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The effects of cell parameters on SOFC cell unit performance have been investigated experimentally and numerically. The experiment was conducted using the anode-supported SOFC cell unit (100cm2) and the CFD simulation model was also performed adapting same geometry, material properties, and cell parameters of SOFC cell unit. 3D SOFC cell unit simulation model including electrochemistry, heat and mass transfer, and fluid dynamics are solved by COMSOL Multiphysics. In the experiment, the voltage was measured under fixed current density condition, so current fixed method was used in numerical simulation. Because the simulation results show good agreement with experimental data, the effects of cell parameters on SOFC cell unit performance could be investigated by changing porosity, thickness of electrode and electrolytes using our simulation model. The cell performance was also analyzed by calculating each overpotentials (activation loss, concentration loss, and ohmic loss). With this model, we could find the optimal cell design parameters and we expect that the current findings can provide a guideline for the design of SOFC cell unit.

An unstructured mesh Navier-Stokes solver employing a Maxwell slip boundary condition was developed. The present flow solver was applied to the simulation of flows around an axisymmetric hollow cylinder in a Mach 10.4 freestream, known as Calspan-UB Research Center (CUBRC) Run 14 case, and the velocity slip and the temperature jump on the cylinder surface were investigated. The effect of tangential momentum and thermal accommodation coefficients used in the Maxwell condition was also investigated by adjusting their values. The results show that the reverse flow region is developed on the body surface due to the interaction between the shock and the boundary layer. Also, the shock impingement makes pressure high. The flow properties on the surface agree well with the experimental data, and the velocity slip and the temperature jump vary consistently with the local Knudsen number change. The accommodation coefficients affect the slip phenomena and the size of the flow region. The slip phenomena become larger when both tangential momentum and thermal accommodation coefficients are decreased. However, the range of the reverse flow region decreases when the momentum accommodation coefficient is decreased. The characteristics of the momentum and thermal accommodation coefficients also are overlapped when they are altered together.

Selenium (Se) is an essential element, known to bioaccumulate to toxic levels in aquatic environments. Here, we tested the toxic and physiological stress response of goldfish, Carassius auratus exposed to different concentrations of Se for 120 h. At the end of the experiment, the toxic stress indicators [metallothionein (MT), aminotransferase/aspartate (AspAT and AlaAT), and gill Na+/K+-ATPase] and other stressrelated parameters [corticotropin releasing hormone (CRH), adrenocorticotropic hormone (ACTH), and glucocorticoid receptors (GRs) mRNA and activity and/or plasma ACTH, cortisol, glucose, hydrogen peroxide (H2O2), and muscle lipid peroxidation (LPO)] were significantly higher in specimens exposed to 3 and 4 mg/L of Se than in those exposed to lower concentrations (0 and 2 mg/L). These results indicated that 3 and 4 mg/L Se concentration can induce an acute toxic and physiological stress response in aquarium conditions.

CHF experiments were conducted in subcooled flow boiling region at atmospheric pressure. Magnetite nanoparticles were deposited sufficiently on the test sections in same deposition process. Then, working fluid was changed to DI water. After the nanoparticle deposition process, the surface became very hydrophilic even after CHF experiment using DI water. The wettable surfaces were observed using static contact angle and SEM image. CHF results of bare stainless surface and nanoparticle-deposited surface were obtained in the subcooled boiling region. Experiments were conducted over a mass flux range from 1,000 kg/m2s to 5,000 kg/m2s and with inlet temperatures of 40, 60, and 80 °C. The CHF enhancement was from 0% to 40 % by the nanoparticle deposition, which is related wettability enhancement. The CHF enhancement increased as the mass flux increased, which lead to exit quality decrement.

We investigated the effect of light spectra on circadian rhythm by exogenous prolactin (PRL) using light-emitting diodes (LEDs): red, green and purple. We injected PRL into live fish or treated cultured brain cells with PRL. We measured changes in the expressions of period 2 (Per2), cryptochrome 1 (Cry1), melatonin receptor 1 (MT1) mRNAs, and MT1 proteins, and in the plasma PRL, serotonin and melatonin levels. After PRL injection and exposure to green light, MT1 expression and plasma melatonin levels were significantly lower, but the expressions of Per2 and Cry1 were significantly higher than the others. Plasma serotonin after PRL injection and exposure to red light was significantly lower than others. These results indicate that injection of high concentration PRL inhibits melatonin, and inhibited melatonin regulates circadian rhythm via clock genes and serotonin. Thus, exogenous PRL regulates the circadian rhythm and light spectra influence the effect of PRL in goldfish.

