• Journal of Hydrogen and New Energy
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• v.17 no.3
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• pp.286-292
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• 2006

Chlamydomonas reinhardtii is a green algae that can use light energy and water to produce hydrogen under anaerobic condition. This work reports the effect of limiting factors on hydrogen production in sulfur deprived anaerobic C. reinhardtii culture. In order to confirm the relationship between hydrogen production and limiting factors such as residual PSII activity and endogenic substrate degradation, the increase in chlorophyll concentration and the decrease in starch concentration was investigated during sulfur deprivation. The overall hydrogen production increased depending on cell density in range of $0.4{\sim}0.96\;g$ DCW/l. At this time, the increase in chlorophyll concentration during 24 h after sulfur deprivation increased in proportion to hydrogen production, however, the decrease in starch concentration was not proportional to that. Therefore, hydrogen production under sulfur deprivation using green alga was closely associated with the residual PSII activity than the endogenic substrate degradation.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.10a
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• pp.261-264
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• 2002

Interfacial evaluation, damage sensing and cure monitoring of single carbon fiber/thermosetting composite with different curing processes was investigated using electro-micromechanical test. After curing, residual stress was monitored by measurement of electrical resistance (ER) and then it was compared to correlate with various curing processes. In thermal curing, curing shrinkage appeared significantly by matrix shrinkage and residual stress due to the difference in thermal expansion coefficient (TEC). The change in electrical resistance (ΔR) on thermal curing was higher than that on ultraviolet (UV) curing. For thermal curing, apparent modulus was the highest and reaching time until same strain was faster. So far thermal curing shows strong durability on the IFSS after boiling test.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.6 no.1
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• pp.62-70
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• 2007

The development of new materials that are light-weight, yet high in strength has become vital to the machinery, aircraft and auto industries. However, there are a lot of problems with developing such materials that require expensive tools, and a great deal of time and effort. Therefore, the improvement of fatigue strength and fatigue life are mainly focused on by adopting residual stress. The fatigue crack growth rate of the Shot-peened material was lower than that of the Un-peened material. And in stage I, threshold stress intensity factor of the shot-peen processed material is high in critical parts unlike the Un-peened material. Also, fatigue crack growth exponent and number of cycle of the Shot-peened material was higher than that of the Un-peened material. That is concluded from effect of da/dN. And Fatigue life shows more improvement in the Shot-peened material than in the Un-peened material. And compressive residual stress of surface on the Shot-peen processed operate resistance force of fatigue crack propagation.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.2
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• pp.198-207
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• 2008

The conventional Residual Current Protective Devices(RCD, or earth leakage circuit breaker, ELB) operates depending on the total leakage current which is the vector-sum of resistive and capacitive components of a leakage current. However, the electric disaster such as electric shock or fire is mainly caused by the resistive component. Therefore, in this view point, the RCD is more realistic when it operates by the resistive component of the leakage current. In this paper, a new algorithm for measuring the resistive leakage current from the total leakage current is suggested, and is realized to an actual circuit. According to the suggested algorithm, the resistive component of the leakage current can be found by integrating the total leakage current over only a half cycle of the line voltage, and it is realized by using analog switches and resettable integrators. It is confirmed through experiments that the suggested algorithm detects, within maximum average error of 6.74%, the resistive leakage current from the total leakage current, and the RCD employing the suggested algorithm brakes the circuit within the regular interrupt time(30msec).

• Korean Journal of Construction Engineering and Management
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• v.3 no.1 s.9
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• pp.107-114
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• 2002

Recently, a few major construction companies in Korea have a growing interests to the risk management system, and they are trying to apply it to their construction projects. However, the existing methodologies to be applied to the foreign public projects are not proper to the construction environments due to its adaptabilities, that has one time process and heavily depends on personal judgement. The purpose of this paper is to propose a risk response process in consideration of the residual risks, which would be more adaptable and practical in the construction environment, overcoming the current obstacles to be mentioned above. This process has systematic repeat process until the residual risks go down to the risk thresholds based on the efficiency of specific response strategy.

• Journal of the Institute of Convergence Signal Processing
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• v.6 no.3
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• pp.143-147
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• 2005

Monitoring and diagnosis of the operating machines are very important for safety operation and maintenance in the industrial fields. These machines are most rotating machines and the diagnosis of the machines has been researched for long time. We can easily see the faulted signal of the rotating machines from the changes of the signals in frequency. The Linear Predictive Coding(LPC) is introduced for signal analysis in frequency domain. In this paper, we propose fault detection and diagnosis method using the Linear Predictive Coding(LPC) and residual signal energy. We applied our method to the induction motors depending on various status of faulted condition and could obtain good results.

