• Journal of Navigation and Port Research
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• v.36 no.8
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• pp.625-630
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• 2012

The DGNSS Central Office operates 17 DGNSS reference stations. Compared to the other DGNSS sites, the TEQC data quality of some sites is poorer. In this study, we tried to find out the causes that degrade the quality of GPS data for the purpose of improving the signal quality of the DGNSS stations. We selected the Chungju station that is the one of those stations with bad data quality. Through the on-site visit, we found that there is no signal-blocking obstacles. In addition to site surveys, we conducted two experiments; simultaneous observation considering environmental factors and comparison test through equipment replacements to check the malfunctioning of GPS equipments. In the simultaneous test results, we realized that environmental factors do not induce any bad effects on the data quality. In equipment replacement experiments, we confirmed that the data quality is of excellent quality when the test receiver was used instead of the original one installed at the site. When we replaced the antenna instead of the receiver, the data quality was bad. Through those two experiments, we concluded that the receiver is the main factor that degrades the signal quality.

• Journal of Navigation and Port Research
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• v.44 no.3
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• pp.253-263
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• 2020

In the case of government policies related to the Arctic Ocean, there is a "Northern Sea activity promotion basic plan" presented by the Ministry of Maritime Affairs and Fisheries, but it is difficult to adjust the timing of the policy enforcement and consider the importance of policies because no concrete order of enforcement of policies or weight has been presented by the government. In view of this, the purpose of this study was to estimate the priorities of the government's Arctic policies. Additionally, this study also presents priorities for "support measures" and "foreign cooperation measures" for the smooth implementation of Arctic policies. As for the methodology of this study, the CFPR (Consistent Fuzzy P reference Relations) method, which can comprehensively estimate expert opinions, was applied. According to the results of the analysis, the most important Arctic policy of the government was shown to be "Cooperation for Shipping and Logistics, such as Pioneering Northern Sea Routes" (0.087), followed by "Fostering Professional Manpower" (0.086), and "P reparing Institutional Foundation and Blueprint" (0.085). The results of this study have implications for the establishment of Arctic Ocean-related policies by policymakers as well as authorities.

• The KIPS Transactions:PartA
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• v.16A no.5
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• pp.357-368
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• 2009

Mobile IP storage has been proposed to overcome storage limitation in the flash memory and hard disks. It provides almost capacity-free space for mobile devices over wireless IP networks. However, battery lifetime of the mobile devices is reduced rapidly because of power consumption with continuous use of a WLAN device when multimedia contents are being streamed through the mobile IP storage. This paper proposes an energy-efficient WLAN device power control technique for streaming multimedia contents with the mobile IP storage. The proposed technique consists of a prefetch buffer input/output module, a WLAN device power control module, and a reconfigurable prefetch buffer module. Besides, it adaptively determines the size of the prefetch buffer according to a quality of the multimedia contents, and it dynamically controls the power mode of the WLAN device on the basis of power on-off operations while streaming the multimedia contents. We evaluate the performance of the proposed technique on a PXA270-based mobile device that employs the embedded linux 2.6.11, Intel iSCSI reference codes, and a WLAN device. Extensive experiments reveal that the proposed technique can save the energy consumption of the WLAN device up to 8.5 times with QVGA multimedia contents, as compared with no power control.

• Journal of Veterinary Clinics
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• v.32 no.6
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• pp.477-480
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• 2015

A total number of 100 fecal samples were examined for the presence of Giardia intestinalis infection in dogs using a Giardia ELISA kit (SNAP$^{(R)}$ test, IDEXX Laboratories, Inc., Westbrook, ME). 49 males and 51 females were examined for a G. intestinalis infection in Daejeon and Chungnam area of South Korea. The overall positive rate of G. intestinalis infection was 12.00%. G. intestinalis infection resulted to be more prevalent in males (12.24%) than in females (11.76%), and in symptomatic dogs (18.18%) than in asymptomatic dogs (11.54%). There were no significant differences between the two groups. 19.60% being found in the < 2-year-old group, 4.08% in the over 2 year-old group. $X^2$ analysis revealed a significantly higher prevalence (p < 0.05) in the < 2-year-old group than in the other, and a significantly higher prevalence in dogs kept in a shared kennel (36.00%, p < 0.001). This study is the first survey of G. intestinalis infection prevalence in South Korea according to life style (particularly between dogs kept in a shared kennel and that of dogs kept separately) using an ELISA kit, and this study is expected to provide a useful reference for clinicians and breeders.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.2
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• pp.100-106
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• 2012