We investigated the effects of light spectra on circadian rhythms under high thermal stress using red, green and purple light-emitting diodes (LEDs). To assess differences in circadian rhythms during high thermal stress under different LED light spectra, we measured changes in the expression of the melatonin receptor 1 (MT1), period 2 (Per2), and cryptochrome 1 (Cry1) genes and MT1 protein, and in the plasma melatonin and glucose levels. Under high water temperatures and red light conditions, MT1 expression and plasma melatonin and glucose were significantly higher than under low water temperatures and other light spectra, but Per2 and Cry1 expressions were significantly lower. Thus, high water temperatures induce oxidative stress and melatonin acts as an antioxidant molecule. Further, melatonin regulates circadian rhythms via clock genes, and green and purple lights may be suitable for maintaining circadian rhythms in goldfish Carassius auratus, as these wavelengths generally penetrate freshwater more ef...

Leptin plays an important role in energy homeostasis and reproductive function in fish, especially in reproduction. Migrating fish, such as salmonoids, are affected by external environmental factors, and salinity changes are a particularly important influence on spawning migrations. The aim of this study was to test whether changes in salinity affect the expression of leptin, estrogen receptors (ERs), and vitellogenin (VTG) in chum salmon (Oncorhynchus keta). The expression and activity of leptin, the expression of ERs and VTG, and the levels of estradiol-17β and cortisol increased after the fish were transferred to FW, demonstrating that changes in salinity stimulate the HPG axis in migrating female chum salmon. These findings reveal details about the role of elevated leptin levels and sex steroid hormones in stimulating sexual maturation and reproduction in response to salinity changes in chum salmon.

The study aimed to test differences in the hormones of the hypothalamus–pituitary–gonad axis, Kisspeptin (Kiss) and sex steroids, and the sexual maturation of goldfish (Carassius auratus) according to various photoperiods: 10 h light (L):14 h dark (D) (short day), 12L:12D (control), and 14L:10D (long day). To investigate the sexual maturation under various photoperiods, quantitative real-time PCR (QPCR) assays for salmon gonadotropin-releasing hormone, chicken gonadotropin-releasing hormone, gonadotropin hormones (GTHs), Kisspeptin 1 (Kiss1), and its receptor, G protein-coupled receptor 54 (GPR54), were developed. mRNA expression was monitored in cultured pituitary cells (in vitro) of various photoperiod groups. Furthermore, we injected or treated the animals with Kiss and found that Kiss treatment increases the mRNA expression levels of GTHs. We measured the plasma follicle-stimulating hormone (FSH), luteinizing hormone (LH), and 17α-hydroxypregnenolone levels. The gonadotropin-releasing hormones (GnRHs)...

Micro patterns are used to maximize the performance and efficiency of the product in many industries such as energy, display, printing, biology, etc. Nowadays, the fabrication technology for micro patterns has been developed in various ways such as photolithography, laser machining, electrical discharge machining and mechanical machining. Recently, mechanical machining the size of smaller than 1 micrometer could be tried, because the technology related to the machining was developed brilliantly. This paper shows the experiments using cutting processes in order to fabricate the micro pattern. Micro patterns of the size of several micrometers were machined by the diamond tools of two different shape, the deformation and generation of burr were investigated.

We investigated the effects of the different light emitting diodes (LEDs; red, green, blue, and mixed purple) on oxidative stress by measuring the expression and activities of antioxidant enzymes, plasma H2O2, lipid peroxidation (LPO), aspartate aminotransferase (AspAT), alanine aminotransferase (AlaAT) levels, and melatonin during thermal stress (low-water temperature, 22 → 14°C; high-water temperature, 22 → 30°C) on goldfish, Carassius auratus. The expression and activity of the antioxidant enzymes and levels of H2O2, LPO, AspAT/AlaAT, and melatonin were significantly higher after the fish were exposed to low-/high-water temperature environments. Furthermore, in green and blue lights, the expression of antioxidant enzymes and mRNA of heat shock protein 70, and the activity of the antioxidant enzymes and plasma H2O2, LPO, and melatonin levels were significantly lower than those under other light spectra. The results indicated that low-/high-water temperature conditions induced oxidative stress in goldfish and green and blue LEDs inhibit oxidative stress.

