• Journal of Fisheries and Marine Sciences Education
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• v.12 no.1
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• pp.1-10
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• 2000

In order to obtain the fundamental data on the auditory thresholds of fishes for marine ranching, the auditory thresholds of black rock fish Sebastes Schlegeli were measured in the presence of masking noise in the spectrum level range of 73 - 83dB (0dB re $1{\mu}Pa/{\sqrt{Hz}}$) with a classical cardiac conditioning technique. Critical ratios were about 19 - 30dB at 80 - 300Hz and 46 - 54dB at 500 - 800Hz. The ratio increased almost linearly with increasing frequency to 500Hz. The noise spectrum level at the start of masking was about 70dB within the frequency range of 80 - 800Hz excepting 65dB at 300Hz. This suggests that hearing of the black rock fish is masked in the natural environment with the noise spectrum level above 65dB. The sound pressure level of which the signal sound of 100 - 200Hz is recognized by black rock fish under the ambient noise is above 90dB and the critical ratio of them is above 20dB.

• Research in Community and Public Health Nursing
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• v.7 no.2
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• pp.216-228
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• 1996

The purposes of this study were to investigate levels of physical, cognitive, and social functioning in institutionalized elderly. The subjects were 78 residents of a nursing home for the elderly in Pusan. The data were collected from June 24th to July 8th, 1996 using interview and observational method. The structured questionnaires developed by Kim, by Kwon & Park, and by researcher were adopted to measure physical, cognitive, and social function, respectively. The data were analyzed using percentages, means, t test, ANOVA, Pearson correlation coefficient, Cronbach's alpha with the SPSS PC programs. The results were summarized as follows: 1. 34.2% of the subjects had a paralysis, strokes 26.3%, hearing impairment 15.9%, vision impairment 11.8%, mental disturbance 11.8%, cognitive disturbance 10.5%. 2. The mean score on the physical function for the subjects was 73.14, and the items with low functioning levels were 'ascending the stairs', 'bathing' in that order. There was no significant difference in physical function according to the following demographic characteristics: sex, age, and education level. 3. 50.0% of subjects was categorized 'definite dementia', 'questionable dementia' 11.5%, 'definite non-dementia' 38.5%. There was a significant difference in cognitive function according to sex, but were no significant differences according to following demographic characteristics: age and education level. 4. The mean score on the social function for the subjects was 17.60. The items with comparatively high score were in simple activities such as 'enjoying talking with his friends', 'watching TV or listening to the radio', and the items with low score were in complex activities such as 'enjoying a hobby',. 'enjoying a game', 'reading the newspaper or book'. There were no significant differences in social function according to sex and age, but was a significant difference according to education level. 5. Social function was positively correlated with both physical function and cognitive function.

• Research in Community and Public Health Nursing
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• v.4 no.2
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• pp.117-130
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• 1993

There has been a rapid growth in Korea since 1962 because of the success of the 5-year Economic Plan. The number of industrial work and workers has also made had a rapid increase. Consequently, the management of occupational health for the purpose of promoting health in industrial workers is needed especially in the health examination program. The purpose of this study was to analyze the Knowledge, and Attitude among industrial workers of health examination programs. The target population was 402 industrial workers from 4 factories in Kangwon province. A survey was conducted to collect data by a self administered questionnaire from October 29 to November 5. A sixty four item questionnaire was designed to collect data concerning Knowledge, and Attitude of health examination of industrial workers. The data was analyzed by means of percentage, mean, T-test, ANOVA, Pearson's correlation coefficient. The major findings were as follows : 1. The respondents presented the following picture : The male population was 88%. 57% of respondents were age 25-34 years old. 69.4% of respondents were married. 73.4% of respondents were high school graduates. 80.8% of the respondents were working over 48 hours per week. The respondents with over 10 years on the job were 31.9% of the respondents. Health examination were given to the respondents as: pre-employment health examination 90.5%, general health examination 91.5%, and special health examination 31.5%. 2. The Knowledge level was different in health examination items. 80.5% of respondents had knowledge about hearing test, body weight, visually, chest X-ray like simple things. Below 50% of respondents had knowledge of urine test, liver function test, and career history. 3. Attitude status about health examination showed an average score 36.5(median 33) of satisfaction, 26.93(median 21) of importance, 13.84 (median 21) of content, 10.46(median 12 of reliability on health examination results. 4. The level of Attitude on health examination was significantly different than the Knowledge level. 5. The relationship among stated variables such as satisfaction, the perceptions of importance on health, health examination, the result and follow up after health examination were shown to reflect neither positively nor negatively on each other.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.6
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• pp.563-567
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• 2002

