• The Korean Journal of Pesticide Science
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• v.2 no.1
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• pp.1-11
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• 1998

The generally accepted idea for carbohydrate translocation in plants is an osmotic pressure flow hypothesis. According to the hypothesis, a high concentration of carbohydrate in the phloem of carbohydrate synthesis regions (source) causes a water influx into the phloem. The generated osmotic potential in the phloem is responsible for long distance carbohydrate transport through the positive hydrostatic pressure. In regions of carbohydrate utilization and storage (sink), translocated carbohydrates are continuously metabolized and compartmentalized, generating a concentration gradient between source and sinks. In this system, carbohydrates load into the phloem (phloem loading) and unload out of the phloem (phloem unloading). Phloem-mobile herbicides that are applied to plants are also translocated from the source to sinks. However, some experimental results reveal that the patterns of phloem translocation between carbohydrates and herbicides are different. The differences are due, in part, to the physico-chemical properties of herbicides and to the absence/presence of specific carrier(s) in the phloem.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.30-35
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• 2008

This paper describes a fault detection and diagnosis (FDD) system developed for the heat source apparatus in building air-conditioning system. As HVAC&R systems in building become complex and instrumented with highly automated controllers, the processes and systems get more difficult for the operator to understand and detect the mal-functions. Poorly maintained, degraded, and improperly controlled equipment wastes an estimated 15% to 30% of energy used in commercial building. When operating a complex facility, FDD system is beneficial in equipment management to provide the operator with tools which can help in decision making for recovery from a failure of the system. Automated FDD for HVAC&R system has the potential to reduce energy and maintenance costs and improves comfort and reliability. Over the last decade there has been considerable research for developing FDD system for HVAC&R equipment. However, they are being made too much of a theoretical study, so only a small of FDD methods are deployed in the field. This study deduced an actual defect source for the heat source apparatus and suggested a low price FDD method which is ready to be deployed in the field.

• KIEAE Journal
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• v.9 no.1
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• pp.23-30
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• 2009

A lightcourt design is typically used to address issues concerning aesthetics, feeling, and mood. From the view point of environmental aspect, as an ecological shaft space, it plays a key role in controlling inner quality. In particularly, the lightcourt concept allows the exploitation of daylighting by bring natural light into the center of the building, thus eliminating dark deep spaces. Additionally, the lightcourt shades the inner space in summer. The amount of light available at the base of the lightcourt depends on a number of factors; translucency of the top, reflectance and the geometry of the space. In this paper is to exemplify a lightcourt configuration with a sloped wall. It promises the maximized a sense of freedom and daylighting availability. It is a matter of course that the lightcourt with open-top plays a role as a light source for the adjacent space to the lightcourt. A series of lighting simulation provides performance data of daylighting with changing photometric factors. For the case that a skylight is not available, an electric lighting design with metal halide lamps has been established to create luminous ceiling. As expected, a sloped lightcourt with open-top exposes its superiority of daylighting source. Ancillary considerations to enhance of daylighting potential for the adjacent space have been issued with performance data.

• 한국지구물리탐사학회:학술대회논문집
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• 2010.10a
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• pp.155-156
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• 2010

포텐셜 자료의 해석을 위해서는 상하향 연속을 이용하는 경우가 많다. 빠른 계산과 다양한 적용성 때문에 FFT(Fast Fourier Transform)을 이용한 상하향 연속을 주로 사용하는데, FFT를 적용하기 위해서는 격자망 형태로 얻어진 자료가 필요하다. 현장 중자력 자료는 보통 산발적(scattered)으로 얻어지기 때문에 FFT를 수행하기 위하여 격자망 자료로 변환하는 격자화(gridding) 과정에서 계산적인 오차가 발생한다. 반면 등가샘(equivalent source) 방법은 주어진 자료에 맞는 가상의 샘(source)들의 조합을 생성하고, 구해진 샘들의 조합으로부터 임의의 영역에서 필드값을 구하므로 격자화 과정이 필요없다. 이 연구의 목적은 등가샘 방법의 필요성을 보이고 여러 가지 등가샘 알고리즘을 비교분석하고 현장 자료에 사용하기 적합한 등가샘 방법들을 보여주는데 있다. 그림 1에서 보듯이 FFT를 사용한 상향 연속은 FFT 이론상 전 영역에 대한 적분이 필요하나 현장에서는 일부분의 자료만을 획득할 수 있으므로 상향 연속에서 정확한 자력값으로 연속을 수행하는 것은 불가능하다. 그러나 주어진 값들로 등가샘을 구성하여 상향 연속을수행한 결과는 상대적으로 보다 정확한 해에 도달한다. 또한 등가샘 방법을 이용한 연속의 장점은 그림 2와 같이 얻어진 자료의 높이가 서로 다른 자료를 주어진 높이로 연속을수행할 수 있다는 점이다. 또한 한번 등가샘들을 구성하면 이를 이용하여 격자화, 필터링 등을 해석을 위한 기초 자료처리에 적용할 수 있다.

