• 한국산림과학회지
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• 제3권1호
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• pp.28-31
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• 1963

Recognizing shortcomings and unreasonable points of the usual methods of measurement of the standing-tree volume, author contrived measurement formula of standing-tree volume which is based on stem-curve equation, $y^2=2px$, resulted from the analysises and experiments on stem-curve by differentiation & integration. The results of this study are as follows ; (1) The following is the formula. $V=1/2g_{1.2}$(h+1.2) V=volume of tree $g_{1.2}$ = sectional area at breast heigh h = height of tree (2) So plain is the form of this formula that this formula is more convenient than usual formulas in measuring. (3) The percentage error of this formula is negative and it is remarkably superior to usual formulas except Pressler's formula, in other words, the higher the tree that is measured is, the more inaccurate become pressler's formula, and the percentage error of the breast-height form factor method is direct proportion to the grossness of the tree that is measured, but the higher the tree that is measured, the lower become percentage error of this formula in geometrical progression.

• 디지털산업정보학회논문지
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• 제10권4호
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• pp.29-35
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• 2014

The formula contains up between the text and the structural information, as well as their mathematical symbols. Research on-line or off-line recognition formula is underway actively used in various fields, and various forms of the equation are implemented recognition system. Although many documents are included in the various formulas, it is not easy to enter a formula into the computer. Recognition of the expression is divided into two processes of symbol recognition and structural analysis. After analyzing the location information of each character is specified to recognize the effective area after each symbol, and to the structure analysis based on the proximity between the characters is recognized as an independent single formula. Furthermore, analyzing the relationship between the front and back each time a combination of the position relationship between each symbol, and then to add the symbol which was able to easily update the structure of the entire formula. In this paper, by using a scanner to scan the book formula was used to interpret the meaning of the recognized symbol has a relative size and location information of the expression symbol. An algorithm to remove the formulas for calculation of the number of formula is present at the same time is proposed. Using the proposed algorithms to scan the books in the formula in order to evaluate the performance verification as 100% separation and showed the recognition rate equation.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.908-911
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• 2002

This paper investigates the characteristics of deflection for circular plate that has same supporting condition along the width direction of plate according to the area change of supporting end. For two boundary conditions such as simple supporting and clamping on both ends, this study derives maximum deflection formula of circular plate using differential equation of elastic curve, assuming that a circular plate is a beam with different widths along the longitudinal direction. The deflection formula of circular plate is verified by carrying out finite element analysis with regard to the ratio of length of supporting part to radius of circular plate.

• 한국세라믹학회지
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• 제53권5호
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• pp.535-540
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• 2016

Effects of compositions and sintering conditions on glaze properties are shown in the diagram constructed by using the unity molecular formula (UMF) method in this study. Glossy characteristics of glaze were clearly differentiated by compositional area in the diagram and sintering process. As alumina and silica contents were increased, texture of the glaze became rough and opaque, akin to having been devitrified or underfired. The correlation between glossiness and surface roughness was found to be non-linear and inversely proportionate. Crystalline phases formed in the glaze were also influenced by the compositional area. Due to the high concentration of CaO, anorthite and wollastonite were formed depending on the compositions. Hardness was increased with an increase of alumina and silica concentrations in the glaze.

• 한국조경학회지
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• 제21권2호
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• pp.1-7
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• 1993

This study suggests one hypothesis: The strength between the catchment foreces of urban community parks can be represented to a gravity model. The gravity model is derived from the related of two subjects, witch is related with their distance. A grvity model for the catchments between parks is represented as followed formula: Iij=${\alpha}$${\times}$ $\frac{Pi$.$Pj}{${\beta}$r}$(formula) Here, Iij is a total number of the vistors of park i and j in a year. Pi is population of the catchment area of park i. Pj is population of the catchment area of park j. ${\alpha}$and, ${\beta}$ are parameters. This formula is testified in the case of Chong-ju community parks.

