• Journal of Environmental Health Sciences
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• v.49 no.5
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• pp.251-261
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• 2023

Background: This paper deals with the study of natural radioactivity in rocks from Ogun State in Southwestern Nigeria. The aim is to determine radiation emissions from rocks in order to estimate radiation hazard indices. Objectives: The following objectives were targeted: 1. To determine radiation emissions from each type of rocks; 2. To estimate radiation hazard indices based on the rocks; 3. To correlate the activity concentrations of radionuclides with major oxides. Methods: The samples were analyzed using a NaI (Tl) gamma ray spectrometric detector and PerkinElmer AAnalyst 400 AAS spectrometer. Results: The activity of ⁴⁰K, ²²⁶Ra, and ²³²Th were found in order of decreasing magnitude from pegmatite>granite>migmatite. In contrast, lower concentrations were found in shale, phosphate, clay stone, sandstone and limestone. The mean absorbed doses were 125±23 nGyh^-1 (migmatite), 74±13 nGy/h (granite), 72±13 nGyh^-1 (pegmatite), 64±09 nGyh^-1 (quartzite), 45±16 nGyh^-1 (shale), 41±09 nGyh^-1 (limestone), 41±11 nGyh^-1 (clay stone), 24±03 nGyh^-1 (phosphate), and 21±10 nGyh^-1 (sandstone). The outdoor effective dose rates in all rock samples were slightly higher than the world average dose value of 0.34 mSvy^-1. The percentage composition of SiO₂ in the rock samples was above 50 wt% except for in the limestone, shale and phosphate. Al₂O₃ ranged from 4.10~21.24 wt%, Fe₂O₃ from 0.39~7.5 wt%, and CaO from 0.09-46.6 wt%. In addition, Na₂O and K₂O were present in at least 5 wt%. Other major oxides, including TiO₂, P₂O₅, K₂O, MnO, MgO and Na₂O were depleted. Conclusions: The findings suggest that Ogun State may be described as a region with elevated background radiation. It is recommended that houses should be constructed with good cross ventilation and residences should use home radiation monitoring instruments to monitor radon emanating from walls.

• Annals of Occupational and Environmental Medicine
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• v.34
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• pp.7.1-7.10
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• 2022

Background: Occupational skin diseases are skin conditions that occur or worsen in relation to work and known to be the second most common type of occupational disease affecting individuals in the United States. In Korea, epidemiological reports related to occupational skin diseases are rare. But, no cases of occupational contact dermatitis caused by welding and grinding work have been reported previously. Case presentation: Nine male workers working in the production department for liquefied natural gas (LNG) ships in Ulsan complained of erythematous papules/patches and itching in various areas of the body after welding and grinding work. The work environment monitoring report revealed that the amount of nickel dust exceeded the time weighted average (TWA) and poor local ventilation status. Based on the symptoms and the overall results of surveys, several tests, and work environment monitoring report, the 2 workers who had positive patch-test reactions to nickel were diagnosed with nickel dust-induced allergic contact dermatitis. The other 7 workers were diagnosed that there was a high probability that they had nickel dust-induced irritant contact dermatitis. The 2 workers who had nickel dust-induced allergic contact dermatitis were recommended to switch their jobs. Conclusions: Nickel is one of the most common cause of allergic contact dermatitis. In this case, the dust was assumed to be created by welding work with a high nickel content new welding rod and subsequent grinding work, and the concentration of this dust exceeded the time weighted average. Thus, it is thought that the nickel dust may have caused contact dermatitis through continuous contact with the workers' exposed skin in a poorly ventilated space. Currently, several domestic shipbuilding companies are manufacturing LNG tankers using a new construction method. Consequently, it is highly likely that similar cases will occur in the future, which makes this case report meaningful.

