• Journal of Korean Society of Environmental Engineers
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• v.34 no.10
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• pp.656-663
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• 2012

After the construction of waterworks automatic meter reading with 15 mm diameter digital water mater with magnetoresistance sensor developed in this study at 96 households of apartment complexes located in Incheon-City B-Gu S-Dong, the feasibility of field application of waterworks automatic meter reading was evaluated. The field application of waterworks automatic meter reading was performed from July to December in 2011, and average reception rate was as low as 84.6% due to the instable wibro networks, the existence of communication blackout and temporary malfunction of router. After the extraction of 10 households with one to five residents out of 96 households by using stratified random sampling method and analysis of domestic water use, it was found that domestic water use was significant at August and showed a decreasing trend at September, followed by increase in domestic water use at November and decrease in domestic water use at December. This phenomenon should be attributed to weather factors (temperature, humidity, etc.), which significantly affected domestic water use. Similar trend in domestic water use in terms of weather factors was obtained in case of Liter per capita day of water use after the extraction of 30 households out of 96 households by using stratified random sampling method. After analysis of Liter per capita day for 96 households, single residents increases resulted in reduction of domestic water usage by about 14% of Liter per capita day. These results might be due to the fact that domestic water usage such as laundry, beverages, catering, cleaning, etc. should be required for even the household with one resident, whereas domestic water usage for those common utilization can be significantly saved for the household with more than one resident.

• Korean Journal of Agricultural Science
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• v.13 no.1
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• pp.103-112
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• 1986

This study was carried out to prevent the entwining of rice straw on rotary shaft and blade where rice straw was spreaded on paddy field as an organic source before rotary tilling. The rotary tillage was conducted in the paddy field having the soil moisture contents of 30%, 39%, 59% in dry basis and spreaded rice straw (450kg/10a) of 30cm, 45cm, 90cm length with the edged curve angles of rotary blade of $30^{\circ}$, $40^{\circ}$, $50^{\circ}$, $55^{\circ}$ at Yuseung area. And the test were performed on the plot which has width of 30cm and 5cm length and the quantity of entwined rice straw was analized. The test results were summarized as the followings. 1. Entwining phenomenon of rice straw was decreased as the blade edged curve angle increased. The edged curve angle of rotary blade must be determind by considering the characteristics of soil cutting resistance, tilling torque and entwining phenomenon of rice straw. But according to the entwining phenomenon of rice straw only, the edged curve angle of rotary blade should be bigger than $55^{\circ}$ for design. 2. Amount of entwining rice straw was minimized when soil moisture contents was 30 percent (d. b.). It would be better that rotary tillage is performed when soil moisture contents is lower than 30 percent in dry basis. 3. Amount of entwining rice straw was minimized when the length of rice straw was 30cm with $55^{\circ}$ edged curve angle. Therefore, it would be better to chop rice straw as 30cm. 4. Entwining phenomenon of rice straw was decreased as the forward speed decreased. To decrease the entwining rice straw, rotary tillage should be done with forward fist gear (0.35m/s).

• Journal of the Microelectronics and Packaging Society
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• v.24 no.4
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• pp.23-29
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• 2017

The packaged optical fiber Bragg grating sensors which were networked by multiplexing the Bragg grating sensors with WDM technology were investigated in application for the structural health monitoring of the marine trestle structure transporting the ship. The optical fiber Bragg grating sensor was packaged in a cylindrical shape made of aluminum tubes. Furthermore, after the packaged optical fiber sensor was inserted in polymeric tube, the epoxy was filled inside the tube so that the sensor has resistance and durability against sea water. The packaged optical fiber sensor component was investigated under 0.2 MPa of hydraulic pressure and was found to be robust. The number and location of Bragg gratings attached at the trestle were determined where the trestle was subject to high displacement obtained by the finite element simulation. Strain of the part in the trestle being subjected to the maximum load was analyzed to be ${\sim}1000{\mu}{\varepsilon}$ and thus shift in Bragg wavelength of the sensor caused by the maximum load of the trestle was found to be ~1,200 pm. According to results of the finite element analysis, the Bragg wavelength spacings of the sensors were determined to have 3~5 nm without overlapping of grating wavelengths between sensors when the trestle was under loads and thus 50 of the grating sensors with each module consisting of 5 sensors could be networked within 150 nm optical window at 1550 nm wavelength of the Bragg wavelength interrogator. Shifts in Bragg wavelength of the 5 packaged optical fiber sensors attached at the mock trestle unit were well interrogated by the grating interrogator which used the optical fiber loop mirror, and the maximum strain rate was measured to be about $235.650{\mu}{\varepsilon}$. The modelling result of the sensor packaging and networking was in good agreements with experimental result each other.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.3
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• pp.318-332
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• 2015

