• Analytical Science and Technology
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• v.25 no.6
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• pp.339-344
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• 2012

In this research, hydride generation in HPLC-ICPMS for the selenium speciation was investigated. Chemical and photochemical vapor generation techniques were compared for the effective generation of selenium vapour. $HBr/KBrO_3$ was used for the chemical reduction and a UV lamp was used for the photochemical reduction. It was found out that the photochemical reduction was more effective than the chemical reduction in all of selenium species studied. The optimum conditions for the generation of vapour are 0.4% KI, 2.5% $NaBH_4$, and 1.0 M HCl. The enhancement factor using a photochemical hydride generation was from 6.3 to 16.7 times for inorganic and organic selenium species.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.4 no.2
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• pp.193-198
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• 2004

This paper describes an automatic finite element (FE) mesh generation for three-dimensional structures consisting of tree-form surfaces. This mesh generation process consists of three subprocesses: (a) definition of geometric model, (b) generation of nodes, and (c) generation of elements. One of commercial solid modelers is employed for three-dimensional solid structures. Node is generated if its distance from existing node points is similar to the node spacing function at the point. The node spacing function is well controlled by the fuzzy knowledge processing. The Voronoi diagram method is introduced as a basic tool for element generation. Automatic generation of FE meshes for three-dimensional solid structures holds great benefits for analyses. Practical performances of the present system are demonstrated through several mesh generations for three-dimensional complex geometry.

• Wind and Structures
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• v.32 no.4
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• pp.321-340
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• 2021

In 2019, 5.6% of the total energy produced worldwide came from wind. Offshore wind generation is still a small portion of the total wind generation, yet its growth is exponential. Higher availability of sites, larger producibility and potentially lower environmental impacts make offshore wind generation attractive. On the other hand, as the water depth increases, fixed foundations are no more viable, and the new frontier is that of floating foundations. This paper brings an overview of why and how offshore wind energy should move deep water; it contains material from the Keynote Lecture given by the first author at the ACEM20/Structures20 Conference, held in Seoul in August 2020. The paper is organized into four sections: the first giving general concepts about wind generation especially offshore, the second and the third considering economic and technical aspects, respectively, of offshore deep-water wind generation, in the fourth, some challenges of floating offshore wind generation are presented and some conclusions are drawn.

• The Journal of Society for e-Business Studies
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• v.17 no.2
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• pp.63-72
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• 2012

The Korean telecommunications market has been expanding swiftly, these days, to be saturated. In this environment, the upcoming mobile telecommunication market, where 4G service was introduced this year, is becoming more substitutive and competitive. Thus, the demand forecasting of 4G service is very difficult, while it is critical to market success. This paper adopts a multi-generation diffusion model to capture the diffusion and substitution patterns for two successive generation of technological services, i.e., 3G and 4G mobile telecommunications services. The three parameters, i.e., the coefficient of innovation, the coefficient of imitation, and the coefficient of market potential, used in the multi-generation diffusion model based on Norton and Bass[11] are obtained by inference from similar substitutive relations between older and newer telecommunication services to 3G and 4G services. The simulation results show that the Bass type multi-generation model can be successfully applied to the demand forecasting of newly introduced 4G mobile telecommunication service.

• Korean journal of applied entomology
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• v.16 no.1 s.30
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• pp.13-19
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• 1977

The smaller brown planthopper overwinters mostly as the fourth instar nymph. The emerged adult disperses to winter barley or wheat plants. The adult of the first generation disperses into the rice field, and spends three generations in the rice field. The population densities of the adults of the first generation and the overall density of the second generations are the most important in relation to the incidents of the rice stripe disease which is transmitted by this insects. This study was intended to analyse the population increases in these important generations in relation to the kind and the different growing stage of the host plants. The insects were reared on potted host plants of different growing stage in the insect cages. The population increases of the insects in the cages were compared with those on the rice seedlings in the laboratory. The results are as follows: 1. The average longevities of the adults of the generations were 13.4 days for the overwintered, 12.9 days for the first, and 10.2 days for the second generation, and showed no significant differences between the generations even they seemed to be shorter than normal condition probably caused by the frequent disturbance at the time of food renewal in 2 or 3 days. 2. When they were reared on the rice seedling, the average numbers of the eggs per female were 131.2 for the overwintered generation, 124.9 for the first generation grown on the barley, and 142.3 for the second generation grown on rice, and shelved no significant differences between the generations. More than $90\%$ of the eggs were laid within 3 weeks. 3. The hatchabilities of the eggs laid on the rice seedling in laboratory were $77.4\%$ for the first generation, $93.1\%$ for the second generation and $62.1\%$ for the third generation. The estimated hatchabilities of the eggs were $67.5\%$ for the first generation, $84.1\%$for the second generation, and $21.9\%$ for the third generation with the growing plants on the plots. The hatchability on the eggs laid by the adults infested on the barley on May 17 was $13.5\%$ compared with $67.5\%$ for the eggs laid by those infested on barley in late April. 4. The average total nymphal periods were 19.4 days for the first generation, and 13.3 days for the second generation in the laboratory and the mortalities of the nymphs seemed to related with the growing stages of the host plants. 5. With the pot experiments, the average per cents of the emerged adults were $37.2\%$ for the first generation, $55.3\%$ for the second generation, and $11.6\%$, for the third generation. The average numbers of the emerged adults were $7.4\%$ for the pots infested on the barley on May 17, instead of $37.2\%$ adults for those infested in late April. 6. From above results, it may suggest that the innate qualities of the insect are not significantly different between generations, and the differences in the increase of the population for the generations might effected considerably by the differences in the physiological conditions of tile host plant, besides the differences in physical and other biological factors.

