• Journal of Preventive Medicine and Public Health
• /
• v.29 no.2 s.53
• /
• pp.239-254
• /
• 1996

Health services on industrial noisy environment have been provided only for noise-induced hearing loss management until now. But gradually, modem diseases and death have come to be related to stress and mental health deeply, therefore noise-induced mental disorder, like a stress became very important. In this point, the purpose of this study was to analyze the relationship between noise exposure level in worksite and workers' stress symptoms. This study included a survey of 786 manual workers selected from 89 worksites in 21 factories in Puchon. The results were as follows: 1. For demographic characteristics, most of the workers were males(80.8%), the $20\sim29years$ old were 34.5% and those who graduated from high school were 65.3%. The workers whose monthly income ranged from 100,000 to 800,000 won were 37.5% and who have a religion were 47.9%. 2. For occupational characteristics, workers who had worked $1\sim5$ years in the factories were 33.0%. Those who were much for them workload were 43.9% and who worked more than 8 hours a day were 73.9%. Those who were disatisfied with their job and pay were 31.9% and 50.6%. The workers who responsed ventilation condition of their worksites were bad were 51.9% and the dissatisfed with working environment of their worksites were 45.9%. 3. Workers who were suffering from tinnitus were 53.3% and those who perceived hearing loss were 50.1%. Persons who reported they always wore earplugs at work were 35.4%. Those who felt earplugs bigger than their ears were 30.6% and those who experienced eardiseases caused by earplugs were 25.6%. 4. For the noise exposure level in worksite, workers who were exposed to $80\sim90dB$ were 30.3%, $90\sim100dB$ were 26.4% and $50\sim70dB$ were 19.2%. 5. Workers' stress symptoms were significantly related to marital status and their monthly income(p<0.05). Workers who were single and had lower monthly income showed higher PSI (Psychiatric Symptom Index) scores than those who were married and had higher monthly income. Higher PSI scores were also significantly related to $1\sim2$ days hight-work per week, much for them workload, dissatisfaction with their job, and bad relationship with their bosses and coworkers. 6. Higher PSI scores were significantly related to severe tinnitus and perceived hearing losso(p<0.001). Workers who felt the earplugs they use did not fit their ears showed significantly higher PSI scores(p<0.01). Workers who reported that they did not feel they need earplugs showed. significantly higher PSI scores (p<0.05). Increased experience of eardisease caused by earplugs that did not fit were also significantly related to higher PSI scores(p<0.01). 7. The higher noise exposure level in worksite from 80dB was, the more severe stress symptoms including PSI subparts were reported; Anxiety, Anger, Depression, and Cognitive disorder(p<0.001). 5. According to the results of stepwise multiple regression analysis, factors affecting workers' PSI scores were perceived hearing loss$(R^2=0.160)$, noise exposure level in worksite$(R^2=0.110)$, realtionship with coworkers, amount of workload, monthly income and relationship with bosses orderly and the total $R^2$ of this 6 factors was 0.371. 9. The most significant factors that have impact on manual workers' stress symptoms were perceived hearing loss and noise exposure level in worksite, especially noise exposure level in the worksite was the most affective factor on the depression symptom.

• Journal of Internet Computing and Services
• /
• v.21 no.2
• /
• pp.139-148
• /
• 2020

Due to change in circumstances in the 2000s such as severe birthrate decline and shortened military service period, the armed forces of the Republic of Korea is currently turning to technologies and equipments from manpower, developing it to become high-tech, high-speed, and complex, resulting in an environment in which a single mistake could cause a mass mortality crisis.It is also evident that, considering aspects such as safety training curriculums and achievements of advanced countries and private education, hands-on training is a must in preventing suicides and accidents in the military, and establishing safety training centers is crucial for systematic and effective hands-on training.Soldiers who are joining the army as of now have experienced the Internet ever since they were born and easily use both virtual and augmented reality, and the current level of science and technology has developed to the point where most of the public safety experience centers are able to be replaced by virtual and augmented reality (VR/AR). Therefore, considering the aspects such as installation space, construction costs, maintenance costs, user characteristics, and education effects, other than for those trainings where real models and objects are more effective such as first aid training, it is with a strong recommendation that establishing military safety training facilities with VR/AR (Virtual and augmented reality) is a must in the coming future. We have derived the need for hands-on training by considering the development of virtual and augmented reality (VR/AR), analysis of operation status of the public safety experience centers, characteristics of military units, installation and maintenance costs, and proposed plan to establish safety training centers where effective training performance can be achieved at a lower cost than the public safety experience center. In addition, we suggested the scale of the required safety training center and the composition of the experience rooms considering the number of trainees and the environment of each military units. Given this analysis it will contribute to the prevention of military safety and suicide by building a safety training center in the future.

