界面活性濟의 化學的 特性과 應用에 關한 硏究

柳珙植 群山大學校自然科學硏究所 1986 自然科學硏究 Vol.1 No.-

I have investigated from surfactant to be used widely in daily life. 1. I have found a lot of special interesting things in which consists of Hydrophiles solution and oil. 2. I have reaffirmed to find out two kinds of type of dissociation which is done and not. It would be necessary to be capable of searching for the development of use in ion. 3. I have found the result in which surfactant could be applied in every field of utilities. Above all, emulsification has been functioned with a big important utilities. Above all, only the best way to choose suitable surface tention must be understood its function and utilities of it.

금강 하류의 기초생산성에 관한 연구 : 最長漲潮期(夏8~9月)의 염소도, 수온.PH, 영양염류 변동에 관한 연구 Study on the changes of chloronity, PH, water temperature, nutrient salts during the month at the greatest tidal cycle

유공식 군산교육대학 1971 論文集 Vol.4 No.-

In order to study about the basic productivities on the estuary of the Kum River, first, I conducted several experiments on the tidal variation on the site encircled on Fig. 1. I measured PH, water temperature, outside temper ature, chloronity, nutrient salts. PH variation range was 7. 20-7. 95, water tempreature increased with outside one, chloronity varied from 1.0 to 13‰, NO2-N increase is proportional to part of fresh water flowed into the estuary and their range is 0.28-0.15㎍-aton/L. P04-P content increase is reversely proportional to fresh water content In general nutrient salts showed more higher value with water temperature increase. The results in detail of this experiment are shown up at Table 1, 2.

入出力 高調波 低減形 VVVF 시스템으로 制御되는 3相 誘導電動機 高效率 運轉

柳喆魯,李公熙,李星龍 全北大學校 1990 論文集 Vol.32 No.-

Recently, the variable speed control by the VVVF system for controlling induction motor has been applied in the various field. But the harmonic which is generated in rectifier and inverter device give rise to the various obstacles. And also the efficiency improvement of induction motor, which is occupied above 80% in the industrial areas, is important to economize the energy because the induction motor has fault that it is the low efficiency in the low load. Therefore, in this study 1. From the side of reducing harmonics in input-output currents a. The reduction of harmonics by the tap changing method of converter b. The reduction of harmonics by the PWM method of inverter 2. From the side of the variable and the high efficiency of induction motor drive a. The problem of lock by the novel PLL system b. The problem of design of the V/f controller 3. From problem of simplification of the system a. The problem of simplification of the system b. The problem of the main transformer capacity and turn ratio In comparison with optimum value by computer simulation about the above items, we have made this system in accordance with theory, and then proved this validity through experiments. And also we developed the high efficiency drive system of induction motor for reducing harmonics in input-output currents by applying this conclusion.

高調波 低減形 整流回路의 最適化에 관한 硏究

柳喆魯,金聖中,李公熙,李星龍 全北大學校 1989 論文集 Vol.31 No.-

The harmonics involved in input AC line currents of thyristor converter apparatus have generated such serious problems as burning of power condenser, misaction of UFR(protective relay), and trouble of the automatic voltage controller, etc., in transmission and distribution of electric power system. In this study, we have analyzed the characteristics of the converter for reducing harmonics, which originate all sorts of obstacles. And in order to maximize the effect for the reduction of harmonics, we researched into the following items. A. From the side of reducing harmonics. 1) Optimum value of turn ratio and number according to the increment of switching tap on interphase reactor. 2) Optimum value of control angle of tap changing. 3) Development of new tap changing algorithm according to control angle of main converter. B. From the side in consideration of economical efficiency 1) Determination of the uppermost limit according to increment of switching tap on interphase reactor. 2) Turn ratio and capacity of main trasformer. 3) Turn ratio and capacity of interphase reactor. In comparison with optimum value by computer simulation about the above items, we have made this converter system in accordance with theory, and then proved this validity through experiments. Therefore, we developed the converter of optimal condition which could be used practically by applying this conclusion.

靜止形 3相 無停電 電源 裝置用 電壓源 인버터의 出力 波形 改善

柳喆魯,李公熙,韓宇勇 全北大學校 1994 論文集 Vol.37 No.-

Uninterruptible power supply[UPS] systems are extensively used for electrical support of computers, communications and other critical systems. At present, most of all inverters used in UPS system are voltage source inverter[VSI]. But the output voltage of the UPS must be a sinusoidal wave, therefore a filter consisting of inductors and capacitors eliminates the harmonics involved in the output voltage of VSI. It is important for making UPS more compact to make the filter smaller. For this purpose, the multi step VSI for UPS systems is presented in this paper. The proposed system operates as like 24 and 36 step VSI by adding the tap changing auxiliary circuit which consists of an auto transformer and several switching elements to the double connected 12 step VSI. The basic theories of the proposed inverter system for analyzing the output waveforms are described. And to optimize the effectiveness of the harmonic reduction, the optimum turn ratio and tap changing control angle of auto transformer are decided by simulation and its validity is verified with experiment.