The maize production in South-eastern Asian countries showed a continuous increase with increasing poultry-livestock from the beginning of the 1990s to early 2010. Also the need for a new variety development of each contries was increased rapidly in the same period. Single-Cross hybrid varieties have been developed and supplied from 2001 instead of multi-cross maize varieties since 1992 in Indonesia. In Cambodia, CP group is mainly manufacturing feeds with most of the forage maize from farmers who are growing its seeds from the company. Cambodian main cultivars are varieties of multinational corporations such as DK8868 from Monsanto, NK6326, NK7328 from Syngenta and CP333 from CP group including local business company. Vietnam is the main maze importing country in South-Eastern Asia which had imported 13 times scale of amount compared to exports in average from 1990 to 2011. Vietnamese government has developed a range of varieties for improving their efficiency in production, such as the LVN-10 with political investments. Their production has been reached to 80% of the total. According to the 2012 MIFAFF (Ministry for Food, Agriculture, Forestry and Fisheries) data in Korea, domestic edible maize cultivation area was approximately 15,000ha. It showed 74,399 tons of production, 3.8% of food self-sufficiency in maize and around 0.9% of grain self-sufficiency rate. The consumption of grain is mostly rely on imports in Korea. To overcome the limit of the domestic seed market and increase maize self-sufficiency, the need to develop maze varieties for world-class is increasing at present through analyzing the market trend and prospect of the seed industry in South-eastern Asia.

• Sleep Medicine and Psychophysiology
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• v.15 no.2
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• pp.77-81
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• 2008

Introduction: REM sleep which shows characteristic muscle atonia and increased resistance of upper respiratory track is known to be vulnerable to sleep apnea. Previous studies reported that REM sleep-dependent (or related) obstructive sleep apnea syndrome (REM-dependent OSA) could be one of sleep disordered breathing. The present study aimed to investigate clinical findings and polysomnographic variables of REM-dependent OSA. Methods: Fifty-six patients diagnosed with mild to moderate obstructive sleep apnea by overnight polysomnography (5$53.7{\pm}16.7$ years, 42 males). REM-dependent OSA was defined as AHI-REM/AHI-NREM ratio>2. We compared clinical and polysomnographic findings between REM-dependent OSA and No REM-dependent OSA patients. Results: Among 56 patients, 37.5% (n=21, average age of $52.3{\pm}19.7$ years, 14 males) met the REM-dependent OSA criteria. There were no significant differences in age, sex and body mass index between two groups. After controlling for age, sex, body mass index and periodic leg movements index, REM-dependent OSA patients showed significantly lower AHI, lower number of oxygen desaturation events and higher stage 2 sleep proportion compared to No REM-dependent OSA patients (p=0.010, p=0.006, p=0.031, respectively). After controlling for age, sex, body mass index and periodic legs movements index, AHI-REM was positively correlated with the number of oxygen desaturation events in REM-dependent OSA group (p=0.002). Conclusion: Current results suggested that 37.5% of patients with mild to moderate severity of obstructive sleep apnea could be classified into REM-dependent OSA. REM-dependent OSA was more common in mild severity of OSA, equally prevalent in both sexes and accompanied with sleep architecture changes, i.e. increased proportion of stage 2. In addition, apneic events during REM sleep in REM-dependent OSA were related to oxygen desaturation.

