• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.425-431
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• 2014

Most fields in highland areas are covered with rye or hairy vetch for conservation during a fallow. However, using cover crops needs an effort to sow, and this makes top soil more vulnerable to loss due to surface disturbances. The aims of this study were to develop an automatic seeding-regulator device using a low-price, extensive-use GPS sensors and a DC motors and to evaluate a working efficiency of it after adaptation to partial tillage machine for reducing seeding effort. The amount of runoff water and soil loss was evaluated with partial tillage and simultaneous-seeding after harvesting soybean, in 17% slope lysimeters. In results, the seeding amount with the machine speed was stable between $0.5{\sim}0.8m\;s^{-1}$ of working sections. The automatic control device of seeding-rate could be enough to solve the slip problems of power selecting supply system or five four-wheel drive device. In partial tillage and simultaneous seeding, runoff water was 11.6% ($1.8m^3ha^{-1}$) of the scatter-seeding control ($15.5m^3ha^{-1}$) and soil loss was 13.2% ($7kg\;ha^{-1}$) of the scatter-seeding control ($53kg\;ha^{-1}$). These results suggest that partial tillage and simultaneous-seeding methods are very effective in decreasing work effort and soil loss of sloped land.

• Restorative Dentistry and Endodontics
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• v.16 no.1
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• pp.200-208
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• 1991

The purpose of this study was to observe shear bond strength of composite resin to dentin following surface treatment. Freshly extracted forty-eight sound human molars were used in this study. They were stored at $4^{\circ}C$ physiologic saline solution before experiment. The teeth was then mounted with self curing acrylic resin in brass mold. The buccal surfaces of the teeth were grinding approximately 1.5mm by means of water-irrigated grinding wheel to expose the flattened fresh dentin surfaces. The specimens were divided into 6 groups according to preparation and treatment procedures on dentin surfaces; Group 1: Untreated after preparation with No.301 diamond point Group 2: Treated with primer for 60 seconds after preparation with No.301 diamond point Group 3: Untreated after preparation with No.700 fissure carbide bur Group 4: Treated with primer for 60 seconds after preparation with No.700 fissure carbide bur Group 5: Untreated after grinding with 600 grit silicon carbide paper Group 6: Treated with primer for 60 seconds after grinding with 600 grit silicon carbide paper Light cure dental adhesive was applicated to each specimen. Silux plus(3M) was inserted then into polyethylene tube of 3mm diameter and 3mm height, and polymerized to dentin surface. All of the specimens were stored in distilled water at $35.6^{\circ}C$ for 24 hours prior to testing. The shear bond strength was measured using an Instron Universal Testing Machine. The results obtained from this study were as follows: 1. The shear bond strength to dentin was the highest in group II. 2. The shear bond strength to dentin was the lowest in group III. 3. There was no significant difference in shear bond strength to dentin according to preparation instrument. 4. The primer treatment group showed significantly greater shear bond strength than untreated group.

• Magazine of the Korean Society of Agricultural Engineers
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• v.21 no.3
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• pp.83-91
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• 1979

This study was conducted in order to find out the performance of rice transplanters in accordance with the change of the trans-planting days after pudding and the water depth flooding the paddy field at the time of transplanting : and thus to select the optimum paddy field preparation procedures for an efficient utilization of rice transplanters. The performance factors of the two different types of rice transplanters were measured during the first 6 consecutive days after puddling and with 3 different levels of water depth flooding the paddy fields. The results of this study were analysed and summarized as follows : 1. Wheel sinkage decreased very rapidly from 0 to 2 days after puddling and slowly from 3 to 5 days after puddling. 2. The depth of the test cone penetration decreased rapidly during the first few days after puddling. It was 17.8cm just after puddling, and decreased to 13.4cm one day after puddling. After 2 days, the rate of decrease was dampened, and after 5 days it kept constant value of 9.2cm. 3. Two days after puddling, the hill interval was 15.8cm (98.75% of the preset value) for broadcasted seedling rice transplanter with 3cm flooding depth : This value was the closest to the pre-adjusted value of 16cm. The general performance of broadcasted-seedling type rice transplanter was better than that of strip-seedling type rice transplanter. 4. Usually the working performance of a rice transplanter is evaluated with uniformity and adjustability of the hill intervals. The hill interval was the most uniform and closest to the pre-set value of 16cm when planted two days after puddling with 3cm of water depth. When it was inavoidable to plant 4 days after puddling with stripseedling type rice transplanter, it is advisable to let the water flooded somewhat deeper. 5. The percentage of missing hills including floating and burried seedlings was the highest just after puddling and ie decreased substancially until 3 days after puddling and then it increased again. Hence, the optimal time transplanting is to be between 2 and 3 days after puddling. 6. Better postures of planted seedlings were found when planter 2 days after puddling than 3 days after puddling. Six cm of flooding water depth always gave the best results with respect to the postures of planted seedlings. Broadcasted-seedling rice transplanter, in general, showed better posture of planted seedlings than did strip-seedling type rice transplanter. 7. Judging from the above results, the optimal conditions will be 3cm of flooding depth and transplanting between 2 and 3 days after puddling.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.325-331
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• 2016

