soybeans' growth and water content variations. We confirmed that as soybeans grow more vigorously, their water content increases and differences in irrigation levels lead to decreases in vegetation and moisture indices. This suggests that waterlogging slows down soybean growth and reduces water content, highlighting the importance of detailed monitoring of vegetation and moisture indices at different growth stages to enhance crop productivity and minimize damage from waterlogging. Such monitoring could also preemptively detect and prevent the adverse effects of moisture changes, such as droughts, on crop growth. By demonstrating the potential for early diagnosis of moisture stress using drone-based SWIR sensors, this research suggests improvements in the efficiency of large-scale crop management and increases in yield, contributing to agricultural production.

• Tuberculosis and Respiratory Diseases
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• v.44 no.5
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• pp.1083-1093
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• 1997

Background : So far, there have been numerous reports on organ damage due to cryptococcosis, however, cases of lung localization have been infrequently reported. Recently pulmonary cryptococcosis has been reported more frequently than before due to enhanced diagnostic techniques and increased underlying diseases. Method : The author, therefore, analyzed the clinical manifestations of 5 cryptococcosis cases that we experienced at Hanyang University Hospital from 1985 to 1996 and 9 cases reported in Korea from 1984 and 1996 retrospectively. The following results were obtained. Results : Cryptococcosis occurred frequently over sixth decade and the male to female ratio was 3.6 : 1. Underlying diseases included acute rejection after kidney transplantation, rheumatoid arthritis, autoimmune hepatitis, diabetes mellitus and state of bilateral adrenalectomy. Remaining 8 cases had no evidence of an underlying disease. Because the symptoms were subacute & nonspecific, and not improved by conventional antibiotics, 6 patients of 14 pulmonary cryptococcosis patients were treated as pulmonary tuberculosis before correct diagnosis was made. There were three asymptomatic cases. According to the results of CXR, solitary alveolar consolidation was the most common finding(8 cases) followed by diffuse infiltration(5 cases). It also showed pleural effusion, hilar lymphadenopathy and cavity formation that was rarely reported in world literature. The diagnasis was made through fine needle aspiration biopsy in 10 cases, open thoracotomy in 2 cases, transbronchial lung biopsy in 1 case. and thoracentesis with pleural biopsy in 1 case. Only one case showed positive result in sputum stain and culture, serum latex agglutination test for cryptococcus neoformans. Treatment modalities were various such as fluconazole, amphotericin B, flucytosine, ketoconazole, surgery and it's combination. After 1990 year, there was a trend that fluconazole or ketoconazole are more used than other therapeutic modalities. Conclusion : Because the symptoms are subacute & nonspecific and not improved by conventional antibiotics, pulmonary cryptococcosis is likely to misdiagnosis as pulmonary tuberculosis in Korea. Because the diagnosic yield of sputum stain, culture and serologic test for pulmonary cryptococcosis is low, histologic diagnosis is need in most pulmonary cryptococcosis.

• Clinical and Experimental Pediatrics
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• v.48 no.9
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• pp.998-1003
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• 2005

Purpose : We evaluated the occurrence of renal scarring in children with unilateral vesicoureteral reflux(VUR), and the relationships between renal scar formation and risk factors such as VUR, duration of fever, acute-phase reactant, age, and sex. Methods : We retrospectively analyzed the data of 35 children newly diagnosed with unilateral vesicoureteral reflux after urinary tract infection(UTI) in Wallace Memorial Baptist Hospital between January 1996 and December 2004. Ultrasonography, Erythrocyte sedimentation rate(ESR), and C-reactive protein(CRP) were performed initially. Voiding cystourethrography(VCUG) was performed 1 to 3 weeks after treatment with UTI. $^{99m}Tc$-dimercaptosuccinic acid(DMSA) scan was performed 4 to 6 months after treatment. Results : Scintigraphic renal damage was present in 29 percent of the refluxing and in 3 percent of the nonrefluxing kidneys(P<0.05). The severity of VUR was significantly correlated with renal scar formation(P<0.05). The duration of fever before treatmen($5.0{\pm}1.3$ vs $2.6{\pm}1.3$) and prolonged fever of over 5 days were significantly different between renal scar group and non-renal scar group(P<0.05). ESR($56.3{\pm}23.8$ vs $27.9{\pm}18.1mm/hr$, P<0.05) and CRP($12.8{\pm}7.3$ vs $3.9{\pm}3.8mg/dL$, P<0.05) at the diagnosis of UTI in the renal scar group were higher, compared to those of the non-renal scar group. There were no significant differences in age and sex between the two groups. Conclusion : The presence and grade of VUR, the duration of fever before treatment, prolonged fever over 5 days, ESR, and CRP were risk factors for renal scarring, irrespective of age and sex. Diagnosis and management of VUR, in children with UTI, is important to prevent renal scars.