• Journal of Korean Society of Forest Science
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• v.81 no.4
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• pp.337-345
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• 1992

In this research, a kinematic wave model was applied for the runoff analysis, Regulation of streamflow was estimated by the calibration of roughness coefficient as a parameter. The data analyzed were obtained from Ananomiya and Shirasaka experimental basins at Tokyo University Forest in Aichi. Estimation methods and characteristics of roughness coefficient as a evaluation method of hydrological function of forest are summarized as follows ; 1. Roughness coefficient($N_s$) indicates the resistance of hillslope to the flowing water of surface runoff. There exists an hypothesis that resistance of hillslope to flowing water increase with the growth forest and development of the $A_o$ layer. 2. Roughness coefficient($N_s$) was estimated by the parameter when the stream direct runoff was calculated by using the kinematic wave. 3. Secular change of '$N_s$' in ananomiya has a curve which has an upper limit and increases exponentially near the limit. The curve quickly increased from 1935 to 1945 when results of afforestation for erosion control were thought to be effective. On the other hand, slight increase of '$N_s$' in Shirasaka indicates that there was not such a big change in the surface of soil layer. 4. The increase of '$N_s$' was related with decrease of direct runoff and increase of base flow. It was recognized that the rate of direct runoff decreased with the improvement of forest physiognomy and the rate of base flow was increased. But absolute value of water runoff per one storm decreased in chronological order.

• Journal of Life Science
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• v.24 no.11
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• pp.1180-1186
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• 2014

Autophagy, the lysosomal degradation pathway, is an intracellular recycling system that is necessary for the metabolic benefits of exercise and for producing lasting beneficial effects of exercise in various diseases. However, the most recent studies have only examined the effect of a single bout of exercise or resistance exercise on autophagic responses. To determine the differential effects of acute and chronic exercise on the expression of autophagy-related genes in D. melanogaster, white-eyed mutant D. melanogaster were assigned randomly to four groups: control, acute exercise, 2 hr chronic exercise, and 3 hr chronic exercise. The flies were exercised using a mechanized platform known as the Power Tower. Our results revealed that a single bout of exercise resulted in increased mRNA levels of the Atg8a gene (~20%, p<0.05). However, Atg1 and Atg6 mRNA expression were not induced by acute exercise. Transcript levels of Atg6 (~29%, p<0.05) related to the nucleation of autophagosomes were significantly induced by 2 hr of chronic exercise. However, this chronic exercise was not enough to increase Atg1 and Atg8a mRNA expression. On the other hand, 3 hr of exercise for 7 days significantly increased Atg1, Atg6, and Atg8a gene expression-about 57%, 37%, and 71%, respectively (p<0.05). These results suggest that a single bout of exercise is not enough to induce full activation of selected autophagy-related genes in D. melanogaster. Our results demonstrated that chronic regular exercise induced autophagy-related gene expression, suggesting that chronic regular exercise training might be required to activate autophagic responses important for producing beneficial effects of exercise in various diseases.

• Journal of Chest Surgery
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• v.37 no.9
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• pp.735-741
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• 2004

Blood cardioplegia is known as an established cardioplegic solution during open heart surgery. Recently, the Histidine-Tryptophan-Ketoglutarate (HTK) solution has been introduced as a cardioplegia in Korea. This study was designed to compare the myocardial protective effect between the cold blood cardioplegia (CBC) and HTK solution. Material and Method: Forty patients who underwent valve surgery or coronary artery bypass surgery were randomly divided into CBC group (n=20) and HTK group (n=20). The perioperative hemodynamic and clinical data were analyzed. The concentration of CK-MB, Troponin 1 and Lactate from coronary sinus and radial arterial blood were compared for the evaluation of the myocardial damage. The postoperative serial CK-MB levels were measured. Result: The characteristics of preoperative patients were similar in two groups. The hemodynamic parameters and postoperative clinical data were also similar between the two groups. There were no statistical significances between the CBC and HTK group in the difference of biochemical markers: Δ CK-MB (15.3$\pm$26.0 vs 19.3$\pm$14.3), ΔTro-1 (2.4$\pm$4.9 vs 2.0$\pm$2.20), ΔLac (1.6$\pm$1.0 vs 1.9$\pm$2.5). The serial CK-MB levels were not significantly different between the two groups. Conclusion: These results suggested that the myocardial protective effect of HTK solution was similar to cold blood cardioplegia during open heart surgery.