Computational fluid numerical analysis using the commercial code CFX was performed to develop a Pelton turbine for a pico hydro power generator using the circulating water of a cooling tower in a large building. The performance of the Pelton turbine was examined for different design factors, such as the bucket shape, in which the Pelton wheel was connected in an appropriate manner to the pipe section, and the number of buckets in order to find the optimal design of Pelton turbine for a pico hydro power using surplus water. A benchmark test was carried out on the manufactured small scale Pelton turbine to validate the design method of the Pelton turbine by numerical analysis. The results obtained by comparing the flow characteristics and power output measured using the ultrasonic flowmeter, the pressure transducer and the oscilloscope with the numerical results confirmed the validity of the analytical design method. The possibility of developing Pelton turbines for kW class pico hydro power generators using surplus water with an average circulation velocity of 1.2 m/s for the chosen bucket shape and number of buckets in a 30 m high building was confirmed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.11
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• pp.6015-6022
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• 2013

It has been known that there are large amount of nitric acid and valuable metals, copper in the plating waste solution of automobile wheel. As nitric acid and valuable metals are high price and toxic, they should be recovered for economics and environment. Plating waste was extracted with TBP diluted with kerosene. The concentration of nitric acid in aqueous phase was analyzed by titration method by NaOH solution (0.1~1.0N) and the amount of metals by ICP-MS and ICP-AES. The concentration of copper in plating waste were 76,850 mg/L. The concentration of nitric acid in plating waste was 1.02 M. After three step extraction was performed with 50% TBP, each organic phase was stripped three times with distilled water to obtain 48.1% of nitric acid. Purity of final nitric acid was over 99.9% by ICP analysis. After recovery of nitric acid, copper was extracted with various solvent extractors like PC 88A, D2EPHA, LIX 84 and ISE 106. Among these extractors, 92% of copper was recovered by ISE 106 after 1st extraction and 30% $H_2SO_4$ stripping. Copper ion was reduced with $N_2H_4$ to make metal powders, respectively.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.233-233
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• 2017

Algal communities are important to maintain the aquatic ecosystems function. Algae have short life cycles, they respond quickly to environmental change and their diversity and density can indicate and the quality of their habitat. The bloom forms before the rice seedings have emerged, it may present a physical barrier that prevents the seedlings from penetrating the floodwater. Wind may also move the algal bloom, pushing the young plants beneath the surface. Another harmful action develops when the water dries up and the algae form a layer at the bottom of the field. The layer envelops the seedlings, which are not yet deeply rooted, and drag them to the surface when the water is let in again. Soil utilization pattern can be the mail facter affecting soil physico-chemical properties, especially in soil phosphorus (P). Solid content of the algae culture solution increased with the increase in the nitrogen rather the phosphors concentration. Phosphoric acid was treated with conventional treatments (100-0%, before transplanting time-tillering stage), 50-50%, 0-100%, and un-treated. The herbicide was treated on the 7 DAT (day after transplanting). Green algae samples were collected 20 DAT. Total phosphoric acid was the highest at 0.06 in 50-50% treatment in 20 DAT. The amount of green algae was about twice (9.8 mg/20ml) that of un-treated. Total number of green algae was 54 species(Green algae 35 species, Euglena 9 species, Stone wheel 10 species). Among the phosphoric acid treatment methods, the number of occurrences of green algae were the highest with 39 species in 0-100%, followed by 50-50%, 28 species, conventional treatments, 22 species, non-treatment, 18 species, respectively. Rice Yield was not significantly different by phosphoric treatment time, but slightly higher than un-treated. The maximal algal biomass was observed about 2weeks or 1 month after transplanting; the subsequent decrease of the biomass was related to the consumption by grazers and to a deficient light under the rice canopy. Maximal algal growth was observed just before tillering. To estimate the suitable method of phosphorus application in puddled-soil drill seeding of rice, available phosphorus appearance of algal water bloom, and rice yield were investigated in paddy soil of rice-barley double cropping system.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.2
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• pp.29-34
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• 2012