• Sleep Medicine and Psychophysiology
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• v.3 no.1
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• pp.85-95
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• 1996

Obstructive sleep apnea syndrome(OSAS) in childhood is unique and different n-om that in adulthood in several aspects, including pathophysiology, clinical features, diagnostic criteria, complications, management, and prognosis. Characteristic features of childhood OSAS in comparison with the adult form are the variety of severe complications such as developmental delay, more prominent behavioral and cognitive impairments, vivid cardiovascular symptoms, and increased death risk, warranting a special attention to the possible diagnosis of OSAS in children who snore. However, the childhood OSAS is often neglected and unrecognized. We, therefore, report a case of very severe OSAS in a 5-year-old boy who was sucessfully treated with continuous positive airway pressure(CPAP) treatment. Interestingly, the patient was comor-bid with the attention deficit hyperactivity disorder. Prior to the initial visit to us, adenotonsillectomy had been done at the age of 4 with no significant improvement of apneic symptoms and heavy snoring. On the initial diagnostic procedures, marked degree of snoring was audible even in the daytime wake state and the patient was observed to be very hyperactive. Increased pulmonary vascularity with borderline cardiomegaly was noted on chest X-ray. The baseline polysomnography revealed that the patient was very sleep-apneic and snored very heavily, with the respiratory disturbance index(RDI) of 46.9 per hour of sleep, the mean SaO2 of 78.8%, and the lowest SaO2 of 40.0%(the lowest detectable oxygen level by the applied oxymeter). The second night polysomnography was done for CPAP titration and the optimal pressure turned out to be $8.0\;cmH_2O$. The applied CPAP treatment was well tolerated by the patient and was found to be very effective in alleviating heavy snoring and severe repetitive sleep apneas. After 18 months of the CPAP treatment, the patient was followed up with nocturnal polysomnography(baseline and CPAP nights) and clinical examination. Sleep apneas were still present without CPAP on the baseline night. However, the severity of OSAS was significantly decreased(RDI of 15.7, mean SaO2 of 96.2%, and the lowest SaO2 of 83.0%), compared to the initial polysomnographic findings before initiation of long-term CPAP treatment. Wechsler intelligence tests done before and after the CPAP treatment were compared with each other and surprising improvement of intelligence(total 9 points, performance 16 points) was noted. Clinically he was found to be markedly improved in his attention deficit hyperactive behavior after CPAP treatment, but with minimal change of TOVA(test of variables of attention) scores except conversion of reaction time score into normal range. On the chest X-ray taken after 18 months of CPAP application, the initial cardiopulmonary abnormalities were not found at all. We found that the CPAP treatment in a young child is very effective, safe, and well-tolerated and also improves the co-morbid attention deficit hyperactive symptoms. Overall, the growth and development of the child has been facilitated with the long-term use of CPAP. Cardiovascular complications induced by OSAS have been also normalized with CPAP treatment. We suggest that early diagnosis and active treatment intervention of OSAS in children are crucial in preventing and ameliorating possible serious complications caused by repetitive sleep apneas and consequent hypoxic damage during sleep.

• Journal of Chest Surgery
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• v.34 no.6
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• pp.477-484
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• 2001

