• Proceedings of the KIPE Conference
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• 2009.11a
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• pp.225-227
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• 2009

본 논문에서는 전압형 3상 ZSI(Z-source Inverter)의 입력전압과 커패시터 충전전압을 검출하고 ZSI의 기본 정의를 이용해 지령전압에 대한 변조지수(Modulation Index)를 결정하는 방법과 출력전압 제어가 가능한 변형된 SVM(공간벡터 변조방식)으로 구성된 알고리즘을 소개한다. 제안된 알고리즘은 ZSI의 이득과 변조지수의 정의를 이용한 간단한 방법으로 변조지수를 변화시켜 출력전압을 일정하게 유지하는 방법이다. PSIM을 통하여 타당성을 입증하였다.

• Journal of Oral Medicine and Pain
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• v.25 no.3
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• pp.315-323
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• 2000

측두하악장애의 치료에 이용되는 저주파 전자침 자극요법의 임상적 효과를 평가하기 위하여 치료를 시행한 28명과 치료를 전혀 시행하지 않은 10명의 대조군을 대상으로 치료전과 치료 2주 후에 경혈점의 압력통각역치와 임상지수를 측정하여 다음과 같은 결론을 얻었다. 1. 환자군에서 저주파 전자침 자극요법을 시행하기 전과 후의 임상지수가 유의하게 변화하였다(P<0.001). 2. 환자군에서 저주파 전자침 자극요법을 시행하기 전과 후의 압력통각역치는 G2, G21, Li4, S2, S3, S8, Si19 및 T17에서 유의하게 증가하였다(P<0.05). 3. 대조군에서 임상지수와 압력통각역치는 실험 전후에 차이가 없었다. 4. 환자군의 임상지수가 대조군에 비하여 유의하게 변화하였다 (P<0.05). 본 연구는 저주파 전자침 자극요법의 주관적 뿐만 아니라 임상적인 효과를 보여줌으로써 측두하악장애환자의 치료에서 저주파 전자침 자극요법이 유용한 방법임을 제시하였다.

• Applied Chemistry for Engineering
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• v.34 no.4
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• pp.388-396
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• 2023

The evaluation of fire risk for combustible materials was carried out using Chung's equations-X, Chung's equations-XI, and Chung's equation-XII, which were newly established. The fire risk index-XII (FRI-XII) and fire risk rating (FRR) were calculated for specimens including camphor tree, cherry, rubber tree, and elm. The combustion characteristics were determined using a cone calorimeter according to ISO 5660-1. Chung's equations caculated the fire performance index-X (FPI-X) and fire growth index-X (FGI-X) values ranged from 89.34 to 1696.75 s² /kW and from 0.0006 to 0.0107 kW/s² , respectively. In addition, the fire performance index-XI (FPI-XI) and fire growth index-XI (FGI-XI) varied from 0.08 to 1.48 and from 0.67 to 11.89, respectively. The fire risk index-XII (FRI-XII), which is an indicator of fire risk, showed that camphor tree had a value of 148.63 (fire risk rating: G), indicating a very high fire risk. This suggests that combustible materials with a high concentration of volatile organic compounds have lower FPI-X and FPI-XI values, higher FGI-X and FGI-XI values, and consequently higher FRI-XII values, indicating an increased fire risk.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.6 no.3
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• pp.43-49
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• 1992

Forecasting of electric power demand has been a basic element for electric power system operation and system development, and it's accuracy has very strong influence on reliability and economical efficience of power supply. So, in this paper, long―term maximum electric power demand has been forecasted by using the triple exponential smoothing method initiated R.G.Brown. It has been regarded this method as high accuracy and operational convenience. The smoothing function is a liner combination of all past observations and the weight given to previous observations decreases geometrically with age.

• Applied Chemistry for Engineering
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• v.33 no.4
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• pp.373-380
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• 2022

In this study, Chung's equations 1, 2, and 3 were extended to standardize smoke safety rating evaluation in case of fire, and Chung's equations-V, smoke performance index-V, and smoke growth index-V were calculated. Five types of wood were selected and their smoke indices were measured using the cone calorimeter method according to ISO 5660-1. The smoke risk was graded by the smoke risk index-VI according to Chung's equation-VI. Smoke risk index-VI increased in the order of PMMA (1) ≈ maple (1.01) < ash (1.57) < needle fir (4.98) < paulownia (46.15) < western red cedar (106.26). It was predicted that maple and ash had the lowest smoke risk, and paulownia and western red cedar had the highest. The five samples' CO mean production rate (COP_mean) was 0.0009~0.0024 g/s, indicating that these woods were incompletely burned than the polymethyl methacrylate (PMMA) reference material. Regarding the smoke properties of the chosen woods, the smoke performance index-V (SPI-V) increased as the bulk density increased, and the smoke risk index-VI (SRI-VI) decreased.

