• Journal of Electrical Engineering and Technology
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• 제7권6호
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• pp.834-844
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• 2012

Nonlinear electronic loads draw harmonic currents from the power grids that can cause energy loss, miss-operation of power equipment, and other serious problems in the power grids. This paper proposes a harmonic compensation method using multiple distributed resources (DRs) such as small distributed generators (DGs) and battery energy storage systems (BESSs) that are integrated to the power grids through power inverters. For harmonic compensation, DRs should inject additional apparent power to the grids so that certain DRs, especially operated in proximity to their rated power, may possibly reach their maximum current limits. Therefore, intelligent coordination methods of multiple DRs are required for efficient harmonic current compensation considering the power margins of DRs, energy cost, and the battery state-of-charge. The proposed method is based on fuzzy multi-objective optimization so that DRs can cooperate with other DRs to eliminate harmonic currents with optimizing mutually conflicting multi-objectives.

• 동의신경정신과학회지
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• 제12권2호
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• pp.185-191
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• 2001

Objectives: This study aimed to evaluate the usefulness as a screening test of Clock Drawing Test(CDT) compared with the standard K-DRS in probably dementia. Methods: The subjects for this study consisted of 19 elderly persons who visited to the outpatient department of Oriental Neuropsychiatry of the Kyunghee Oriental hospital. They received the K-DRS and the Clock Drawing Test. Three observers evaluated them with circle, numbers, hands. Inter-rater reliability of scores from Clock Drawing Test was assessed and Pearson correlation coefficients were used to examined the relationships between scores from Clock Drawing Test and K-DRS. Results: Correlations between individual raters was highly significant (r= .957, .974, and .970, respectively: p<.001). There was stastically significant correlations between K-DRS and CDT scores (r= 0.849, p<.001). Conclusions: The CDT can be rated reliably by observers and correlations between CDT and K-DRS is significantly high. We confirmed the usefulness of CDT as simple, easily administered, low cost, and reliable general screening test for dementia.

• 동의신경정신과학회지
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• 제14권1호
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• pp.17-26
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• 2003

Objective : The clinical efficacy of Jowiseungchungtang(oriental herbal medication) over 6-month on the cognitive function in patients with mild Dementia of Alzheimer type(DAT) was investigated in this study. Method : The subjects for this study consisted of dementia patients who visited to the outpatient dementia department of Oriental Neuropsychiatry of the Kyunghee Oriental hospital. Patients were required to have at entry: a dignosis of mild DAT; Biochemical test, CBC, Urine analysis, Chest X -ray, EKG, Brain- MRI, Mini-Mental States-Korea(MMSE-K), Korean-Dementia Rating Scale(K-DRS), Samsung Dementia Questionaire(SDQ;to their caregiver). Patients(n=31) were assigned to treatment with Jowiseungchungtang (fourth/day for 6-month). The primary outcome measure was K-DRS. Result : 1. Patients' mean age was $71.4{\pm}6.6$ years(range 59 to 86 years). 2. Patients' mean education was $6.1{\pm}4.9$ years. K-DRS scores at baseline was $110.5{\pm}12.2$. K-DRS scores at 6-month was $109.0{\pm}17.0$. K-DRS scores at 6-month was not significantly different with K-DRS scores at baseline(t=.791 r=.435 p<.05). Conclusion : Treatment with Jowiseungchungtang for 6-month protected the cognitive function decline in patients with mild DAT.

• 한국수산과학회지
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• 제39권4호
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• pp.313-317
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• 2006

To prepare oligouronic acids from high-molecular-weight alginates, sea tangle (Laminaria japonica) alginates were hydrolyzed at various pHs for 1 hr at 80$^{\circ}C$. The effects of hydrolysis pH (HpH) on the average molecular weight (AMW) and MW distribution ratios (DRs) in the hydrolyzed alginates were investigated. As HpH decreased, the DRs of the alginates with MW>500 kDa and MW=300-500 kDa decreased exponentially, while it increased exponentially for MW<50 kDa. For MW=100-300 kDa, DR increased exponentially as HpH fell from 5.0 to 3.5, and then decreased exponentially. Similarly, for MW=50-100 kDa, DR increased exponentially as HpH increased to 1.0 from 5.0, and then decreased exponentially. As HpH decreased, the MW cutoff size and AMW of alginates fraction with the highest DR were decreased. For HpH 4.5 and 5.0, the MW cutoff size with the highest DRs was MW=300-500 kDa; the DRs were 28.9 and 32.6%, respectively; and the AMW of both was about 400 kDa, for HpH 3.5 and 4.0, the cutoff size was MW=100-300 kDa; the DRs were about 28%: and the AMWs were both about 200 kDa. For HpH 3.0, the cutoff size was MW=50-100; the DR was 29.0%; and the AMW was 73 kDa. For HpH values below 2.0, the MW cutoff size with the highest DRs was MW<50 kDa, and all of the AMWs were below 28 kDa.

