• Journal of the Korean Institute of Gas
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• v.12 no.1
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• pp.42-47
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• 2008

The demand of gas as an eco-friendly energy source has being increased. With the demand of gas, the use of gas is also increased, so injury and loss of life by the explosion and fire have been increasing every year. Hence the influence on over-pressure caused by Vapor Cloud Explosion in enclosure of experimental booth was calculated by using the Hopkinson's scaling law and damage effect by the accident to a human body was estimated by applying the probit model. As a result of the damage estimation conducted by using the probit model, both the damage possibility of explosion overpressure to human over 3 meters away and that of overpressure to tympanum rupture over 25 meters away from the explosion shows nothing.

• Fire Science and Engineering
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• v.32 no.4
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• pp.35-41
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• 2018

The purpose of study intends to investigate effects of repetitive work and workload for body while wearing firefighting protective clothing in hot conditions and to provide the basic data for the safety of firefighter. The experimental temperature is WBGT $30^{\circ}C$ and the work intensity is 3, 9 METs. The experiment is processed 15 minutes (Ex1), 15 minutes rest (Rest), 15 minutes (Ex2) in order of time. A comparative experiment was carried out for firefighting school students(9 persons; $24.3{\pm}0.71$ years old) wearing firefighting protective clothing. When workload is increased from 3 METs to 9 METs, mean skin temperature change (33.3%), tympanic temperature change (242.9%), heart rate (36.2%), respiration rate (53.9%), RPE (81.6%), thermal Sensation (20.8%), weight loss (60.0%), glucose (-4.4%), lactate (41.7%) are statistically significantly higher. As a result, it is considered that repetitive work and workload have a strong effect on the body when wearing firefighting protective clothing in hot conditions.

• Journal of Wetlands Research
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• v.12 no.3
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• pp.107-127
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• 2010

This research is about the monitoring of people's consciousness on ecosystem change after coastal restoration project in Gangjin Bay. Tidal flat ecosystem of Ganjin Bay was major producing district of short-necked clam in Jeonnam Province. Owing to coastal restoration project (sand gathering and dredging) during 5 years, however, ecosystem was disturbed and harvesting of fish was decreased. Although a few of ark shell and oyster are harvested but drastically decreased. Even aging and depopulation is general situation like other rural regions, life pattern of villages and depopulation in Gangjin Bay was influenced by drastic decreasing of income. As the results of social monitoring, drastic decreasing of fish and shell in Gangjin Bay is significantly concerned with coastal restoration project (sand gathering and dredging) and also with difficulty of fresh-water inflow to coastal bay because of Jangheung Dam. In order to get the detail information on the cause and consequence of ecosystem change in tidal flat, it is necessary to apply the long-term socio-economic monitoring as well as biological and ecosystem monitoring.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.3
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• pp.223-230
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• 2010

To compare seed collection and the growth of Anadara subcrenata in Suncheon and Boseong Bays, environmental factors and the growth of larvae and spats were investigated from August 2008 to July 2009 in commercial farming sites in both bays. The variation in water temperature in both bays was similar, but the salinity was lower in Suncheon Bay than in Boseong Bay. The chlorophyll-a content was higher in Suncheon Bay due to the large inflow of freshwater. The density and shell length of A. subcrenata larvae did not differ significantly between the two bays. However, the relative growth of shell height to shell length was significantly higher in Suncheon Bay (P<0.05). The growth of A. subcrenata spats attached to a collector was significantly faster in Suncheon Bay (P<0.05). The spats in Suncheon and Boseong Bays grew to 24.3 and 21.0 mm in shell length, respectively, within 1 year after spawning, and the shell length reached 35.6 and 34.8 mm, respectively, within 2 years of spawning. The initial spats density was higher in Boseong Bay, but the growth of spats was better in Suncheon Bay. The faster growth of A. subcrenata in Suncheon Bay can be explained by the high chlorophyll-a content in this bay. Based on the low survival (%) and slower growth rate of spats in Boseong Bay, the commercial culture density of A. subcrenata in Boseong Bay should be reduced to the optimum level of the carrying capacity.

• Pediatric Infection and Vaccine
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• v.9 no.1
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• pp.110-116
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• 2002

Tuberculous otitis media is a very rare disease in extrapulmonary tuberculosis and in chronic otitis media nowadays. The characteristic signs seem to have altered from the past ones. And the suspicion index is very low that there is often a considerable delay prior to diagnosis. This might result in irreversible complications such as hearing loss, facial nerve paralysis and labyrinthitis. It is difficult to be defined by culture, so many patients with tuberculous otitis media are subjected to have surgery without a correct etiologic diagnosis. Therefore bacteriologic study of secretion and pathologic examinations of biopsied tissue are mandatory. We report one year and 11 months old boy with tuberculous otitis media having painful otorrhea and perforated tympanic membrane diagnosed by histologic finding and polymerase chain reaction(PCR). And we would like to emphasize the fact that tuberculous otitis media must be considered in the differential diagnosis of persistent suppurative otitis media despite appropriate antibiotic therapy considering the increasing tendency in incidence of Tuberculosis in Korea these days.

