• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.12
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• pp.3196-3204
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• 1996

We analyze the capacity of the imperfect power controlled DS/CDMA system with the Nakagami faded AMPS interferers by means of the analytical approach. Unlike the theoretical aassumption, the power control of the DS/CDMA system is not perfect. Therefore in this analysis we consider various parameters which cause the capacityreduction of the DS/CDMA system, the imperfect power control, the Nakagami fading index, he processing gain, and the number of AMPS interferers. The analytical results are compared with the Prasad's results which are considered only the imperfect power control of the DS/CDMA system. It is shown that the DS/CDMA capacity is decreased according to the increase of the deviation of the imperfect power control, to icrease the number pf the analog interfering users, and to decrease the processing gain.

• Journal of Society of Preventive Korean Medicine
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• v.20 no.3
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• pp.45-53
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• 2016

Objectives : The number of people in Mibyeong state that complain of physical and mental discomfort but without a clear medical diagnosis has rapidly increased, but the conventional medical system is insufficient to care for these people. By establishing an evaluation instrument for Mibyeong state, it will be possible to provide a research base for Mibyeong management system and expand the clinical area of integrative medicine. Methods : Mibyeong Index was designed to measure inconvenience and resilience of subject's complains including four physical symptoms (fatigue, pain, low sleep quality, indigestion) and mental distress include anxiety, anger, depression. A 21-item quality of healthy measure was developed and tested. We used results of a nation-wide stratified sampled adult data in Korea. Results and Conclusions : Mibyeong index had adequate internal consistency, Cronbach's alpha was 0.88 in general population(N=1,110). The correlation between establised quality of life questionnaires (including SF-12 and EQ-D5 VAS) and the Mibyeong index were from 0.468 to 0.493. The national promotion of advanced health for an aging society and original Mibyeong care technology based on traditional Korean medicine can be developed by a self-care system that enhancing health before suffering illness. We expect that this instrument could be contribute to health management of people in Mibyeong state.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.2
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• pp.157-166
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• 2004

Recently, switchboards for MV/LV distribution customers have been united and digitalized rapidly. This paper suggestes the effective information visualization method for the data mesured from cubicle switchboard for MV/LV distribution customers. We developed the algorithm that analyzes a large number of mesured data and displays them to users overall, such as fire index, power condition index, switchboard safety index, and power diminution index. Using a touch screen made users to operate it easily. User interface was also strengthened by taking graph visualization. We guess the information visualiztion method suggested in this paper shows the new direction that heavy electrical equipments including switchboards are going to develop in the future.

• Journal of the Optical Society of Korea
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• v.7 no.4
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• pp.234-239
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• 2003

Objective methods to assess quantitatively port wine stain (PWS) blanching in response to laser therapy are needed to improve laser therapeutic outcome. Previous studies have attempted to assess objectively PWS color based on point measurement devices. To date, these approaches have typically been limited by a number of factors such as small test area and need for contact. To address these issues, a polarization spectral imaging system and an image analysis method have been developed to evaluate quantitatively erythema and melanin content distribution in skin. The developed polarization spectral imaging system minimizes artifacts such as glaring, shadowing, and non-uniform illumination that interfere with image fidelity. Furthermore, the image analysis method has been employed to get images of skin melanin and erythema indices from the acquired color images for quantitative analysis. Finally, using PWS patient color image, the effectiveness in laser treatment of PWS was evaluated by calculating relative erythema index image that is the relative erythema index of PWS region to the normal region. The developed device and analysis method appears to be a simple and effective method for quantitative analysis of PWS blanching.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.3
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• pp.192-197
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• 2003

The ‘AEIPR’(Accelerometer Established Inertial Profiling Reference) method has been applied to measure the road profile. The dynamic road profiling method using AEIPR has the advantages of cost effectiveness, measuring speed and relatively high reliability. However, it is required to improve the double integration algorithm to get the measurement results with the accuracy of hither level. In the first part of this paper, the effective double integration algorithm is suggested and the ‘Road Profiler’ software is developed on the basis of the algorithm. Road profiling tests are performed using the developed ‘Road Profiler’ system on the specially designed tracks for the durability tests and the various types of pubic roads. Test results are shown and evaluated by the international road evaluation indicies and classification.