Developing base data on luring fish schools into netting position by the use of underwater audible sound on japanese parrot fish Oplegnathus fasciatus found in the coastal waters of Jeju Island, S. Korea. Auditory threshold was determined by the heartbeat condition technique using pure tones coupled with a delayed electric shock. The audible range of japanese parrot fish extended from 80 Hz to 500 Hz with a peak sensitivity at 200 Hz. The mean auditory thresholds at the frequencies of 80 Hz, 100 Hz, 200 Hz,300 Hz and 500 Hz were 104 dB, 95 dB, 91 dB, 99 dB and 113 dB, respectively. As the frequency became higher than 200 Hz, the auditory threshold increased almost linearly with increasing frequency. Critical ratios of fishes measured in the presence of masking noise in the spectrum level range of 69$\~$78 dB (0 dB re 1$\mu$Pa/$\sqrt{Hz}$) ranged from 21 dB to 40 dB at test frequencies. The noise spectrum level at the start of masking was about 70 dB within the test frequency range. The sound pressure level of 100$\~$200 Hz recognized by japanese parrot fish under the ambient noise is above 91 dB and the critical ratio for them is above 21 dB.

• Journal of Veterinary Science
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• v.25 no.3
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• pp.46.1-46.11
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• 2024

Importance: Rabies is a neglected tropical viral disease most often transmitted through the bite of an infected animal. Objective: This study assessed the level of knowledge, attitudes, and practices of the Shone Ttown community toward rabies. Methods: A survey-based cross-sectional study was conducted in Shone town, Ethiopia, from November 2022 to April 2023. Woreda was selected purposefully, while Kebeles and the study populations were selected by simple random sampling. Four hundred and sixteen respondents were interviewed using a semi-structured questionnaire. Results: All respondents had heard about rabies from different sources, with the majority hearing from informal sources (62%). Approximately 51.9%, 0.7%, and 47.4% of individuals were aware of saliva contact, rabid animal bites, and both as means of transmission, respectively. The survey showed that 64.4% of participants knew the 100% fatal nature of rabies once the clinical signs developed, and 35.6% did not. Approximately 51.4% of respondents agreed that killing stray dogs was an effective method for rabies prevention. In this study, 72.6% of the respondents had contact with pets, and 36.8% of the interviewees had vaccinated their dogs. Only the educational level (p = 0.03) was associated with knowledge of the transmission route. Age (p = 0.04) and educational level (p = 0.01) had a statistically significant association with knowledge of the risk of not vaccinating dogs. Conclusions and Relevance: A lack of formal education in the communities, low levels of education, and the majority of respondents acquiring their knowledge from unofficial sources are important contributors to the low levels of awareness.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.11 no.3
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• pp.190-197
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• 2001

