• Journal of Power Electronics
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• v.17 no.1
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• pp.222-231
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• 2017

In this paper, a new architecture for a cost-effective power conditioning systems (PCS) using a single-sourced asymmetric cascaded H-bridge multilevel inverter (MLI) for photovoltaic (PV) applications is proposed. The asymmetric MLI topology has a reduced number of parts compared to the symmetrical type for the same number of voltage level. However, the modulation index threshold related to the drop in the number of levels of the inverter output is higher than that of the symmetrical MLI. This problem results in a modulation index limitation which is relatively higher than that of the symmetrical MLI. Hence, an extra voltage pre-regulator becomes a necessary component in the PCS under a wide operating bias variation. In addition to pre-stage voltage regulation for the constant MLI dc-links, another auxiliary pre-regulator should provide isolation and voltage balance among the multiple H-bridge cells in the asymmetrical MLI as well as the symmetrical ones. The proposed PCS uses a single-ended DC-DC converter topology with a coupled inductor and charge-pump circuit to satisfy all of the aforementioned requirements. Since the proposed integrated-type voltage pre-regulator circuit uses only a single MOSFET switch and a single magnetic component, the size and cost of the PCS is an optimal trade-off. In addition, the voltage balance between the separate H-bridge cells is automatically maintained by the number of turns in the coupled inductor transformer regardless of the duty cycle, which eliminates the need for an extra voltage regulator for the auxiliary H-bridge in MLIs. The voltage balance is also maintained under the discontinuous conduction mode (DCM). Thus, the PCS is also operational during light load conditions. The proposed architecture can apply the module-integrated converter (MIC) concept to perform distributed MPPT. The proposed architecture is analyzed and verified for a 7-level asymmetric MLI, using simulation results and a hardware implementation.

• Journal of Families and Better Life
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• v.5 no.2
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• pp.11-27
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• 1987

This study examined job satisfaction levels between employed single women and employed married women. The specific objectives of this study were; (1) to investigate differences in the level of job satisfaction between employed single women and employed married women; (2)to investigate the factors which influence the level of job satisfaction; (3)to investigate the relationship between job satisfaction and life satisfaction. the data used in this study included 441 working women from 290 (65.8 %) single women and 151 (34.2%) married women. Statistical analyses were conducted using frequencies, percentiles, mean , t-test , ANOVA, pearson's correlation and a stepwise multiple regression. The major findings were ; (1) at the P<.005 level, there was a significant difference in the job Satisfaction Index (JSI) between employed single and married women by using the t-test ; (2) Occupation, type of organization , job experiences, travel time from home to work. unionization, age, and health status were significantly related to the JSI by using the one-way ANOVA; (3) Thee was an interaction effect between income and marital status on the JSI, and between education and marital status on the JSI; (4) Using a stepwise multiple regression method, the order of variables as they were entered in the model were different between employed single and married women; (5) There was a positive relationship between the JSI and Life Satisfaction Index(r=.41)

• Journal of the Korea Society of Computer and Information
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• v.12 no.4
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• pp.209-219
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• 2007

Since 100PPM Quality Certification System has been established by the Industrial Advancement Administration in 1995, 100PPM duality Innovation movement has contributed much to the enhancement of qualify competitiveness of Korea's parts industry. And in 2000, raised to a higher level, Single PPM qualify Certification System has been established by the Small and Medium Business Adminstration. The quality target is below the 10ppm(parts per million) in outgoing qualify and delivered goods plus field claim. Recently 1.818 companies is received Single PPM Quality Certification from Government. Single PPM Quality Innovation movement is perfection movement which is suitable for 21C's social-economical criteria to pursuit of zero defect. The purpose of this study is to suggest the Kano Model based Global Sustainable duality Innovation(GSQI) Index to improve current problems of Single PPM Quality Innovation Movement.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.1
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• pp.127-132
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• 2014

This study is concerned with process capability index in single process. We enumerated issues on the calculation of process capability index and described the effects of these issues. We explained the development process and the reason of the representative existing process capability indices. We investigated whether the indices agree with the concept of process capability and drew the problems from those results. In addition, we proposed alternative and direction to seize the process capability necessary to the field.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.4
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• pp.69-75
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• 1999

This study was performed to investigated the application of mixed resins for corrugated container board. The corrugated container board yields a sandwich structure in which a linerboard material is glued to a corrugated medium . Now, manufacturing corrugated container boards don't provide sufficient strength, and result in box failure during shipping . Therefore improvement of box strength is necessary . In this study, we intend to improve box strength by improving corrugated medium strength with mixed resins and to find the optimum treatment condition of this resins. First, we tried to mixed resins as Starch+CMC, Starch_Irea, CMC+Urea, Second, investigated to applicability of this resins for corrugated medium , and the third, measured tensile index, burst index, and edgewise compression index on liner, medium paper, and single faced corrugated container board. In this test results, we obtained that the improvement ratios of tensile index in liner and medium paper were approximately 80-185%, 60-118% , respectively. The respecting improvement ratios of edgewise compression index of single faced corrugated container board was approximately 91-124%, relatively. In addition, we concluded that optimum condition in mixing ratio was 1 :3 with CMC + Urea and the ap[plication amounts was 9% on materials. Fro manufacture of corrugated container board, optimum condition in mixing ratio was 1 : 3 with 5% CMC +Urea , because of considering to improvement of strength on cost.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.05a
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• pp.51-54
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• 2005