• The KIPS Transactions:PartD
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• v.8D no.5
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• pp.593-604
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• 2001

A database sharing system (DSS) refers to a system for high performance transaction processing. In the DSS, the processing nodes are coupled via a high speed network and share a common database at the disk level. Each node has a local memory and a separate copy of operating system. To reduce the number of disk accesses, the node caches data pages and index pages in its memory buffer. In general, B-tree index pages are accessed more often and thus cached at more processing nodes, than their corresponding data pages. There are also complicated operations in the B-tree such as Fetch, Fetch Next, Insertion and Deletion. Therefore, an efficient cache consistency scheme supporting high level concurrency is required. In this paper, we propose cache consistency schemes using identifiers of index pages and page_LSN of leaf page. The propose schemes can improve the system throughput by reducing the required message traffic between nodes and index re-traversal.

• Journal of Biosystems Engineering
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• v.16 no.3
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• pp.272-280
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• 1991

The aims of this study were to investigate the feasivility of analyzing a few sorting factors such as size, coloration and defect of apples with a monochrome image processing system and to find apparent properties which could be effectively used for apple sorting. The results are summarized as follows. 1. A computer program was made to analyze the projection area, coloration and defect of an apple with a monochrome image processing system. 2. The algorithm developed to compute the projedtion area of an apple was between on the proportional relation between a given reference area and the corresponding number of pixels, and the computing time was 0.74 to 0.82 second depending on the size of apple. 3. The coloration of an apple was expressed as the ratio of the gray value of a reference color to that of a given bounded area of the stem end surface (defined as coloration index), and the computing time was about 3.0 seconds with this algorithm. 4. Defect of an apple could be isolated by lowpass filtering and image subtraction but it took about 20 seconds in computing time. 5. The coloration of the Fuji apple could be classified into 3 to 4 groups by the coloration index and also, it was found that the correlation coefficient between the indices and sugar contents was 0.74. 6. The coloration index obtained from a given bounded area of the stem end side of the Fuji apple could represent the coloration of total surface with a correlation coefficient of 0.922.

• Journal of Astronomy and Space Sciences
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• v.36 no.3
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• pp.149-157
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• 2019

In this study, we investigate the associations between the solar variability and teleconnection indices, which influence atmospheric circulation and subsequently, the spatial distribution of the global pressure system. A study of the link between the Sun and a large-scale mode of climate variability, which may indirectly affect the Earth's climate and weather, is crucial because the feedbacks of solar variability to an autogenic or internal process should be considered with due care. We have calculated the normalized cross-correlations of the total sunspot area, the total sunspot number, and the solar North-South asymmetry with teleconnection indices. We have found that the Southern Oscillation Index (SOI) index is anti-correlated with both solar activity and the solar North-South asymmetry, with a ~3-year lag. This finding not only agrees with the fact that El $Ni{\tilde{n}}o$ episodes are likely to occur around the solar maximum, but also explains why tropical cyclones occurring in the solar maximum periods and in El $Ni{\tilde{n}}o$ periods appear similar. Conversely, other teleconnection indices, such as the Arctic Oscillation (AO) index, the Antarctic Oscillation (AAO) index, and the Pacific-North American (PNA) index, are weakly or only slightly correlated with solar activity, which emphasizes that response of terrestrial climate and weather to solar variability are local in space. It is also found that correlations between teleconnection indices and solar activity are as good as correlations resulting from the teleconnection indices themselves.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.2
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• pp.63-74
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• 2013

This study suggests that some of the negative arguments related to naturalized plants raised in academic discussions are unreasonable through an analysis of trends in the academia's research on naturalized plants in South Korea. A total of 117 academic papers related to "naturalized plants" on the Korean Studies Information Service System (KISS) website were re-classified by space, the number of vascular plant species, the number of naturalized plant species, naturalization index (NI), and urbanization index (UI). Correlation between human interference and naturalized plant distribution, and between sizes of conservation areas and naturalized plant distribution were analyzed. According to the results, while there was a tendency between urban population and UI ($r^2$ = 0.70, p = .000), the number of visitors in national parks had no relation to either the NI or the UI (r = 0.028 and r = 0.013, respectively). Likewise, there was no correlation between national parks or conservation areas and naturalized plant distribution (r = 0.014, r = 0.17, respectively). The average NI and the UI of forest areas were approximately twice as low as those of national parks. In estimated regression equation, when one hypothesizes that the entire 4,952 taxa of plants growing in South Korea, the number of naturalized plants, combining paleo-naturalized plants and neo-naturalized plants, amounted to 2,398 taxa, 48.43%. In the academia, Korean Endemic Plants are less than one quarter of 4,952 taxa. Such results signify that, contrary to discussions in the academia, it is meaningless to distinguish between naturalized plants and native plants. In certain aspects, academic discussions on naturalized plants in Korea have proceeded in a manner similar to cultural exclusion by mono-culturalism in a multi-cultural environment.

• 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.