• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.11a
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• pp.5-8
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• 2006

This study investigates the field application, Songdo the # 1st WORLD, on zero-crack construction of the fundamental mass concrete using double bubble sheets and applying low heat mixture. Experimental results of hydration heat analysis showed that crack modulus of concrete incorporating 20% of blast furnace slag cement was 1.0 in 120 hours, representing 50% probability of crack occurrence, thus requiring additional measures. As for a curing method, a specimen insulating two layers of vinyl chloride+double bubble sheets exhibited only $16.5^{\circ}C$ difference between upper and lower sections, and it also showed favorable workability as well as competitive economic side. Therefore it was determined to use it for curing method in this field. For the curing results of practical field, using 2 layers of vinyl chloride+double bubble sheets and applying low heat mixture on the fundamental mass concrete in 3A residential building exhibited less than only $15^{\circ}C$ difference between surface and center section of that in 5 days elapse and less than $20^{\circ}C$ in 9 days. This means that the crack by hydration heat was prevented, and other fields structures also resisted the plastic shrinkage by insulating the vinyl, sinking crack by second temping, even drying shrinkage by the mixture of low unit water. Therefore the crack on the placement has not been found so far, since the construction was started before 6 month.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.528-537
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• 1996

Qualify changes of microwave-reheated cooked rice aseptic-packaged with different lid materials and oxygen absorbers were determined during storage at $20^{\circ}C,\;30^{\circ}C$ and $40^{\circ}C$. Springiness cohesiveness and adhesiveness increased as storage temperature increased, while gumminess and hardness decreased. Lid materials oxygen absorbers, and storage temperatures showed no significant effect on the textural properties of cooked rice after microwave reheating. Degree of gelatinization was increased as storage temperature increased and was restored after microwave reheating. Scanning electron micrograph showed that the surface of cooked rice became rough and hollowed after microwave reheating for 1.5 min, indicating starch was regelatinized, while there was no difference with respect to lid materials. Photomicrographs of the cross-section of aseptic-Packaged cooked rice showed that a compact and solid structure increased and retrogradation occured in starch as storage temperature decreased, while a compact and solid structure was decreased and starch was regelatinized after microwave reheating.

• Journal of the Society of Naval Architects of Korea
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• v.39 no.1
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• pp.90-99
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• 2002

The prediction of stress intensity factor(SIF) is one of the most important factors to analyse the propagation behavior of cracks in hull structural members. Up to now, however, simplified prediction method of SIF has not yet been established for the cracks experienced in large complex structures. As a first step to predict crack propagation behavior in a ship structure with very large structural redundancies, simplified SIF prediction formulas for various crack shapes were derived based on the results of the stress analysis under a non-crack condition in this study. The adequacy of the proposed method was then verified in comparison with other experimental and analysis results.

• Pediatric Infection and Vaccine
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• v.8 no.2
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• pp.191-198
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• 2001

Purpose : The purpose of this study was to investigate clinical features of hospitalized infants 28~90 days of age with fever without source and to analyze those of young febrile infants using risk criteria for serious bacterial infection. Methods : The clinical features of 131 infants 28~90 days of age admitted to the Ulsan Dong-Kang General Hospital Pediatric Department because of fever(temperature ${\geq}38^{\circ}C$ rectally) without source, from January 2000 to December 2000, were investigated by retrospective chart review. The clinical features of 131 febrile infants were analyzed using Rochester criteria. Results : Among 131 cases, there were 60 cases(45.8%) of urinary tract infection, 33 cases (25.2%) of aseptic meningitis, 2 cases(1.5%) of bacteremia and 36 cases(27.5%) of no specific diagnosis. Among 131 cases, there were 57 cases(43.5%) in low risk group and 74 cases(56.5%) in not low risk one by Rochester criteria. A significant difference in the incidence of urinary tract infection, aseptic meningitis and no specific diagnosis was not found between both groups. Male to female ratio was 1.8 : 1. Sex ratio between both groups was not significantly different. Most febrile infant were noted in spring(35.1%) and the summer(36.7%). The peak incidence of aseptic meningitis was noted in May and June. The fever subsided mostly within 48~72 hours after administering antimicrobial agents(61.8~83.2%). A significant difference in duration of fever after administering antimicrobial agents was not found between both groups. Conclusion : A selected group of low risk infants 28~90 days of age with fever without source can be managed as outpatients provided that a thorough initial evaluation is performed, that parents can reliably monitor their infant closely at home and that careful follow up can be assured. Because bag collected specimens were more likely to yield indeterminate urine culture result, a suprapubic or catheter obtained urine specimen for culture is a necessary part of the evaluation of all febrile infants 28~90 days of age. The further prospective study on evaluation and management of young febrile infant should be performed in our hospital.