Objectives: Diazinon is an insecticide which acts as a contact stomach and respiratory poison, and used throughout the world to control a wide range of sucking and chewing insects and mites on a range of crops. In this study, the airborne diazinon levels were measured for farmers, pest control operaters, landscapers, and agricultural chemicals sellers, and an assessment of the health risk to the workers was presented. The exposure scenario was based on the route of inhalation and skin absorption. The "OSHA Method No. 62" was used to sample and measure the airborne diazinon levels. The skin wipe method was applied to measure the level of the diazinone exposure through the skin. For the determination of exposure scenario, the exposure factors were surveyed for the daily average inhalation rate and the exposure period and frequency and time of diazinone as well as the body weight and lifetime of the workers. The median values of exposure frequency and exposure time were selected after evaluating the validity of those. Methods: The highest level of the diazinon exposure in the air was $107.21ug/m^3$ in farmers, followed by $93.53ug/m^3$ in landscapers, at $31.40ug/m^3$ in pest control operators, and $1.04ug/m^3$ in agricultural chemical seller. The amount of skin absorption was the highest in farmers at 63.39 ug/day, followed by landscapers at 10.47 ng/day, pest control operaters at 4.26 ng/day, and agricultural chemicals sellers at 0.34 ng/day. The hazardous indices calculated using toxicological reference value were 2.79 for pest control operaters, 0.41 for landscapers, 0.07 for agricultural chemicals sellers, and 0.06 for farmers. Conclusions: While the farmers were exposed to the high levels of diazinon through the air and skin, the pest control operaters, landscapers and agricultural chemicals sellers have more the diazinon hazards than the farmer based on the risk assessment in this study.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.27 no.1
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• pp.38-45
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• 2017

Objectives: Radon may be second only to smoking as a cause of lung cancer. Radon is a colorless, tasteless radioactive gas that is formed via the radioactive decay of radium. Therefore, radon levels can build up based on the amount of radium contained in construction materials such as phospho-gypsum board or when ventilation rates are low. This study provides our findings from evaluation of radon gas at facilities and offices in an industrial complex. Methods: We evaluated the office rooms and processes of 12 manufacturing factories from May 14, 2014 to September 23, 2014. Short-term data were measured by using real-time monitoring detectors(Model 1030, Sun Nuclear Co., USA) indoors in the office buildings. The radon measurements were recorded at 30-minute intervals over approximately 48 hours. The limit of detection of this instrument is $3.7Bq/m^3$. Also, long-term data were measured by using ${\alpha}-track$ radon detectors(${\alpha}-track$, Rn-tech Co., Korea) in the office and factory buildings. Our detectors were exposed for over 90 days, resulting in a minimum detectable concentration of $7.4Bq/m^3$. Detectors were placed 150-220 cm above the floor. Results: Radon concentrations averaged $20.6{\pm}17.0Bq/m^3$($3.7-115.8Bq/m^3$) in the overall area. The monthly mean concentration of radon by building materials were in the order of gypsum>concrete>cement. Radon concentrations were measured using ${\alpha}-track$ in parallel with direct-reading radon detectors and the two metric methods for radon monitoring were compared. A t-test for the two sampling methods showed that there is no difference between the average radon concentrations(p<0.05). Most of the office buildings did not have central air-conditioning, but several rooms had window- or ceiling-mounted units. Employees could also open windows. The first, second and third floors were used mainly for office work. Conclusions: Radon levels measured during this assessment in the office rooms of buildings and processes in factories were well below the ICRP reference level of $1,000Bq/m^3$ for workplaces and also below the lower USEPA residential guideline of $148Bq/m^3$. The range of indoor annual effective dose due to radon exposure for workers working in the office and factory buildings was 0.01 to 1.45 mSv/yr. Construction materials such as phospho-gypsum board, concrete and cement were the main emission sources for workers' exposure.