• Journal of the Korea Convergence Society
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• v.10 no.3
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• pp.73-79
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• 2019

This study simulated external ear canal modeling with different external ear canal lengths, vertical flexion angles, and inner/outer diameter ratios using digital imaging and communications in medicine(DICOM) of the head temporal region and measured the acoustic sensitivity. The experiment was performed by increasing the audible frequency for humans by 200 Hz and expressing the frequency constantly transmitted at 1 Pa as the eardrum acoustic volume and presented the measurements by linear and quadratic curve regression analysis. The results showed that the longer the external ear canal length and the higher the ratio of the outer/inner diameter, the faster the acoustic response at lower frequencies. The acoustic sensitivity correlation of the meta-model using regression analysis showed a 77% influence by the external ear canal length and 5% by the external/internal diameter ratio, while the vertical flexion angle did not show a significant relationship. This showed that auditory acoustic sensitivity of humans is a factor that reacts faster at a low frequency when the external ear canal length is longer and when the difference between the outer and inner diameter is higher.

• Clinical and Experimental Pediatrics
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• v.46 no.5
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• pp.459-466
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• 2003

Purpose : AOM is the most common bacterial URI in children. The bacteriology and antibiotic Tx of AOM in children has been studied in many countries. But, there is few study of causative pathogens and antibiotic Tx of AOM in our country. In this aspect, we performed prospective clinical study to confirm the causative pathogens and assess the clinical responses of cefprozil in AOM patients. Methods : Thirty three AOM patients enrolled in this study. Tympanocentesis for isolation of causative pathogens were performed before Tx of cefprozil. The study patients received cefprozil with dose of 15 mg/kg/bid.po/day for 10-12 days, and initially assessed the clinical response at 4-5 days after receiving cefprozil and finally at the end visit. In vitro susceptibility tests of cefprozil to isolated pathogens were done by disc diffusion method, and in vitro susceptibility tests of cefaclor and cefixime to isolated pathogens were simultaneously performed. Results : Bacterial pathogens[S. pneumoniae(10), H. influenzae(5), S. aureus(2), M. catarrhalis(1) and Group A stretococcus(1)] were isolated from 19 patients. Clinically, all patients had history of abrupt high fever except one. Tympanic perforation was dominant in pathogens isolated cases, and otalgia was significantly developed in non-pathogens isolated cases. The ages of pathogens isolated cases were usually below 2 years. Eighty four point nine percent of the patients including two cases with isolation of intermediate resistant S. pneumoniae were clinically improved. Antimicrobial in vitro activity to S. pneumoniae of cefprozil were superior than that of cefacor and cefixime. Conclusion : We confirm that bacteria has the causative role in about 60% cases, and S. pneumoniae is the most common pathogen. Clinically, there were some differences in symptoms, signs and ages between pathogens isolated and non-pathogens isolated cases. The clinical responses of cefprozil in our patients revealed similar outcomes to other countries. And we reconfirm that cefprozil may be clinically effective in cases of AOM due to intermediate resistant S. pneumoniae.

• Sleep Medicine and Psychophysiology
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• v.9 no.1
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• pp.41-47
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• 2002

Objectives: In a number of simulated night shift studies, timed exposure to bright light improves sleep quality and work performance. We evaluated the effect of bright light on adaptation to night shift work with a field study. Methods: Five female nurses working shifts at Korea University Hospital were recruited for participation in this study. We investigated two series of six consecutive shift rotations comprising three day and three night shifts, using wrist Actigraphy, the Stanford Sleepiness Scale, Visual-analogue scales, STIM and tympanic membrane temperature for daytime sleep quality, alertness, subjective feeling, attention performance, and temperature rhythm. The subjects were exposed to bright light (2,500 lux) from 24:00 to 04:00 a.m. on three consecutive night shifts during the second series, whereas they worked under normal lightening (650 lux) conditions during the first series. Results: Actigraphic assessment of daytime sleep showed no significant difference between the first and third night shift in both baseline and light exposure phase. The mean lowest temperature shifted earlier during baseline phase but not during the light exposure phase. Also, the score for subjective feelings of depression, anxiety, physical discomfort and sleepiness was significantly higher in the third night shift than the first during baseline phase but not during the light exposure phase. Attention and attention switching ability was significantly improved in the third night shift compared to the first night during the light exposure phase but there were no significant changes during the baseline phase. Conclusion: This result suggests that there were no significant differences between the two phases in measures of quality of daytime sleep, but subjective feelings, attention and alertness were enhanced during light exposure. Although some placebo effects and learning effects might influence this result, bright light exposure between midnight and 4:00 a.m. may improve adaptation to night shift. In future, further controlled studies with a larger sample size, including melatonin measurement, are needed for real shift workers.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1982.05a
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• pp.5.2-5
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• 1982

