• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.2
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• pp.37-46
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• 2014

Water for crop growth were supplied by irrigation in protected cultivation and these are accumulated in the soil and utilized for crop evapotranspiration. The study for analyzing soil moisture characteristics is necessary for adequate irrigation water and soil water management in protected cultivation. Soil moisture content, irrigation water quantity and meteorological data were monitored to analyze soil moisture increment and extraction characteristics in terms of soil layers and cucumber crop growth stages. In first cropping period, the total amount of irrigation water was 5.07 mm/day, soil moisture increment was 4.82 mm/day and soil moisture extraction was 5.56 mm/day. In second cropping period, the total amount of irrigation water was 4.82 mm/day, soil moisture increment was 4.65 mm/day and soil moisture extraction was 4.73 mm/day. Soil moisture extraction rate from 0 to 75 cm is 90.3 % in first cropping period and 79.1 % in second cropping period. The majority irrigation water were consumed in root zone, however, about 15 % of soil moisture were losses by infiltration in lower soil layer. Soil moisture extraction and extraction pattern of cucumber crop calculated in this study can be utilized as a basic data for irrigation water management in protected cultivation.

• Journal of the Korean Society of Tobacco Science
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• v.17 no.1
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• pp.62-67
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• 1995

Deliveries of tar, nicotine and carbon monoxide in mainstream smoke decreased with increment of exogenous potassium content of tobacco. Potassium malate was more effective than potassium nitrate, potassium carbonate, potassium citrate and potassium oxalate for the reduction of carbon monoxide, but potassium nitrate was more effective than potassium palate, potassium carbonat, potassium citrate and potassium oxalate for the reduction of carbon in the case of nicotine. Puff count and burning rate were slightly changed with added potassium salts.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.425-428
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• 1996

Treeing deterioration which is one of the main cause of breakdown in insulating materials is affected by temperature, applied voltage and frequency. In this study, GN was introduced to improve impact strength of DGEBA/MDA system and the temperature dependence of AC treeing deterioration in this system was investigated. Dielectric breakdown strength decreased with the increment of temperature. As temperature increased, the growth rate of tree Increased.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.8
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• pp.8-15
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• 1993

This paper describes a normalization of character which is contained in the character recognition process. Line and dot density is computed on input character image and then image mapping is executed into destination. Also recognition is processed using overlap-partitioning of character image and extraction of 4 directional feature primitives. The validity of proposed nonlinear normalization algorithm could be verified by increment of recognition rate.

• 전기의세계
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• v.24 no.5
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• pp.82-90
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• 1975

This study investigated the deterioration phenomena of the Polyethylene surface contaminated with organic(Saccharose) or inorganic(NaCl) matters through electrical and optical experiments. And also these experimental results relatively well coincided with which was treated by theoretical process. On the electrical experiment, relation between electric field intensity in corona discharge and time reached to the breakdown, and relation between total amount of charges discharged and increment of applied voltage were investigated. On the optical experiment, discharge time dependence of surface deterioration rate and process of surface deterioration in the X-ray diffraction pattern were investigated. It was concluded that chemical effects by the corona discharge deteriorated insulation characteristics of Polyethylene surface.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.2
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• pp.102-105
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• 1999

Mineralization of organic N is an important factor in determining the appropriate rate of organic matter application to paddy fields. A kinetic analysis was conducted for nitrogen mineralization of rice, barley, Chinese milk Ovetch (Astragalus sinicus L.; MV) and narrow leaf vetch straw in paddy soil. Nitrogen immobilization occurred rapidly and its rate increased in straw with high C/N ratio. The amount of nitrogen mineralization was rapid in the first year of rice-vetch cropping system. The rate constant (K) depended on the C/N ratio of organic matter. Mineralization of straw increased at high temperature. The amount of available N increment resulted in fast mineralization of straw, especially in rice and barley straw. Chinese milk vetch had the greatest mineralization rate at all temperatures and fertilization levels followed by narrow-leaf vetch. However, rice and barley straws with high C/N ratio immobilized the soil N at the initial incubation duration. Chinese milk vetch or narrow leaf vetch was not effectively mineralized in mixed treatments with rice or barley straw. The mineralization rate of organic matter was mostly affected by the C/N ratio of straw and temperature of incubation. Organic matter with low C/N ratio should be recommended to avoid the immobilization of soil N and the increasing mineralization rate of straw.

• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.21-26
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• 2005

We performed the numerical analysis on the characteristics of indoor air quality and local supply index with a variation of supply · exhaust airflow rate. We analyzed the local supply index and carbon dioxide concentration at the room and breathing zone with respect to the variation of the supply · exhaust airflow rate. From the numerical results, we found that local supply index was affected but carbon dioxide concentration was hardly affected by the variation of the airflow rate in the room. And we also knew that carbon dioxide concentration was raised in despite of the increment of the supply airflow rate in the breathing zone. After this study it is necessary to analyze the local exhaust index when we evaluate the state of the ventilation in the room.

• Journal of Preventive Medicine and Public Health
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• v.17 no.1
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• pp.239-243
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• 1984

The vascular reaction such as the indirect blood pressure and the pulse rate of the tail to the noise were examined in 8 naive Sprague-Dawley rats of both sexes. The sounds used in the experiment were 1KHz and 4 KHz, 95dB pure tone generated by Nagashima Audiometry. The indirect blood pressure and the pulse rate were checked at the rat tail by Polygraph at 5 minutes interval. The results were as follows: 1. The blood pressure and the pulse rate increased maximally 5 minutes after the exposure to both sounds. 2. The blood pressure and the pulse rate returned normal range within 20 minutes after the exposure of both sounds. 3. The increment of the blood pressure and the pulse rate was greater after the sound of 4KHz than after that of 1KHz, but it wasn't statistically significant.

• Journal of Chest Surgery
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• v.23 no.6
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• pp.1107-1117
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• 1990

The regulatory role of the post \ulcorner1-and \ulcorner2-adrenoceptors on cardiac function, particularly in coronary flow rate, was investigated in the isolated rat heart treated with 10-6 M propranolol. When introduced into the left atrium of the heart, phenylephrine[10-7-10-2 M] decreased coronary flow rate and increased mean coronary resistance in a dose related fashion, but did not affect heart rate. Methoxamine also elicited the increment of coronary resistance and the decrement of coronary flow rate, though the effects of methoxamine were weaker than those by phenylephrine. The effect of phenylephrine was inhibited by 1\ulcornerM prazosin and shifting the dose-response curve to the right. The effects of clonidine, a selective \ulcorner2-adrenoceptor agonist, were studied in the heart taken from reserpinized rats. Clonidine increased coronary resistance, decreased heart rate and coronary flow rate with a dose-dependent manner. These effects were abolished by 10-6 M yohimbine, a selective \ulcorner2-antagonist, and were not affected by 10-6M prazosin. Clonidine also decreased coronary flow and increased mean coronary resistance in electric paced heart. These effects were inhibited by rawoulscine, a selective ca-antagonist. These results indicate that the stimulation of both post \ulcorner1-and \ulcorner2-adrenoceptor causes coronary vasoconstiction. And it is inferred that this model of sympathomimetics-induced coronary vasospasm may provide a useful tool for investigating spasmolytic agents which are of benefit in the treatment of variant angina.

• Journal of Ocean Engineering and Technology
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• v.14 no.2
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• pp.106-111
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• 2000

Recently it was reported that the life of Al Sacrifical anode is being used in port piers has been significantly shortened compared with the original design life (e.g. average life shortened from 20 years to 13-15 year) Those factors involving these problems mentioned above were seemed to be a quality of anode material and diverse environmental factors such as pH flow rate temperature Dissolved oxygen Chemical oxygen demand and resistivity etcm In this study flow rate and contamination degree(pH) of sea water affecting to sacrificial anode life hve been investigated in terms of electrochemical characteristics of Al alloy sacrificial anode It was known that the lifetime of Al alloy anode was shortened not only by increasing of self-corrosion quantity by varying flow rate of sea water but also by increasing corrosion current density due to the potential difference increment between Al anode and steel structure cathode by varying contamination degree of sea water. Especially when anode current density is from 1mA/cm2 to 3mA/cm2 and flow rate of sea water is under 2m/s anode current efficiency is 90% above However flow rate is over 2m/s anode current efficiency fell down sharply due to erosion corrosion as well as galvanic corrosion.