In this work, machining test was carried out in various machining conditions using ultrasonical vibration capable CNC machine. For work material, alumina ceramic (Al2O3) was used while for tool material diamond electroplated grinding wheel was used. To evaluate ultrasonical vibration effect, grinding test was performed with and without ultrasonic vibration in same machining condition. In ultrasonic mode, ultrasonic vibration of 20kHz was generated by HSK 63 ultrasonic actuator. On the other hand, grinding forces were measured by KISTLER dynamometer. And an optimal sampling rate for grinding force measurement was obtained by a signal processing and frequency analysis. The surface roughness of the ceramic was also measured using stylus type surface roughness instrument and atomic force microscope (AFM). Besides, the scanning electron microscope (SEM) was used for observation of surface integrarity.

The study aimed to test differences in immune ability and clock gene expression between intact fish and ophthalmectomized yellowtail clownfish exposed to light-emitting diodes (LEDs). Clock genes (Period 2, Per2; Cryptochrome 1, Cry1) and melatonin receptor 1 mRNA and protein expression in all wavelengths groups were significantly lower in ophthalmectomized fish than in intact fish, but ophthalmectomized fish exposed to green and blue LEDs showed expression levels similar to intact fish. Furthermore, indicators of immune activity (immunoglobulin M; IgM mRNA and protein expression and lysozyme activity) were significantly higher in ophthalmectomized fish exposed to green and blue LEDs than other groups of ophthalmectomized fish. Also, plasma H2O2 levels in ophthalmectomized fish exposed to green and blue LEDs showed their levels similar to intact fish. These results suggest that short wavelengths affect the daily rhythms of fish and enhance the immune ability, even in the absence of an eye.

Kisspeptins (Kiss) have been recognized as potent regulators of reproduction in teleosts, and Kiss is suggested to be a key regulator of the hypothalamus-pituitary-gonad axis (HPG). However, its regulatory role on reproduction in fish remains unclear. Therefore, to investigate the role of Kiss on fish reproduction, this study aimed to test differences in the hormones of the HPG axis, Kiss as neuropeptides, and sex steroids on the sexual maturation of paired cinnamon clownfish, Amphiprion melanopus, following treatment with Kiss. We investigated the actions of sex maturation hormones, including HPG axis hormones and sex steroid hormones, such as gonadotropin-releasing hormones, gonadotropin hormones (GTHs), GTH receptors, estrogen receptors, and vitellogenin in the pituitary, gonads, and liver following treatment with Kiss. The expression levels of HPG axis genes increased after the Kiss injection. In addition, the levels of plasma 17α-hydroxypregnenolone, estradiol-17β, and 11-ketotestosterone increased. These results support the hypothesis that Kiss play important roles in the regulation of the HPG axis and are most likely involved in gonadal development and sexual maturation in cinnamon clownfish.

In this work, machining test was carried out in various machining conditions using ultrasonic vibration capable CNC machine. For work material, alumina ceramic (Al2O3) was used while for tool material diamond electroplated grinding wheel was used. To evaluate ultrasonic vibration effect, grinding test was performed with and without ultrasonic vibration in same machining condition. In ultrasonic mode, ultrasonic vibration of 20 kHz was generated by HSK 63 ultrasonic actuator. On the other hand, grinding forces were measured by KISTLER dynamometer. And an optimal sampling rate for grinding force measurement was obtained by a signal processing and frequency analysis. The surface roughness of the ceramic was also measured by using stylus type surface roughness instrument and atomic force microscope (AFM). Besides, the scanning electron microscope (SEM) was used for observation of surface integrality.