With the improvement of living standard and socioenvironmental change, esophageal stricture due to acetic acid, Hcl, insecticides and lye has led to decrease remarkably. Esophageal stricture has decreased because of immediate treatment and adequate management. However there are still sporadic incidents of esophageal stricture due to inadequate treatment and uncooperation of patients. The authors recently have experienced seven severe cases of esophageal stricture. All six patients were treated with 18-51 French Sippy esophageal dilating bougie. One patient was transfered to thoracic surgery department due to complete esophageal obstruction. Case 1. A 23 year old housewife who ingested Hcl for suicide. After Witzel's operation, she visited to dilate esophageal first constriction stircture due to swallowing difficulty postoperation 2 months later. We were treated successfully. Case 2. A case of esophageal stricuture in the second and third physiologic constriction part. The patient was 51 years old man who ingested lye accidently, and was dilated by bougination. Case 3. The patient was 43 year-old man who ingested acetic acid as a mistake and was treated inadequately at hopsital. Inspite of treatment, esophageal stricture developed at the third physiologic part. We are trying to dilate the esophagues now. Case 4. The patient was 55 year-old woman who had ingested Hcl for the purpose of suicidal attempt. 2 months later gastroduodenal anastomoisis due to pyloric region stenosis, the first physiologic constriction stricture was dilated successfully. Case 5. The patient was 41 year-old woman who ingested Hcl for suicide 4 months ago. There was indwelled orogastric tube for 1 month but esophageal stricture developed at the first and 3rd constriction part. She was treated by using a bougination. Case 6. An athlete 21 year old man, ingested acetic acid 2 spoonful per 3 days by purpose in order to soften the bone for last 14 months. There was complete esophageal obsturction in esophagogram and transferred to the thoracic surgery department. Case 7. A 3 year-old girl was ingested lye at a accident. She had a bougination for 16 months under the general anesthesia for dilation due to whole irregular esophageal stricture. She developed lower esophageal perforation, but healed eventually.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1982.05a
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• pp.14.2-15
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• 1982

Serous otitis media (SOM) is one of the most common otologic diseases which was first discribed by Politzer in 1869. Currentely, among many methods introduced to treat SOM, ventilation tube insertion is considered to be the most popular and standard method being used. However due to complication of it, there remains many disputable various problems. In order to review the clinical aspect of SOM and search for the effects and safety of ventilation tube, we studied 97 SOM patients, who had performed V-tube from Jan. 1981 to Feb. 1982 at ENT dept. of Severance Hospital. Analizing the clinical symptoms, age distribution, associated disease, otoscopic findings of ear drum, degree of hearing loss, hearing gain after insertion of V-tube and complications, following results were obtained. 1) As a subjective symptom, among 29 cases all patients had hearing loss, 19 cases (65.6%) had tinnitus, 12 cases (44.4%) had autophony and 10 cases (34.5%) of the patients had sensation of ear fullness. 2) In age distribution, 6 to 10 year old group was most numerous up to 42 cases (43.3%) and 20 years and over was 23 cases (23.5%) 3) In adult group SOM tend to be involved unilaterally whereas young child group had tendency involving bilaterally. 4) 49 cases (50.05%) were associated with tonsillitis and adenoid vegetation, 15 cases (15.5%) were associated with sinusitis, 4 cases (4.1%) had nasal allergy. 5) In preoperative otoscopic findings, 62 ears (47.7%) had retraction, 37 ears (23.6%) had bulging, 34 ears (21.7%) had color change, and 29 ears (19.7%) had no significant findings. 6) In characteristics of middle ear fluid, child group was tend to have mucinous content (84.2%) while adult group had serous content (62.5%). 7) Average preoperative air-bone gap of pure tone was 25.3 dB. 8) 24 ears (72.7%) had over 10 dB of postoperative hearing gain and average hearing gain was 17.2 dB. 9) There were 44 ears (28.1%) of complications. Among them 37 ears (23.6%) had infection, 3 ears had atelectasis, 2 ears had granulation tissue, 2 ears had permanent perforations. 10) Among 37 ears suffered from post-op. infection, 19 ears (51.4%) had initial infection just after insertion of ventilation tube, 18 ears (48.6%) were infected during the course of post-ventilation tube. Of 37 infected ears, 26 ears (70.3%) responded to conservative care, while 11 ears (29.7%) was cured after removal of ventilation tube.