• Korean journal of applied entomology
• /
• v.29 no.3
• /
• pp.209-215
• /
• 1990

Some preliminary studies were conducted to find out whether the levee-burning could justifiable for the suppression of insect pests, particularly the smaller brown planthopper (Laodelphax striatellus F.). Density surveys on pests and their enemies (mostly spiders) were carried out upto the mid May at an experimental paddy field located in Suwon after of it's levee $(72\times1m)$ was burned on Feb. 20, 1987. Results were discussed in relation to density recovering of both pests and their possible enemies (spiders) and summarized as below. Not a single individual of any pest or enemy was found from the levee upto sometime after the levee-burning. Grasses started to grow more vigorously in burned ares than in unburned upto about 60 days after the burning. And densities of both pest and enemies grew higher in burned areas than in unburned from about 75 days after the burning (in Early may). It is suspected that all individuals of pests and enemies fond from the burned areas could have immigrated from the surrounding areas. If levee-burning was carried out in much wider areas, much longer time would be needed to recover the density of both pests and enemies to the center region of the burning. Wingless spiders would require even longer time than winged pest species to re-establish in the center region of the widely burned field. Pirata subpiraticus, the most abundant spider species in Korean paddy fields, starts to move about and searches for food at above $9^{\circ}C$ which is somewhat lower than the critical temperature for the pest species. Thus P. subpiraticus would require more food than other pest species early in the spring, and therefore, it would have lower probability to survive than pest species particularly in burned areas. Experiments for pest suppression with levee-burning would better be carried on in much wider areas, and its justification seems to be discussed after man other disciplines related to both pests and their natural enemies were throughly studied together with their density surveys. However, according to the present point of vie, the opinion that levee-burning is helpful for controlling pests which over winter on levee areas could not be justifiable.

• Journal of Distribution Research
• /
• v.15 no.5
• /
• pp.103-126
• /
• 2010

The development of an industry including distribution sector is influenced by not only government policy but the related firms' behaviors. Recently the large-scale retailers have had more enormous channel power than any other distributors including monopolistic makers. Now is the time for government to prepare some policies against the unfair transaction behaviors by large-scale retailers. In this paper I tried to inquire into the distribution competition policy from a political correspondent point of view related with the transition of distribution system. For the purpose of this article I compared the case of Korea with Japan. According to the results so far inquired, there are some commons and differences in the cases of the two. Some suggestions are as follows. Considering the predominant position the concept of large-scale retailers is to be extended from a single store to numerous chain stores in the political level. Government needs to examine the standard propriety for large-scale retailer; the size of selling area and amount of sales a year. When a large-scale retailer store is to be established, it need to be taken a permit or a pre-inspection. The Fair Trade Commission have to secure the neutrality from Government's strategies. And government should find out the examples of unfair transaction behavior types and prepare some proper guidelines continually. For the last time statistical data by distributors are to be fitted out and the actual investigations for estimating the effects of government policies need to be enforced.

• Radiation Oncology Journal
• /
• v.17 no.2
• /
• pp.158-165
• /
• 1999

Purpose : To investigate the percentage of colonies wi1h16or more cells distribution of human skin fibroblast according to in vitro aging, and to evaluate the relationship between percentage of colonies with 10 or more cells and in vivo donor age in human skin fibroblast culture. Material and Method : C1, C2, C3a, and C3b human skin fibroblast samples from three breast cancer patients were used as subjects. The C1, C2, and C3a donor were 44, 54, and 55 years old, respectively. C3a and C3b cells were isolated from the same person. Single cell suspension of skin fibroblasts was prepared with primary explant technique. One hundred cells are plated into 100m1 tissue culture flask and cultured for two weeks. The colony size was defined as colonies with 16 or more cells. The cultured cell was stained with crystal violet, and number of cells in each colony was determined with stereo microscope at $\times$10 magnification. Passage number of C1, C2, C3a and C3b skin fibroblast were 12th, 17th, and 14th, respectively. Results : Percentage of colonies with 16 or more cells of skin fibroblast samples decreased with increasing in vitro passage number. In contrast, cumulative population doublings of skin fibroblast sample increased with increasing in vitro passage number. Percentage of colonies with 16 or more cells also decreased with increasing population doublings in human skin fibroblast culture. There was strong correlation with percentage of colonies with 16 or more cells and population doublings En C3a skin fibroblast sampie. At the same point of population doublings, the percentage of colonies with 16 or more cells of the young C1 donor was higher level than the old C3a donor. Conclusion : The population doublings increased with increasing in vitro passage number but percentage of colonies with 16 or more cells decreased. The results of this study imply that percentage of colonies with 16 or more cell is useful as a indicator of in vitro human skin fibroblast aging and may estimate the in vivo donor age.