• The Journal of Korean Society for School & Community Health Education
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• v.1 no.1
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• pp.11-43
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• 2000

The purpose of this study was, through analyzing the previous researches, to grasp the present status of environment of school building(ESB), research the sundry records of each element and, through comparative analysis of the standard of ESB in Korea, the United States, and Japan, select the normative standard of ESB, to clarify the point at issue presented in Regulation of Construction & facility Management for Elementary and and Secondary School in Korea, and to suggest an alternative preliminary standard of ESB. To carry out a research for this purpose, these were required: 1. to investigate the existing present status of ESB, 2. to make a comparative analysis of the standard of ESB in each country, 3. to suggest the normative standard of preliminary standard of ESB, 4. to analyze the controversial points of the standard of ESB in Korea, 5. to suggest an alternative preliminary standard of ESB. The conclusions were as follows: 1. Putting, through analyzing the previous researches, the existing present status of ESB together, it seemed that lighting environment, indoor air environment and noise environment were all in poor conditions. 2. In the result of a comparative analysis of the standard of ESB in Korea, Japan and the United States, in Korea the factors of each lighting and indoor air environment were not presented properly, in Japan, in lighting environment aspect, the standard on natural lighting and the factors on brightness were not presented., and in the USA the essential factors of each environment were throughly presented. In the comparison of the standards on each factor, Korea showed that the standard level presented was less properly prescribed than those of the USA and Japan but it also showed that the standard levels prescribed in the USA and in Japan were mostly similar to the standard levels in records investigated. 3. With the result of the normative standard selection on School Builiding environment factor of prescribed in this study, the controversial points of the standard of ESB in Korea were analyzed and the result was utilized to suggest new preliminary standard of ESB. 4. As the result of the analysis of the controversial points of the standard of ESB in Korea, it was found that the standard of ESB in Korea should be established on a basis of School Health Act and be concretely presented in School Health Regulation and School Health Rule. The factors of each environment was improperly presented in the existing standard of ESB in Korea. Moreover the standard of them was inferior to that of the records investigated and those of in the USA and in Japan and it also showed that the standard of it in Korea was improper to maintain Comfortable Learning Environment. 5. A suggested preliminary standard of ESB acquired through above study as follows: 1) In this study a new kind of preliminary standard of ESB is divided into lighting environment, indoor air environment, noise environment, odor environment and for above classification, reasonable factor and standard should be established and the controling way on each standard and countermeasures against it should be considered. 2) In lighting environment, the factors of natural lighting are divided into daylight rate, brightness, glare. In the standard on each factor, daylight rate should secure 5% of a mean daylight rate and 2% of a minimum daylight rate, brightness ratio of maximum illumination to minimum illumination should be under 10:1, and in glare there should not be an occurrence factor from a reflector outside of the classroom. And the factors of unnatural lighting are illumination, brightness, and glare. In the standard on each factor, illumination should be 750 lux or more, brightness ratio should be under 3 to 1, and glare should not occur. And Optimal reflection rate(%) of Colors and Facilities of Classroom which influences lighting environment should be considered. 3) In indoor air environment factors, thermal factors are divided into (1) room temperature, (2) relative humidity, (3) room air movement, (4) radiation heat, and harmful gases (5) CO, (6) $CO_2$ that are proceeded from using the heating fuel such as oval briquettes, firewood, charcoal being used in most of the classroom, and finally (7) dust. In the standard on each factor, the next are necessary; room temperature: $16^{\circ}C{\sim}26^{\circ}C$(summer : $E.T18.9{\sim}23.8^{\circ}C$, winter: $E.T16.7{\sim}21.7^{\circ}C$), relative humidity: $30{\sim}80%$, room air movement: under 0.5m/sec, radiation heat: under $5^{\circ}C$ gap between dry-bulb temperature and wet-bulb temperature, below 1000 ppm of ca and below 10ppm of $CO_2$, dust: below 0.10 $mg/m^3$ of Volume of dust in indoor air, and ventilation standard($CO_2$) for purification of indoor air : once/6 min.(about 7 times/40 min.) in an airtight classroom. 4) In the standard on noise environment, noise level should be under 40 dB(A) and the noise measuring way and the countermeasures against it should be considered. 5) In the standard on odor environment, odor level under Physical Method should be under 2 degrees, and the inspecting way and the countermeasures against it should be considered.

