• Journal of the Korean Vacuum Society
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• v.17 no.1
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• pp.34-39
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• 2008

We have investigated the characteristics of $Al_{0.55}Ga_{0.45}N$/GaN heterostructures with and without low-temperature (LT) AlN interlayer grown by metalorganic chemical vapor deposition. The structural and optical properties were systematically studied by Rutherford backscattering spectroscopy (RBS), X-ray diffraction (XRD), optical microscopy (OMS), scanning electron microscopy (SEM), and photoluminescence (PL). The Al content (x) of 55% and the structural properties of $Al_xGa_{1-x}N$/GaN heterostructures were investigated by using RBS and XRD, respectively. We carried out OMS and SEM experiments and obtained a decrease of the crack network in $Al_{0.55}Ga_{0.45}N$ layer with LT-AlN interlayer. A two-dimensional electron gas (2DEG)-related PL peak located at ${\sim}3.437eV$ was observed at 10 K for $Al_{0.55}Ga_{0.45}N$/GaN with LT-AlN interlayer. The 2DEG-related emission intensity gradually decreased with increasing temperature and disappeared at temperatures around 100 K. In addition, with increasing the excitation power above 3.0 mW, two 2DEG-related PL peaks were observed at ${\sim}3.411$ and ${\sim}3.437eV$. The observed lower-energy and higher-energy side 2DEG peaks were attributed to the transitions from the sub-band level and the Fermi energy level of 2DEG at the AlGaN/LT-AlN/GaN heterointerface, respectively.

• Korean Journal of Psychosomatic Medicine
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• v.11 no.2
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• pp.118-136
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• 2003

Objective: This study is to examine the neuropsychological and developmental characteristics of the Computerized Neurocognitive Function Test among normal children in elementary school. Methods: K-ABC, K-PIC, and Computerized Neurocognitive Function Test were performed to the 120 body of normal children(10 of each male and female) from June, 2002 to January, 2003. Those children had over the average of intelligence and passed the rule out criteria. One-way ANOVA and Bonferroni were used for statistical analysis. Results: In sampling of normal children in elementary school, the control of intelligence level and strict rule out criteria were applied. As a result, although 21.1% were excluded from of total participants, the children that passed the rule out criteria had over the average of intelligence and not differ in the intelligence level among the graders. Comparing Computerized Neurocognitive Function Test results among the graders, almost of variables had significant difference among the graders and especially between the 1st to 2nd and the 5th to 6th graders. In the attention tests, as rising the graders, the performance of tests were improved. In the short-term memory tests, the difference between forward and backward tests were same as the previous research result. The verbal auditory learning test composed of recall task and visual figure memory test composed of recognition task were same as the previous research result using the individual power or achievement test and also as rising the graders, the performance of those tests were improved. The higher cognitive function tests had the same results with other tests. Conclusion: The Computerized Neurocognitive Function Test devised for adult can be used of assessing child neuropsychological characteristics. For this objective, more strict sampling criteria, control of the intelligence and psychopathology were needed.

• Korean Journal of Environmental Agriculture
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• v.35 no.4
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• pp.286-293
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• 2016

BACKGROUND: 18% of difenoconazole+iminoctadin triacetate microemulsion (3%+15%) formulation were mixed and sprayed as closely as possible to normal practice on the ten of farms located in the Youngju of South Korea. Patches, cotton gloves, socks, masks and XAD-2 resin were used to measure the potential exposure for applicators wearing standardized whole-body outer and inner dosimeter (WBD). This study has been carried out to determine the dermal and inhalation exposure to difenoconazole during preparation of spray suspension and application with a power sprayer on a grape orchard. METHODS AND RESULTS: A personal air monitor equipped with an air pump IOM sampler and cassette and glass fiber filter were used for inhalation exposure. The field studies were carried out in a grape orchard. The temperature and relative humidity were monitored with a thermometer and a hygrometer. Wind speed was measured using a pocket weather meter. All mean field fortification recoveries were between 97.3% and 119.6% in the level of 100 LOQ (limit of quantification) while the LOQ for difenoconazole was $0.025{\mu}g/mL$ using HPLC-UVD. The arms exposure to difenoconazole for the mixer/loader (0.0794 mg) was higher than other body parts (head, hands, upper body, legs). The exposure to difenoconazole in the legs for applicator (3.78 mg) was highest in the parts of body. The dermal exposure for mixer/loader and applicator were 0.02 and 2.28 mg on a grape orchard, respectively. The inhalation exposure during application was estimated as 0.02 mg. The ratio of inhalation exposure to dermal exposure was equivalent to 0.9% of the dermal exposure. CONCLUSION: The inhalation exposure for applicator indicated $18.8{\times}10^{-3}mg$, which was level of 0.9% of the dermal exposure (2.28 mg). Operator exposure (0.004 mg/kg bw/day) to difenoconazole during treatment for grape is calculated as 2.5% of the established AOEL (0.16 mg/kg bw/day).

