• Journal of agricultural medicine and community health
• /
• v.45 no.2
• /
• pp.69-78
• /
• 2020

Purpose: This study was conducted to provide the results of the epidemiological investigation for outbreak of Clostridium perfringens enteritis among students at a college in Sejong City. Methods: This investigation was performed between May 25 and May 28, 2018. The Sejong City public health authority received a complaint which was about 40 university students experienced vomiting or diarrhea. We immediately set up an epidemiological investigation team and conducted a field epidemiological investigation. Results: The overall incidence was 86 out of 153 (56.2%). The estimated risk exposure time was 12 o'clock on the previous day, and the cause was contaminated during distribution and storage of the lunch box provided for lunch on the day of the athletic competition, with 13 hours of average incubation period. The outbreak was closed on May 28, and the identified pathogen was Clostridium perfringens. Conclusions: It was proposed that food poisoning by Clostridium perfringens was likely and contaminated during group meal.

• Journal of Broadcast Engineering
• /
• v.19 no.4
• /
• pp.439-452
• /
• 2014

This paper suggests the method to extend service area by using the transmit offset delay in T-DMB single frequency network (SFN). In general, synchronization of the transmit time of all site can be done by using the reference clock of GPS, which dose not reflect the details geographical characteristics and transmit specifications of each site. Applying the site-specific transmit offset delay, we could extend the service area of SFN T-DMB. Applying the transmit offset delay, it is found that the signal quality in the region of weak receive field strength was improved and upto 4~8 km service area expansion was achieved by satisfying the minimum field strength ($45dB{\mu}V/m$) recommended by the Korea Communications Commission (KCC). Site-specific offset delay was calculated considering the geographic service area characteristics, distribution of electric field strength between neighboring sites and site-specific service target area. Experiments were carried out in order to analyze impact of calculated offset delay on the T-DMB SFN and also to confirm that the offset delay extends T-DMB service coverage. The experiment was done in metropolitan T-DMB service areas.

• Journal of Trauma and Injury
• /
• v.30 no.3
• /
• pp.75-79
• /
• 2017

Purpose: Although trauma is the most common cause of death under age 18, Korean national pediatric trauma data has lack of clinical data. This study is to prepare manpower resources, equipment, and make a correct policy decision on pediatric trauma victims Methods: The study enrolled 528 patients under age 16 with traumatic injury visited Wonju Severance Christian Hostpital Trauma Center, from February 12, 2015 to December 31, 2016. We analyzed the distribution of gender, age, place and time of the accident, injury mechanism, injury severity, and injured organ by medical record. Results: The major injury mechanisms were blunt injury in 485 (91.90%), penetrating injury in 27 (5.10%), burn in 13 (2.50%), near drowning in 2 (0.40%), and foreign body ingestion in 1 (0.20%). Ninety-seven (18.4%) patients were injured at home and 67 (12.7%) patients were injured at school. The overall mortality rate was 1.13% (n=6). 5 mortalities were related to automobile accident and one was fall down. Mean Injury Severity Score (ISS) was 4 (2, 8). No statistical significance was observed in the mean ISS between each age group. The peak time of accident occurrence was between 16 and 17 o'clock. The mean ISS was higher in blunt injury group than penetrating injury with statistical significance ($6.50{\pm}7.60$ vs. $3.00{\pm}8.10$; p<0.05). The most common injury site was upper extremity. Mean ISS was highest in thorax injury. However, mean ISS of thorax injury was higher with statistical significance only compared with face, neck and upper extremity injury. Conclusions: We reported our pediatric trauma patients data of our hospital level I trauma center, which is the only one level I trauma center of Gangwon Province. These data is useful to prevent and prepare for pediatric trauma.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.34 no.11A
• /
• pp.882-890
• /
• 2009

In this paper, we describe a compensation method that can be used for the situation where Loran receivers lose their phase lock to the received Loran signals when Loran signals are employed for the synchronization of national infrastructures such as telecommunication networks, electric power distribution and so on. In losing the phase lock to the received signals in a Loran receiver, the inner oscillator of the receiver starts free-running and the performance of the timing synchronization signals which are locked to the oscillator's phase is very severly degraded, so the timing accuracy under 1 us for a Primary Reference Clock (PRC) required in the International Telecommunications Union (ITU) G.811 standard can not be satisfied in the situation. Therefore, in this paper, we propose a method which can compensate the phase jump by using a compensation algorithm when a Loran receiver loses its phase lock and the performance evaluation of the proposed algorithm is achieved by the Maximum Time Interval Error (MTIE) of the measured data. From the performance evaluation results, it is observed that the requirement under 1 us for a PRC can be easily achieved by using the proposed algorithm showing about 0.6 us with under 30 minutes mean interval of smoothing with 1 hour period when the loss of phase lock occurs.

