• Title/Summary/Keyword: regression equations

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Economic Rationale of Compensating Balance Requirements and Its Impact on Money Supply (「꺾기」의 경제학(經濟學)과 통화량(通貨量) 효과분석(效果分析))

  • Jwa, Sung-hee
    • KDI Journal of Economic Policy
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    • v.14 no.1
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    • pp.89-119
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    • 1992
  • This paper purports to analyze the economic rationale of compensating balance requirements and its impact on money supply. This practice has recently been severely criticized for artificially increasing the money supply and, therefore, limiting the nation's aggregate lending policy under the tight constraint of the given money supply target. A review of the existing literature implies that compensating balance requirements is a banking practice which leads to corrections in the distortion of financial resource allocation due to the imperfection of financial market stemming from asymmetric information and/or financial regulations on deposit and lending rates. Therefore, the economic rationale of this practice is deemed to improve the efficiency of financial resource allocation. On the other hand, the macroeconomic impact of compensating balance requirements on the money supply depends on the impact on the money multiplier, which in turn depends on the desired ratio of deposit that people wish to maintain on the money borrowed from the banking system, and on the desired reserve ratio that the banking system would like to hold for deposit withdrawal. If the compensating balance requirements could increase the desired ratio of deposit to borrowing (bank lending), it will increase the available amount of total reserve within the banking system and, in turn, the money multiplier. However, this channel has not been fully analyzed in the literature, and the direction of the effect is ambiguous. If the practice could reduce the turn-over rate of deposit and, thereby, reduce the desired reserve ratio of the banking system, then it will also increase the money multiplier. While this channel operates unambiguously toward increasing the money multiplier, this effect will be limited by the extent that the banking system holds the excess reserve over the required reserve because the excess reserve will set the maximum amount for the desired reserve to fall. This paper tries to determine the effect on the money supply by empirically estimating the multiplier and the desired ratio of deposit to lending equations as functions of the ratio of compensating balance to the related lending, which is not observable and is estimated for the regression purpose. The results suggest that the effect of compensating balance requirements on the money supply in Korea does not exist or is very tenuous even if it could operate. Therefore, this paper concludes that the well publicized policy of cross cancelling the compensating balance and the related lending will not be effective at controlling the money supply and increasing the amount of loans without expanding the money supply.

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Optimization of Microwave-Assisted Process for Extraction of Effective Components from Mosla dinthera M. (마이크로파 추출공정에 의한 쥐깨풀 유용성분의 추출조건 최적화)

  • Lee Eun-Jin;Kwon Young-Ju;Noh Jung-Eun;Lee Jeong-Eun;Lee Sung-Ho;Kim Jae-Keun;Kim Kwang-Soo;Choi Yong-Hee;Kwon Joong-Ho
    • Food Science and Preservation
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    • v.12 no.6
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    • pp.617-623
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    • 2005
  • Response surface methodology (RSM) was applied to microwave-assisted process (MAP) extraction for effective components from Mosla dianthera M. Microwave power (2,450 MHz, 0-160 W) and extraction time (1-5 min) were used as independent variables ($X_i$) for central composite design to yield 10 different extraction conditions. Optimum conditions were predicted for dependent variables of $75\%$ ethanol extracts, such as total yield($Y_1$), total phenolics($Y_2$), total flavonoids($Y_3$), and electron donation ability($Y_4$, EDA). Determination coefficients ($R^2$) of regression equations for dependent variables ranged from 0.8397 to 0.9801, and microwave power was observed to be more influential than extraction time in MAP. The maximal values of each dependent variable predicted at different extraction conditions of microwave power (W) and extraction time (min) were as follows; $6.76\%$ of total yield at 142.00 W and 4.36 min, 78.68 mg/g of total phenolics at 136.78 W and 4.40 min, 6.75 mg/g of total flavonoids at 159,69 W and 3.17 min, and $49.81\%$ of EDA at 133.87 W and 4.47 min, respectively. The superimposed contour maps for maximizing dependent variables illustrated the MAP conditions of 79 to 113 W in power and of 2.73 to 3.84 min in extraction time.