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.4
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• pp.227-234
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• 2019

This study was performed to investigate the effect of heat-stressed environment on rumen microbial diversity in Holstein cows. Rectal temperature and respiration rate were measured and rumen fluid was collected under normal environment (NE; Temperature humidity index (THI)=64.6) and heat-stressed environment (HE; THI=87.2) from 10 Holstein cows (60±17.7 months, 717±64.4 kg) fed on the basis of dairy feeding management in National Institute of Animal Science. The rumen bacteria diversity was analyzed by using the Illumina HiSeq^TM 4000 platform. The rectal temperature and respiratory rate were increased by 1.5℃ and 53 breaths/min in HE compared to that in NE, respectively. In this study, HE exposure induced significant changes of ruminal microbe. At phylum level, Fibrobacteres were increased in HE. At genus level, Ruminococcaceae bacterium P7 and YAD3003, Butyrivibrio sp. AE2032, Erysipelotrichaceae bacterium NK3D112, Bifidobacterium pseudolongum, Lachnospiraceae bacterium FE2018, XBB2008, and AC2029, Eubacterium celulosolvens, Clostridium hathewayi, and Butyrivibrio hungatei were decreased in HE, while Choristoneura murinana nucleopolyhedrovirus, Calothrix parasitica, Nostoc sp. KVJ20, Anabaena sp. ATCC 33047, Fibrobacter sp. UWB13 and sp. UWB5, Lachnospiraceae bacterium G41, and Xanthomonas arboricola were increased in HE. In conclusion, HE might have an effect to change the rumen microbial community in Holstein cows.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.37 no.4
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• pp.302-307
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• 2001

The underwater background noise measured in Geoje and Tongyoung diving fishing ground from May to December, 2000 and analyzed to get optimum carrier frequency and transmitter power level for underwater wireless telephone design. The results obtained are summarized as follows: 1. At the Geoje and Tongyoung diving fishing ground, the lowest ambient noise band was 25~30kHz with 57dB and 52dB re 1$\mu$Pa, respectively. 2. At the Geoje and Tongyoung diving fishing ground, the lowest noise band during fishing activity was 67dB and 62dB re 1$\mu$Pa, respectively. 3. At the Geoje diving fishing ground, the noise of water jetter which is a digging machine for subbottom shells was 102dB re 1$\mu$Pa. 4. Considering the design parameters of underwater wireless telephone, it is found that the optimum carrier frequency band is around 30kHz and the transmitter source level should be at least 131dB re 1$\mu$Pa for 500m range telephone.

• Journal of dental hygiene science
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• v.7 no.3
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• pp.161-166
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• 2007

Relationship of Dental Health Assessment to the Number of Existing Permanent Tooth in Senior Citizens visited a dental hospital or clinic from Some Regions. The purpose of this study was to examine the relationship of the dental health assessment of elderly people who were at the age of 65 and up to the number of existing permanent tooth in an effort to lay the groundwork for pinpointing problems with their oral status and developing programs geared toward improving their dental health and quality of life. The findings of the study were as follows: 1. Regarding self-perceived dental health, the largest group of the senior citizens that accounted for 57.9 percent didn't find themselves to be in good dental health. The second largest group that represented 32.5 percent thought their dental health was at an ordinary level, and the third greatest number of them that stood at 9.5 percent considered themselves to be in good dental health. Their self-perceived dental health status was statistically significantly different according to education and monthly income, and whether they had a job or not made a statistically significant difference to that as well(p < .01, p < .001). 2. In terms of taste appreciation, 58.7 percent, the largest group, didn't appreciate one or two kinds of taste, and their taste appreciation was statistically significantly different according to education and monthly income(p < .05, p < .01). 3. As for chewing ability, 20.6 percent were able to chew well. In regard to digestion, 69.0 percent had an ordinary level of digestive power. 4. Concerning the number of existing permanent tooth, 38.9 percent, the greatest percentage, had ten or less permanent teeth. By education, the possession of 21or more permanent teeth(40.0%) was most common among those who received high-school or higher education. The greatest group of the senior citizens with a job had 11 to 20 permanent teeth(41.7%), and the largest number of the elderly people whose monthly income was 500 thousand won or more were in possession of 11 to 20 permanent teeth(41.7%). The number of existing permanent tooth statistically significantly differed with their general characteristics(p < .01). 5. As to connections between dental health and the number of existing permanent tooth, 21 permanent teeth or more were owned by those who were in good dental health, who appreciated different tastes and whose chewing ability was good. So there was a statistically significant relationship between the two.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.4
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• pp.348-355
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• 2000