Since year 2001 to the present time, the aircraft accidents and serious incidents in our country have surpassed 150 occurrences. The Boeing has published the statistical summary of commercial jet airplane accidents annually for the past 10 years on the basis of the occurrence categories defined by the CICTT(CAST/ICAO Common Taxonomy Team), and the number of occurrences is in order of loss of control(LOC-I), controlled flight into terrain(CFIT) and runway excursion (RE). Like the NTSB and the EASA, when fatal and non-fatal accidents are aggregated, though fatality rate is low, abnormal runway contact(ARC), system/component failure(SCF-PP/NP), ground handling(RAMP) rank high in the CICTT occurrence categories. With the less occurrence frequency, it is difficult to statistically analyze the aircraft accidents in our country, thus customarily the accidents and the serious incidents on aggregate are consolidated, and the statistical analysis is performed. This study categorizes the accidents and serious incidents to the domestic transportation aircraft in the past 10 years according to the CICTT occurrence categories, that is compared with foreign practices, and the implications have been discussed. From years 2001 through 2010, the accidents to the domestic transportation aircraft occurred in order of system failure(SCF-NP), ARC and power plant failure(SCF-PP), and when the accidents and the serious incidents are consolidated and analyzed, it is verified that a distribution appears similar to the European accident occurrence categories defined from 300 accident occurrence data.

Selenium (Se) is an essential element that has relevant roles in growth, immunity, and the protection of cell membranes in organisms under normal conditions. The aim of this study was to test the antioxidant and immune functions of goldfish Carassius auratus after Se treatment. At the end of the experiment, levels of antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase) and immune functions (immunoglobulin M protein and plasma lysozyme, thyroxine, and triiodothyronine) were significantly higher in goldfish exposed to 1 and 2 mg/L of Se than those exposed to 0.5 and 3 mg/L doses. In addition, plasma glutathione, H2O2, and lipid peroxidation levels were significantly lower in the 1 and 2 mg/L treatment group than 0.5 and 3 mg/L treatment group. These results indicated that 1 and 2 mg/L of Se enhance antioxidant defense and immune system function under aquarium conditions.

Migrating fish such as salmonids are affected by external environmental factors and salinity changes are particularly important, influencing spawning migration. The aim of this study was to test whether changes in salinity would affect the expression of the hypothalamic-pituitary-gonadal (HPG) axis hormones (gonadotropin-releasing hormones (GnRHs) [salmon GnRH and chicken GnRH-II], GnRH receptors [GnRHR1 and GnRHR5], and mRNA of the gonadotropin hormone [GTH] subunits [GTHα, follicle stimulating hormone β, and luteinizing hormone β]) in chum salmon (Oncorhynchus keta). Fish were progressively transferred from seawater (SW) through 50% SW to freshwater (FW), and the relationship between the osmoregulatory hormone prolactin (PRL) and sexual maturation was determined. The expression and activity of HPG hormones and their receptors, and levels of estradiol-17β and PRL increased after fish were transferred to FW, demonstrating that changes in salinity stimulate the HPG axis and PRL production in migrating chum...

1 한국생산기술연구원 충청권지역본부 (Chungcheong Regional Division, Korea Institute of Industrial Technology)2 한국생산기술연구원 IT융합공정연구그룹 (IT Converged Process R&D Group, Korea Institute of Industrial Technology)3 한국생산기술연구원 미래생산시스템연구그룹 (Future Manufacturing System R&D Group, Korea Institute of Industrial Technology) Corresponding author: youngjae@kitech.re.kr, Tel: +82-31-8040-6165

Ultrasonic vibration can be applied for grinding of difficult to cut materials, such as titanium, ceramics, etc., because the ultrasonic vibration in longitudinal direction can cause reduction of cutting temperature and tool wear. In this paper, a ultrasonic tool horn, which can vibrate longitudinally with a frequency of 20kHz, was designed using finite element method (FEM). And the ultrasonic horn was fabricated for ultrasonic assisted grinding. A grinding test was performed in terms of machining parameters, such as grinding speed, feed rate, etc., in order to study effect of ultrasonic vibration in grinding. The design of experiment (DOE) approach was used for an optimal condition of ultrasonic grinding, which can minimize the grinding forces. The grinding forces were measured and compared between the conventional grinding and ultrasonic assisted grinding. In addition, to characterize the effect of work materials, titanium (Ti6Al4V), FCD700 and S45C were used as work materials. From the experiment, it was found that the grinding forces decreased as the ultrasonic vibration power and the rotation speed of spindle increased while the grinding force was reduced as the feed rate increased. In addition, regression model was formulated for obtaining optimal grinding condition. The ultrasonic vibration provided beneficial effects regardless of work materials, especially for brittle material.