• Clinical and Experimental Pediatrics
• /
• v.48 no.10
• /
• pp.1061-1067
• /
• 2005

Purpose : We studied a clinical analysis of pediatric patients who visited the emergency medical center of Yeungnam University Hospital to compare the characteristics of pediatric emergency patients after year 2000 with the previous studies. Methods : We reviewed 7,034 children under the age of 15 years who visited the emergency medical center of Yeungnam University Hospital during the 2 year period from January 2001 to December 2002, and then we performed a clinical and statistical analysis. We analyzed the pediatric patients according to gender, age, season, day of the week, time of the visit, the disease classification and the final disposition of the patients. Results : Among the patients who visited the emergency room, 15.6% of the total emergency patients were under the age of 15. The male to female ratio was 1.6 : 1. Among the 7,034 pediatric patients, the most common age group was between 1 year and under 3 years of age(26.9%). The peak seasonal incidence was early summer and spring, especially during June(11.2%) and May(10.6 %). The peak incidence day of the week was Sunday(24.8%) and the peak time when the emergency pediatric patients visited the emergency room was between 20 and 24 o'clock(28.8%). The distribution of diseases, according to ICD-10 system, were injury and poisoning(30.4%), diseases of the respiratory system(22.8%), and diseases of the digestive system(14.6%). 30% of total pediatric patients were admitted to the hospital. Conclusion : After year 2000, as compared with the previous studies, the proportions of emergency pediatric patients has decreased. The distribution of diseases was not much different from the previous studies and the proportions of non-urgent diseases, such as acute nasopharyngitis or acute gastroenteritis, were still high. These result have come about due to the declining birth rate and changes of the medical system in Korea.

• Journal of the Korean association of regional geographers
• /
• v.2 no.1
• /
• pp.133-150
• /
• 1996

This study is to clarify the market cycle of travelling merchants and the spatial behavior of consumer's commodity purchasing. its reasons and purchasing region of each commodity in Chongsan of Chongsan Myun(village) periodic markets, that is one of the lowest central places in Okchon county. The data used are the results of interviews with 58 travelling merchants on June 22 and July 17, 1994, and questionaire survey taken to parents of students of Chongsan middle school of Chongsan Myun in Okchon county. Study area is typical agricultural regions taking the role of central places to provide rural service and is comparatively important periodic markets. Some of findings are summarized as follows: (1) Until 1980's. appearance of closed periodic markets is caused by the population decrease in rural region, income increase, and rising of living level according to the Five Years Planning of Economic Development, appearance of chain stores of agricultural co-coperative and of supermarkets,. changes in distribution mechanisim by increasing consignment volume of agricultural products through agricultural co-coperative, and the development of transportation in Okchon county. These, too, became the reasons for the decline of the Chongsan periodic markets in Okchon county. (2) Most of the travelling merchants visiting the Chongsan periodic markets are in their 50's of age, and they sell the miscellaneous commodities and agricultural products. And about one-fourths of travelling merchants reside in regions with periodic markets and in Okchon of higher order central places. (3) Travelling routes visting periodic markets can be simplified to five types. Major types of travelling routes are Chongsan periodic market$\rightarrow$Wonnam$\rightarrow$Boun, and Chongsan periodic market$\rightarrow$Yungdong$\rightarrow$Yongsan. The patterns of travelling merchants visiting periodic markets are classified into the type of everyday visiting of periodic markets over three days of five days from merchant's residence to market, and the type of merchants or consumers visiting one day's of five days. On days that travelling merchants don't visit periodic markets they purchase the commodities in Seoul, Taejon and Chongju. (4) Consumers who use periodic markets are from thirties to fifties years of age and most of them are employed in agriculture. Consumers visit periodic markets on foot or by bus, and visit two or three times in a month, and mainly purchase the commodities for one or two hours from about ten o'clock in the morning. (5) Consumers purchase the necessaries of life in periodic markets, and other commodities are purchased in Taejon city, Youngdong, and Boun Eup(town). But consumers purchase the goods(convenience goods, shopping goods, and specialied goods) largerly in Chongsan, because additional expense and disadvantage after service with poor transportation service for purchased goods in others regions. Therefore, the hierarchies of central places by the consumer's purchasing behaviour can not be seem in dewellers in Chongsan and Chongseong Myun.