• 동의신경정신과학회지
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• 제15권2호
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• pp.141-148
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• 2004

Objective : This study is designed to assess the effects of Gongjin-dan on cognitive decline of the patients with mild Dementia of Alzheimer Type(DAT). Method : 33 patients with mild DAT were measured by using K-DRS, and after 100 days again. During 100 days the patients with mild DAT were treated with Gongjin-dan. The scores of K-DRS between before and after treatment were analyzed by paired t-Test. Result : 1. the mean age of patients was $70.3{\pm}4.1$ years (range 65 to 84 years) 2. the mean education of patients was $5.5{\pm}5.3$ years 3. the mean K-DRS score of the patients before treatment was $93.2{\pm}12.1$, and the mean K-DRS score of the patients after treatment was $114.7{\pm}14.5$. K-DRS scores after treatment was significantly different with the K-DRS scores before treatment.(t=9.907, r=.573, p<.00l) Conclusion : Treatment with Gongjin-dan for 100 days increased the cognitive ability in patients with mild DAT

• 동의신경정신과학회지
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• 제17권3호
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• pp.11-19
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• 2006

Objective : This study was to investigate the utility and relation of dementia rating test(K-DRS and IADL, NPI-Q(symptom), NPI-Q(suffering), CCDR, SDS Method : For this study, we carried out dementia assessment examination of 34 patients with memory disturbance who have come to Cheongju oriental hospital of Daejeon university from April 2005 to February 2006. This study classified the patients as none-dementia(ND), questionable dementia(QD), and dementia(DA) groups and analyzed the result of examination. Results: 1. K-DRS and SDS, K-DRS and SDS, NPI-Q(symptom) and NPI-Q(suffering), NPI-Q(symptom) and CCDR showed clear correlations statistically each other. 2. K-DRS scores showed the significant differences from that of ND and the other groups ; attention and conceptualization showed the significant differences between ND and DA, management and memorization showed the significant differences between DA and the other groups. 3. IADL scores showed the significant differences from that of DA and the other groups, NPI-Q(symptom) scores showed the significant differences between QD and DA, NPI-Q(suffering) scores showed no differences among all groups. 4. CCDR scores showed the significant differences from that of DA and the other groups, SDS scores showed the significant differences between ND and DA 5. MMSE- K and K-DRS showed strong correlations statistically each other. Conclusion : The study results suggest that dementia rating tests is useful to esteem the dementia and the dementia rating tests have strong corelations each other. We use the above mentioned tests for correct diagnosis.

• Advances in Energy Research
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• 제3권2호
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• pp.81-95
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• 2015

Microgrid, which can be considered as an integration of various dispersed resources (DRs), is characterized by number of DRs interfaced through the power electronics converters. The microgrid comprising these DRs is often operated in an islanded mode. To minimize the cost, reduce complexity and increase reliability, it is preferred to avoid any communication channel between them. Consequently, the droop control method is traditionally adopted to distribute active and reactive power among the DRs operating in parallel. However, the accuracy of distribution of active and reactive power among the DRs controlled by the conventional droop control approach is highly dependent on the value of line impedance, R/X i.e., resistance to reactance ratio of the line, voltage setting of inverters etc. The limitations of the conventional droop control approach are demonstrated and a modified droop control approach to reduce the effect of impedance mis-match and improve the time response is proposed. The error in reactive power sharing is minimized by inserting virtual impedance in line with the inverters to remove the mis-match in impedance. The improved time response is achieved by modifying the real-power frequency droop using arctan function. Simulations results are presented to validate the effectiveness of the control approach.

• 동의신경정신과학회지
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• 제14권2호
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• pp.43-59
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• 2003

Object : This study was designed to assess the protective effects of Jowiseungchungtang on cognitive decline of the patients with early DAT[Dementia of Alzheimer Type]. Method : 15 patients with early DAT and 10 healthy elderly subjects were measured by using auditory ERP and K-DRS, and after 9 months again. During 9 months the patients with early DAT were administered with Jowiseungchungtang. Result : 1. The score of K-DRS increased in two group but it was not significant. 2. The latency of ERP P300 component increased in 2nd test of the normal group, but did not increase in 2nd test of patients group. 3. The amplitude of ERP P300 component showed the significant difference in electrode location in patients group, but it did not show any typical property. Conclusion : The results suggest that Jowiseungchungtang may have protective effects on cognitive decline in the patients with early DAT.

• Journal of Contemporary Eastern Asia
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• 제14권2호
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• pp.17-36
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• 2015

As an effort of mitigating hazards, pro-environmental programs have been vigorously activated with regard to solid waste recycling. It is beneficial for both the environment and resource saving, but implementation and enforcement are hard to achieve voluntarily. The South Korean Government first implemented the Deposit Refund System (DRS) and later the Extended Producer Responsibility Program (EPR) to reduce waste and encourage recycling in South Korea. Un-der the DRS, producers would pay for recycling the wastes of the products. The government then repealed the DRS and implemented the EPR program. Under this program, the producers recycle as much as the Ministry of Environment determines or pay a penalty for an excessive amount of the waste. In the broader perspective of disaster management, such policy programs can mitigate environmental hazards. This paper compares those two programs that facilitated the level of recycling, focusing on how such programs regulate producers and how they were operated from the perspective of implementation and enforcement.

• 한국언어정보학회지:언어와정보
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• 제12권1호
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• pp.1-26
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• 2008

This paper proposes a dynamic approach to anaphoric resolution in conjunction phrases, in terms of Discourse Representation Theory. Unlike Kamp, van Genabith, and Reyle (forthcomming)'s analysis, it proposes two different types of discourse representation structures for conjunction phrases; one for coordinate phrases such as and conjunction phrases and the other one for subordination conjunction phrases such as when subordination phrases. Following Chung (1992), Chung (2004), every element is processed in the order of occurrence and conjunction operators in a non-sentence-initial position cause the ongoing DR to split in two with the same index. DRS conditions and accessibility are accordingly modified so that DRs for conjunction clauses can be accessible from DRs for main clauses.