The objective of this investigation was to quantify how thyroid hormone receptors of the sockeye salmon, Oncorhynchus nerka, respond to salinity changes from freshwater (FW) to seawater (SW) conditions. Thy- roid hormone receptors (TRs) mRNA and protein expres- sions levels significantly increased when the fish were transferred from FW to SW, and the plasma T3 and T4 levels were significantly highest at 50 % SW and then maintained as control. Moreover, these parameters were significantly lower in the cortisol-injected groups than in the control. Hence, TRs, T3, and T4 may play a role in SW adaptation, when the fish migrate from FW to SW envi- ronments. We showed a negative correlation between cortisol and thyroid hormone levels, and a significant increase in plasma K ? levels in the kidney when the fish were transferred to SW, with levels being significantly lower in the cortisol-injected group. Hence, cortisol appears to be a stress hormone, and the plasma Na ? and Cl - levels significantly increased when the fish were transferred to SW, with levels being significantly lower in the cortisol- injected group. These results indicate that cortisol modu- lates ion transportation in the plasma.

The paper considers heterogeneous fixed fleet vehicle routing with carbon emission to minimizing the sum of variable operation costs. A cost-benefit assessment of the value of purchasing or selling of carbon emission rights, using a mixed integer-programming model to reflect heterogeneous vehicle routing, is incorporated. Essentially, the use of a carbon market as a means of introducing more flexibility into an environmentally constrained network is considered. Tabu search algorithms are used to obtain solutions within a reasonable amount of computation time. In particular, we show the possibility that the amount of carbon emission can be reduced significantly without sacrificing the cost due to the benefit obtained from carbon trading.

In this paper, HBM DRAM with TSV technique is introduced. This paper covers the general TSV feature and techniques such as TSV architecture, TSV reliability, TSV open / short test, and TSV repair. And HBM DRAM, representative DRAM product using TSV, is widely presented, especially the use and features.

The present study aimed to determine the relationship between melatonin and gonadotropin-inhibitory hormone (GnIH) and their effect on reproduction in cinnamon clownfish, Amphiprion melanopus. Accordingly, we investigated the expression pattern of GnIH, GnIH receptor (GnIH-R), and melatonin receptor (MT-R1) mRNA and protein, as well as the plasma levels of melatonin, during sex change in cinnamon clownfish. We found that GnIH and MT-R1 mRNA and melatonin activity were higher in fish with mature brain than in fish with developing gonads, and using double immunofluorescence staining, we found that both GnIH and MT-R1 proteins were co-expressed in the hypothalamus of cinnamon clownfish. These findings support the hypothesis that melatonin plays an important role in the negative regulation of maturation and GnIH regulation during reproduction.

A 4-axis machine using air guides was developed in order to achieve biconic-Zernike surfaces, one of the F-theta surfaces in this study. A Zernike surface is considered as complete in its optical characteristics; however, its mathematical model is non-linear and complex, resulting in difficulties in generating machining the tool path. This study proposes an approach for generating a tool path for biconic-Zernike surfaces using the normal vector of surface equations under the assumption of a fly-cutter. In order to improve the control accuracy, air guides, instead of mechanical bearings, were designed and installed on linear transfer units. The air guides were designed to maintain an air gap clearance between 4.0μm and 5.0μm. When designing mechanisms on the air guides, uniform pay load distribution was considered to minimize the magnitude of the mechanical momentum. Control accuracy in conventional motion and position error are indicated in case of micro step motion and tracking of the biconic-Zernike surface.