• Journal of Animal Environmental Science
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• v.15 no.3
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• pp.231-240
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• 2009

In this research pig house facilities what are 3,029 houses hold over 1000 heads were surveyed by scale and province. Full-time farms hold over 1000 heads breed total 7,229,892 heads. And farms breed 2,386.9 heads averagely. Pig houses were constructed august 1995 averagely. Each of houses have $3,017.2\;m^2$ scale. The construction type of pig house was winch-curtain type 77.2% which was most popular, confined type 51.3%, litter type 7.4% and loft type 4.6%. The winch-curtain type was popular than windowless type in pig farms which have 1,000-1,999 heads. But pig house construction type which have more than over 10,000 heads was windowless type more than winch-curtain type. Manure removing type was slurry 72.3% and scraper 38.5% in farms which have 1,000-1,999 heads. Manure removing type was slurry 83.3% in farms which have over 10,000 heads. Proportion of roof type of pig house was slate 51.2%, panel 46.1%. But in middle or small farms, slate type was only 25.0%. Proportion of wall type of pig house was 41.9%, block 21.9%, concrete 7.6%, winch-curtain 6.3%, and bnck 5.9%. Ventilation type of pig house was natural winch 46.1%, mechanical windowless 69.8% and mixed type 53.1%. So, mechanical windowless type was popular than natural winch type. Especially the farm scale is bigger the mechanical widowless type was more. Utilization period of pig house was 8.1 years about automatic feeder, 8.3 years about waterer, 8.2 years about electric facilities and 9.0 years about floor material. Thus, almost of facilities were used at least 8 years.

• Journal of Animal Environmental Science
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• v.15 no.1
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• pp.37-50
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• 2009

The purpose of this study was to investigate the effects of on-farm management systems(including the farm size, stocking density of growing-finishing phase, proportion of finisher diet and type of growing-finishing building) and pre-slaughter handling(including the transportation time and loading time) on carcass grade, the incidence of PSE pork, the meat quality score for intra-muscle fat, inter-muscle fat, subcutaneous fat and score for elasticity of market pigs. For this study, 248,787 pigs of 53 different farms were used to establish the pork quality assurance program and to meet the comsumer's need. The results are summarized as follows. 1. The farm size had significant influence on carcass grade, in which showing the higher grade by increasing the farm size. However, the incidence of PSE pork were not significantly differences among the farm size. The meat quality score for intra-muscle fat, inter-muscle fat, subcutaneous fat and score for elasticity of market pigs were not significant influenced by farm size. 2. The stocking density of growing-finishing phase was statistically significant for carcass grade, in which showing the higher grade in mid density group. However, the incidence of PSE pork was higher in high density group. The meat quality score for intra-muscle fat, inter-muscle fat and elasticity of market pigs were greater in mid density groups, but not influenced by stocking density for subcutaneous fat score. 3. The carcass grade and the incidence of PSE pork were not significantly influenced by transportation time. However, transportation time significantly affected the meat quality score, the meat quality score for intra-muscle fat, inter-muscle fat, subcutaneous fat and elasticity of the carcasses were superior in more than 1 hour transportation groups. 4. At any time loading, the carcass grade and PSE incidence were not significantly differences. However, the meat quality score for intra-muscle fat, inter-muscle fat and elasticity of market pigs were superior in before 10 AM groups, but not influenced by loading time for subcutaneous fat score. 5. The proportion of finisher diet had not significant influence on carcass grade, but PSE incidence affected by proportion of finisher diet, 21 percent or more group was higher PSE incidence. The meat quality score for intra-muscle fat and inter-muscle fat of the carcasses were superior in 21 percent or more fed finisher diet groups, but elasticity score of carcass had not influenced by the proportion of finisher diet. 6. The type of growing-finishing building was affected the carcass grade and PSE incidence of the market pigs, carcass grade and PSE incidence were superior in enclosed mechanical ventilation building groups. The meat quality score for intra-muscle fat and inter-muscle fat of the carcasses were not significantly differences by the type of finishing building, but the score of subcutaneous fat and elasticity of carcass were superior in opened natural ventilation building groups. In conclusion, the results of this study suggest that we have more precise on-farm management practice and the knowledge related to pre-slaughter handling skills to reduce the stress and improve the status of welfare of market pigs.

• Korean Security Journal
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• no.13
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• pp.423-449
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• 2007