Normal Predictive Values of Spirometry in Korean Population (한국인의 정상 폐활량 예측치)

  • Choi, Jung Keun;Paek, Domyung;Lee, Jeoung Oh
    • Tuberculosis and Respiratory Diseases
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    • v.58 no.3
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    • pp.230-242
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    • 2005
  • Background : Spirometry should be compared with the normal predictive values obtained from the same population using the same procedures, because different ethnicity and different procedures are known to influence the spirometry results. This study was performed to obtain the normal predictive values of the Forced Vital Capacity(FVC), Forced Expiratory Volume in 1 Second($FEV_1$), Forced Expiratory Volume in 6 Seconds($FEV_6$), and $FEV_1/FVC$ for a representative Korean population. Methods : Based on the 2000 Population Census of the National Statistical Office of Korea, stratified random sampling was carried out to obtain representative samples of the Korean population. This study was performed as a part of the National Health and Nutrition Survey of Korea in 2001. The lung function was measured using the standardized methods and protocols recommended by the American Thoracic Society. Among those 4,816 subjects who had performed spirometry performed, there was a total of 1,212 nonsmokers (206 males and 1,006 females) with no significant history of respiratory diseases and symptoms, with clear chest X-rays, and with no significant exposure to respiratory hazards subjects. Their residence and age distribution was representative of the whole nation. Mixed effect models were examined based on the Akaike's information criteria in statistical analysis, and those variables common to both genders were analyzed by regression analysis to obtain the final equations. Results : The variables affecting the normal predicted values of the FVC and $FEV_6$ for males and females were $age^2$, height, and weight. The variables affecting the normal predicted values of the $FEV_1$ for males and females were $age^2$, and height. The variables affecting the normal predicted values of the $FEV_1/FVC$ for male and female were age and height. Conclusion : The predicted values of the FVC and $FEV_1$ was higher in this study than in other Korean or foreign studies, even though the difference was < 10%. When compared with those predicted values for Caucasian populations, the study results were actually comparable or higher, which might be due to the stricter criteria of the normal population and the systemic quality controls applied to the whole study procedures together with the rapid physical growth of the younger generations in Korea.

Investigation of Factors on the Sensory Characteristics of Milk Bread with Tumeric Powder (Curcuma longa L.) Using Fractional Factorial Design Method (부분배치법을 활용한 울금 분말 첨가 우유식빵의 관능적 영향 인자 탐색)

  • Jung, Kyong Im;Park, Jae Ha;Kim, Mi Jeong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.4
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    • pp.592-603
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    • 2014
  • We developed various recipes of turmeric powder (Curcuma longa L.) added to milk bread and assessed the individual effects of seven ingredients [milk ($X_1$), turmeric powder ($X_2$), bread improver ($X_3$), fresh yeast ($X_4$), butter ($X_5$), sugar ($X_6$), and salt ($X_7$)] as well as the 2-way interaction effects of the ingredients on the sensory characteristics of breads using fractional factorial design method. The center and end points of each component were determined via literature review and multiple test baking. Seven trained sensory test panels evaluated the outside appearance (OA), inside appearance (IA), and flavor & texture (FT) of 38 breads using 46 items of sensory evaluation. Findings are as follows: for the OA, $X_1$ (P<0.05) and $X_4$ (P<0.0001) exhibited significant individual effects, whereas $X_1*X_7$, $X_2*X_5$, $X_3*X_6$, and $X_4*X_6$ indicated significant interaction effects (P<0.05). For the IA, $X_1$ (P<0.0001), $X_4$ (P<0.0001), $X_6$ (P<0.05), $X_2*X_4$ (P<0.05), and $X_3*X_6$ (P<0.01) showed individual and interaction effects, respectively. For the FT, $X_1$ and $X_2$ showed the most significant individual effect (P<0.0001), followed by $X_4$, $X_5$ and $X_6$ (P<0.05) in descending order. $X_4*X_7$ indicated the only significant interaction effect. We computed the magnitudes of the 2-way interaction effects of the ingredients with a distinct emphasis. Model equations predicting the levels of the ingredient effects on the breads were also provided via regression analyses. In summation, $X_4$ appeared to be the most significant component affecting the sensory characteristics based on its individual and 2-way interaction effects. Further, $X_6$, $X_1$, $X_2$, and $X_5$ indicated both individual and interaction effects. $X_3$ and X7 showed only interaction effects. The center point effect appeared to be unequivocal for whole sensory characteristics. Findings of the present study may provide insights into the selection of ingredients to derive an optimal model for turmeric powder-added bread using the response surface method hereafter.

Optimization of Microwave Extraction Conditions for Antioxidant Phenolic Compounds from Ligustrum lucidum Aiton Using Response Surface Methodology (반응표면분석법을 이용한 여정자의 페놀계 항산화 성분에 대한 마이크로웨이브 추출조건 최적화)

  • Yun, Sat-Byul;Lee, Yuri;Lee, Nam Keun;Jeong, Eung-Jeong;Jeong, Yong-Seob
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.4
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    • pp.570-576
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    • 2014
  • Response surface methodology (RSM) was applied to optimize the microwave-assisted extraction (MAE) conditions for electron-donating ability, total phenol content, and total flavonoid content of Ligustrum lucidum Aiton. Ligustrum lucidum Aiton from different regions was tested, and Ligustrum lucidum Aiton from Haenam was chosen due to its higher total phenolic content, total flavonoid content, DPPH radical scavenging activity and ABTS radical scavenging activity compared to the other samples. Central composite design was used to optimize extraction of Ligustrum lucidum Aiton from Haenam as well as determine the effects of extraction temperature ($X_1$) and extraction time ($X_2$) on dependent variables ($Y_n$). Determination coefficients ($R^2$) of the regression equations for dependent variables ranged from 0.8858 to 0.9517. The optimum points were $131.68^{\circ}C$ for extraction temperature and 5.49 min for extraction time. Predicted values of the optimized conditions were acceptable when compared to experimental values.