• Transactions of Materials Processing
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• v.18 no.3
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• pp.268-273
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• 2009

Ultraviolet nanoimprint lithography (UV-NIL), which is performed at a low pressure and at room temperature, is known as a low cost method for the fabrication of nano-scale patterns. In the patterning process, maintaining the uniformity of the residual layer is critical as the pattern transfer of features to the substrate must include the timed etch of the residual layer prior to the etching of the transfer layer. In pursuit of a thin and uniform residual layer thickness, the initial volume and the position of each droplet both need to be optimized. However, the monomer mixtures of resin had a tendency to evaporate. The evaporation rate depends on not only time, but also the initial volume of the monomer droplet. In order to decide the initial volume of each droplet, the accurate prediction of evaporation behavior is required. In this study, the theoretical model of the evaporation behavior of resin droplets was developed and compared with the available experimental data in the literature. It is confirmed that the evaporation rate of a droplet is not proportional to the area of its free surface, but to the length of its contact line. Finally, the parameter of the developed theoretical model was calculated by curve fitting to decide the initial volume of resin droplets.

• Korean Journal of Environmental Agriculture
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• v.39 no.2
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• pp.89-94
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• 2020

BACKGROUND: Persistent organic contaminants such as dichlorodiphenyltrichloroethane (DDT) are often found in agricultural soils decades after it was banned in Korea. This study uses hemoglobin and hemoglobin-containing blood meal to reduce the residual DDT in soil. METHODS AND RESULTS: Hemoglobin or blood meal with or without hydrogen peroxide (H₂O₂) was mixed with the DDT-spiked soil prepared for this study, and samples were taken over 14 d-degradation period to measure the residual DDT concentrations. With only hemoglobin, DDT was completely removed after 14 d, while with both hemoglobin and H₂O₂, 73%, on average, removal was observed. Similarly, the blood meal removed 73% of DDT, but with H₂O₂, the DDT removal was only 39%. The lower DDT removal in the presence of H₂O₂ can be attributed to the adverse effects of reactive species. Hemoglobin was more effective than blood meal for DDT removal in a given time; however, with additional blood meal injection, complete DDT removal was achieved. CONCLUSION: Overall, this study shows that the blood meal that is used as a fertilizer can potentially be used to remove residual contaminants such as DDT in agricultural soil.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.5
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• pp.2555-2575
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• 2017

This paper presents a dual exposure fusion method for image enhancement. Images taken with a short exposure time usually contain a sharp structure, but they are dark and are prone to be contaminated by noise. In contrast, long-exposure images are bright and noise-free, but usually suffer from blurring artifacts. Thus, we fuse the dual exposures to generate an enhanced image that is well-exposed, noise-free, and blur-free. To this end, we present a new scale-space patch-match method to find correspondences between the short and long exposures so that proper color components can be combined within a proposed dual non-local (DNL) means framework. We also present a residual filtering method that eliminates the structure component in the estimated noise image in order to obtain a sharper and further enhanced image. To this end, the entropy is utilized to determine the proper size of the filtering window. Experimental results show that our method generates ghost-free, noise-free, and blur-free enhanced images from the short and long exposure pairs for various dynamic scenes.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2000.10a
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• pp.47-53
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• 2000

Saemangeum coastal area is being constructed the 33km sea dike and 40,000ha reclamation area. The purpose of this study is to find the residual circulations in spring before and after the dike construction by a robust diagnostic and prognostic numerical model. Heat flux at the sea surface in May was adopted on the basis of the daily inflow of solar radiation at the earth surface, assuming an average atmospheric transmission and no clouds, as a function of latitude and time of year(George L.P.,J. E. William,1990). The discharge from the Geum, the Mankyung and the Dongjin rivers was adopted on the basis of experience formula of river flow in May(The M. of C.,Korea, 1993). Water temperature and salinity along the open boundaries are obtained from the results of field observations. The results of spring of the residual flow in the Saemangeum coastal area by a prognostic numerical model lead to the following conclusions: Water temperature in spring is the highest, salinity is the lowest and density is the lowest at the upper layer near the coast after the dike construction. The flow pattern at the upper layer during spring is anti-clockwise circulation between Wi and Shinsi islands. The flow pattern at the lower layer is clockwise circulation between Wi and Shinsi islands.