• Journal of Preventive Medicine and Public Health
• /
• v.1 no.1
• /
• pp.51-66
• /
• 1968

During a period of about one year(November '66 to December '67), the Yonsei University College of Medicine conducted a field trial of the oral contraceptive(Ovulen) in order to study its acceptability and use-effectiveness among IUD drop-outs in Koyang county. We can summarize the outstanding findings from this investigation as follows; 1. 61.4% of the IUD drop-outs interviewed (911 women) wanted to use the pill. Most of the reasons for not wanting to use it(352 women) pertained to either use of other contraceptive methods(98) or subfecundity(150) following IUD terminations. Only 83 out of 911 women gave reasons related to the difficulty of obtaining pills. Therefore, we can state that most IUD drop-outs if still in need of a contraceptive methods are in favor of trying the pill, and especially so if this method is conveniently available. 2. The 467 women or 37% of those who terminated IUD use actually visited the clinic for medical screening, and only 11 of them or 2.4% were rejected because of pregnancy and other medical reasons such as cervical erosion, myoma, breast mass, etc. 5.5% or 25 of the 456 women who received the first cycle did not take a single pill during the study period. 3. When we defined those 431 women who accepted and took one or more tablets we found that women over age 30, with 4 or more children, and/or with a higher educational level were the best prospects for recruitment. 4. In accuracy of use, about two thirds of the users started taking the pill on the 5 th day as directed for the first three cycles, but the percentages rose sharply to about 80% in later cycles. Tardiness in starting pill use in the first cycle may have occurred partly because they had to return to the clinic monthly to get each new cycle. Among acceptors who did not quit between cycles, 80 to 90% were regular users, missing two or less tablets in each cycle. 5) More than 60% of the users felt well and sometimes lost their pre-acceptance symptoms. especially dysmenorrhea. However, 27.4% (58 women) had side effects attributable to the pill compund as nausea, vomiting, indigestion, breast tenderness, decreased lactation or breakthrough bleeding. 25.0% (53 women) also complained of medical diseases or symptoms not related to the pill, especially during the first three cycles. However, as the confidence and experience of the client and the field workers grew, the incidence of unrelated medical complaints quickly fell to a lower level in the later cycles. 6. As of the end of this study, on December 31, 1967, 49.2% (212 women) had discontinued the use of the pill for medical reasons as well as for the non medical reasons. Only one case terminated use due to a pregnancy after taking pills. The cumulative continuation rates (by the life table method), were 58.9%, 51.9%, 41.0% at the end of 3 months, 6 months and one year, respectively. These rates are lower than in the U.S. studies. Even when we add the retaking group to the first segment, the continuation rate goes up only about 5% above the first segment rates mentioned above. Possible explanations are different dosages, the newerness of the method and the use of only one point for pill distribution in the country together with a monthly return for cycle 1, 2, 3, and 4-6.

• Korean Journal of Clinical Laboratory Science
• /
• v.48 no.2
• /
• pp.144-152
• /
• 2016