• Pediatric Infection and Vaccine
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• v.8 no.1
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• pp.94-100
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• 2001

Purpose : Enterovirus is a common cause of aseptic meningitis and nonspecific febrile illness in young children. During the summer and fall months, enterovirus-infected young children are frequently admitted and evaluated to rule out bacterial sepsis and/or meningitis. The purpose of this study was to evaluate the relationship between nonpolio enterovirus infection and febrile illness in infants under 3 months of age during the summer, fall months by using a stool culture to identify the presence of enterovirus. Methods : Patients included febrile infants under 3 months of age admitted to Masan Fatima Hospital for sepsis evaluation from May 1999 to September 1999. Cultures were performed from stool and Cerebrospinal fluid samples and then were tested for enterovirus infection. Viral isolation and serotype identification were performed by cell culture and immunofluorescent testing. Enteroviruses not typed by immunofluorescent testing were confirmed by reverse transcription-polymerase chain reaction. Results : A total of 44 febrile infants were enrolled; of those, 20(45%) were positive for enterovirus. Two enterovirus culture-positive infants had concomitant urinary tract infection and one had Kawasaki disease. All infants infected with an enterovirus recovered without complications. Serotype of 20 enteroviruses were isolated from stool, 3 of echovirus type 9, 1 of echovirus type 11, 1 Coxsachievirus type B4, 15 of untyped enteroviruses. One untyped enterovirus was isolated in the CSF. Conclusion : Nonpolio enterovirus infections are associated with nonspecific febrile illnesses in infants under 3 months of age.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.4
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• pp.496-502
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• 2017

The purpose of this study is to investigate the applicability of surface-wave techniques for the evaluation of the crack-repairing performance of an epoxy injection method in concrete. In this study, box-shaped concrete specimens with four different crack depths were made with identical mix proportions. The specimens with different crack depths were completely repaired using the same epoxy injection method. The spectral energy transmission ratio of surface waves is used as an index to differentiate the effects of crack depth and crack-repairing performance. The decrease of spectral energy transmission ratio in accordance with the increase of crack depth was identified before repairing. Furthermore, the spectral energy transmission ratio increased after the crack-repairing process in all specimens. The spectral energy transmission ratio is considered as a great indicator for estimating the crack-repairing performance of the epoxy injection method; the ratio was recovered up to almost 95% of the uncracked condition.

• Pediatric Infection and Vaccine
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• v.10 no.2
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• pp.215-222
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• 2003

Purpose : This study was to analyze serious bacterial infections in infants younger than three months of age and to review the direction of treatments for these patients. Methods : 378 febrile infants with a rectal temperature ${\geq}38.0^{\circ}C$ visited from Jan. 2001 through Dec. 2002 were retrospectively studied. Infants with the following criteria belonged to the low risk group. WBC $5,000{\sim}15,000/mm^3$, WBC negative in urine stick test and negative for nitirite test, CSF WBC < $10/mm^3$ and negative in CSF gram stain, negative chest X-ray, stool WBC <5/HFP(high power field), and focal infection. If any of the above criteria were not met, they belonged to the high risk group. SBI was defined as a positive culture of urine, blood or CSF. SI was defined as aseptic meningitis or pneumonia including above laboratory tests of SBI. SBI patients were separately compared with two groups, high risk and low risk. Results : Of the 378 infants that were tested 216(57.1%) were in the high risk group and 162(42.9%) in the low risk group. Among 105 SBI(27.8%) and 172 SI(45.5%), there were 98 urinary tract infection(25.2%), 10 bacteremia(2.6%), 2 bacterial meningitis(0.6%), and 77 aseptic meningitis(22.8%). There were 76 SBI(35.2%) from the high risk group and 29 SBI(17.9%) from the low risk group identified. The results of the sensitivity(72.4%), the specificity(48.7%), the negative predictive value(82.1%) and the positive predictive value (35.2%) were calculated. Conclusion : Even though the probability of SBI in the low risk group is insignificant, it should still be considered in febrile infants younger than 3 months of age. I believe the CSF study is necessary because of the moderate high incidence of abnormal finding in our study.

