• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.5 no.3
• /
• pp.101-109
• /
• 2012

Because the installation problem of parabola antenna that is tilted to 45 degree when this antenna is installed at the area of middle latitude, the study on planar antenna in place of parabola antenna is made rapid progess. Especially, The development of the planar antenna for VSAT is needed depending on the increased Ka-band satellite communications. In this paper, in order to meet with these performances, an array antenna consisting of the vertical polarized waveguide longitudinal slots based on the leaky-wave mode of traveling wave antenna is proposed. Especially, for the lower sidelobe level, the design method of the radiation power distribution control using the different slot widths is proposed. An array antenna consisting of 32 leakywave waveguide antennas is showing 35.16 dBi of gain, 2.5 degree of beamwidth at azimuth, below than -30 dB of sidelobe level, 45.8 degree of beam tilt angle in center frequency 30.2 GHz.

• Journal of Korean Society of Forest Science
• /
• v.101 no.1
• /
• pp.96-103
• /
• 2012

In this study, we used HARVEST, a timber management strategy assessment tool, to evaluate alternative forest planning strategies on spatial pattern of cutting blocks. We applied the tool to the Gwangreung Experimental Forest (GEF) as a case study. The harvest schedules developed for GEF using a linear programming model was used to assess spatial patterns of cutting blocks under different management constraints. The results show that the allowable maximum harvest size largely affects the number, size, and distribution of cutting blocks. We also found that spatial dispersion methods and adjacency constraints could be used as an effective means to control spatial allocation of cutting blocks in order to meet certain forest ecosystem management goals.

• Korean Journal of Microbiology
• /
• v.47 no.4
• /
• pp.323-327
• /
• 2011

Fecal specimens from acute gastroenteritis in Seoul from 2009 to 2010 were collected and then tested for the presence of Group A Rotavirus by ELISA. Among a total of 1,916 samples investigated, 354 samples (18.4%) were positive. The predominant genotypes of positive samples were confirmed as P6G[4] (35%), P8G[3] (28%), P8G[1] (24%), P4G[2] (10%), P8G[9] (3%), respectively. Among a total of 70 ground water samples investigated, 2 samples (2.8%) were positive. The genotypes of positive samples were confirmed as P8G[3] (100%). By this molecular investigation, genotypic distribution associated with rotavirus will be used for control and prevention of rotavirus related diseases.

• Parasites, Hosts and Diseases
• /
• v.58 no.4
• /
• pp.431-443
• /
• 2020

Echinostoma mekongi n. sp. (Digenea: Echinostomatidae) is described based on adult flukes collected from humans residing along the Mekong River in Cambodia. Total 256 flukes were collected from the diarrheic stool of 6 echinostome egg positive villagers in Kratie and Takeo Province after praziquantel treatment and purging. Adults of the new species were 9.0-13.1 (av. 11.3) mm in length and 1.3-2.5 (1.9) mm in maximum width and characterized by having a head collar armed with 37 collar spines (dorsal spines arranged in 2 alternative rows), including 5 end group spines. The eggs in feces and worm uterus were 98-132 (117) ㎛ long and 62-90 (75) ㎛ wide. These morphological features closely resembled those of Echinostoma revolutum, E. miyagawai, and several other 37-collar-spined Echinostoma species. However, sequencing of the nuclear ITS (ITS1-5.8S rRNA-ITS2) and 2 mitochondrial genes, cox1 and nad1, revealed unique features distinct from E. revolutum and also from other 37-collar-spined Echinostoma group available in GenBank (E. bolschewense, E. caproni, E. cinetorchis, E. deserticum, E. miyagawai, E. nasincovae, E. novaezealandense, E. paraensei, E. paraulum, E. robustum, E. trivolvis, and Echinostoma sp. IG). Thus, we assigned our flukes as a new species, E. mekongi. The new species revealed marked variation in the morphology of testes (globular or lobulated), and smaller head collar, collar spines, oral and ventral suckers, and cirrus sac compared to E. revolutum and E. miyagawai. Epidemiological studies regarding the geographical distribution and its life history, including the source of human infections, remain to be performed.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.53 no.3
• /
• pp.286-292
• /
• 2017

The Coastal VTS will be continuously constructed to prevent marine traffic accidents in the coastal waters of the Republic of Korea. In order to provide the best traffic information service to the ship operator, it is important to understand the navigation risk factor. In this study, we analyzed the navigational hazards of Gunsan coastal area where the coastal VTS will be constructed until 2020. For this purpose, major traffic flows of merchant ships and density of vessels engaged in fishing were analyzed. This study was conducted by Automatic Identification System (AIS) and Vessel Pass (V-PASS) data. The grid intervals are 10 minute ${\times}$ 10 minute (latitude ${\times}$ longitude) based on the section of the sea. A total of 30 sections were analyzed by constructing a grid. As a result of the analysis, the major traffic flows of the merchant vessels in the coastal area of Gunsan were surveyed from north to south toward Incheon, Pyeongtaek, Daesan, Yeosu, Pusan and Ulsan, and from east to west in the port of Gunsan Port, 173-3, 173-6, 173-8, 183-2, 183-5, 183-8, 183-3, 184-1 and 184-2. As a result of the study, the fishing boats in Gunsan coastal area mainly operated in spring and autumn. On the other hand, the main traffic flow of merchant ships and the distribution of fishing vessels continue to overlap from March to June, so special attention should be paid to the control during this period.

