• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.981-983
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• 2000

Linear induction motors have static and dynamic end effects due to its finite core length, so that per-phase impedances are asymmetric and the air gap flux distribution is distorted. Because of these points the d-q equivalent circuit model considering both end effects has not been exactly completed. So this paper proposes a characteristic analysis method considering both static and dynamic end effect of the LIM. This method is to utilize asymmetric d-q equivalent circuit model with dynamic end effect coefficient. As a result, it is shown that the simulation results have a good agreement with experimental ones.

• Korean Journal of Mathematics
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• v.29 no.2
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• pp.371-386
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• 2021

This paper investigates two discrete time queueing inventory models with positive service time and lead time. Customers arrive according to a Bernoulli process and service time and lead time follow geometric distributions. The first model under discussion based on replenishment of order upto S policy where as the second model is based on order placement by a fixed quantity Q, where Q = S - s, whenever the inventory level falls to s. We analyse this queueing systems using the matrix geometric method and derive an explicit expression for the stability condition. We obtain the steady-state behaviour of these systems and several system performance measures. The influence of various parameters on the systems performance measures and comparison on the cost analysis are also discussed through numerical example.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.33 no.1
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• pp.9-26
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• 1997

Stokes drift(SD) and Lagrangian discharge(LD) are important factors for analysis of flushing time, tidal exchange, solute transport and pollutant dispersion. The factors should be calculated using the approached method to flow phenomena. The aim of this paper re-examines the previous procedures for computing the SD and LD, and is to propose the new method approached to stratified flow field in the cross-section of coastal region, e.g. Masan Bay. The intensity of velocity near the bottom boundary layer(BBL) depends on the sea-bed irregularity in the coastal estuaries. So we calculated the depth mean velocity(DMV) considering that of BBL omitted in Kjerfve's calculation method. It revealed that BBL effect resulting in application of the bay acts largely on DMV in half more among 1l stations. The new expression of SD and LD per unit width in the cross-section using the developed DMV and proposed decomposition procedure of current were derived as follow : $$Q=u_0+\frac{1}{2}H_1{U_1cos(\varphi_h-\varphi_u)+U_3cos(\varphi_h-\varphi{ud})} LD ED SD$(Q_{skim}+Q_{sk2}) The third term, $Q_{sk2}$, on the right-hand of the equation is showed newly and arise from vertical oscillatory shear. According to the results applied in 3 cross-sections including 11 stations of the bay, the volume difference between proposed and previous SD was founded to be almost 2 times more at some stations. But their mean transport volumes over all stations are 18% less than the previous SD. Among two terms of SD, the flux of second term, $Q_{skim}$, is larger than third term, $Q_{sk2}$, in the main channel of cross-section, so that $Q_{skim}$ has a strong dependence on the tidal pumping, whereas third term is larger than second in the marginal channel. It means that $Q_{sk2}$ has trapping or shear effect more than tidal pumping phenomena. Maximum range of the fluctuation in LD is 40% as compared with the previous equations, but mean range of it is showed 11% at all stations, namely, small change. It mean that two components of SD interact as compensating flow. Therefore, the computation of SD and LD depend on decomposition procedure of velocity component in obtaining the volume transport of temporal and spacial flow through channels. The calculation of SD and LD proposed here can separate the shear effect from the previous SD component, so can be applied to non-uniform flow condition of cross-section, namely, baroclinic flow field.

• Journal of Ginseng Research
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• v.36 no.3
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• pp.277-290
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• 2012

The metabolic profiles of Panax quinquefolius and its associated therapeutic values are critically affected by the repetitious steaming times. The times-dependent steaming effect of P. quinquefolius is not well-characterized and there is also no official guideline on its times of steaming. In this paper, a UPLC-Q-TOF-MS/MS method was developed for the qualitative profiling of multi-parametric metabolic changes of raw P. quinquefolius during the repetitious steaming process. Our method was successful in discriminating the differentially multi-steamed herbs. Meantime, the repetitious steaming-inducing chemical transformations in the preparation of black American ginseng (American ginseng that was subjected to 9 cycles of steaming treatment) were evaluated by this UPLC-Q-TOF-MS/MS based chemical profiling method. Under the optimized UPLC-Q-TOF-MS/MS conditions, 29 major ginsenosides were unambiguously identified and/or tentatively assigned in both raw and multi-steamed P. quinquefolius within 19 min, among them 18 ginsenosides were detected to be newly generated during the preparatory process of black American ginseng. The mechanisms involved were further deduced to be hydrolysis, dehydration, decarboxylation and addition reactions of the original ginsenosides in raw P. quinquefolius through analyzing mimic 9 cycles of steaming extracts of 14 pure reference ginsenosides. Our novel steaming times-dependent metabolic profiling approach represents the paradigm shift in the global quality control of multi-steamed P. quinquefolius products.