• Journal of Hydrogen and New Energy
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• v.31 no.6
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• pp.637-645
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• 2020

In this paper, entransy analysis is carried out for combined heat and power (CHP) generation system driven by low-grade heat source compared with energy and exergy analyses. The system consists of a regenerative organic rankine cycle (ORC) and an additional process heater in a series circuit. Special attention is paid to the effects of the turbine inlet pressure, source temperature, and the working fluid on the thermodynamic performance of the system. Results showed that the work efficiency of entransy is higher than that of energy but lower than that of exergy, wheress the process heat efficiency of entransy is lower than that of energy but higher than that of exergy. Entrance analysis showed the potential to complement the exergy analysis in the optimal design of the energy system.

• Journal of Hydrogen and New Energy
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• v.32 no.1
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• pp.77-85
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• 2021

In this paper, entransy analysis is carried out for combined heat and power (CHP) generation system driven by low-grade heat source compared with energy and exergy analyses. The system consists of an organic Rankine cycle (ORC) and an additional process heater in a parallel circuit. Special attention is paid to the effects of the source temperature, turbine inlet pressure, and the working fluid on the thermodynamic performance of the system. Results showed that the work efficiency of entransy is higher than that of energy but lower than that of exergy, wheress the process heat efficiency of entransy is lower than that of energy but higher than that of exergy. Entrancy analysis showed the potential to complement the exergy analysis in the optimal design of the energy system.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.2
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• pp.179-189
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• 2006

Ambient gas phase mercury concentrations including elemental mercury ($Hg^0$) were measured at the Potsdam, Stockton, and Sterling sites in NY from 2000 to 2003. Also, concentrations of ambient reactive gaseous mercury (RGM; $Hg^{2+}$) were measured at the Potsdam site during one year. The contribution of RGM($4.2{\pm}6.4pg/m^3$) was about $0.2{\sim}3%$ of the total gas phase mercury concentration measured (TGM: $1.84{\pm}1.24,\;1.83{\pm}0.32,\;3.02{\pm}2.14ng/m^3$ in Potsdam. Stockton, and Sterling, respectively) at the receptor sites. Potential Source Contribution Function (PSCF), a hybrid receptor modeling incorporating backward trajectories was performed to identify source areas of TGM. Using PSCF, southern New York, North Carolina, and eastern Massachusetts were identified as important source areas in the United States, while the copper smelters and waste incinerators located in eastern Quebec and Ontario were determined to be significant sources in Canada. The Atlantic Ocean was suggested to be a possible mercury source. PSCF incorporating back-dispersion and deposition was applied for RGM , as well as PSCF based on 2-days back-trajectories. Two different approaches yielded considerably different results, primarily due to the consideration of dispersion rather than deposition. Using back-trajectory based PSCF, eastern Ohio, southern New York, and southern Pennsylvania where large coal -fired power plants area located were identified as the large sources in US. Metallurgical industry located in eastern Quebec was resolved as well. From the result of back-dispersion and deposition based PSCF, Pennsylvania, mining facilities around Lake Superior, Toronto, Boston, MA, Quebec, and coal power plants in NY were identified to be the significant source areas for Potsdam site.

