• Korean Journal of Radiology
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• 제22권3호
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• pp.435-441
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• 2021

Objective: To evaluate the usefulness of the ventricular volume percentage quantified using three-dimensional (3D) brain computed tomography (CT) data for interpreting serial changes in hydrocephalus. Materials and Methods: Intracranial and ventricular volumes were quantified using the semiautomatic 3D threshold-based segmentation approach for 113 brain CT examinations (age at brain CT examination ≤ 18 years) in 38 patients with hydrocephalus. Changes in ventricular volume percentage were calculated using 75 serial brain CT pairs (time interval 173.6 ± 234.9 days) and compared with the conventional assessment of changes in hydrocephalus (increased, unchanged, or decreased). A cut-off value for the diagnosis of no change in hydrocephalus was calculated using receiver operating characteristic curve analysis. The reproducibility of the volumetric measurements was assessed using the intraclass correlation coefficient on a subset of 20 brain CT examinations. Results: Mean intracranial volume, ventricular volume, and ventricular volume percentage were 1284.6 ± 297.1 cm³, 249.0 ± 150.8 cm³, and 19.9 ± 12.8%, respectively. The volumetric measurements were highly reproducible (intraclass correlation coefficient = 1.0). Serial changes (0.8 ± 0.6%) in ventricular volume percentage in the unchanged group (n = 28) were significantly smaller than those in the increased and decreased groups (6.8 ± 4.3% and 5.6 ± 4.2%, respectively; p = 0.001 and p < 0.001, respectively; n = 11 and n = 36, respectively). The ventricular volume percentage was an excellent parameter for evaluating the degree of hydrocephalus (area under the receiver operating characteristic curve = 0.975; 95% confidence interval, 0.948-1.000; p < 0.001). With a cut-off value of 2.4%, the diagnosis of unchanged hydrocephalus could be made with 83.0% sensitivity and 100.0% specificity. Conclusion: The ventricular volume percentage quantified using 3D brain CT data is useful for interpreting serial changes in hydrocephalus.

• 한국산림과학회지
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• 제9권1호
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• pp.55-60
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• 1969

강원도산(江原道產) 소나무의 성장과정(成長過程)을 파악(把握)하기 위(爲)하여 207본(本)을 벌채(伐採) 수간석해(樹幹析解)하여 재적성장율(材積成長率), 수피율(樹皮率), 직경성장율(直徑成長率)과 재적성장율(材積成長率)과의 관계(關係)등을 조사(調査) 분석(分析)하였는데 그 결과(結果)를 보면 다음과 같다. 1. 재적성장율(材積成長率)은 령급(令級)의 증가(增加)에 따라 점차감소(漸次減少)하며 벌기(伐期)에 도달(到達)할 때는 약(約) 3% 가량(可量)됨을 발견(發見)하였다. 2. 수피율(樹皮率)은 령급(令級)이 커지면 점차감소(漸次減少)하지만 감소율(減少率)은 극(極)히 적어서 그 차(差)가 별(別)로 없음을 발견(發見)하였다. 즉(卽) 령급(令級)에 관계(關係)없이 거의 일정(一定)하리라 생각(生覺)된다. 3. 직경성장율(直徑成長率)은 령급(令級)의 증가(增加)에 따라 점차(漸次) 감소(減少)하는 경향(傾向)은 위와 같으나 유령급(幼令級)에서는 급격(急激)히 감소(減少)하고 노령급(老令級)으로 됨에 따라 감소율(減少率)이 점차(漸次) 적어져서 거의 일정(一定)하게 될 것이라 추측(推測)된다. 4. 직경성장율(直徑成長率)과 재적성장율(材積成長率)의 관계(關係)를 구(求)한 결과(結果) 그 비(比)는 령급(令級)의 증가(增加)에 따라 증가(增加)하지만 증가율(增加率)은 극(極)히 적었음을 보여 준다. 따라서 임분재적성장율(林分材積成長率)을 직경(直徑)의 함수(凾數)로 나타낼 때 그 상관비(相關比)는 일정(一定)하지 않고 증대(增大)한다는 것을 알 수 있다.

• 한국식품영양학회지
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• 제36권6호
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• pp.561-571
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• 2023

The aim of this study was to determine the quality characteristics of bread with 2%, 4%, 6%, and 8% cuttlefish ink added. The pH of the dough decreased as the addition percentage increased, and the addition of 8% was the lowest. The pH of the bread and the fermentation expansion power of the dough decreased as the addition percentage increased. Moisture and ash content were positively correlated with the addition percentage, and the crude protein and crude ash content were negatively correlated. As the addition percentage increased, the color of the bread became darker, and the bread volume decreased. The inside and outside color of the bread also decreased as the addition percentage increased. The volume and specific volume of bread decreased as the addition percentage increased. The amino acid analysis indicated glutamic acid was the largest, free amino acid analysis pointed out aspartic acid the highest. The springiness, cohesiveness, gumminess, brittleness, and hardness of the bread were positively correlated with the addition percentage. Overall, it seems possible to develop bakery items using cuttlefish ink as a functional ingredient.

• 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.