• 한국해양학회지
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• v.22 no.2
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• pp.57-62
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• 1987

The Markov chain properties of the sea surface temperature (SST) anomalies, namely, the dependency of the monthly SST anomaly on that of the previous month, are studied based on the SST data for 28years(1957-1984) at 5 stations in the southeastern coast of Korea. Wi classified the monthly SST anomalies at each station into the low, the normal and the high state, and computed transition probabilities between SST anomalies of two successive months The standard deviation of SST anomalies at each station is used as a reference for the classification of SST anomalies into 3states. The transition probability of the normal state to remain in the same state is about 0.8. The transition probability of the high or the low states to remain in the same state is about one half. The SST anomalies have almost no probability to transit from the high (the low) state to the low (the high) state. Statistical tests show that the Markov chain properties of SST anomalies are stationary in tine and homogeneous in space. The multi-step Markov chain analysis shows that the 'memory' of the SST anomalies at the coastal stations remains about 3 months.

• Korean Journal of Ecology and Environment
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• v.48 no.2
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• pp.77-85
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• 2015

Siniperca scherzeri is major target species for restocking and restoration project as it is one of the economic species in South Korea. In this study, to investigate their ecological characteristics movement pattern and habitat characteristic of S. scherzeri were analyzed using radio telemetry. Three specimens released during spawning season, moved more than 10 km toward upstream from the release site. Whereas the remains released after spawning season, settled within 400 m of their release site except two specimens (Ss 11, 3.2 km; Ss, 15, 1.4 km). One of possible reason of upstream movement during spawning season is reproduction. The conditions of their settlement area is similar with reference conditions of their spawning ground. S. scherzeri were mainly detected near the edge of the water, and it may related with the facts that rocks are mainly located at the edge of the water and S. scherzeri prefers rocks for their shelter. AMD (Accumulated movement distance) positively related with body weight and condition factor K, but no significant relationship was identified with gender and total length. Daily movement boundary of S. scherzeri was $214.94m^2{\sim}3,257.19m^2$, and their movement was restricted near the edge of the water. The results of this study could be useful to restocking and restoration.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.4
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• pp.406-413
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• 2019

This study was undertaken to investigate the distribution of human papillomavirus (HPV) subtypes and cervical lesions in Busan. Furthermore, the cytological and histological findings of cervical lesions were compared to determine the usefulness of the currently released vaccines. HPV subtypes of 2,130 patients who visited Haeundae Paik Hospital between January 2013 and March 2016 were analyzed by the HPV 9G DNA chip. Liquid-based cytological examination was performed, and subtypes were classified according to the 2001 guidelines of The Bethesda System. Biopsy or hysterectomy specimens were subjected to hematoxylin and eosin staining for histological examinations. Of the total 2,130 cases, 1,254 (58.9%) were positive for HPV, and 876 (41.1%) were negative. Of these, 152 (7.1%), 97 (4.6%) and 80 (3.8%) were identified as HPV 16, 68 and 56, respectively. Of the 329 cases encompassing the above three HPV subtypes, histopathological analysis diagnosed 155 (47.1%) cases with CIN2 or higher grade. Notably, the occurrences of HPV subtypes 16, 68, 56, 58 and 51 were most frequently diagnosed in Busan. Further analysis revealed that administration of Gardasil^Ⓡ 9, the currently available vaccine in the market, exerts no protection against subtypes 68, 59 and 51. This study aims to provide an important reference for future HPV vaccination programs in Busan.

• Korean journal of food and cookery science
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• v.22 no.5 s.95
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• pp.609-616
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• 2006

The effects of purified licorice (Glycyrrhiza uralensis) extract (PLE) as a sugar substitute on kimchi quality were evaluated by investigating acid formation, growth of lactic acid bacteria, sensory properties, and volatile odor components of PLE-added kimchi. The pH of kimchi with higher amounts of added PLE increased slightly with two or three days ripening. The acidity of unripened kimchi or kimchi ripened for one day significantly increased with addition of PLE, while that of kimchi ripened for two or three days decreased significantly (p<0.05). Addition of PLE had no significant effect on the lactic acid bacteria count of kimchi compared to that of sugar. Overall acceptability and taste of 0.005 or 0.01% PLE-added kimchi ripened for two to three days were higher than those of other samples, whereas addition of more than 0.01% PLE to kimchi unripened or ripened for one day resulted in lower overall acceptability and taste than the reference sample. Diallyl sulfide and methyl trisulfide were newly produced by ripening of kimchi, and the amounts of some volatile odor components in kimchi were also changed during ripening.