We investigated how different light spectra affect thermal stress in olive flounder (Paralichthys olivaceus), using light emitting diodes (LEDs; blue, 450 nm; green, 530 nm; red, 630 nm) at two intensities (0.3 and 0.5 W/m(2)) at relatively high water temperatures (25 and 30 °C, compared to a control condition of 20 °C). We measured the expression and activity of antioxidant enzymes, superoxide dismutase (SOD) and catalase (CAT), and the levels of plasma hydrogen peroxide (H2O2) and lipid peroxidation (LPO). Furthermore, the levels and mRNA expression of caspase-3 were measured, and terminal transferase dUTP nick end labeling (TUNEL) assays of liver and comet assays were performed. The expression and activity of antioxidant enzymes, as well as plasma H2O2 and LPO levels were significantly higher after exposure to high temperatures, and significantly lower after exposure to green and blue light. Caspase-3 levels and mRNA expression showed a similar pattern. The TUNEL assay showed that apoptosis markedly increased at higher water temperatures, compared with the 20 °C control. In contrast, green light irradiation decreased apoptosis rate. Furthermore, the comet assays showed that nuclear DNA damage was caused by thermal stress, and that green light irradiation played a role in partially preventing this damage. Overall, these results suggest that light with green and blue wavelengths can reduce both high temperature-induced oxidative stress and apoptosis, and that particularly green light is efficient for this. Therefore, green light can play a role in protecting in olive flounder from thermal stress damage.

Because of the expansion of high performance computing (HPC) and server market, demand for HBM DRAM is increasing. With this market flow, diverse customers require various HBM product families. One customer requirement is full bandwidth with less density. Therefore, this work presents a HBM DRAM, which supports 4, 8, and even 2-hi stacks with full-bandwidth performance. The HBM DRAM adopts a peripheral base die architecture, which has smaller chip size and good testability resulting in more manufacturability. This architecture can compensate for process variation, since this problem among core dies within the same known good stacked die (KGSD) is the key issue of TSV-based stacked DRAM [1]. Layout aligning between PHY and TSVs improves the speed performance of the whole system due to reduced data skew. The peripheral base die contains address/command decoders (COMDEC), a core pipe-out (POUT) signal generator, and internal power, references and bias generators. A small-swing technique on a heavy load interface can reduce dynamic power and also has tolerance to process variations.

In this work, grinding test was performed in terms of machining parameters, such as grinding speed, feed rate, etc., in order to study effect of ultrasonic vibration in grinding. The design of experiment (DOE) approach was used for an optimal condition of ultrasonic assisted grinding, which can minimize the grinding forces. In DOE, ultrasonic amplitude power, feed rate, and rotation speed of spindle were chosen as the major machining factors. The grinding forces were measured and compared between the conventional grinding and ultrasonic assisted grinding. From the experiment, it was found that the grinding forces decreased as the ultrasonic vibration power and the rotation speed of spindle increased while the grinding force was reduced as the feed rate increased. In addition, regression model was formulated for obtaining optimal grinding condition.

In this paper, a ultrasonic horn, which can vibrate longitudinally with a frequency of 20㎑, was designed using finite element method (FEM). And the ultrasonic horn was fabricated for ultrasonic assisted grinding. To evaluate machining performance of the fabricated ultrasonic horn, grinding test was conducted on alumina ceramic (Al2O3). In the grinding test, grinding forces was measured and compared between the conventional grinding and the ultrasonic assisted grinding. The results showed that the grinding force in the ultrasonic grinding was lowered than the conventional grindign by 3~20%.

To explore the part of molecular mechanism of rhodopsin family genes in the olive flounder (Paralichths olivaceus), we observed the change patterns of the photoreceptors, rhodopsin (RH) and extra-o...

Ultrasonic machining can be applied for the machining of difficult-to-cut materials using ultrasonical oscillation in an axial direction on top of tool rotation, which can cause reduction of cutting temperature and tool wear. In this study, the experiments were performed on a DMG ULTRASONIC 20 linear machine tool using diamond tools in both conventional and ultrasonic vibration assisted machining. The machining performance was evaluated and compared for both cases in terms of cutting forces, machined surface roughness and tool wear. And the combination technique of 3D surface topography measurement and image processing was applied for the tool wear progress. Overall, the experimental results showed that ultrasonic machining had less tool wear and lower cutting forces at low cutting speed compared to conventional machining. Also surface roughness was slightly lower in ultrasonic machining than that without ultrasonic vibration.

