• Title/Summary/Keyword: Index model

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A Numerical Analysis of Acoustic-Pressure Response of H2-Air Diffusion Flames with Application of Time-Lag Model (시간지연 모델의 적용을 통한 수소/공기 확산화염의 음향파 응답 분석)

  • Sohn, Chae-Hoon;Lim, Jun-Seok
    • Journal of the Korean Society of Propulsion Engineers
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    • v.16 no.1
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    • pp.1-8
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    • 2012
  • Acoustic-pressure response of diluted hydrogen-air diffusion flames is investigated numerically by adopting a fully unsteady analysis of flame structures in low and high pressure regimes. As acoustic frequency increases, finite-rate chemistry is enhanced through a nonlinear accumulation of heat release rate for any pressure regime, leading to a high amplification index. Same numerical results are analyzed with application of a pressure-sensitive time lag model, and thereby, interaction index and time lag are calculated for each pressure regime. The interaction index has the largest value in each pressure regime at an acoustic frequency near 1000 Hz. In a high-pressure regime, flames are more unstable than in a low-pressure regime. The interaction index shows a good agreement with the amplification index.

Developing and Comparing Site Index Curves Using Polymorphic and Anamorphic Equations for Douglas-fir (다변태(多變態)와 변태(變態) 방정식(方程式)을 이용(利用)한 미송(美松)의 지위지수(地位指數) 곡선(曲線) 추정(推定)과 비교(比較))

  • Lee, Sang Hyun
    • Journal of Korean Society of Forest Science
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    • v.88 no.2
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    • pp.142-148
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    • 1999
  • This research describes the construction of a site index equation and curves for Douglas-fir plantation (Pseudotsuga menziesii Mirb. Franco) in Nelson, New Zealand. The data sets of 146 Permanent Sample Plots (PSP) were used to build the model, and it was developed using the difference equation method. Parameter estimates were obtained using the non-linear routine of the SAS, PROC NLIN procedure. Of the models tested, a variant of the Schumacher polymorphic yield function showed the higher precision of fitting. About 95% of the observations used to fit the model could be predicted within ${\pm}1.2m$ of the actual values. Therefore, polymorphic family of site index curves, which reflect different shapes for the different site index classes, were derived from the Schumacher equation. It was found that the polymorphic site index equation was more accurate than the anamorphic equation in this study.

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Coffee Shops' Quality Classification and Customer Satisfaction Improvement Index by KANO Model (KANO모델을 활용한 커피전문점의 품질분류와 고객만족개선지수)

  • Shin, Bong-Sup;Kim, Ki-Suk
    • The Journal of the Korea Contents Association
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    • v.12 no.7
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    • pp.346-357
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    • 2012
  • This study classified the various quality features of coffee shop by Kano model with customers' perspective. Also both satisfaction coefficient and dissatisfaction coefficient are calculated to analyse the relative influence of quality features on customer satisfaction. This study also dragged the potential customer satisfaction improvement index to scrutinize the quality improvement possibility for coffee shops. The analysis results showed that low price, luxurious interior, restfulness of table and chair, usability of wireless internet are belonged to the Attractive quality. On the other hand, cleanliness and hygiene, quality to price are identified as the One-dimensional quality. The current satisfaction level for both 'Caffe Bene' and 'Starbucks' are measured to draw the potential customer satisfaction improvement index. The result showed that low price and quality to price appeared to be the highest in its quality improvement possibility. The findings of this study help understanding the quality features to focus on and strengthening the competitiveness for coffee shops.