• Analytical Science and Technology
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• v.30 no.6
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• pp.379-389
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• 2017

In this study, we set up an analytical method that can be used for rapid and accurate determination of representative isoquinoline alkaloids in medicinal plants using UPLC-ESI-Q-TOF MS (ultra pressure liquid chromatography-electrospray ionization-quadrupole-time-of-flight mass spectrometry). The compounds were eluted on a C18 column with 0.1 % formic acid and acetonitrile, and separated with good resolution within 13 min. Each of the separated components was characterized by precursor ions (generated by ESI-Q-TOF) and fragment ions (produced by collision-induced dissociation, CID), which were used as a reliable database. We also performed method validation: analytes showed excellent linearity ($R^2$, 0.9971-0.9996), LOD (5-25 ng/mL), LOQ (17-82 ng/mL), accuracy (91.6-97.4 %) as well as intra- and inter-day precisions (RSD, 1.8-3.2 %). In the analysis of Chelidonium majus L., magnoflorine, coptisine, sanguinarine, berberine and palmatine were detected by matching retention times and characteristic fragment ion patterns of reference standards. We also confirmed that, among the quantified components, coptisine was present in the highest quantity. Furthermore, alkaloid profiling was carried out by analyzing the fragment ion patterns corresponding to peaks of unknown components. In this manner, protopine, chelidonine, stylopine, dihydroberberine, canadine, and nitidine were tentatively identified. We also proposed the molecular structure of the fragment ions that appear in the mass spectrum. Therefore, we concluded that our suggested method for the determination of major isoquinoline alkaloids by UPLC-Q-TOF can be useful not only for quality control, but also for rapid and accurate investigation of phytochemical constituents of medicinal plants.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.10
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• pp.585-596
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• 2004

In this paper, finite element analysis for a PMASynRM is presented and the characteristic analysis of inductance and torque is performed under the effect of saturation. The focus of this paper is characteristic analysis of d and q-axis inductances and torque according to magnetizing quantity of interior permanent magnet for PMASynRM. The d and q-axis current component ratios, load angles of a PMASynRM are investigated quantitatively on the basis of the proposed analysis method and the experimental test. Comparisons are given with output characteristic curves of normal SynRM and those according to the load in PMASynRM, respectively And it is confirmed that the proposed model results in high output power performance.

• Proceedings of the KIEE Conference
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• summer
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• pp.914-916
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• 2004

In this paper, finite element analysis for a PMASynRM is presented and the characteristic analysis of inductance and torque is performed under the effect of saturation. The focus of this paper is characteristic analysis of d and q-axis inductances and torque according to magnetizing quantity of interior permanent magnet for PMASynRM. The d and q-axis current component ratios, load angles of a PMASynRM are investigated quantitatively on the basis of the proposed analysis method and the experimental test. Comparisons are given with output characteristic curves of normal SynRM and those according to the load in PMASynRM, respectively. And it is confirmed that the proposed model results in high output power performance.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.8
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• pp.471-476
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• 2013

The present study has been carried out to elucidate the optimal method for the performance test of a refrigerator vacuum insulation panel (VIP), by using numerical heat transfer analysis. Three locations of heat flux meter have been tested, for deriving the best test method to clarify the normal or the abnormal condition of the vacuum insulation panel in a refrigerator. The first location of the heat flux sensor is at the same place as the heater, the second one is at the nearby side location of the heater and the third one is at the opposite side location of heater in the refrigerator. The heat flux and $1/q^{{\prime}{\prime}^2}$ or $q^{{\prime}{\prime}^4}$ were calculated for the cases with the normal VIP, and with the abnormal VIP, and their differences analyzed. From the present study, the first and the second method had a mere difference characteristics of heat flux and $1/q^{{\prime}{\prime}^2}$ or $q^{{\prime}{\prime}^4}$, between the cases with the normal or the abnormal VIP. The magnitude of the heat flux after 300sec had a great difference between the cases with the normal or abnormal VIP for the third method, and it could be considered the most optimal method to test the performance of a refrigerator vacuum insulation panel.