This research is to investigate the detention facilities of police stations and their real operations through the perceptions of detainees at police station cells and to present the policy suggestions for them. To fulfill the research, a questionnaire was made out on the basis of 'the Regulation on Detention and Escort for Suspects'. 'the Regulation on a Standard Plan for Detention Facilities' and 'the Regulation on the Lowest Standard to Treat Detainees' ; and detainees at 23 police station cells under the jurisdiction of Kyungbuk Local Police Agency were asked to answer it. Policy suggestions following from the result of the investigation of detainees' perceptions of the detention facilities of the police stations are as follows; Firstly, the structure of police station cells should be arranged in straight lines in order to take their human rights into consideration and more detention facilities are needed to be built in order to separate male, female, handicapped and juvenile inmates. Secondly, shower rooms and washrooms outside the cells should always be open to detainees whenever they need to be used. Thirdly, any detention facilities deficient in fire fighting equipment should have exit doors installed as soon as possible in case of an emergency and provide sufficient fire extinguishers considering the number of detainees and the size of the facilities. Fourthly, the detention facilities should have sufficient windows for ventilation and take necessary measures to obtain natural lighting instead of electric lighting. Fifthly, air conditioners should be equipped properly taking account of the number of detainees and the dimensions of the facilities. Policy suggestions according to the result of the investigation of detainees' perceptions of the operation of detention facilities of police stations are as follows; Firstly, the problem of operating the detention facilities must deal with worn-out facilities and measures to secure the budget should be taken as soon as possible. Secondly, considering that most detained suspects have difficulties in livelihood, daily necessaries must be issued to them. Thirdly, personal belongings deposited by inmates must be properly managed with the same documentation throughout the police station detention facilities. The number of female guards to take exclusive charge of the physical checkups and processing of female detainees should be increased. Also the facilities for handicapped detainees must be expanded, improved and managed properly. Fourthly, except for handcuffs and ropes to bind detainees in the detention facilities, helmets to prevent self-harm must be withdrawn. The budget to improve the quality of meal issued by the government must be urgently secured and the price of private food sent to detainees must be readjusted to be in line with the consumer price. Health and medical care and sanitation for detainees must be substantial, and also sunbathing and outdoor exercises should be allowed to detainees.

• Journal of Bio-Environment Control
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• v.29 no.1
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• pp.52-61
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• 2020

The natural change of winter night temperature from 00:00 to 04:30 O'clock with the different height of thermal screen in a venlo type glasshouse (W59×L68×H5.9 m) was studied using computational fluid dynamics (CFD). At the early stage of CFD analysis, the room temperature decrease of glasshouse with the 5.9 m height of thermal screen were faster than it with the 4.1m height of thermal screen, but at 2 hr after analysis it was slower than in it with the 4,1m, the temperature difference was 0.6℃ after 4 hr. If we consider that turn on the heater when the temperature were decrease below 13℃ at 1hr after CFD analysis, it is good for energy saving in the glasshouse with the 4.1 m height of thermal screen rather than in it with the 5.9 m height, because of the temperature decrease were slow during 2 hrs after analysis. The airflow at the height of 2 m which were grown tomato were fast and wide in the glasshouse with the 5.9 m height thermal screen rather than in it with the 4.1 m, the speed difference was 0.034m·s^-1 at 1hr after CFD analysis. The effect of temperature decrease in summer season were compared with the different height of shading screen from 12:00 to 14:30 O'clock. The height of shading screen were 5.7, 3.9 m, the gap of it were 30%. The air-inflow quantity by the fan with duct at lower part of venlo glasshouse was 0.67 ㎥·s^-1 until 1hr and to increase 3 times of it from 1hr after analysis. The roof window were open 100%. Until 1hr of CFD analysis, the temperature in the 30% open of shading screen was 0.9℃ higher than in the none shading screen. From 13:00 O'clock when the air-inlet quantity to increase 3 times, the temperature in case 30% gap of shading screen were decreased compare with the none shading screen, the temperature difference was 0.5℃ at 14:30 O'clock. The temperature on the floor surface in case 30% gap of shading screen were lower with it's height increase, the temperature difference was 8℃ compare with none shading screen. The relative humidity difference were insignificant by the height and gap of shading screen.

• Neonatal Medicine
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• v.15 no.2
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• pp.142-151
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• 2008