A Study on Sensitivity Analysis by PDF in T7F Model (T7F Model에서 차량군분산계수변화에 따른 민감도분석에 관한 연구)

  • Hwang, Eui-Jin
    • Journal of Korean Society for Geospatial Information Science
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    • v.14 no.1 s.35
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    • pp.57-63
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    • 2006
  • The purpose of this study is to correct data on 3 intersection ranging from Kwangchun INT. to Nongsung INT. by the means of VTR recording and site survey and to measure the responsiveness of performance index by diversifying the platoon dispersion factor in signal progression simulation. The results are as follows : 1. The value of platoon dispersion factor was 0.28-0.33. The value in up stream is lower than that of in down stream even on the same intersection. 2. The platoon index showed big changes, though performance index didn't according to platoon dispersion factor. Therefore the value of platoon dispersion factor which is inner variable in T7F can be fixed for 0.34. 3. There was only little divergence in performance index changes according to platoon dispersion factor in designing the progression or T7F model.

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Appraisal of Farmland Potential Productivity Using GIS (GIS를 이용한 농지 잠재생산성평가)

  • 박승기;이창수
    • Spatial Information Research
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    • v.9 no.2
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    • pp.341-352
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    • 2001
  • This study was carried out to developed that appraisement model of Potential Productivity Index(PPI). PPI model was used Farmland Productivity Index(FPI) and Labor Productivity Index(LPI) by GIS, and PPI model applied to farm land consolidation region which has been completed recently. FPI was determined by overlapping Poly Grid of the soil properties at the analyzed project region. LPI was estimated by addition productive wages ratio of total direct productive cost. Addition productive wages determined by GIS Network analysis GIS Network analysis of working distance between farm house to paddy and each paddy. PPI variation of each the analyzed paddy of Masu and Weoncheon region was 0.967~0.780 respectively, and could be showed relative largely PPI value. PPI will provide basic element for large scaling and gathering of farm land and a substitute lot of farm land consolidation, and will be maximize productivity of paddy.

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Development and Application of an Evaluation Model for Biotope Appraisal in terms of Species and Biotope Preservation (종과 비오톱 보전을 위한 가치평가 모형 개발 및 적용)

  • Cho, Hyun-Ju;Lee, Hyun-Taek;SaGong, Jung-Hee;Ra, Jung-Hwa
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.13 no.5
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    • pp.59-80
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    • 2010
  • This research This research aims at developing systemic evaluation model in terms of biotope preservation through reports, literatures, and expert survey analysis by implementing biotope structure analysis in area level with selecting Hyunpoong and Yuga-myeon, Dalseong county, Daegu metropolitan city as a site. First of all, as a result of biotope type classification of research site, biotope type groups are classified into total 13, and its biotope types are divided into total 61. Also, as a result of literature analysis, total 18 items are drawn such as diversity of biotope typical species as a index item to assess the preservation value of biotope, and the first evaluation index are divided into 10 and the second ones are divided into 8 according to characteristic of index items. As a result of expert survey analysis, All 10 index items, first evaluation index, show high importance average (above 4.7). As a result of implementation of main cause for categorizing evaluation index by characteristic, there are 3 factors such as 'obstructive factor.' Based on above survey analysis result, as a result of estimating the weight of each item, 'restoration factor' showed the highest, 3.4541, but 'factor of habitat stability' showed 3.1468, which is the lowest The systemic value evaluation was set by comprehensively analyzing these results. As a result of biotope preservation value evaluation through applying research site, total 19 types which are abundant in vegetation are classified into I class, 12 types in II class, 5 types in III class, 10 types in IV class, and 15 types in V class respectively. Lastly, as a result of second evaluation, it is analyzed that there are 17 special meaningful space to preserve species and biotope(1a, 1b) and 61 meaningful space to preserve species (2a, 2b, 2c).