• Clinical and Experimental Pediatrics
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• v.49 no.11
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• pp.1186-1193
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• 2006

Purpose : Enterovirus infection is a type of viral infection that occurs relatively frequently in children during summer. It has clinical symptoms of non-specific fever, aseptic encephalomeningitis, gastrointestinal diseases, skin rash and, hand-foot-mouth disease. However, it can also occcaisionally, result in fatal symptoms like myocarditis, epicardial inflammation, transverse myelitis, quadriplegia and etc. There have been epidemic enterovirus studies, but not in the Chungnam area. Therefore, we undertook this study in order to comprehend the cause viruses in this area. Methods: We enlisted 157 children hospitalized with enteroviral infections at Soonchunhyang University hospital in Cheonan between May and August 2005. Cerebrospinal fluids or feces were collected during the acute phase after hospitalization, and observed the cytopathic effects caused by enterovirus and using reverse transcription polymerase chain reaction (RT-PCR). Results : The number of children hospitalized due to possible enteroviral infection during the period of study was 157. The number of children who tested positive with the reverse transcription polymerase chain reaction totalled 32 cases (20.4 percent). Among the children with entroviral diseases, 20 were male and 12 were female, thus the sex ratio of male to female was 1.67:1. Their clinical symptoms included fever most frequently (93.7 percent), was followed by headaches (90.0 percent), meningeal irritation signs (65.0 percent), and abdominal pain (30.0 percent). As for the type of isolated enterovirus, there were 17 cases of echovirus 18 and 6 cases of coxsackievirus B5. Furthermore, there were 2 cases of echovirus 9, 1 case of coxsackievirus A6 and coxsackievirus B3, respectively. But 5 cases were not determined by genotype. Conclusion : Echovirus 18 is circulating in Korea. We reported on identified enteroviruses, including echovirus 18, using RT-PCR in the Chungnam area during the summer of 2005.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1982.05a
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• pp.13.2-14
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• 1982

Otitis media with effusion, described first by Politzer (1867), is closely related with the function of auditory tube, but its etiology and pathogenesis are not clearly defined yet. There are many theories about its pathogenesis including hydrops ex vacuo theory which was most reliable nowadays. In this paper, using cats in experimental animals, hydrops ex vacuo theory was proved and cytological study of the effusion and light microscopic observation of the middle ear mucosa in otitis media with effusion were done. The results were as follows: 1) The effusion was found in all experimental groups after eighteen hours of the auditory tube obstruction. 2) In the cytological study of effusion by smear technic, Polymorpholeukocytes were dominant in earlier days but monoculear cells were soon increased and no eosinophils were found. 3) In the culture of the effusion, no bacteria was cultured. 4) By opeating microscope, hypertrophy of the middle ear mucosa observed especially in the fourteen days after auditory tube obstruction and effusion was most remarkable in the fourteen days, also. 5) By light microscopy, there were epithelial hyperplasia, proliferation of goblet cells, capillaries and infiltration of inflammatory cells which showed same distribution as smear technic.

• Pediatric Infection and Vaccine
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• v.8 no.2
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• pp.213-221
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• 2001

Propose : Tsutsugamushi fever is a acute febrile disease, which is caused by O. tsutsugamushi. Recently, this disease is increasingly reported in children. This study was undertaken to investigate clinical features of tsutsugamushi fever in children. Methods : This study involved 17 children with tsutsugamushi fever who were admitted to Masan Samsung hospital between September 1997 and December 2000. We investigated the age, sex ratio, clinical manifestations, laboratory findings, response of therapy and prognosis. Results : The age of patients was $6.9{\pm}3.6$ years, ranging from 6 months to 12 years and male predilection(58.8%) was noted and all cases of patients occured in October or November. The most common symptoms were fever in all cases and headache in 8(47.1%). The most common signs were skin rash in all cases, eschar in 14(82.4%) and lymphadenopathy 8(47.1%). Locations of the eschars were back and inguinal area in each 3 cases, neck and chest in each 2, popliteal area in 2, scalp and thigh in each 1. Laboratory findings included anemia in 1 case, leukopenia and thrombocytopenia in each 5, hematuria and proteinuria in each 1, ESR elevation in 2 and positive CRP in 12, AST elevation in 9 and ALT elevation in 7. Serologic diagnosis was made by passive hemagglutination assay(PHA) in 8 cases(47%) on admission, 4 cases in initial negative group were performed follow-up test at 2nd or 3rd weeks of illness and then all cases of 4 were converted to positive reaction. Clinical improvement was noticed in all cases after treatment to chloramhenicol or doxycycline. Mean duration for defervescence after treatment was $1.4{\pm}0.8$ days. Complications were interstitial pneumonia in 1 case and aseptic meningitis in 3, but all cases of patients were recovered without sequelae or recurrence. Conclusions : Tsutsugamushi fever in children was similiar to adult in the clinical features except male predilection. Early diagnosis and empirical treatment based on clinical manifestations such as fever, skin rash, eschar, lymphadenopathy is important and serologic diagnosis need to perform follow-up test at 2nd or 3rd weeks of illness.