• Journal of the Korean Vacuum Society
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• v.15 no.6
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• pp.547-555
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• 2006

The Pohang Light Source (PLS) of Pohang Accelerator Laboratory (PAL), which was constructed in 1994, is a 3rd generation synchrotron light source user facility. It consists of 2.5 GeV linear accelerator and a storage ring with circumference of 280 m. Presently, 27 beamlines around the storage ring are in operation providing synchrotron radiations to users. In addition, PAL has a construction project of the 4th generation light source. In this paper, the operation status of the PLS is described and the prospect of the 4th generation light source is reviewed.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.4
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• pp.534-541
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• 2012

This paper tries to elicit an optimal generation mix of Korea. Two approaches, using the screening curve method and taking advantage of a generation expansion planning tool, WASP-IV, are applied in getting the mix. The data used in this study is based on the 5th basic plan for long-term electricity supply and demand. The Load Duration Curve, that is needed for applying Screening Curve Method(SCM), is made based on the load profile in 2010. In our using SCM, the nuclear plant's operation characteristic, carbon emission cost and spinning reserve are considered. In using WASP-IV to get the adequate generation mix, the base and target demand forecasts in the 5th basic plan are used and the carbon emission cost is also considered. In this paper, It introduces the domestic adequacy generation mix in 2024 though SCM and WASP-IV.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.249-249
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• 2000

This paper introduces a clean mobile robot fur 4th generation LCD cassette, which is guided by optical sensor and position compensation using vision module. The mobile robot for LCD cassette transfer might be controlled by AGV controller which has powerful algorithms. It offers optimum routes to the destination of clean mobile robot by using dynamic dispatch algorithm and MAP data. This clean mobile robot is equipped with 4 axes fork type manipulator providing repeatability accuracy of $\pm$ 0.05mm.

• Journal of Sericultural and Entomological Science
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• v.23 no.1
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• pp.32-37
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• 1981

It is necessary to improve new silkworm variety suitable for the artificial diet different from the mulberry leaves in physical and chemical natures. The silkworms fed on artificial diet show low productivity in general. So the effectiveness of selection for cocoon characters was studied when the silkworms were reared on the artificial diet for several generations. The results obtained are as fellows: 1. There is no correlation between the cocoon shell weight and the cocoon shell percentage in female cocoons of both Sa and Y strains but in male cocoons. 2. No correlation exists between the weight of a cocoon and a cocoon shell percentage of male cocoons in Sa strain. 3. There is a specific effect of the artificial diet on selection between Japanese and Chinese strains compared with the mulberry leave rearing. 4. The cocoon quality of first generation in artificial diet rearing was very inferier to that of previous generation in mulberry leave rearing in both Sa and Y strains, but the effect of selection rapidly increased in first and second generation.5. Very high mortality was noted in 4th generation to the degree of hardness for successive generation. 6. From 6th generation to 10th generation, the effectiveness of selection for cocoon characters increased continuously except the cocoon shell percteage.

• Nuclear Engineering and Technology
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• v.51 no.2
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• pp.546-555
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• 2019

Since the first nuclear reactor first critical, nuclear systems has gone through four generations of history, and the fourth generation nuclear system will be truly realized in the near future. The notions of SVBR and lead-bismuth eutectic alloy coolant put forward by Russia were well received by the international nuclear science community. Lead-bismuth eutectic alloy with the ability of the better neutron economy, the low melting point, the high boiling point, the chemical inertness to water and air and other features, which was considered the most promising coolant for the 4th generation nuclear reactors. This study mainly focuses on the structural design optimization of the 4th-generation reactor coolant pump, including analysis of external characteristics, inner flow, and transient characteristic. It was found that: the reactor coolant pump with a central symmetrical dual-outlet volute structure has better radial-direction balance, the pump without guide vane has better hydraulic performance, and the pump with guide vanes has worse torsional vibration and pressure pulsation. This study serves as experience accumulation and technical support for the development of the 4th generation nuclear energy system.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.7
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• pp.52-58
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• 2012

In this study, we have investigated the effect of the solar power generation facilities on the power quality of interconnected solar power generation system. When the solar power generation facility was connected to the distribution system, whether the solar power generation is under operation or not, Peak factor of current was increased to 0.033[%], Frequency is deviated from $60{\pm}0.2$[Hz] and also Short term flicker indication($P_{st}$) increased to 0.213[p.u.] compare with the disconnected situation. Harmonic current [%] in orders was 11.42[%] maximum under 11th orders and was 7.861[%] between 11th and 17th orders. These values were about 3 or 4 times compared with "the power system interconnection technique standards" at the same situation above. Therefore, we could confirmed that the solar power generation facility, when it was connected to the existing distribution system, made bad influence on the power qualities such as the peak factor of current, frequency regulation, short term flicker indication($P_{st}$) and harmonic current [%] in orders etc.