This paper proposes an index structure which is used to process X-Path on S-XML data. There are many previous index structures based on tree structure for X-Path processing. Because of general tree index's top-down query fashion, the unnecessary node traversal makes heavy access and decreases the query processing performance. And both of the two query types for X-Path called single-path query and branching query need to be supported in proposed index structure. This method uses a combination of path summary and the node indexing. First, it manages hashing on hierarchy elements which are presented in tag in S-XML. Second, array blocks named path summary array is created in each node of hashing to store the path information. The X-Path processing finds the tag element using hashing and checks array blocks in each node to determine the path of query's result. Based on this structure, it supports both single-path query and branching path query and improves the X-Path processing performance.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.17 no.3
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• pp.253-262
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• 2013

Objectives This study is on the quantifying method for the acupuncture-moxa cautery heat response index, which are based on the some definitions. Methods The magnitude of the acupuncture-moxa cautery is defined by the pain-feeling of the acupuncture-moxa cautery stimulation: the stimulation magnitude of the acupuncture is 1, that of the direct moxa-cautery is 2, and that of the indirect moxa-cautery is 0.5. The heat variation of the acupuncture-moxa cautery stimulation is defined by the heat variations of the characteristic points pre/post-stimulations in the stenosis of the lumber. The acupuncture-moxa cautery heat response index is defined by the ratio of between the magnitude of the heat variation and the natural logarithmic magnitude of the stimulation. Results With the respect of the acupuncture-moxa cautery heat response index, I experimented and estimated 4 types of stimulations in the stenosis of the lumber: the single acupuncture stimulation with 40%, the single direct moxa-cautery stimulation with 52%, the combinational acupuncture-moxa cautery stimulations with 27%, and the combinational acupuncture-indirect electronic moxa-cautery stimulations with 53%. Conclusions According to the acupuncture-moxa cautery heat response index. the combinational acupuncture-moxa cautery stimulations especially need to be changed to the combinational acupuncture-indirect electronic moxa-cautery stimulations.

• Journal of the Korean Society for information Management
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• v.32 no.4
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• pp.205-221
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• 2015

The impact of a journal is commonly used as the impact of an individual paper within that journal. It is problematic to interpret a journal's impact as a single paper's impact of the journal, so there are several researches to measure a single paper's impact with its own citation counts. This study applied 8 impact indicators to Korean Citation Index database and examined discipline bias of each indicator. Analyzed indicators are simple citation counts, PageRank, f-value, CCI, c-index, single publication h-index, single publication hs-index, and cl-index. PageRank has the least discipline bias at highly ranked papers and journal bias in a discipline. On the contrary, simple citation counts showed strongly biased results toward a certain discipline or a journal. KCI database provides only simple citation counts. It needs to show PageRank (global indicator) to discover influential papers in diverse areas. Furthermore it needs to consider to provide the best of local indicators. Local indicators can be calculated only with papers in users' search results because they uses citation counts of citing papers and the number of references. They are more efficient than global indicators which explore the whole database. KCI should also consider to provide Cl-index (local indicator).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.6
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• pp.4131-4136
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• 2015

This paper compares and calculates more precisely the averaged reflectance of antireflection coating with different structure of single and 6 layer assuming the incident angle of light changing from $8^{\circ}$ to $60^{\circ}$ not like normal incidence as usual case. The reflectivity of AR coating of 6 layers with 180 nm thickness having index profile suggested as linear and quintic function and single layer with same thickness having even index are calculated and compared, when the wavelength of incident light ranges from 400 nm to 1200 nm. As the results the AR coating with 6 layers having quintic(linear) function index profile shows the lower reflectance about 11.6 %(14.6 %) than other index profiles, which is approximately 8 % lower reflectance compared with single layer case(about 19.6 %). This results could be applied for the better antireflection coating design applying to optical devices and filters.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.15 no.2
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• pp.80-87
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• 2009

Purpose: This study was to determine the effects of a early exercise program on the pain, disability and balance after single-level lumbar discectomy. Methods: Forty patients were randomized into experimental(N=20) and control(N=20) groups. Three days after surgery, patients in the experimental group undertook a 4-week exercise program. Assessments were performed in all patients during the week before surgery and at 4 weeks after. The assessment included measures of back and leg pain(VAS), Oswestry disability index(ODI), stability index(SI) and weight distribution index(WDI). Results: At 4 weeks, VAS, ODI, SI, WDI were significantly reduced in both groups(p<.01). Also the experimental group was significantly reduced back and leg pain(VAS), ODI and WDI were better than the control group(p<.05). Conclusion: It seems that early exercise program is more effective in patients who undergo single-level lumbar discectomy.