• Archives of design research
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• v.16 no.4
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• pp.185-196
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• 2003

The demand for an environment-friendly transportation system, equipped with low energy consumption, and low-or zero-pollution has been on the increase since the beginning of the World Trade Organization era. Simultaneously, the consistent growth of high-speed tram technology, combined with market share, has sparked a fierce competition among technologically-advanced countries like France, Germany, and Japan in an effort to keep the lead in high-speed train technology via extensive Research and development(R＆D) expenses. These countries are leaders in the race to implement the next-generation transportation system, build intercontinental rail way networks and export the high-speed train as a major industry commodity. The need to develop our own(Korean) 'high-speed train' technology and its core system technology layouts including original technology serves a few objectives: They boost the national competitive edge; they develop an environmental friendly rail road system that can cope with globalization and minimize the social and economic losses created by the growing traffic-congested delivery costs, environment pollution, and public discomforts. In turn, the 'G7 Project-Development of High Speed Railway Technology' held between 1996 and 2002 for a six-year period was focused on designing a domestic train capable of traveling at a speed of 350km/h combined and led to the actual implementation of engineering and producing the '2000 high-speed train:' This paper summarizes and introduces one of the G7 Projects-specifically, the design segment achievement within the development of train system engineering technology. It is true that the design aspect of the Korean domestic railway system program as a whole was lacking when compared with the advanced railroad countries whose early phase of train design emphasized the design aspect. However, having allowed the active participation of expert designers in the early phase of train design in the current project has led to a new era of domestic train development and the implementation of a way to meet demand flexibly with newly designed trains. The idea of a high-speed train in Korea and its design concept is well-conceived: a faster, more pleasant, and silent based Korean high-speed train that facilitates a new travel culture. A Korean-type of high-speed train is acknowledged by passengers who travel in such trains. The Korean high-speed prototype train has been born, combining aerodynamic air-cushioned design, which is the embodiment of Korean original design of forehead of power car minimized aerodynamic resistance using a curved car body profile, and the improvement of the interior design with ergonomics and the accommodation of the vestibule area through the study of passenger behavior and social culture that is based on the general passenger car.

• Korean Journal of Environmental Agriculture
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• v.16 no.1
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• pp.7-13
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• 1997

Tomatoes are flooded differently 0, 5, 10 and 15 ㎝, according to the developing stages such as transplanting stage under the condition of green house. Along with this, they are treated according to the time condition such as 6, 12, 24, 48 and 120 hours. The results obtained are summarized as follows. As the depth of flooding got deeper and the hours got longer, plant height, number of leaves, shoot and root decreased significantly. Flowering was possible for 24 hours in the flooding of 0 ㎝, for 6 hours in $5{\sim}10$ ㎝, but not possible after 6 hours in 15 ㎝. Without regard to the depth of flooding, adventitious root came into being before or after 48 hours of the treatment. Root activity diminished gradually as hours of treatment went by, but diminished rapidly over the depth of 5 ㎝. Chlorophyll content decreased similarly as in the case of root activity. Diffusion resistance of stomata cell increased as hours of treatment passed and depth increased. Photosynthesis and respiration diminished according as the hours and depth of treatment increased. Respiration diminished a little gradually but photosynthesis weakened greatly as the depth of treatment became greater and after 48 hours of treatment. Diseases occurred remarkably in proportion to the depth of treatment and the increase of hours. The possibility of preventing by means of insecticide treatment showed the same tendency as in the seedling stage. But its effect was not significant. After 120 hours yields could not be expected because tomatoes died without regard to the depth of flooding. Instead of the depth, numbers of fruits per plant decrease of individuals or variation of average weight of a fruit was recognized. Especially average weight increased in accordance with the increase of the depth. There was positive correlation between all the characters, such as plant height, number of leaves, fresh weight, chlorophyll content, root activity and yield traits, but negative correlation between these and epinastic curvature, diffusion resistance and adventitious root.