• The Korean Journal of Ecology
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• v.22 no.5
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• pp.287-294
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• 1999

During the period from April to October, 1998 the authors investigated the gall development process of Chinese gallnuts (Schelchtendalia chinensis) on sumac (Rhus javanica) at Mt. Goduk near Chonju city in Chonbuk province. The majority (56.8%) of chinese gallnuts were formed on first pinnates and 24.3% on second pinnates of sumac leaves. Galls began to form from the 1st of June and grew slowly until the 24th of June. Galls enlarged rapidly after the 1st of August, but their growth rates decreased after the 26th of August and stopped growing after the 8th of September. Alate viviparous females escaped from galls after the 24th of September. Fundatricies, the second generation in the galls, exuviated three times to become adults on the 24th of June. Fundatrix adults bore 1∼10 eggs in the body and laid 1∼16 nymphs of the second generation. Nymphs of the second generation began to appear on the 17th of June and had matured completely on the 14th∼24th of July. Adults of the second generation bore eggs in the body. Thus the developmental period of the second generation was 27∼37 days. Nymphs of the third generation appeared on the 14th of July and finally alate viviparous females were developed on the 24th of September. During the two months from the beginning of the third generation to the appearence of the final alate viviparous females, there should be at least two generations, that is, the third and fourth generations. The fourth generation seems to begin at about the 20th August because the number of inhabitants (2,859 individuals) in galls on the 26 th of August had increased more than 10 times those (263 individuals) on the 19 th of August. The tannin content of galls was 65.04∼68.23% while that of sumac leaves and stems was 11.56%, 3.49% respectively.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.3
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• pp.38-49
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• 1998

The 3rd generation optical pick-up used popularly in resent years is composed of many optical and electronic components such as laser diode, photo diode, beam splitter, objective lens, grating lens, concave lens, collimator lens etc. Therefore, the design of its optical system and its main base which the said optical and electronic components are set on, is complicated and needs high precision. Its assembly and adjustment in the production line is also difficult. This complication and the demand of high precision get its production cost to be high and its reliability to be low. In this paper, the 4th generation optical pick-up is designed and developed, with the hologram device which laser diode. photo diode, beam splitter. and grating lens are integrated in. This optical pick-up reduces the number of points of adjustment by 3, compared with the 3rd generation optical pick-up of which the number of points of adjustment is 6. This optical pickup also decreases by 4 the number of points of W bonding to have bad influence on environmental reliability, decreases by about 10 the number of parts, and establishes about 20% cost-down of material cost, compared with the 3rd generation optical pick-up.

• Korean Journal of Agricultural Science
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• v.42 no.4
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• pp.305-311
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• 2015

In this research, we surveyed the yield change of garlic cultivation with seed bulbs according to annual field culture after induced meristem culture. From 2007 to 2013, yearly produced seed bulbs from $2^{nd}$ to $8^{th}$ generation were cultivated in the Muan field. Over the generations, the general growth characteristics such as the plant height, leaf number, leaf length and stem diameter were all decreased. When we compared the conventional seed bulbs and TCR ones, the plant height and stem diameter showed bigger difference. And the TCR seed bulbs showed a week late harvest time against the conventional ones. The yield of $2^{nd}$ generation was 72.3 g and 57.1 g for the $8^{th}$ generation. However every generation showed higher yield than conventional seed garlic's ones as 43.9 g. The yield index showed the same trend as $2^{nd}-8^{th}$ to 63% to 21%. After the tissue culture of garlics, the viral infections (OYDV and GSV) of TCR was far less than that of conventional ones. In case of LYSV, the infection ratio was 6.7% at $2^{nd}$ generation and 26% at $8^{th}$. However, the ratio was far less than that (80%) of the conventional ones.

• Proceedings of the Technology Innovation Conference
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• 2003.06a
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• pp.26-40
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• 2003

Korean enterprises have increased their R&D efforts to a large scale since the 1990s, especially after IMF jurisdiction period. The number of research institutes and R&D resources increased sharply. In line with the increase of R&D efforts, this paper investigates how well Korean firms manage R&D capabilities. According to our analysis, Korean enterprises adopt about the 2.3th to 2.7th generation of R&D management. In spite of insufficient R&D resources, Korean SMEs adopt a similar level of R&D management practice to that of big firms. However, some big enterprises have already adopted the 4th generation of R&D management. Also, many SMEs adopt a much lower level of R&D management than average level. In this sense, it is necessary to make an in-depth study on firms'R&D management capabilities by utilizing various factors of R&D generation model.