Earned value management(EVM) based progress management was designed to systematically manage large or huge projects with budget based criteria. For this reason, existed methods of EVM based progress management have a practical difficulty to apply to small and medium enterprises(SMEs) not possessing enough human resource, time, and cost. In other words, SMEs have performed simultaneously many small-sized projects emphasizing more project delivery than project budget. This study focuses on the area of project management applying to many small-sized projects simultaneously conducted by SMEs. Thus, the method proposed in this study is to manage only the progress of projects after removing cost factor in order to reduce man powers required for allocating the budget of projects to their all activities in detail in the stage of project planning. This study reveals that SMEs are able to manage progress of many projects easily and intuitively using the proposed method.

We tested the mitigating effects of melatonin injections or irradiation from green-wavelength light-emitting diodes (LEDs) on goldfish (Carassius auratus) exposed to thermal stress (high water temperature, 30 °C). The effects of the two treatments were assessed by measuring the expression and activity levels of the antioxidant enzymes, superoxide dismutase and catalase, plasma hydrogen peroxide, lipid hydroperoxide, and lysozyme. In addition, a comet assay was conducted to confirm that high water temperature damaged nuclear DNA. The expression and activity of the antioxidant enzymes, plasma hydrogen peroxide, and lipid hydroperoxide were significantly higher after exposure to high temperature and were significantly lower in fish that received melatonin or LED light than in those that received no mitigating treatment. Plasma lysozyme was significantly lower after exposure to high temperature and was significantly higher after exposure to melatonin or LED light. The comet assay revealed that thermal stress caused a great deal of damage to nuclear DNA; however, treatment with melatonin or green-wavelength LED light prevented a significant portion of this damage from occurring. These results indicate that, although high temperatures induce oxidative stress and reduce immune system strength in goldfish, both melatonin and green-wavelength LED light inhibit oxidative stress and boost the immune system. LED treatment increased the antioxidant and immune system activity more significantly than did melatonin treatment.

This study was carried out to evaluate the antiobesity effects of Crataegus fructus in 3T3-L1 adipocytes and mice fed a high fat diet (high fat 45% cal). The inhibitory effect of methanol extract from Crataegus fructus on lipid accumulation in 3T3-L1 adipocytes was quantified using Oil red O staining. Compared with the control, lipid accumulation was significantly decreased by 10-25% with treatment with Crataegus fructus extract at a concentration of 600-2,000 ug/ml. Three-week old ICR mice (n

We investigated the effects of a topically applied extract of the heartwood of Broussonetia kazinoki Sieb (B. kazinoki) on atopic dermatitis (AD)-like skin lesions induced by an extract of the house-dust mite Dermatophagoides farina in NC/Nga mice. We found that topically applied B. kazinoki extract suppressed the histological manifestations of AD-like skin lesions, and decreased the levels of plasma immunoglobulin E (IgE) and interleukin-4 (IL-4) in the mice. Moreover, B. kazinoki inhibited the induction of thymus-and-activation-regulated chemokine (TARC/CCL17), macrophage-derived chemokine (MDC/CCL22), and regulated-on-activation-normal T cell-expressed-and-secreted chemokine (RANTES/CCL5) in HaCaT cells activated by tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). In conclusion, our results suggest that B. kazinoki extract has therapeutic advantages in the treatment of AD.

A 75kW class pilot scale MCFC stack composed of 128 unit cells was assembled and operated. 10,000cm2 class MCFC stack components are also developed to fabricate the MCFC stack. The separators with the effective area of 10,000 cm2 were adopted new design concepts such as 3-piece architecture, simple channel structure, and flat mask plate to improve the gas flow behavior and wet seal performance. The electrolyte impregnated anode and cathode with the effective area of 10,000 cm2 were fabricated by the ex-situ process to enhance the reliability of the stack during the heat-treatment. Finally, the gas distribution manifold embedded light-weight stack structure was employed. The stack showed the average open circuit voltage of 1.065V that near meet theoretical one and 78.5kW DC in power output. A 125kW class MCFC stack using the same components will be assembled and started to operate by the end of 2009.