• 한국환경과학회지
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• 제23권11호
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• pp.1775-1790
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• 2014

The regional rainfall intensity formula for Gimhae in Gyeongsangnam-do province is developed in this study. The nine points of rainfall observations were selected. In order to demonstrate the accuracy and the versatility of the proposed rainfall intensity formula, three regions under the jurisdiction of the Meteorological Agency near Gimhae, namely Busan, Changwon, Miryang observatories were selected. The present formula can be effectively employed for various design of hydraulic structures in Gimhae area since it is divided into several refined regions.

• 산업기술연구
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• 제29권A호
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• pp.67-75
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• 2009

In this study, the investigation of hydraulic characteristics and the pier data for the rivers in Youngseo area of Gangwon Province was carried out and the evaluation and comparison between the values from existing formulas and the values from the model tests was conducted, along with the statistical sensitivity analysis of the elements influencing the scour. As a result, the deviation between the values calculated from the existing formulas and the model tests appeared to be 1.09%~63.98% as the piers were getting larger, which indicated that the existing formulas were not appropriate to estimate the scour in the rivers in Gangwon area. And the formula which estimates the scour with the size of the pier only, among the existing ones, was far behind in estimating the sensitivity because of insufficient incorporation of the hydraulic characteristics, though it is convenient to estimate the value. The sensitivity analysis of the value from the model tests and the depth of the scour proved the significant impact on scour by the size of the pier and water depth, indicating 64% and 36%, respectively. In this study, the formula developed through the regression analysis performed based on the values from the model tests, which appeared to be appropriate for the rivers in Gangwon Province, was proposed.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2018년도 학술발표회
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• pp.146-146
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• 2018

Basin evapotranspiration is the result of water balance and energy balance, which is affected by climate and underlying surface characteristics, the process is complex, and spatial and temporal variability is large, the evapotranspiration estimation of river basin is an important but difficult problem in the field of hydrology, over the years, many scholars devoted to the basin actual evapotranspiration estimation and achieved excellent results. We discuss Budyko coupled water-energy balance theory and evaporation paradox, then use the Fu's equation to estimate actual evapotranspiration yearly in different areas with different dryness. The result shows that Fu's equation has high precision for estimating evapotranspiration yearly in our selected study area, and the estimation result has higher precision in the area with high dryness. Then, we propose an improved formula which can be used to estimate actual evapotranspiration monthly. Furthermore, we found that the parameter in the formula reflects general conditions of underlying surface and it is affected by several factors, at last, we tried to propose the calculation formula. The study indicates that Fu's equation provides a reliable method for evapotranspiration estimation in dry regions as well as semi-humid and semi-arid regions, which has great significance for forecasting river basin water resources and inquiring into ecological water requirement.

• International Journal of Naval Architecture and Ocean Engineering
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• 제10권2호
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• pp.141-152
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• 2018

The heating process such as line heating, triangular heating and so on is widely used in plate forming of shell plates found in bow and stern area of outer shell in a ship. Local shrinkage during heating process is main physical phenomenon used in plate forming process. As it is well appreciated, the heated plate undergoes the change in material and mechanical properties around heated area due to the harsh thermal process. It is, therefore, important to investigate the changes of physical and mechanical properties due to heating process in order to use them plate the design stage of shell plates. This study is concerned with the development of formula of plastic hardening constitutive equation for steel plate on which line heating is applied. In this study the stress correction formula for the heated plate has been developed based on the numerical simulation of tension test with varying plate thickness and heating speed through the regression analysis of multiple variable case. It has been seen the developed formula shows very good agreement with results of numerical simulation. This paper ends with usefulness of the present formula in examining the structural characteristic of ship's hull.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.175-180
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• 2007

This paper presents a case study on blasting vibration reduction in NATM(New Australian Tunnelling Method) tunnel construction carried out under a congested residential area. In NATM tunnel constructions, blasting is an essential process, thus vibration phenomenon is inevitable. Therefore, the vibration reduction was tried to avoid expected complaints from the public living in the area. Test blastings were performed to get the constants for an estimation formula of vibration velocity. Then the influence area was approximated using the estimation formula, and construction methods for the vibration reduction were sought based on the results.