This paper described the relationship between the behavior of the Israeli carp, Cyprinus carpio and the environmental noise level due to the dynamite explosion work. The experiment was conducted in the cage ($L10{\times}W4{\times}D4 m$) of aquaculture located at Chungjoo Lake, Chechon, in 1997. The fish trajectory was obtained by the telemetry system in which a pulsed ultrasonic pinger ($50 kHz, {\phi}16{\times}L70 mm$) attached to the fish was tracked three dimensionally, and the underwater noise levels were measured. The results of the study were as follows: 1. The underwater noise levels in the normal blasting measured at a distance of 400 m from the source of noise increased by $40 dB (re 1 {\mu}Pa)$ compared to the levels before explosion. The dominant frequency and the increased power spectrum level of the underwater noise by the explosion work were $75 to 100 Hz and 22.9 to 35.3 dB$, respectively. 2. The underwater noise levels in the test blasting measured at a distance of 350 m from the source of noise increased by average $49.5 dB (re 1 {\mu}Pa)$compared to the levels before explosion. 3. The swimming area of the fish was reduced with the time after explosion, and after more than one hour the fish represented the similar swimming area and behavior to the status of right before explosion. 4, The swimming depth layer of the fish was most of the case at the sea surface less than 1,0 m except during explosion or right after of it. But the fish swam downward when an external stimulus like the explosion noise was given to the fish. 5. The average swimming speeds of the fish before, during and after the works were about 1.2 times, 1.9 times and 1.0 times of the body length, respectively, and the speed of the fish with explosion was faster 1.6 times than the speed without of that. Consequently, the explosion noise levels measured by this study were sufficiently high to affect the fish, and the heavy shock by the explosion works could produce a considerable unfavorable effects to the fish.

• Food Science of Animal Resources
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• v.32 no.2
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• pp.190-197
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• 2012

This study was performed to evaluate the extraction method (Yacon ethanol extracts; YEE, Yacon pressed extracts; YPE) and various levels (0.05-1.0%) of Yacon (Polymnia sonchifolia) on antioxidant and antimicrobial activities. In linoleic acid emulsion of YPE, there were higher iron chelation activity and antioxidant activity than those of YEE (p<0.05). A 1,1- diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activity and reducing power of both extracts showed a higher rate at 0.5% level. Ground pork patties, which contain 0.5% YEE and YPE, were manufactured and BHT (0.01%) was used as a reference. Physicochemical properties and microbial counts of ground pork patties, containing a different type of Yacon, were evaluated during the 14 d of storage at $4^{\circ}C$. A pH level, and lightness (Hunter L), as well as the yellowness (Hunter b) values of treatments were not different from those of the control (p>0.05), but increased during storage, at $4^{\circ}C$. Lightness values of ground pork patties, with Yacon extracts, showed the highest. TBARS value of ground pork patties that contains Yacon increased with increased storage at $4^{\circ}C$ (p<0.05), and pork patties with YPE or YEE retarded the lipid oxidation, during refrigerated storage, as compared to that of the CTL. Thus, YPE could be used as a potential possibility to inhibit the lipid oxidation of processed meats, during the refrigerated storage.

• The Korean Journal of Air & Space Law and Policy
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• v.1
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• pp.223-243
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• 1989