• Parasites, Hosts and Diseases
• /
• v.56 no.6
• /
• pp.531-543
• /
• 2018

Historically, Plasmodium vivax malaria has been one of the most highly endemic parasitic diseases in the Korean Peninsula. Until the 1970s, vivax malaria was rarely directly lethal and was controlled through the Korean Government Program administered by the National Malaria Eradication Service in association with the World Health Organization's Global Malaria Eradication Program. Vivax malaria has re-emerged in 1993 near the Demilitarized Zone between South and North Korea and has since become an endemic infectious disease that now poses a serious public health threat through local transmission in the Republic of Korea. This review presents major lessons learned from past and current malaria research, including epidemiological and biological characteristics of the re-emergent disease, and considers some interesting patterns of diversity. Among other features, this review highlights temporal changes in the genetic makeup of the parasitic population, patient demographic features, and spatial distribution of cases, which all provide insight into the factors contributing to local transmission. The data indicate that vivax malaria in Korea is not expanding exponentially. However, continued surveillance is needed to prevent future resurgence.

• Journal of the Korea Society of Computer and Information
• /
• v.25 no.12
• /
• pp.127-134
• /
• 2020

Recently, Harmful sites, including pornographic videos, drugs, personal information and hacking tool distribution sites, have caused serious social problems. However, due to the nature of the Internet environment where anyone can use it freely, it is difficult to control the user effectively. And the site operator operates by changing the domain to bypass the blockage. Therefore, even once identified sites have low persistence. In this paper, we propose multi-channel domain tracking technology, a technique that can effectively track changes in the domain addresses of harmful sites, including the same or similar content, by tracking changes in these harmful sites. Proposed technology is a technology that can continuously track information in a domain using OSINT technology. We tested and verified that the proposed technology was effective for domain tracking with a 90.4% trace rate (sensing 66 changes out of 73 domains).

• Journal of the FoodService Safety
• /
• v.2 no.2
• /
• pp.97-102
• /
• 2021

The purpose of this study was to investigate the effect of developing and continuously providing on-line hygiene education programs on the improvement of hygiene conditions in children's cafeterias. As a result of the 2020 sanitation and safety checklist analysis, 6 items (personal hygiene, separate use, clean ventilation, temperature control of refrigerators, country of origin, food distribution) were derived and on-line hygiene education programs for each of 6 items were produced. ① Customized educational materials and self-inspection checklists were provided to 208 children's cafeterias. After that, educational videos were provided through Kakao Talk twice a week for 6 months, and they were made available for viewing at any time through YouTube upload, ③ Kakao Talk Through this, a quiz related to the educational video was conducted to give feedback for interaction with the cook. As a result of analyzing the total hygiene and safety checklist score of all registered facility catering centers by visit order, in 2020 it was 82.8 points/100 points, but in 2021, it was 84.2 points (1st round), 89.3 points (2nd round), 91.4 points (3 points) The score improved significantly (p<0.001) as the on-line hygiene education program continued. As a result, significant (p<0.001) changes were observed in the items of 'Knife, chopping board' and 'Sanitation clothes, sanitary hat, sanitary shoes, apron, and sanitary gloves', confirming a clear improvement effect. Therefore, it is considered that the on-line hygiene education program will play a positive role in showing a lasting effect on improving hygiene management in children's cafeterias.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.17 no.1
• /
• pp.125-132
• /
• 2022

In this paper, we presented a cart which can automatically transport loads to the distribution center of the appointed indoor place, based on Raspberry pi 4. It can recognize the obstacles by using the ultrasonic sensors so that it prevents the collision and takes a detour. Further, we entered the direction control code in the RFID. It has installed at important points such as the intersections of the destinations, so that if the RFID reader of the cart senses the RFID, the cart would stop or change the direction. After the transportation, if the load cell(weight sensor) recognizes that the baggage is unloaded, the cart returns to the initial point and would be retrieved. Therefore, we embodied the transportation cart which reduces the use of manpower and solves the problems conveniently across the transportation strategies.

• Korean Journal of Audiology
• /
• v.24 no.2
• /
• pp.71-78
• /
• 2020

Background and Objectives: Currently limited information is available on speech stimuli processing at the subcortical level in the recipients of cochlear implant (CI). Speech processing in the brainstem level is measured using speech-auditory brainstem response (S-ABR). The purpose of the present study was to measure the S-ABR components in the sound-field presentation in CI recipients, and compare with normal hearing (NH) children. Subjects and Methods: In this descriptive-analytical study, participants were divided in two groups: patients with CIs; and NH group. The CI group consisted of 20 prelingual hearing impairment children (mean age=8.90±0.79 years), with ipsilateral CIs (right side). The control group consisted of 20 healthy NH children, with comparable age and sex distribution. The S-ABR was evoked by the 40-ms synthesized /da/ syllable stimulus that was indicated in the sound-field presentation. Results: Sound-field S-ABR measured in the CI recipients indicated statistically significant delayed latencies, than in the NH group. In addition, these results demonstrated that the frequency following response peak amplitude was significantly higher in CI recipients, than in the NH counterparts (p<0.05). Finally, the neural phase locking were significantly lower in CI recipients (p<0.05). Conclusions: The findings of sound-field S-ABR demonstrated that CI recipients have neural encoding deficits in temporal and spectral domains at the brainstem level; therefore, the sound-field S-ABR can be considered an efficient clinical procedure to assess the speech process in CI recipients.