Background: Initial symptoms for esophageal perforation have not been clarified, but when there is no early diagnosis and proper treatment to follow immediately after the diagnosis, it is fatal for the patients. Therefore, this study attempted to discover the factors that influence the prognosis of esophageal perforation to contribute to the improvement of the treatment result. Material and Method: The subjects of this study are 32 patients who came to the hospital with esophageal perforation from October, 1984 to June, 2000. This study examined the items for clinical observation such as patients' sex, age, cause of the perforation, perforation site, the time spent until the beginning of the treatment, symptoms caused by the perforation and its complication, and treatment methods. This study tried to find out the relationship between the survival of patients and each item. Result: There were 24 male and 8 female patients and their mean age was 49.7+16.4. For the causes of perforation, there were 14 cases(43%) of iatrogenic perforation, which ranked first, caused by the medical instrument operation and surgical damage. As for the perforation sites, thoracic esophagus was the most common site(26 cases of 81.2%) and chest pain was the most frequent symptom. The complication caused by esophageal perforation showed the highest cases in the order of mediastinitis, empyema, sepsis and peritonitis. After the treatment, there were 23 cases of survival and 9 cases of mortality. The total mortality rate was 28.1% and the main causes of mortality were sepsis and acute respiratory distress syndrome(ARDS). As for the treatment, 8 cases(25.0%) treated the perforation successfully using conservative treatment only. As for the surgical treatment, there were 5 cases(15.6%) of cervical drainage, 7 cases (21.8%) of primary repair and 12 cases(37.5%) of esophageal reconstruction after performing an exclusion-diversion. There were 18 cases(56.2%) of complete treatment of esophageal perforation at its initial treatment and in 14 cases(43.8%) of treatment failure at its initial treatment, patients were completely cured in the next treatment stage or died during the treatment. The cases of perforation in thoracic esophagus, complication into severe mediastinitis or sepsis and the cases of failure at initial treatment showed a statistically significant mortality rate (p<0.05).

• 보존과학연구
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• s.34
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• pp.64-81
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• 2013

It is not easy to define the priority criteria of the need of conservation treatment for stone cultural heritage, although many of them have been treated and restored over the past decade. This study approached the correlation between damage grade and the need of conservation treatment based on damage diagnosis of stone cultural heritage carried out from 2001 to 2005. The number of Third-graded (from First to Fifth-grade) stone heritage in deterioration was the highest among state-designated stone cultural heritage. The Fourth-graded stone cultural heritage (143 in total) was mostly influenced by high physiochemical deterioration, whereas the Fifth-graded ones (61 in total) was dominantly affected by biological colonization. It was estimated that total 211 stone cultural heritage were treated for conservation and restoration from 2002 to 2011. They were usually cleaned (total 134, 26.1%), joined and consolidated, and maintenance works as shelter construction, drainage installation and surrounding cleaning were carried out for some of them. The number of conservation intervention increased with the high deterioration grade, and the case number of metamorphic and sedimentary rocks. By age, the stone cultural heritage in Three-kingdom Period were treated the most, and other heritage in Unified Shilla, Goryeo and Joseon showed an approximate ratio. The stone cultural heritage fallen in the fifth-grade in deterioration demonstrated the highest ratio, approximately 80% of conservation intervention. These results can be used as preliminary data to define the emergency criteria for conservation intervention policy.

• Childhood Kidney Diseases
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• v.1 no.1
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• pp.46-52
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• 1997

Urinary tract infection (UTI) in children has been known to be a cause of renal damage, leading to scar formation, hypertension and renal failure. And vesico-ureteral reflex (VUR), frequently accompanying UTI in young children, has been incriminated as the main factor causing scar formation. This retrospective study has been undertaken to see the relationship among UTI, VUR and renal scar formation. Study population consisted of 291 children (boy 134, girl 42) with UTI, who have been admitted to the Pediatric Department of Kyungpook University Hospital during 6 1/2 year period from January 1990 to June 1996. VUR was diagnosed by VCUG and renal scar by ultrasonogram, DMSA scan (or DMSA SPECT) and IVP. The following result were obtained. Sexual difference showed male predominance (male to female, 134:42) below 1 year of age, and female predominance (male to female, 11:35) over 5 years of age were rioted. VUR has been found in 64 children (22%) and the degree of reflux, classfied by the method proposed by 'International Reflux Study in Children', were as follows ; Grade I : 4.0%, Grade II : 3.0%, Grade III : 2.7%, Grade IV : 5.8% and Grade V : 6.2%. There was no sexual difference E.coli was the most predominant infecting agent occurring in 167 children (57%), and end-stage renal failure was diagnosed at the time of first admission in 5 children with Grade V VUR. Renal scar has been noted in 49 out of 582 kidneys (8.4%), and the incidence of scar foramation according to the degree of VUR were as follow ; Grade 0 (No reflux) : 1.2%, Grade I : 6.7%, Grade II 27.3%, Grade III 29.4%, Grade IV : 57.1%, and Grade V : 100%. In summary, present study shows that renal scar formation in UTI has close correlation with the severity of VUR occurring more frequently in severe reflux, so that early diagnosis and proper treatment of UTI and VUR is of paramount importance in preventing renal damage in children with UTI.