• Microbiology and Biotechnology Letters
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• v.40 no.4
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• pp.424-429
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• 2012

The intention of this research was to investigate the solubilization of primary sewage sludge using lactic acid bacteria cultured in a glucose and yeast extract medium. Glucose as the carbon source and yeast extract as the source of nitrogen were chosen as an economic medium with the potential for the mass production of lactic acid bacteria. The optimal concentrations of the medium were 3% (w/v) glucose and 2% (w/v) yeast extract. In this study, in order to improve field applications for the solubilization of sludge at sewage treatment plants, a powdered form of lactic acid bacteria was produced. The optimal inoculum of the powder for the maximum efficiency of solubilization was 1% (w/v). In that condition, the SCOD value increased from 8600 (mg/L) at the beginning of experiment to 10290 (mg/L) at 96 h, with the highest solubilization rate (20.6% DDCOD) and 11.2% (SCOD). Also, the TVFAs of the lactic acid bacteria inoculation group were produced more than that of the control group. In particular, acetic acid was produced 5 times more in the experimental group than in the control group. In this research, the potential of lactic acid bacteria in the pretreatment of primary sewage sludge as a solubilizer, and as an energy source producer for microbial fuel cells was revealed.

• Korean Journal of Agricultural Science
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• v.42 no.3
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• pp.207-213
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• 2015

High-quality protein ingredients have been used in nursery diets, in spite of expensive ingredients, to minimize nutritional deficiency and disease problems. Recent dramatic increases in prices of protein products for nursery diets have exacerbated the challenge. Spray-dried egg may be a part of the solutions. Therefore, this review describes the value of spray-dried egg in nursery diets as a high-quality protein source. Spray-dried egg is egg by-product and is produced by only eggs without shell that are below the USDA Grade B standards. Spray-dried egg is an excellent nutrient source: 1) highly digestible, 2) excellent balance of amino acids, 3) rich content of fat, and 4) high metabolizable energy. These can be attributed to growth of nursery pigs. Beyond the provision of bioavailable nutrients, spray-dried egg also may provide specific physiological benefits. Spray-dried egg contains 1) immunoglobulin antibodies (IgY: IgG in egg yolk) that may attach to intestinal pathogens and excrete them and 2) lysozymes antimicrobial protein that can damage bacteria cell wall. Thereby feeding spray-dried egg may reduce concentration of intestinal pathogen and thus improve potential gut health or enteric disease resistance in nursery pigs. This is important for physiologically immature weaned pigs. Based on these benefits, spray-dried egg is believed to have the same benefits as spray-dried plasma protein and milk products in diets for nursery pigs. Therefore, it is suggested that spray-dried egg has a great potential as a valuable protein source in nursery diets.

• Journal of Korean Society on Water Environment
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• v.18 no.4
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• pp.371-377
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• 2002

The purpose of this study is to develop effective operating process in order to achieve more suitable conditions of Anoxic-Oxic-Anoxic-Stripper(AOAS) SBR through real-time control. To improve the removal efficiency, glucose, methanol and synthetic food waste acid fermentant were added as an external carbon source, In the case of glucose and synthetic food waste acid fermentant, TN, TP were removed to average 86.9%, 73.0% respectively. Methanol was removed to average 64.6%, 55.4% respectively. The synthetic food waste acid fermentant proved to be the most efficient and allowed for the substitution of an external carbon source. The removal rate of $COD_{Cr}$, was approximately 90% at all cases. The results of the study that a correlation between ORP (Oxidation-Reduction Potential), pH and DO and nitrification or denitrification when an external carbon source is added and when it isn't was showed that ${\Delta}ORP$ is suitable parameter. ORP reacted properly to denitrification (${\Delta}ORP<-10$) and nitrification (${\Delta}ORP<0$). The use of real-time control saved anywhere between 61 and 67 minutes at the anoxic(1) stage and 26 to 52 minutes at the oxic(1) stage. When the time saved from the anoxic(1) and oxic(1) was added to the anoxic(2) stage for the removal efficiency of TN and TP increased from 0.7 to 13.9% and 12 to 35 % respectively.