Characterization of Symptom and Determination of Tissue Critical Concentration for Diagnostic Criteria in 'Maehyang' Strawberry (Fragaria $\times$ ananassa Duch.) as Influenced by Calcium Concentrations in the Fertigation Solution ('매향' 딸기의 칼슘 영양진단을 위한 결핍증상 및 식물체 내 한계농도)

  • Choi, Jong-Myung;Jeong, Suck-Kee;Yoon, Moo-Kyung
    • Journal of Bio-Environment Control
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    • v.17 no.3
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    • pp.231-237
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    • 2008
  • Objective of this research was to investigate the effect of calcium concentrations in the fertilizer solution on growth and development of Ca deficiency in 'Maehyang' strawberry (Fragaria $\times$ ananassa Duch.). The margins of the youngest leaves were scorched and they developed a cupped shape as they were expanded in Ca deficient plants. The vein area of the youngest leaves became brown when the deficiency became severe. The quadratic responses were observed in dry weight production to elevated Ca concentrations in fertilizer solutions with the highest growth in 4.5 mM treatment. The regression equation was y=2.4026+1.0209x-$0.098x^2$ $(R^2=0.3546^{***})$. However, tissue Ca contents increased lineally as the Ca concentrations in fertilizer solutions were elevated (y=1.2108+0.1333x, $R^2=0.9189^{***}$). In changes of the fresh weight and Ca concentrations in petiole sap, fresh weight production showed quadratic responses to elevated Ca concentrations in fertilizer solution, but Ca concentration increased lineally. The equations in changes of fresh weight and Ca concentrations were y=9.273+4.882x-$0.4245x^2$ $(R^2=0.4935^{***})$ and y=52.311+3.2917x $(R^2=0.6918^{***})$, respectively. When the concentration of calcium at which plant growth was retarded by 10% is regarded as critical concentration level, the calcium contents based on dry weight of above ground plant tissue and in petiole sap should be in the range between 1.6 to 2.25% and 63 to $79mg{\cdot}kg^{-1}$, respectively.

Development of Traffic Volume Estimation System in Main and Branch Roads to Estimate Greenhouse Gas Emissions in Road Transportation Category (도로수송부문 온실가스 배출량 산정을 위한 간선 및 지선도로상의 교통량 추정시스템 개발)

  • Kim, Ki-Dong;Lee, Tae-Jung;Jung, Won-Seok;Kim, Dong-Sool
    • Journal of Korean Society for Atmospheric Environment
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    • v.28 no.3
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    • pp.233-248
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    • 2012
  • The national emission from energy sector accounted for 84.7% of all domestic emissions in 2007. Of the energy-use emissions, the emission from mobile source as one of key categories accounted for 19.4% and further the road transport emission occupied the most dominant portion in the category. The road transport emissions can be estimated on the basis of either the fuel consumed (Tier 1) or the distance travelled by the vehicle types and road types (higher Tiers). The latter approach must be suitable for simultaneously estimating $CO_2$, $CH_4$, and $N_2O$ emissions in local administrative districts. The objective of this study was to estimate 31 municipal GHG emissions from road transportation in Gyeonggi Province, Korea. In 2008, the municipalities were consisted of 2,014 towns expressed as Dong and Ri, the smallest administrative district unit. Since mobile sources are moving across other city and province borders, the emission estimated by fuel sold is in fact impossible to ensure consistency between neighbouring cities and provinces. On the other hand, the emission estimated by distance travelled is also impossible to acquire key activity data such as traffic volume, vehicle type and model, and road type in small towns. To solve the problem, we applied a hierarchical cluster analysis to separate town-by-town road patterns (clusters) based on a priori activity information including traffic volume, population, area, and branch road length obtained from small 151 towns. After identifying 10 road patterns, a rule building expert system was developed by visual basic application (VBA) to assort various unknown road patterns into one of 10 known patterns. The expert system was self-verified with original reference information and then objects in each homogeneous pattern were used to regress traffic volume based on the variables of population, area, and branch road length. The program was then applied to assign all the unknown towns into a known pattern and to automatically estimate traffic volumes by regression equations for each town. Further VKT (vehicle kilometer travelled) for each vehicle type in each town was calculated to be mapped by GIS (geological information system) and road transport emission on the corresponding road section was estimated by multiplying emission factors for each vehicle type. Finally all emissions from local branch roads in Gyeonggi Province could be estimated by summing up emissions from 1,902 towns where road information was registered. As a result of the study, the GHG average emission rate by the branch road transport was 6,101 kilotons of $CO_2$ equivalent per year (kt-$CO_2$ Eq/yr) and the total emissions from both main and branch roads was 24,152 kt-$CO_2$ Eq/yr in Gyeonggi Province. The ratio of branch roads emission to the total was 0.28 in 2008.