A Spatial Statistical Approach on the Correlation between Walkability Index and Urban Spatial Characteristics -Case Study on Two Administrative Districts, Busan- (도시 공간특성과 Walkability Index의 상관성에 관한 공간통계학적 접근 -부산광역시 2개 구를 대상으로-)

  • Choi, Don Jeong;Suh, Yong Cheol
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.32 no.4_1
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    • pp.343-351
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    • 2014
  • The correlation between regional Walkability Index and their physical socio-economic characteristics has evaluated by the spatial statistical analysis to understand the urban pedestrian environments, where has been emerging the significance, recently. Following to the study, the Walkability Indexes were calculated quantitatively from two administrative districts of Busan and measured Global Local spatial autocorrelation indices. Additionally, the Geographically Weighted Regression model was applied to define the correlation between Walkability Indexes and urban environmental variables. The spatial autocorrelation values and clusters on the Walkability Indexes were derived in statistically significant level. Furthermore, the Geographically Weighted Regression model has been derived more improved inference than the OLS regression model, so as the influence of local level pedestrian environment was identified. The results of this study suggest that the spatial statistical approach can be effective on quantitative assessing the pedestrian environment and navigating their associated factors.

Estimation of Site Index Equation for Pinus densiflora at Mt. Osu Region using Schnute Growth Function (Schnute 생장함수를 이용한 오서산지역 소나무림의 지위지수 추정)

  • Pyo, Jung-Kee;Lee, Young-Jin;Son, Yeong-Mo;Lee, Kyeong-Hak;Moon, Hyun-Shik
    • Journal of agriculture & life science
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    • v.43 no.4
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    • pp.9-14
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    • 2009
  • The purpose of this study was to estimate height growth pattern and to derive site index equation for Pinus densiflora grown at Mt. Osu region, Chungnam. A total of 21 repre - sentative trees from the established temporary plots around Boryeng and Cheongyang regions were destructively sampled to measure diameter, height, volume growth per 1-year interval by using of DTRS- 2000 measurement instrument. The Schnute growth function was select ed for height growth prediction using 181 height-age paired observations and derived anamorphic base age invariant site index curves (base index age 30 years). The fitted index and the asymptotic value of Schnute model indicated both 0.96 and 10.8 meter, respectively. The results suggested in this study could be very useful to understand the height growth pattern and productivity of the site quality on Pinus densiflora grown at Mt. Osu region, Chungnam.

Forecast of Korea Defense Expenditures based on Time Series Models

  • Park, Kyung Ok;Jung, Hye-Young
    • Communications for Statistical Applications and Methods
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    • v.22 no.1
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    • pp.31-40
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    • 2015
  • This study proposes a mathematical model that can forecast national defense expenditures. The ongoing European debt crisis weighs heavily on markets; consequently, government spending in many countries will be constrained. However, a forecasting model to predict military spending is acutely needed for South Korea because security threats still exist and the estimation of military spending at a reasonable level is closely related to economic growth. This study establishes two models: an Auto-Regressive Moving Average model (ARIMA) based on past military expenditures and Transfer Function model with the Gross Domestic Product (GDP), exchange rate and consumer price index as input time series. The proposed models use defense spending data as of 2012 to create defense expenditure forecasts up to 2025.

Uncertainty and Manufacturing Stock Market in Korea

  • Jeon, Ji-Hong
    • The Journal of Industrial Distribution & Business
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    • v.10 no.1
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    • pp.29-37
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    • 2019
  • Purpose - We study the dynamic linkages of the economic policy uncertainty (EPU) in the US on the manufacturing stock market returns in Korea. In detail, we examine the casual link between EPU index in the US and the manufacturing stock indexes in Korea. Research design, data, and methodology - We measure mainly the distribution effect of the US EPU on the manufacturing stock market in Korea of 1990-2017 by the vector error correction model (VECM). Result - In result, we estimate the impact of the US EPU index has significantly a negative response to the manufacturing stock market in Korea such as non-metal stock index, chemical stock index, food stock index, textile·clothes stock index, automobile·shipbuilding stock index, machinery stock index, steel·metal stock index. Also the remaining variables such as electric·electronics stock index, S&P 500, and producer price index in Korea have a negative relationship with US EPU index. Conclusions - We find out that the relationship between EPU index of the US and the manufacturing stock market in Korea has the negative relationships. We determine the EPU of the US has the spillover effect on the industry stock markets in Korea.