• Korean Journal of Environment and Ecology
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• v.32 no.5
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• pp.513-531
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• 2018

This study compared forest vegetation in Chungcheongnam-do Provincial Park (Deogsan, Chilgabsan, and Daedunsan) from 2006 to 2016. The results of the analysis on the vegetation of the research sites by the phytosociological method showed that the Deogsan Provincial Park had Quercus mongolica community, Pinus densiflora community, Q. variabilis community, and Zelkova serrata community. Chilgabsan Provincial Park had Q. variabilis community, Q. mongolica community, P. densiflora community, and Carpinus laxiflora community. Daedunsan Provincial Park had Q. mongolica community, Q. variabilis community, Q. serrata community, C. tschonoskii community, C. laxiflora community, P. densiflora community, and Q. acutissima community. The importance value in each Provincial Parks was analyzed as follows. The importance value of Q. mongolica(72.35) was the highest in Deogsan Provincial Park, and followed by P. densiflora(70.25), Q. variabilis(53.11), Styrax japonicus(11.44), Prunus sargentii(11.17), and Fraxinus rhynchophylla(10.41). Q. variabilis(73.34) was the highest in Chilgabsan Provincial Park and followed by, P. densiflora(58.71), Q. mongolica(57.02), C. laxiflora(18.84), Q. serrata(13.48), and Prunus sargentii(13.31). The importance value of Q. mongolica(57.03) was the highest in Daedunsan Provincial Park and followed by Q. variabilis(31.98), Q. serrata(31.53), P. densiflora(16.80), C. tschonoskii(16.50), C. laxiflora(16.07), S. obassia(15.76), and Acer pseudosieboldianum(10.09). The results of DBH analysis of the major species having the high importance value showed the normal density distirbution of Q. mongolica, and Q. variabilis in Deogsan Provincial Park, so the dominance status of these species is likely to continue. Q. variabilis, Q. mongolica, and P. densiflora in Chilgabsan Provincial Park showed the normal density distribution showed the density of normal distribution, so the dominance status of these species is likely to continue. However, the dominance status of C. laxiflora, and Q. serrata is likely to be expanded in the future due to the high density of young individuals. Q. mongolica, and Q. variabilis in Daedunsan Provincial Park showed the density of reverse J-shaped curve, so the dominance status of these species is likely to continue, and C. tschonoskii, and P. densiflora had a formality distribution, suggesting continuous domination of these species over the other species for the time being. Additionally the dominance status of C. laxiflora, and Q. serrata is considered to be expanded in the future due to the high density level of young individuals.

• Journal of Korean Academy of Nursing
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• v.25 no.4
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• pp.807-824
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• 1995

This study was intended to provide women who are experiencing menopause with effective nursing care by exploring the menopause experience. The purpose of the research was to understand the subjective feelings of women about the question of what the menopause experience is. Q-Methodological method was used for that purpose. As the research method, Q-statements were collected preliminary to the study of through in -depth interviews and a literature review. For the study 34 Q-statements were selected. There were 21 women as subjects for the research. The 21 women sorted the 34 statements using the principle of Forced Normal Distribution. The principle of Forced Normal Distribution, which has nine scales to measure the individual opinions, was called Q-Factor Analysis by using PC Quanl Program to supply the material. As a result, there were four categories(self-com-passion type, self-regulation type, self-perception type, self-abandonment type) of special opinion about the menopause experience in these women. The first type was called Self-compassion This type' was associated with varying degrees of emotonal instability(psychological withdrawal). And type in menopause signifies loss of a socially valued status and may result in depressive symptoms. This type expresses the menopause experience as associated with negative reaction. The second type is called Self-regulation. This type overcomes the menopause experience more actively than the other types and do not express the menopause experience as one of suffering. This type make efforts by themselves to regulate the mono-pause experience. The third type is called Self-perception. This type perceives the experience of menopause which as typical menopausal syndrome (hot flashes and decreased vaginal lubrication, decreased estrogen producing atrophic changes of the labia and vaginal mucosa, making intercourse uncomfortable). The fourth type is called Self- abandonment. This type denies the experience of menopause. The meaning of menopausal experience is significantly related with a life accident or life load. Also, This type experiences pain in the musculoskeletal system. As a result, The meaning of the menopausal experience is affected by perceived subjective experience of the nurses, the need to understand each persons meaning of the menopause experience and to develop appropriate nursing interventions based on the typology of menopause experience. Finally. The result of the study will provide basic data for nursing intervention the menopausal women.