Carotid-artery stenosis may reduce cerebral perfusion, and affect cerebral neuronal activities. We examined the question of whether the recovery of cerebral-perfusion reserve after carotid-artery stenting (CAS) can affect the EEG power-spectrum. Nineteen candidates for CAS were initially recruited. Subtraction imaging of single photon emissary computerized tomography (SPECT) and an electroencephalogram (EEG) were taken twice, before and 1 month after CAS. At each time point, the EEGs were recorded before and after injection of acetazolamide (pre-ACZ EEG and post-ACZ EEG). Finally, 7 patients were enrolled after exclusion of incomplete studies. We obtained the spectral ratio (SR) of each hemisphere. SR was defined as the divided value of the power-spectrum sum of fast activities by that of slow activities. The power-spectrum values between hemispheres were compared using the inter-hemispheric index of spectral ratio (IHISR), and we examined the correlation between the power-spectrum and the cerebral-perfusion reserve. Cerebral-perfusion reserve improved after CAS on the stent side in 6 of 7 patients. In 3 patients with unilateral carotid-artery stenosis, CAS increased SR on the pre-ACZ EEGs, and IHISR on the post-ACZ EEGs. The increases of SR and IHISR were concordant with the increment of cerebral-perfusion reserve. In contrast, the results in the other patients with bilateral stenosis showed complex patterns. The SR of pre-ACZ EEGs and IHISR of post-ACZ EEGs may be useful electrophysiological markers for the blood-flow reserve after CAS in patients with unilateral carotid-artery stenosis, but not in those with bilateral stenosis.

• Journal of fish pathology
• /
• v.18 no.3
• /
• pp.269-276
• /
• 2005

The concentrations of quinolones (oxolinic acid; OXA, norlloxacin: NRF & ciprofloxacin: CPF) after oral administration of single doses (20 mg/kg B.W.) were investigated in carp (Cyprinus carpio) kept in freshwater at 20-23$^{\circ}C$. The distribution of the drug was studied after treatment. At points timed, from 1 h to 96 hrs after administration, blood (B), liver (L), kidney (K) and muscle (M) from 5 individuals in each group were collected for analyse with microbiological bioassay method. The peak concentrations were measured at 8 h (L), 12 h (B and K) and 24 h (M) after administration regardless of treated drugs. Considerably high concentrations of CPF (13.8-19.6${\mu}g/m{\ell}$) NRF (11.8-16.9${\mu}g/m{\ell}$) and OXA (10.8-13.9 ${\mu}g/m{\ell}$) were revealed during the 24 h. At the last time point of the experiment (96 h), concentrations of all three quinolones were: OXA, 2.3-6.3 ${\mu}g/m{\ell}$ ; NRF, 3.1-4.5 ${\mu}g/m{\ell}$ ; CPF, 3.0-5.5${\mu}g/m{\ell}$ in samples. The concentrations decreased subsequently, indicating a first rapid redistribution, followed by a slow phase of elimination. The steady state was observed in blood (12-36 h), liver (12-96 h) and muscle (36-96 h) after the initiation of treatment with OXA. Concerning the compartmental concentrations, (L, K. and M/B concentration ratio), the fluctuation of the ratio was founded at different time points, among drugs. For CPF, highest tissue ratios were prolonged in the order of L>K>M (0.65-1.2/0.82-0.93/1.0-1.7) during the experiments. On the other hand, NRF presented L>K>M (0.65-1.3/0.86-1.0) till 24 h, but L>M>K (0.89-1.26) at 36-96 h. OXA showed L>K>M (0.95-2.1) at 1-8 h, M>K>L (0.51-1.0) at 12-36 hand M>L>K (1.0-2.3) at 48-96 h, respectively.