Geoacoustic characteristics of Quaternary stratigraphic sequences in the mid-eastern Yellow Sea (황해 중동부 제4기 퇴적층의 지음향 특성)

  • Jin, Jae-Hwa;Jang, Seong-Hyeong;Kim, Seong-Pil;Kim, Hyeon-Tae;Lee, Chi-Won;Chang, Jeong-Hae;Choi, Jin-Hyeok;Ryang, Woo-Heon
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.6 no.2
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    • pp.81-92
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    • 2001
  • According to analyses of high-resolution seismic profiles (air gun, sparker, and SBP) and a deep-drill core(YSDP 105) in the mid-eastern Yellow Sea, stratigraphic and geoacoustic models have been established and seismo-acoustic modeling has been fulfilled using ray tracing of finite element method. Stratigraphic model reflects seismo-, litho-, and chrono-stratigraphic sequences formed under a significant influence of Quaternary glacio-eustatic sea-level fluctuations. Each sequence consists of terrestrial to very-shallow-marine coarse-grained lowstand systems tract and tidal fine-grained transgressive to highstand systems tract. Based on mean grain-size data (121 samples) of the drill core, bulk density and P-wave velocity of depositional units have been inferred and extrapolated down to a depth of the recovery using the Hamilton's regression equations. As goo-acoustic parameters, the 121 pairs of bulk density and P-wave velocity have been averaged on each unit of the stratigraphic model. As a result of computer ray-tracing simulation of the subsurface strata, we have found that there are complex ray paths and many acoustic-shadow zones owing to the presence of irregular layer boundaries and low-velocity layers.

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The Comparison of Existing Synthetic Unit Hydrograph Method in Korea (국내 기존 합성단위도 방법의 비교)

  • Jeong, Seong-Won;Mun, Jang-Won
    • Journal of Korea Water Resources Association
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    • v.34 no.6
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    • pp.659-672
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    • 2001
  • Generally, design flood for a hydraulic structure is estimated using statistical analysis of runoff data. However, due to the lack of runoff data, it is difficult that the statistical method is applied for estimation of design flood. In this case, the synthetic unit hydrograph method is used generally and the models such as NYMO method, Snyder method, SCS method, and HYMO method have been widely used in Korea. In this study, these methods and KICT method, which is developed in year 2000, are compared and analyzed in 10 study areas. Firstly, peak flow and peak time of representative unit hydrograph and synthetic unit hydrograph in study area are compared, and secondly, the shape of unit hydrograph is compared using a root mean square error(RMSE). In Nakayasu method developed in Japan, synthetic unit hydrograph is very different from peak flow, peak time, and the shape of representative unit hydrograph, and KICT method(2000) is superior to others. Also, KICT method(2000) is superior to others in the aspects of using hydrologic and topographical data. Therefore, Nakayasu method is not a proper in hydrological practice. Moreover, it is considered that KICT model is a better method for the estimation of design flood. However, if other model, i.e. SCS method, Nakayasu method, and HYMO method, is used, parameters or regression equations must be adjusted by analysis of real data in Korea.

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Reevaluation of Lane Width Widenings on Horizontal Curve Sections (평면곡선부 확폭량 재설정에 관한 연구)

  • 최재성;백종대
    • Journal of Korean Society of Transportation
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    • v.18 no.4
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    • pp.51-62
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    • 2000
  • The objective of this study was to reevaluate current Korean design values for lane width widenings on horizontal currie sections and to develop a new method for derivation of design values based on low-speed offtracking. For this purpose, earlier research were reviewed and necessary equations were derived. Also, the method for derivation of widening values of Korea was compared with that for other countries. The result showed that present Korean method could not consider the variation of lane widths and design speeds of roads. In this Paper, to solve such problems, the new concept of widening was developed. That is the current concept of widening which concerns only the dimension of vehicles and radius of curves was replaced by a new concept that lane width widenings on horizontal curve sections is the difference between the width required on curries and tangents. The width required on a curve consists of the swept Path of a vehicle, lateral clearance, and additional allowance. The width of a tangent is calculated by multiplying lane width by the number of lanes The result of applying new concept shows that the values derived from new concept are higher than current design values for curries have same radius. This study was based only on low-speed offtracking. Therefor, it is recommended that further studies which consider the superelevation and high-speed effect on offtracking be made to derive more accurate widening values .

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