Noise-induced hearing loss(NIHL) was the highest rate (43.5%~58.5% from 1996 to 1998) of positive findings through specific medical program in Korea. There were much more NIHL at workers of automobile manufacturing factories than other manufacturing factories. The specific aim of the present study was to determine the noise exposure of automobile press lines, according to their job titles, press line types(auto, semiauto), dosimeter parameters setting. There were a total 11 press lines sampled at a automobile manufacturing company. Among those press lines, 10 press lines were autolines with acoustic enclosure, one semiauto press line was no aucostic enclosure Noise exposure data were sampled for an work shift using noise dosimeter, which recorded both time-weighted average(TWA) and 1-min average. The mean OSHA TWA(Korea TWA with threshold 90) was $80.7dB(A){\pm}4.7dB(A)$ for leader, $82.8dB(A{\pm}4.5dB(A)$ for pallette man, $76.7dB(A){\pm}4.3dB(A)$ for press operators, $76.6dB(A){\pm}5.6dB(A)$ for crane operators, $77.1dB(A){\pm}2.8dB(A)$ for forklift drivers, whereas the mean NIOSH TWA was $88.9dB(A){\pm}1.7dB(A)$ for leader, $89.6dB(A){\pm}2.1dB(A)$ for pallette man, $86.7dB(A){\pm}1.8dB(A)$ for press operators, $88.5dB(A){\pm}2.0dB(A)$ for crane operators, $87.7dB(A){\pm}1.0dB(A)$ for forklift drivers. While L10 for NIOSH TWA samples was 84.8 dB(A) ~ 87.3 dB(A), L10 for OSHA TWA samples was 69.5 dB(A) ~ 77.4 dB(A). L10 means that the TWA for 90% of the samples exceeded L10. Among OSHA TWA(Korea TWA with threshold 90) samples for pallette man, 7.7 % exceeded 90 dB(A), the OSHA permissible exposure level, but OSHA TWA samples for the other job titles didn't. Among NIOSH TWA samples, the samples over 85 dB(A), the NIOSH recommended exposure limit, was 100% (leaders), 83.3 %(operators), 97.4%(palletteman), 100%(forklift drivers), 91.7 %(crane operator). The results of One-way random effects analysis of variance models shows that the difference between job titles was significant by OSHA TWA(p<0.05), but not significant by NIOSH TWA(p>0.05). NIOSH TWA samples were significantly higher than OSHA TWA samples(P<0.05). Regression analysis was used to obtain relationships between OSHA TWA samples and NIOSH TWA samples. In this case the coefficient of determination = 0.90, which shows the high degree association between two methods. Regression equation, NIOSH TWA = 0.552 * OSHA TWA + 42.13 dB(A), shows that if OSHA TWA is known, NIOSH TWA can be predicted by the equation. The mean TWA difference between threshold 80 dBA and 90 dBA was significant(p<0.01). While the TWA noise exposures were 7.7% above the Korea(OSHA) PEL, they were more than 83.3% over NIOSH REL. Automobile workers were exposed to noise level that could be potentially damaging to their hearing. It found that there is approximately 25% excess risk of hearing loss even if a worker is protected to the PEL in according to NIOSH study.

• Journal of Preventive Medicine and Public Health
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• v.22 no.3 s.27
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• pp.355-367
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• 1989

This study examined the physical and mental health factors affecting the industrial accidents of 142 injured and 1,212 uninjured workers in the shipbuilding industry from 1986 to 1988. The results acquired from the Todai Health Index (THI) and from analysis of the health examination were as follows: 1. Among the personal characteristics of the workers, the educational level of injured workers was significantly lower than that of the uninjured workers. 2. Among the physical characteristics, vision and $R\ddot{o}hrer$ Index of the injured workers were lower than those of the uninjured workers, and the difference was statistically significant. On the other hand, the differences in height, weight, hearing function, hematocrit, blood pressure, urine test, and X-ray findings were not statistically significant between the injured and uninjured workers. 3. The score of the THI questionnaire on the physical and mental health of the injured workers was higher than that of the uninjured workers, and the difference was statistically significant. 4. Form the THI score, the industrial workers had complained more about mental health than physical health and there was a statistically singinficant relation with the industrial accidents. 5. The relative risk expressed in terms of the odds ratio was 2.9 for poorer vision, 2.7 for a lower educational level, 2.2 for a higher THI score and 1.6 for overdrinking. 6 Educational level, vision, and the THI score were selected as significant factors influencing industrial accidents based on a log-linear model. According to the results of this model by logistic analysis, the odds ratio of industrial accidents was 1.8 for a lower educational level, 1.7 for poorer vision, and 1.6 for a higher THI score. 7 By event history analysis with the dependent variable as the duration of work at the time of the industrial accident, educational level, age, $R\ddot{o}hrer$ Index and THI score were the statistically significant variables selected, and the hazard rate of industrial accident occurrence was 0.24 for a lower educational level, 0.92 for age, 0.99 for a lower $R\ddot{o}hrer$ Index and 2.72 for a higher THI score. As we have seen, educational level and THI score were the most significant factors affecting the hazard rate of industrial accidents. Vision, $R\ddot{o}hrer$ Index, age, and drinking behavior were also statistically significant variables influencing industrial accidents. Therefore, in order to prevent industrial accidents, it is necessary to establish a health management plan for industry which can objectively evaluate not only the physical but also the mental health of the workers. If we use this type of study as a prospective study design, we can determine the relative risk of physical and mental health factors on industrial accidents. Furthermore, it is expected that this type of study will provide workers at high risk with more precise basic data for a health managment plan for industrial accident prevention.