• 한국ITS학회 논문지
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• 제11권2호
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• pp.10-20
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• 2012

본 연구에서는 일반국도 수시조사 지점의 AADT 추정값의 정확도를 높이기 위하여 새로운 그룹핑방법을 제시하였다. 일반적으로 수시조사 자료의 AADT 추정을 위해 월보정계수, 요일보정계수, 조사된 24시간 교통량을 이용하여 AADT를 추정 하므로 상시조사 지점을 그룹핑할 때 상기 세 가지 요인(43개 변수)을 모두 적용하여 그룹핑하였다. 이 방법은 기존의 월보정계수와 요일보정계수만을 이용하여 그룹핑한것과 비교하여 시간대별 교통량을 적용한 것에 있어서 차이가 있다. 그룹핑 결과 5개의 군집이 가장 적당한 것으로 분석되었다. 5개의 군집 중 2개의 군집은 해당되는 지점이 몇 지점 없어 설명하기 어려웠고, 나머지 3개의 군집에서 각각 출퇴근로, 관광부도로, 지방부도로의 특성을 가지는 것으로 나타났다. 각 그룹의 월보정계수 평균과 요일보정계수 평균, 시간대별 교통량 비율의 평균으로 각 그룹의 대표 보정계수를 산출하고, 분석대상지점의 평일 교통량을 해당 그룹의 대표 보정계수를 적용하여 AADT를 추정한 결과 평균적으로 오차가 8.7%인 것으로 나타났다. 이는 기존 연구에서 우수하다고 분석된 동일 대구간 내의 상시조사 보정계수를 적용한 것보다 1.5%오차가 더 적은 것으로 나타났다. 이러한 AADT 산출방법은 전체 수시조사 지점에 적용 가능하므로 실무에서의 활용도가 매우 크다고 판단된다.

• International Journal of Safety
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• 제11권1호
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• pp.19-21
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• 2012

In this thesis, fracture test was performed in order to investigate the fracture strength of SFRC(steel fiber reinforced concrete) structures. The relationship between the compressive force and strain value of SFRC specimens were observed under the compressive strength test. From the fracture test results, the relationship between percentage of fiber by volume, compressive strength, elastic modulus, and tensile strength of SFRC beams were studied, and the measured elastic modulus of SFRC were compared with the calculated elastic modulus by ACI committee 544.

• 콘크리트학회논문집
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• 제17권3호
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• pp.473-480
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• 2005

In this study, a mix design for self compacting concrete was based on Okamura's method and concrete incorporated just a ground granulated blast furnace slag. Replacement ratio of slag is in the range of $20-80\%$ of cement matrix by volume. For the optimal self compactability in mixture incorporating ground granulated blast furnace slag, the paste and mortar tests were first completed. Then the slump flow, elapsed time of 500mm slump flow, V funnel time and filling height by U type box were conducted in concrete. The volume of coarse aggregate in self compacting concrete was in the range of $50-60\%$ to the solid volume percentage of coarse aggregate. Finally, the compressive and splitting tensile strengths were determined in the hardened self compacting concrete incorporating ground granulated blast furnace slag. From the test results, it is desirable for self compacting concrete that the replacement of ground granulated blast furnace slag is in the range of $40-60\%$ of cement matrix by volume and the volume of coarse aggregate to the solid volume percentage of coarse aggregate with a limit of $55\%$.

• 한국자동차공학회논문집
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• 제18권4호
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• pp.62-67
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• 2010

The objective of this experimental study is to verify atomization characteristics of emulsified fuel. The emulsified fuel made of adding the ultrasonic energy is analyzed with atomization characteristics and chemicophysics. As water contents within emulsified fuel and needle angle increase, SMD, viscosity and surface tension were analyzed. By measuring the distribution percentage of hydrogen volume by $^1H$-NMR spectrum, the proportion of aromatics and paraffins is analyzed and compared each other. The results of study is as follows. First, as water contents within emulsified fuel and needle angle of nozzle increases, SMD increases. Second, for the distribution percentage of hydrogen volume, the distribution percentage of aromatics is about 10% and the rest portion is paraffins.

• Asian-Australasian Journal of Animal Sciences
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• 제5권3호
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• pp.439-447
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• 1992

Eight healthy Holstein bulls, 4-6 years old were used to study the effect of season of the year on the biophysical characteristics of semen. Semen was collected twice a week by AV (artificial vagina) over one-year period. The analyses revealed that all the basic seminal traits studied were differed significantly due to season, except the ejaculate volume and consistency and the percentage of swollen spermatozoa in a hypo-osmotic fructose-citrate solution. Ejaculates collected during hot summer season had significantly lower sperm motility, concentration and total counts, and higher percentage of dead spermatozoa than those collected during winter time. Warm spring had moderate semen quality. The temperature-humidity index was calculated and it was associated (p < 0.01) negatively with the ejaculate pH, sperm concentration and total counts, and positively with the % of dead sperms. Ejaculate volume, percentage of swollen spermatozoa, individual motilities did not correlate significantly with the change in temperature-humidity index values. The total live, motile spermatozoa per ejaculate during both the winter and spring seasons showed significant increase of about 37% and 32% respectively over the summer season. Also, rectal temperatures of the bulls were elevated during the hot summer season, while the values of blood hemoglobin and packed-cell volume were decreased.

• 설비공학논문집
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• 제28권8호
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• pp.331-336
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• 2016

This study presents a coolant density calculation device and its corresponding method by using a mass flowmeter and the LabVIEW program. The method can be easily measured with a mixture of coolant and by calculating the percentage of ethylene-glycol without additional investment. The cooling water is very important in a vehicle to protect the engine, and the cooling performance is affected by the mixture concentration and coolant density. The coolant density calculation device measures the mixed concentration in the anti-freeze cooling mixture made from distilled water and ethylene-glycol in real time with the mass flowmeter that is commonly attached to the radiator or heater core. The calculation program for the mixture concentration percentage was developed using the LabVIEW software. The correlation between experimental results and the calculation was conducted for a range of temperature from 40 to $90^{\circ}C$ and by varying the mixture ratio of distilled water and ethylene-glycol. As a result, the anti-freeze coolant concentration in the volume percentage is able to monitor the coolant density in a timely basis by implementing a mixture concentration calculation program without the need for additional equipment investment. The results of the calculation for the mixture concentration level show a maximum 2.7% deviation compared to the experimental results.