Purpose : The aim of this study was to compare the clinical effects of modified porcine (Curosurf$^{(R)}$) and bovine (Newfactan$^{(R)}$) surfactants in the treatment of neonatal respiratory distress syndrome. Methods : Between April 2004 and December 2006, 65 neonates (birth weight ${\leq}$2,500 g and gestational age ${\leq}$35 weeks) with neonatal respiratory distress syndrome were treated in our neonatal intensive care unit with surfactant. Thirty-one neonates received Curosurf$^{(R)}$ and 34 neonates received Newfactan$^{(R)}$. The neonates were not enrolled if they had major congenital anomalies or meconium aspiration syndrome. We compared the changes in respiratory parameters after surfactant instillation, the incidences of acute and chronic complications, and the mortality between the two treatment groups. Results : Neonatal and maternal demographic characteristics were not different between the groups. The patterns of change in the respiratory parameters after surfactant instillation were not statistically different between the groups. The incidences of surfactant reinstillation and acute complications, such as pneumothorax, patent ductus arteriosus, pulmonary hemorrhage, and grade 3-4 intraventricular hemorrhage, were not different between the neonates who received Curosurf$^{(R)}$ and the neonates who received Newfactan$^{(R)}$. There were no statistically significant differences in the duration of mechanical ventilation, oxygen therapy, hospitalization, prevalence of bronchopulmonary dysplasia, periventricular leukomalacia, retinopathy of prematurity, necrotizing enterocolitis, and mortality between the groups. Conclusion : In the present comparative study, no significant differences in the clinical effects of Curosurf$^{(R)}$ and Newfactan$^{(R)}$ were observed.

• Journal of Bio-Environment Control
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• v.30 no.4
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• pp.328-334
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• 2021

This study was conducted to analyze the effect of fog cooling during daytime and heatpump cooling at night in greenhouses in summer. During daytime, the average temp. and RH of the control greenhouse which had shading screen were 32.1℃ and 59.4%. and the average temp. and RH of the test greenhouse which had fog cooling were 30.0℃ and 74.3%. At this time, the average outside temp. and RH were 31.4℃ and 57.7%. So, the temp. of the control was 0.7℃ higher than outside temp., but the temp. of the test was 1.4℃ lower than outside and 2.1℃ lower than control. The average RH was 74.3% in the test and 59.4% in control. The average temp. and RH of the control greenhouse which had natural ventilation at night were 25.2℃ and 85.1%, and the average temp. and RH of the test greenhouse which had heat pump cooling were 23.4℃, 82.4%. The average outside temp. and RH at night were 24.4℃ and 88.2%. The temp. of the control was 0.8℃ higher than outside temp., but the temp. of the test was 1.0℃ lower than outside and 1.8℃ lower than control. The average RH was 82.4% in test and 85.1% in control greenhouse. There was no significant difference between the plants growth eight weeks after planting. But after the cooling treatment, the values of stem diameter, plant height, chlorophyll in test were higher than control. The total yield was 81.3kg in test, 73.8kg in control, so yield of test was 10.2% higher than control. As a result of economic analysis, 142,166 won in profits occurred in control greenhouse, but 28,727 won in losses occurred in test greenhouse, indicating that cooling treatment was less economical.

• Clinical and Experimental Pediatrics
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• v.48 no.7
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• pp.737-744
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• 2005

Purpose : Infants and children with cardiovascular diseases often present with respiratory symptoms. However, missed or delayed evaluation for potential airway problem may complicate overall prognosis. The aim of this study is to determine the clinical characteristics of these patients and explore the cause of airway problem. Methods : We reviewed the medical records of 64 patients(M : F=33:31, mean age : $6.3{\pm}7.5$ months) whose airway problems were proven by computed tomography or bronchoscopy in perioperative periods at the Asan Medical Center from January 1997 to June 2004. Patients were divided into two groups based on the duration of ventilator care : ${\leq}7$ days(group 1 : 23 cases, M : F=10 : 13) and >7 days(group 2 : 41 cases, M : F=23 : 18). Results : The patients in group 2 significantly developed more post-operative respiratory symptoms than group 1(P<0.001) and had more airway problems including extrinsic obstruction, intrinsic anomaly, and combined problem than group 1 although not significantly different(P=0.082). Among underlying diseases, the most common diseases were vascular anomaly(26.2 percent) and aortic arch anomaly(26.2 percent) in group 1 and pulmonary atresia with ventricular septal defect(22.4 percent) in group 2. The most frequent respiratory symptoms were recurrent wheezing pre-operatively and failure of ventilator weaning post-operatively. The major types of airway anomaly were tracheomalacia and tracheal stenosis(in each case 18.2 percent). Nineteen patients with persistent airway problems underwent aortopexy or other vascular correction. Of the 19 patients, 13(68.4 percent) were improved, but 2 failed in weaning ventilator and 4 died of non-airway problems. Conclusion : Early evaluation and treatment for potential airway problems may affect natural or surgical prognosis in patients with cardiovascular diseases presenting with respiratory symptoms.