• 한국지반신소재학회논문집
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• 제18권4호
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• pp.87-95
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• 2019

토공량 산출은 건설현장에서 최적 공사비 산정을 위한 데이터로 정확한 토공량은 토목 공사의 설계 단계에서 시공단계까지 고려되어야 하는 중요한 요소이다. 토공량 산출을 위해서는 정확한 지형 자료와 정밀한 토공 부피 계산이 필요하다. 본 논문에서는 짧은 시간에 정확한 지형 파악이 가능하고, 경제성 측면에서도 장점을 갖는 드론 측량 기술을 이용하여 고정밀 토공량 산출 시스템을 도출하였다. 시스템의 정확도 검증을 위해 현장 검증시험을 수행하였으며, 드론을 이용한 토공량 산출 결과와 GPS 측량 장비를 이용한 토공량을 비교·분석하였다. 또한, 새롭게 개발한 토공량 부피 계산 알고리즘을 기존 항공사진측량 소프트웨어(Pix4D) 계산 방식과 비교하여 정확도를 검증하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.46-46
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• 2010

In this paper, we studied the volume resistivity and the electrical conductivity properties of nano composites to investigate the electrical properties of epoxy composites added nano MgO. The specimens were produced by classifying to 1.0, 3.0, 5.0, 10[wt%] and virgin specimen according to the addition amount of MgO. We measured the volume resistivity of nano filler using the High Resistance Meter(4329A) at the measuring temperature changed to 25, 50, 80, 100, and [$120^{\circ}C$]. As the result, it is confirmed that the volume resistivity was the highest stability and volume resistivity value is $2.6{\times}10^{17}\;[\Omega{\cdot}cm]$ at 3.0[wt%]. And it is confirmed that the electrical conductivity property is sharply increased at low electric filed region and the conductivity current density is rapidly increased at high electric filed region.

• Bulletin of the Korean Chemical Society
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• 제35권7호
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• pp.2033-2037
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• 2014

A reaction mixture was developed for formation of soft organic monolith that was easily smashed, rinsed, refluxed, filtered, and dried to give monolith particles having high pore volume of macropores. This phase was almost without mesopores. The reaction mixture was composed of methacrylic acid, ethylene glycol dimethacrylate, polyethylene glycol (porogen), and an initiator in a mixed solvent of toluene and isooctane. The selection of porogen and its amount was carefully carried out to obtain the optimized separation efficiency of the resultant phase. The median macropore size was 1.6 ${\mu}m$, and the total pore volume was 3.0-3.4 mL/g. The median particle size (volume based) was 15 ${\mu}m$, and the range of particle size distribution was very broad. Nevertheless the column (1 ${\times}$ 300 mm) packed with this phase showed good separation efficiency (N~10,000-16,000) comparable to that of a commercial column packed with 5 ${\mu}m$ C18 silica particles.

• The Korean Journal of Physiology
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• 제24권2호
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• pp.261-268
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• 1990

It has long been suggested that the cardiac atrium is a low pressure volume receptor controlling body fluid volume and blood pressure. Recently, the cardiac atrium has been found to contain a family of powerful peptides. To clarify the relationship between high blood pressure and the biologically active atrial peptides, experiments were done to define the characteristics of atrial natriuretic peptide secretion in the isolated perfused atria of renal hypertensive rats. Higher concentrations of plasma atrial natriuretic peptide and renin activity were observed in the two-kidney, one clip hypertensive rat compared to the normotensive rat. Atrial volume changes in response to pressure elevations were attenuated in hypertensive rats compared to normotensive rats. Incremental response to atrial volume changes in ANP secretion was accentuated in hypertensive rats. These date suggest that the accentuated atrial natriuretic peptide response to volume changes of hypertensive rats may be a physiological or pathphysiological adaptation to the high blood pressure and may be, at least in part, responsible for the elevated levels of plasma atrial natriuretic peptide observed in hypertensive rats.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2009년 추계학술대회논문집
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• pp.201-210
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• 2009

A volume capturing method using unstructured grid system for numerical analysis of multiphase flows is introduced in the present paper. This method uses an interface capturing method (CICSAM) in a volume of fluid(VOF) scheme for phase interface capturing. The novelty of CICSAM lies in the adaptive combination of high resolution discretization scheme which ensures the preservation of the sharpness and shape of the interface while retaining boundedness of the field, and no explicit interface reconstruction which is perceived to be difficult to implement on unstructured grid system. Several typical test cases for multiphase flows are presented, which are simulated by an in-house solution code(PowerCFD). This code employs an unstructured cell-centered method based on a conservative pressure-based finite-volume method with CICSAM. It is found that the present method simulates efficiently and accurately complex free surface flows such as multiphase flows.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2003년도 Challenges and Achievements in Environmental Health
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• pp.208-212
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• 2003