The practical application of modern space science and technology have resulted in many actual and potential gains of mankind. These successes have conditioned and increased the need for a viable space law regime and the challenge of space has ultimately led to the formation of an international legal regime for space. Space law is no longer a primitive law. It is a modern law. Yet, in its stages of growth, it has not reached the condition of perfection. Therefore, under the existing state of thing, we could carefully say that the space law is one of the most newest fields of jurisprudence despite the fact that no one has so far defined it perfectly. However, if space law can be a true jurisprudential entity, it must be definable. In defining the space law, first of all, the grasp of it's nature iis inevitable. Although space law encompasses many tenets and facets of other legal discriplines, its principal nature is public international law, because space law affects and effects law relating intercourse among nations. Since early 1960s when mankind was first able to flight and stay in outer space, the necessity to control and administrate the space activities of human beings has growingly increased. The leading law-formulating agency to this purpose is the United Nation's ad hoc Committee on Peaceful Uses of Outer Space("COPUOS"). COPUOS gave direction to public international space law by establishing the 1963 Declaration of Legal Principles Governing the Activities of the States in the Exploration and Use of Outer Space("1963 Declaration"). The 1963 Declaration is very foundation of the five international multilateral treaties that were established successively after the 1963 Declaration. The five treaties are as follows: 1) The Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space including Moon and other Celestial Bodies, 1967. 2) The Agreement on the Rescue of Astronauts, the Return of Astronauts, and the Return of Objects Launched into Outer Space, 1968. 3) The Convention on International Liability for Damage Caused by Space Objects, 1972. 4) The Convention on Registration of Objects Launched into Outer Space, 1974. 5) The Agreement Governing Activities of States on the Moon and Other Celestial Bodies: Moon Treaty, 1979. The other face of space law is it's commercial aspect. Space is no longer the sole domination of governments. Many private enterprise have already moved directly or indirectly into space activities in the parts such as telecommunications and space manufacturing. Since space law as the public international law has already advanced in accordance with the developments of space science and technology, there left only a few areas untouched in this field of law. Therefore the possibility of rapid growth of space law is expected in the parts of commerical space law, as it is, at this time, in a nascent state. The resources of the space environment are also commercially both valuable and important since the resources include the tangible natural resources to be found on the moon and other celestial bodies. Other space-based resources are solar energy, geostationary and geosynchronous orbital positions, radio frequencies, area possibly suited to human habitations, all areas and materials lending themselves to scientific research and inquiry. Remote sensing, space manufacturing and space transportation services are also another potential areas in which commercial. endeavors of Mankind can be carried out. In this regard, space insurance is also one of the most important devices allowing mankind to proceed with commercial space venture. Thus, knowlege of how space insurance came into existence and what it covers is necessary to understand the legal issues peculiar to space law. As a conclusion the writer emphasized the international cooperation of all nations in space activities of mankind, because space commerce, by its nature, will give rise many legal issues of international scope and concern. Important national and world-community interests would be served over time through the acceptance of new international agreements relating to remote sencing, direct television broadcasting, the use of nuclear power sources in space, the regularization of the activities of space transportation systems. standards respecting contamination and pollution, and a practical boundary between outer space and air space. If space activity regulation does not move beyond the national level, the peaceful exploration of space for all mankind will not be realized. For the efficient regulation on private and governmental space activities, the creation of an international space agency, similar to the International Civil Aviation Organization but modified to meet the needs of space technology, will be required. But prior to creation of an international organization, it will be necessary to establish, at national level, the Office of Air and Space Bureau, which will administrate liscence liscence application process, safety review and sale of launch equipment, and will carry out launch service.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.3
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• pp.311-321
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• 2008

In order to improve the insufficient protein content of Jeung-Pyun with respect to sitology, as well as its fermentation process, this study prepared Jeung-Pyun doughs containing 0, 5, 10, 15, and 20 g of milk, respectively, and examined their mechanical and functional characteristics. The internal structure of the Jeung-Pyun was observed by SEM. With regard to color, the L-value increased with increasing amounts of added milk, and the highest value (65.43) occurred in the group containing 20 g of added milk; however, there were no significant differences among groups. The group containing 20 g of added milk also presented the highest a-value, and the samples with added milk had higher b-values than the control. At 8 hours of fermentation, the 10 g- and 15 g-added milk groups had viscosities of 5726.67 and 6600 respectively; viscosity increased with increasing amounts of milk, and the added-milk groups had significantly higher values than the control group. Hardness also increased with increasing amounts of added milk. However, there were no significant differences in resilience and cohesive power among the groups. The groups containing 5 and 10 g of added milk had the lowest cohesion and break values. For appearance, the group without added milk had the whitest color. Pore size decreased and showed less uniformity as the amount of added milk increased. The unique tackju aroma of Jeung-Pyun decreased significantly as the level of added milk increased, and the 20 g addition presented the lowest value. The 10 g-added milk group had the highest level of sweetness, and sourness increased with increasing amounts of added milk. For softness, the control group was estimated as slightly softer than the added-milk groups. The stickiest sample was generally preferred when considering taste, white color, and sweetness. Among the quality characteristics, having greater stickiness, resilience, moisture, and softness was better in terms of chewing. Overall, the size of the Jeung-Pyun containing 10 g of milk was even and well-developed.