Nowadays, the problem of ETCS terminal in becoming popular gradually is that there is no services except for ETC. Therefore, we need new system that provide many type of additional services at one-terminal. In this paper, we study the additory function of ETCS terminal to afford many type of the vehicle administration beside collection and provider of traffic information. We descrived the method of Eco-driving function beside to save fuel signing instant and mean fuel-efficiency, measurement of section fuel-efficiency on OLED and then brings out the best driving habit in people and to prevent dangerous at the wheel as diagnosing engine oil, cooling water, fan belt, the point of changing consumables, diagnoses to an overheated engine, charges on generator through ECU. The multi-services terminal consist of the vehicle diagnosis module base on OBD-II and ETCS terminal.

• Korean Institute of Interior Design Journal
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• v.14 no.6 s.53
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• pp.148-156
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• 2005

The purpose of this study was to investigate spatial characteristics and using behavior of activity room in skilled nursing facilities for the elderly and to provide basic guidelines about its space planning. The activity rooms in the most of the research facilities were arranged by usage modification of unnecessary spaces after the foundation of the facility, and were used not only for the program service but for the staff lounge. It decreased space speciality and resulted in limited area of the space and crowded furniture arrangement. The design guidelines for activity room were as follows. First, the space plan of activity room is based on the use of once to twice per week and for 30 minutes per use, and is mainly for the human knowledge and art programs that are appropriate for small group. Second, the activity room of the facility with less than 3 stories needs to be in the same floor as elderly individual room, but should be independent and easy to be controlled by the staff. On the other hand, in more than 4 stories facility, it is better to be in the different floor as the elderly living area such as administrational area close to the lounge and garden. Third, at least $5.9m^{2}$ per user for the area of the activity room is recommended including the elderly, staff, furniture, equipments and restroom. Fourth, the furniture of activity room includes the shelves, big table with enough knee space, wheel, and stopper, and stackable chairs. Toilets and water closet are needed for the emergency, and the windows to the corridor and curtain door should be avoided for soundproof and easy access of wheelchair users.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.4
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• pp.337-344
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• 2011

The humidification of reactant gases is crucial for efficiently operating PEM (polymer electrolyte membrane) fuel cell systems and for improving the durability of these systems. The recycle of the energy and water vapor of exhaust gas improves the system performance especially in the case of automotive application. The available humidification methods are steam injection, nozzle spray, humidification by enthalpy wheel, membrane humidifier, etc. However, these methods do not satisfy certain requirements such as compact design, efficient operation and control. In this study, a hybrid humidification system consisting of a membrane humidifier and exhaust-air recirculation units was developed and the humidification performance of this hybrid humidifier was analyzed. Finally, a new practical method for optimal design of PEM-fuel-cell humidification system is proposed.

• Korean Journal of Pharmacognosy
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• v.17 no.2
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• pp.113-122
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• 1986

In order to investigate the pharmacological activities of the combined preparation of crude drugs, Chunghyulgangki-Tang was studied. Chunghyulgangki-Tang has been widely used to cerebral apoploxy, hypertension and arteriosclerosis, etc. In this study, water extract of Chunghyulgangki-Tang was conducted in attempt to investigate for analgesic, sedative, antipyretic, isolated ileum and heart, blood vessels and blood pressure action in mice, frogs, rats, guinea-pigs and rabbits. The following results were obtained; Analgesic action by the acetic acid stimulating method in mice was recognized. Sedative activities by the wheel cage method and rotor rod method in mice were shown. Prolonged action against the hypnotic duration induced by thiopental-Na was significantly noted in mice. The effect of antipyretic in endotoxin febrile rats was significantly recognized. Spontaneous motility of the isolated ilem of mice was suppressed and contractions of the isolated ileum of mice and guinea-pigs induced by acetylcholine chloride, barium chloride and histamine were remarkably inhibited. Acceleration of isolated heart motility was shown in frogs. Vaso-dilating and hypotensive actions were recognized in rabbits. According to the above results, effects based on the oriental medicinal references were approximate to the actural experimental results.