• Applied Chemistry for Engineering
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• v.34 no.2
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• pp.144-152
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• 2023

To evaluate the fire risk of combustible materials, Chung's equations VII, VIII, and IX were newly established. The fire risk index-IX (FRI-IX) and fire risk rating (FRR) were calculated. Ginkgo, dawn redwood, toona, lime, walnut, and polymethylmethacrylate (PMMA) were selected as test specimens. The combustion characteristics were evaluated using a cone calorimeter according to ISO 5660-1. After combustion, the fire performance index-VII (FPI-VII) of the specimens, varied between 15.15 and 182.53 s²/kW, as determined by Chung's equations, and the fire growth index-VII (FGI-VII) varied between 0.0023 and 0.0165 kW/s². The fire performance index-VIII (FPI-VIII) based on PMMA varied between 0.29 and 3.45, and the fire growth index-VIII (FGI-VIII) varied between 2.88 and 20.63. The FRI-IX, which is the fire risk rating, showed dawn redwood has a very high fire risk, with FRI-IX values of 71.14 (fire risk rating: G). Therefore, wood with a large amount of volatile organic compounds and a low bulk density showed a high value of FRI-IX by lowering FPI-VII and FPI-VIII and increasing FGI-VII and FGI-VIII.

• Asian Journal of Turfgrass Science
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• v.8 no.1
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• pp.19-24
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• 1994

낙동강 삼각주에 있는 Phragmites communis 초지에서 광차단과 흡수, 생산구조의 계절적 변화, 생산성 현존량을 1982, 1983 그리고 1993년에 각각 조사했다. 황충화된 수피를 통과하는 빛은 S자형으로 감소한다. 한 식물의 누층적 앞면적은, 그 시기의 수피의 잎면적 생장과 같다. 잎 면적이 log식에 따라 자랄 때, 잎면적의 수직적 누층은 일반적인 역동식에 의해 계산된다. 잎면적의 최대생장률에서의 광차단식은 식(1)에 의해 생산구조는 윗부분은 광합성계에 의해, 아래부분은 비광합성계에 의해 차지되어진다. 그러므로, 광차 단의 패턴은 S자형에서 지수함수적 패턴으로 변하게 된다. P.communis의 지상부 현존량은 $3,3660g/m^2$이상이었고, 순 생산성은 $142g/m^2$이었다. 갈초지대의 년중 순 생산은 각각 4.10,4.25,$4.47kg/m^2$/year 이었고, 촤대면적 지수는 각각 4.10.3,11.0,10.4이엇다. 이 결과는 일만초지보다 매우 높은 값이었다.

• Journal of the Korean Society for information Management
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• v.39 no.1
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• pp.1-15
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• 2022

This study analyzes the relationship of citations appearing in the patent data to understand knowledge transfers and impacts between patent documents in the field of pharmaceutical research. Patent data were collected from a website, Google Patents. The top 25 assignees were selected by searching for patent documents related to pharmaceutical research. We identify the citation relationships between assignees, then calculate and compare the values of h-index and derived indicators by using the number of citations and rank for each document of each assignee. As a result, in the case of pharmaceutical research, the assignee, such as 'Pfizer, MIT, and Abbott' shows a high impact. Among the five bibliometric indicators, the g-index and hS-index show similar results, and the indicators are the most related to the rankings of Total Citation Frequency, Cites per Patents, and Maximum Citation Frequency. In addition, it is highly related to the five indicators in the order of Total Citation Frequency, Cites per Patents, and Maximum Citation Frequency. In some cases, it is difficult to make an accurate comparison with Cites per Patents alone, which is previously known to indicate the technological influence of patent assignees.

• KSBB Journal
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• v.5 no.1
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• pp.75-80
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• 1990

The investigations of specific growth rate, specific alcohol production rate, cell yield, alcohol yield of K. marxianus LG were performed according to the sugar concentrations, 50, 80, 110, 190, and 250g/l of extracted solution of Jerusalem Artichoke. The functipnal relationship between specific growth rate, specific alcohol production rate, and alcohol concentrations were devoted study to. In case of low concentration of alcohol, the fuctions were linear relationships. But in the region of high concentration of alcohol, they expressed the exponential relationships. The growth rate of K. marxianus was prohibited at higher than 50g/l of alcohol concentrations regardless of concentration of residual sugar. Cell and alcohol yield showed the maximum values around 25g/l of alcohol concentraton without being related to initial sugar concentrations.

• Korean Journal of Weed Science
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• v.5 no.2
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• pp.155-163
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• 1985

Three pyrazole-herbicides, pyrazolate, pyrazoxyfene and benzophenap, were evaluated for their interaction in controlling barnyardgrass (Echinochloa crusgalli) with two chloroacetamide-herbicides, butachlor and pretilachlor. Percent inhibition of barnyardgrass growth by pyrazolate, pyrazoxyfene, and benzophenap was 44%, 64%, and 0%, respectively, when each was applied at the 1.5 leaf-stage of barnyardgrass at a rate of 3㎏ ai per ㏊ as single treatment, and the benzophenap showed 60% inhibition when it was applied at the coleoptile stage. While the lowest rate controlling the 1.5 leaf-stage barnyardgrasses by 98 to 100% of the butachlor and pretilachlor was 1.5㎏ and 200g per ㏊, respectively. All of the combinations of pyrazolate with butachlor, pyrazoxyfene with pretilachlor, and benzophenap with butachlor have shown synergistic interaction in controlling barnyardgrass on the Chisaka's isobole of 90% growth inhibition as well as on the Colby`s interaction efficacy data; synergism indices were 2.44, 1.62 and 1.52 in order. The dose combinations shown the maximal synergism were 1870g of pyrazolate with 140g of butachlor (1:0.075), 33008 of pyrazoxyfene with 338 of pretilachlor (1:0.01), and 3350g of benzophenap with 520g of butachlor (1:0.15) on the ai/㏊ basis.