石灰石을 利用한 化學工業의 展望

柳珙植 군산대학교 1980 論文集 Vol.1 No.-

As stated above, we can realize that 'Lime stone' is one of the most important resources which are able to hare a dirrect connection with organic and inorganic chemical industry. 'Lime stone' is gengraphically distributed on a large scale and its deposits arc not only inexhaust ible but also rather superior ill its quality. Therefore this Lime stone Industry is considered to involve the possibility enough to he developed, and the industrialization of 'Lime stonc' call be one of new ways out of difficulty in chemical industry field in Korea, none-oil producing country, suffering with scarcity of resources in general. The materials of chemical industry being 'Lime stone', how to develop and bring up our chemical industry --- that relys on how to produce abundant electric power in low cost. Saying again, the basic problem is that electric power producing in low cost is the only way to bring lip our chemical industry. Therefore if it is possible to produce electric power abundantly in low cost by developing all the rivers possible and build up water power plants it is believed that we are able to bring up this 'Lime stone' industry with it and produce the same products from 'Lime stone' as we get from the petrolium chemical Industry.

새로운 다중 전류원 인버어터의 개발

유철로,김홍규,이공희,이성룡 全北大學校 1992 論文集 Vol.34 No.-

A new multiple current source inverter for reducing the harmonics in output current is presented in this study. Condenser capacity necessary for the inverter design is decided by the commutation analysis of current source inverter with induction motor as load. And the proposed system operates 24 phase inverter by adding only tap changing circuit which consists of several taps and static switching elements to the 12 phase inverter, which is the double connected 6 phase inverter with an interphase reactor. Also to optimize the effectiveness of the harmonic reduction, the optimum turn ratio and tap changing control angle of interphase reactor are decided by digital simulation and its validity is verified with experiment. And under the optimum condition, it is clarified that the harmonics components involved in the output currents of the proposed inverter are nearly equal to those of the conventional 24 pulse inverter.

入力電流의 高調波 低減을 위한 새로운 다이리스터 整流回路의 개발

柳喆魯,金聖中,李公熙,李星龍,高榮浩 全北大學校 1987 論文集 Vol.29 No.-

The harmonics involved in input AC line currents of thyristor rectifier apparatus have recently been a serious problem in the cause of burning power condenser, mis-action of UFR(protective relay), and trouble of the automatic voltage controller, etc, in the sending or distribution electric power system. As an effective counter-measure for this, the method of having switching taps on the conventional interphase reactor and its artificial utilization have been adapted, as we know. The conventional 3 tap method, however, is not achieved an effect of reducing harmonics under firing angle 15˚. In this paper, a new method of reducing harmonics involved in input AC line currents or output DC voltage of rectifier circuit is presented, which is due mainly to the equipment of the 2-3 switching taps on interphase reactor. Thereofre, main contents of this study are the following three items; 1) optimal number of taps 2) optimal turn ratio of interphase reactor 3) optimal control angle of interphase reactor.

Digital PLL을 利用한 誘導電動機 速度 制御 System의 인버어터 出力 波形 改善에 關한 硏究

柳喆魯,李公熙,李星龍 全北大學校 1985 論文集 Vol.27 No.-

The inverter design for improving current waveforms using only reactors and capacitors is described. Some effects of harmonics on induction motor is reduced when the improved inverter applied to digital PLL speed control system. This paper also presented a determinating method of dynamic response and stability of system using microprocessor-based digital filter. Excellent speed regulation was obtained by the improved control system.

Saccharin의 展望性있는 化學的 製法과 副産物의 利用에 關한 硏究

柳珙植 群山大學校 1983 論文集 Vol.6 No.-

It seems very likely that the consumption of saccharin will be increased, according to the increasing national income and the variety of processed foodstuffs, with demand of carolieless foodstuffs for the prevention of supernutrition and diseases of adult people. Therefore all the nations in the world have been concentrated on developing artificial sweetstuffs substituting sugar for. As a result of it, the manufacturing process in the past was the one which used to solve O-toluene Sulfon Amid with 30% Sodium Hydroxide; this time the method is the one which is solved with definite diluted Sodium Hydroxide. This is why we want to reduce the poionous content as possible avoiding conc Alkaline Substances. Para-toluen Sulfo Chloride produced as by-product seems likely to be used as the followings: (1) the Ester, treated and manufactured with Alkaline Alchol, can be used as Alkalifing Reagent. (2) This Chloride can be used as Chlorifying Agent of Carbon Acid in Organic Synthesis. (3) this Chloride is used for the manufacture of Dialky1 Amine. (4) this Chloride is used for the manufacture of Chiramine T, Water disinfectant and Halazone. As the above, in order to keep our good health and to save foreign currency, we should not import the whole quantity of original crude sugar, but develop this area, by-products produced in the manufacture, and poisonless Saccharin in large quantity. Thus, if we export this in large quantity, taking the exclusive property of each market in the world, it is expected that this would contribute to economic development for exporting Korea.