• Phonetics and Speech Sciences
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• v.4 no.3
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• pp.129-136
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• 2012

Korean alveolar fricatives are late-developing speech sounds. Most previous research on phonemes used individual words or pseudo words to produce sounds, but word-level phonological analysis does not always reflect a child's practical articulation ability. Also, there has been limited research on articulation development looking at speech production by grammatical morphemes despite its importance in Korean language. Therefore, this research examines the articulation development and phonological patterns of the /s/ phoneme in terms of morphological types produced in children's spontaneous conversational speech. The subjects were twenty-two typically developing 3- and 4-year-old Koreans. All children showed normal levels in three screening tests: hearing, vocabulary, and articulation. Spontaneous conversational samples were recorded at the children's homes. The results are as follows. The error rates decreased with increasing age in all morphological contexts. Also, error percentages within an age group were significantly lower in lexical morphemes than in grammatical morphemes. The stopping of fricative sounds was the main error pattern in all morphological contexts and reduced as age increased. This research shows that articulation performance can differ significantly by morphological contexts. The present study provides data that can be used to identify the difficult context for articulatory evaluation and therapy of alveolar fricative sounds.

• Journal of Biomedical Engineering Research
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• v.22 no.3
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• pp.241-247
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• 2001

ABR(auditory brainstem response) is one of the audiometry which measures objective hearing threshold level by acquiring electric evoked potentials emanated from auditory nerve system responding to an auditory stimulation. However, the obtained potentials which are largely interfered by power line noise, have extremely low SNR, thus ensemble average algorithm is generally used. The purpose of this study was to investigate the effect of iteration number in ensemble average on the reduction of the power line noise. The power line noise was modeled to be a 60 Hz sinusoidal signal and the energy of the modeled signal was calculated when it was averaged. It was verified by simulation that the energy had the periodic zero points for each stimulation rate, and 60 Hz signal induced by the power line was applied to the developed ABR system to confirm that the period of zero energy point was the same with that of the simulation. By the properly selected iteration number, power line noise could be reduced and more reliable ABR could be acquired.

• Journal of Information Technology Applications and Management
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• v.15 no.1
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• pp.261-270
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• 2008

Wireless Mesh Networks (WMNs) have emerged as one of the new hot topics in wireless communications. WMNs have been suggested for use in situations in which some or all of the users are mobile or are located in inaccessible environments. Unconstrained transmission in a WMN may lead to the time overlap of two or more packet receptions, called collisions or interferences, resulting in damaged useless packets at the destination. There are two types of collisions; primary collision, due to the transmission of the stations which can hear each other, and hidden terminal collision, when stations outside the hearing range of each other transmit to the same receiving stations. For a WMN, direct collisions can be minimized by short propagation and carrier sense times. Thus, in this paper we only consider hidden terminal collision while neglecting direct collisions. To reduce or eliminate hidden terminal collision, code division multiple access (CDMA) protocols have been introduced. The collision-free property is guaranteed by the use of spread spectrum communication techniques and the proper assignment of orthogonal codes. Such codes share the fixed channel capacity allocated to the network in the design stage. Thus, it is very important to minimize the number of codes while achieving a proper transmission quality level in CDMA WMNs. In this paper, an efficient heuristic code assignment algorithm for eliminating hidden terminal collision in CDMA WMNs with general topology.