• Journal of Korea Society of Digital Industry and Information Management
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• v.18 no.4
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• pp.111-122
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• 2022

Many companies are now studying these generational conflict issues and seeking countermeasures. As seen in the recent performance-based pay issue, the MZ generation is boldly showing their intention unlike the previous generation. This study focuses on LX Hausys' education program to overcome the generation gap. As a representative field education program of LXHausys, it is a longevity education program that was developed and operated at the end of 14 years and has been in operation so far. By acknowledging and understanding the generation gap through this educational program, it was possible to see that they could sympathize and accept each other one step further, and that trust in each other was formed on the basis of it. The success factors of the generation empathy program were identified as the willingness to share perceptions between labor and management, participatory education programs, active participation of members, and overcoming generation empathy. Through such education, the organization should continuously raise the issue of generational empathy and allow members to recognize it as an object to overcome. To this end, efforts should be made to overcome generational differences.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.207-211
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• 2000

The mobile communication technology which provides various data service and satifies the required quality in wireless environment can be classified as the forth generation mobile communication technology the forth generation communication technology must has diference with the 2nd and 3nd generation mobile communication technology. It must has the more advanced and more united shape than 3nd generation mobile communication. The forth generation mobile communication technology include following technology: Adaptive coding ar modulation, Smart antenna, Interference cancellation, Advanced handoff mechanism between networks. In this study, I represent the development and standardization of this technology.

• Vacuum Magazine
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• v.4 no.4
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• pp.14-17
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• 2017

Recently, quantum-dots light emitting diodes (QLEDs) are considered as a next-generation display due to the superior luminescence behaviors, photo stability and narrow spectral emission bandwidth. Moreover, the emission color of QLEDs can be easily controlled by changing the dimension of quantum dots (QDs). A flexible display based on QLEDs can be achieved using low-cost solution process, such as a printing technology. Therefore, QLEDs are expected as a next generation display. In this document, recent progresses in QDs technology will be introduced.

• Tribology and Lubricants
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• v.13 no.4
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• pp.26-32
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• 1997

The heat generation of the angular contact and the deep groove ball bearing is studied experimentally and numerically. The temperature variation of the inner and outer races and the temperature increase distribution are measured for the shaft rotational speeds, preloads, viscosities of the lubricant and lubrication methods. The measured temperature distributions are used as the input data of the numerical simulation to estimate the heat generation rate at the bearing. The temperatures of the inner and outer race increase more rapidly and approach faster to their steady values as the rotational speed increases. The optimal viscosity of the oil to minimize the heat generation is 8~10 cSt at 4$0^{\circ}C$ when the oil-air lubrication method is adopted. The heat generation of the bearing increases with the rotational speed and depends more on the lubrication method than on the preload variation.

• The Journal of Korea Robotics Society
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• v.4 no.1
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• pp.56-61
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• 2009

A probability-based data generation is a typical context-generation method that is a not only simple and strong data generation method but also easy to update generation conditions. However, the probability-based context-generation method has been found its natural-born ambiguousness and confliction problems in generated context data. In order to compensate for the disadvantages of the probabilistic random data generation method, a situation propagation network is proposed in this paper. The situation propagating network is designed to update parameters of probability functions are included in probability-based data generation model. The proposed probability-based context-generation model generates two kinds of contexts: one is related to independent contexts, and the other is related to conditional contexts. The results of the proposed model are compared with the results of the probabilitybased model with respect to performance, reduction of ambiguity, and confliction.