This study was performed to examine the effects of chaff as bulking materials on temperature, pH, weight and volume reduction and salinity in aerobic composting of food wastes. Volume ratios of food wastes to chaff in reactor Control, Ch-1, Ch-2, Ch-3 and Ch-4 were 4:0, 4:1, 4:2, 4:3 and 4:4, respectively. Reactors were operated for 24 days with 1 hour stirring by 1 rpm and 2 hours aeration per day. The lowering of the volume ratio of food wastes to chaff resulted in the ascending of the highest reaction temperature and the elongation of the high temperature reaction period. The lowering of the volume ratio of food wastes to chaff resulted in the more fast time of pH ascending. The lowering of the volume ratio of food wastes to chaff resulted in the more fast consistency in the weight and volume reduction rates. Salinities were condensed by reaction days. The final salinity of Control was 2.79%, and the final range of salinities of chaff mixtures was 2.18 - 2.37%.

• 한국환경보건학회지
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• 제29권2호
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• pp.56-61
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• 2003

This study was performed to examine the effects of chaff as a bulking material on temperature, pH, weight and volume reduction and salinity in aerobic composting of food wastes. Volume ratios of food wastes to chaff in reactor of Control, Ch-1. Ch-2, Ch-3 and Ch-4 were 4:0, 4:1, 4:2, 4:3 and 4:4. respectively. Reactors were operated for 24 days with 1 hour stirring by 1 rpm and 2 hours aeration per day. The lowering of the volume ratio of food wasted to chaff resulted in the reaction at higher reaction temperature and the elongation of the high temperature reaction period. The lowering of the volume ratio of food wastes to chaff resulted in the more faster pH increase. The lowering of the volume ratio of food wastes to chaff resulted in the more faster reduction in the weight and the volume of wastes. Salinities were condensed by reaction days. The final salinity of Control and the final range of salinities of chaff mixtures were 2.79%, and 2.18~2.37%. respectively.

• 한국수소및신에너지학회논문집
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• 제27권4호
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• pp.349-356
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• 2016

Volumetric capacity metrics at cryogenic condition are critical for technological and commercial development. It must be calculated and reported in a uniform and consistent manner to allow comparisons among different materials. In this paper, we propose a simple and universal protocol for the determination of volumetric capacity of sorbent materials at cryogenic condition. Usually, the sample container volume containing porous sample at RT can be directly determined by a helium expansion test. At cryogenic temperatures, however, this direct helium expansion test results in inaccurate values of the sample container volume for microporous materials due to a significant helium adsorption, resulting significant errors in hydrogen uptake. For reducing this container volume error, therefore, we introduced and applied the indirect method such as 'volume correction using a non-porous material', showing a reliable cold volume correction.

• 대한의용생체공학회:의공학회지
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• 제11권2호
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• pp.195-202
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• 1990

The hypothesis of asymmetric resistance to explain the phenomenon of lung hyperinflation (LHI) during hlgh frequency ventilation (HFV) was quantitatively studied. LHI was predicted by modeling the ism-volume pressure-flow (IVPF) data from 5 human subjects using the empirical Rohrer's equation. Non-steadiness during HFV was compensated by em- ploying recently proposed volume-frequency diagram. Tidal volume and ventilation frequency were 100 ml and 20 Hz, respectively. Airflow pattern was a symmetric sinusoid. The predic- tion results of mean pressure drop across the airways were averaged for those 5 subjects, and compared with zero by one-sided student's t-test. A marginally significant (P<0.1) increase in mean pressure drop was observed during HFV at low lung volumes (below FRC) , which could increase mean lung volume up to one liter When the lung volume was above FRC, no significant LHI (P >0.25) was resulted. LHI seemed to be inversely related to the lung volume. These results recommend to clinically apply HFV only at lung volumes above FRC.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(5)
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• pp.77-80
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• 2001

In this paper, we devised volume pulse detection system which can quantitatively represent a artery elasticity for oriental clinic. Volume pulse wave detecter system consist of transducer which has IRLED-photodiode detecter, temperature sensor and filter and preprocessing circuits, data conversion and serial communication parts, and computer system. The high-pass filter are detect volume pulse wave and lowpass filter detect tissue thickness. The detected volume pulse wave are normalized by tissue thickness value with a division process. As the result of experiment, we can detect normalized volume pulse wave with effectively.