• Korean Security Journal
• /
• no.2
• /
• pp.259-289
• /
• 1999

The Security Industry has dynamic working conditions. So this study intends to find the advisable direction for the reduction of accidents. To achieve the aim, the investigation of documents and the examinations of actual proofs have been done to figure the theoretical background and to see the basic knowledge of security industry. The questionnaire was composed of two question sheets to search real data and actual proofs, with making targets of pure security organization and personnel. The one consists of 9 questions to find the scale and extent of security organizations and the population and character of security personnel, and the other 25 questions in 3 major areas to analyze the causes, the frequency rates, the factors, and the condition of accidents. The period of survey was July 15th to October 15th in 1997 by mail/telephone/interview. The questionnaires were efficiently returned from 102 different organizations including the public security groups of Seoul Metropolitan Police Bureau and so on, with the information of 8,222 persons having worked for Korean Security Industry in 1996. So being based on the reality, some meaningful facts were found, and were compared with the national statistics of the Government. This study is made up of 5 chapters : in the 1st chapter the motivation, the object, the method, the direction and the limitation of the approach were presented ,in the 2nd chapter the theoretical background were inferred ; in the 3rd chapter the collected data of accidents in Korean Security Industry were analyzed and explained on the base of the questionnaires , in the 4th chapter the advisable facts connected with preventing accidents were mentioned ; in the last the conclusion were stated. With the replies of 102 different organizations including the information of 8,222 persons in 1996, the main facts found or analyzed through this study are as follows. Firstly, accident is an unpredictable and occasional event. It occurs to man and/or thing, but the frequency rate of accidents in Korean Government and other Institutes has been calculated and evaluated only in the point of the accident related with man. Secondly, the factors of accidents are firstly relevant to the way preventing accidents in Security Industry in Korea. However the frequency rate is academically calculated and evaluated by at once man(population) and hour(time). But the Government has done the rate only by man(population). This can be improper and inaccurate rates. Thirdly, the confused concept of security is used in Korean Government, academic society, corporation and so on. Therefore the detailed formation of the concept is needed for the development of Security Industry in Korea. Fourthly, security organizations can be classified into 'public security(public law enforcement)' and 'private security' according to its identification, and furthermore 'private security' can be divided into 'facilities-guard service', 'body-guard service', and 'patrol service' according to its major role. Fifthly, in the viewpoint of the number of both organization and population,'facilities-guard service' is centered in Korean 'private security'. According to the analyzed results of the questionnaires in this study, the frequency rate of accidents of Korean Security Industry is 0.43(%) totally in 1996 : 'facilities-guard service' 0.54(%), 'body-guard service' 0.12(%), and 'patrol service' 0.21(%) in 'private security', and 'public security' 0.20(%). With regard to the accident frequency rate of organization and population, 'facilities-guard service' is the highest. The accident frequency rate of population in 'facilities-guard service' organization ranges dispersively from 0.20(%) to 11.11(%). Sixthly, the accidented rate of workers having serviced for under one year is 57.6(%). This can mean that the main factor of accidents in Korean Security Industry is the lack of role-understanding and training/education. And another factor can be found on the time of accident occurrence. Many accidents have been occurred on the relaxed points like as just after lunch and morning rush-hour. Lastly, the major advisable facts related to preventing accidents are as follows : The workers who are over fifty years old in 'facilities-guard service' organization need to be educated for preventing accidents ; It is desirable that the training and education to prevent accidents should be practiced in the time of pre-service ; As the style of accidents and the age of the accidented are not same according to major service area('public security' and 'private security' : 'facilities-guard service', 'body-guard service', and 'patrol service'), the plans to prevent accidents must be different and various. However fracture and bruise are general accidents in Korean Security Industry ; Workers must care about traffic accident and violent fall ; It seems that the grouped working with other two persons will reduce accident occurrence possibility rather than individually single working.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.18 no.1
• /
• pp.33-42
• /
• 2014

Purpose: I-131 scan using High Energy (HE) collimator is generally used. While, Medium Energy (ME) collimator is not suggested to use in result of an excessive septal penetration effects, it is used to improve the sensitivities of count rate on lower dose of I-131. This research aims to evaluate I-131 SPECT/CT image quality using by HE and ME collimator and also find out the possibility of ME collimator clinical application. Materials and Methods: ME and HE collimator are substituted as Siemens symbia T16 SPECT/CT, using I-131 point source and NEMA NU-2 IQ phantom. Single Energy Window (SEW) and Triple Energy Windows (TEW) are applied for image acquisition and images with CTAC and Scatter correction application or not, applied different number of iteration and sub set are reconstructed by IR method, flash 3D. By analysis of acquired image, the comparison on sensitivities, contrast, noise and aspect ratio of two collimators are able to be evaluated. Results: ME Collimator is ahead of HE collimator in terms of sensitivity (ME collimator: 188.18 cps/MBq, HE collimator: 46.31 cps/MBq). For contrast, reconstruction image used by HE collimator with TEW, 16 subset 8 iteration applied CTAC is shown the highest contrast (TCQI=190.64). In same condition, ME collimator has lower contrast than HE collimator (TCQI=66.05). The lowest aspect ratio for ME collimator and HE collimator are 1.065 with SEW, CTAC (+) and 1.024 with TEW, CTAC (+) respectively. Conclusion: Selecting a proper collimator is important factor for image quality. This research finding tells that HE collimator, which is generally used for I-131 scan emitted high energy ${\gamma}$-ray is the most recommendable collimator for image quality. However, ME collimator is also applicable in condition of lower dose, lower sensitive if utilizing energy window, matrix size, IR parameter, CTAC and scatter correction appropriately.