The MCFC matrix has a unique structure in order to maintain homogeneous distribution of molten carbonate melt. It is composed of an electronically insulation material which is stable in molten carbonate melt. Specially, in case of internal-manifold MCFC stack, the sealing on wet-seal side is the most important role and the matrix in internal-manifold stack should be completely flooded by the melt. In this study, we prepared the matrix using nano-sized LiAlO2 powder obtained by ultrasonic spraying heating method. The pore size distribution of the matrix was narrower than that of commercial matrix made of micro-sized powder and the pore size is also smaller than it. The performance of single cell showed that the mean voltage was 0.85 V at 150 mA/cm2 for 600 hours.

In Korea, the research for the development of MCFC stack has been carried out since 1993. The research objective of the ongoing project started in 2004 is the development of 250kW class external reforming type MCFC power generation plant composed of two 125kW class internal-manifold type MCFC sub-stacks. Recently, some remarkable research results including the development of electrolyte impregnated electrodes and 3-piece architecture separators with 7,500cm2 and 10,000cm2 in effective electrode area were achieved. Several 5kw class stack operation tests proved new separators and stack components provided improved stack performances. A 100kW class MCFC stack composed of 130 unit cells with 10,000cm2 in effective electrode area was fabricated to evaluate the new stack concepts. These results will be reflected in the construction and operation of 125 kW class sub-stack and 250 kW class MCFC power generation system.

청주 시내에 위치하고 있는 충북대학교 천문대의 교내 관측소에서 2002년부터 2007년까지 5년간 식쌍성들의 극심시각 결정을 위한 조직적인 CCD 관측이 수행되었다. 그 관측의 부산물로 우리는 2005년부터 2007년까지 CCD 영상 내에 있는 별들의 측광자료를 이용하여 백색광에 대한 1차 대기소광계수들을 결정하였고, 대기소광계수의 계절별, 년도별 변화 특성을 조사하였다. 대기소광계수를 결정하는데 사용한 관측일수는 2005년, 2006년, 그리고 2007년에 각각 57일, 51일, 그리 63일이다. 분석 결과, 2005년, 2006년, 그리고 2007년의 년도별 평균 대기소광계수와 그 표준편차는 대기질량(airmass) 당 각각 $0.^m34{\pm}0.^m18,\;0.^m38{\pm}0^m19$ , 그리고 $0.^m45{\pm}0.^m20$ 으로, 도심에 위치하지 않은 정상적인 천문대에 비해 대기소광계수는 약 2배정도 크며, 표준편차는 약 4배정도 큰 것으로 나타났다. 한편, 대기미세 먼지농도와 대기소광계수를 비교해 본 결과, 대기미세 먼지농도와 대기소광계수가 비슷한 양상으로 변화하고 있어 두 양 사이는 강한 상관관계가 있는 것으로 보인다. 또한, 충북대학교 교내 관측소의 동쪽하늘의 소광계수가 서쪽하늘에 비하여 더 큰 것으로 나타났는데 이는 동쪽 지역이 서쪽 지역보다 더 개발되어 대기소광 공해 물질이 동쪽 하늘에 더 잔존하여 있기 때문으로 설명할 수 있다. 결론적으로 청주 지역 도심 하늘의 대기소광은 매년 $0.^m$ 06/airmass 정도 증가하는 추세에 있다. 이는 현재의 청주 밤하늘이 2배로 밝아지는데에 약 13년 밖에 걸리지 않는다는 것을 의미한다. 이 연구는 대기소광계수의 변화가 한 지역의 공해의 정도를 가르키는 지수로 중요하게 사용될 수 있음을 보여주고 있다. 【Systematic CCD observations of times of minimum lights for eclipsing binaries has been carried out from 2002 to 2007 at Campus Station of Chungbuk National University Observatory which is located in Cheongju city, Korea. As a by-product of our observations, photometric data for stars in CCD images taken from 2005 to 2007 were used to determine 1st order atmospheric extinction coefficient (hereafter AEC) and seasonal and yearly variations of the AECs were studied. Total nights used for determination of AECs were 57 days in 2005, 51 days in 2006, and 63 days in 2007. As a result the annual mean value of the AECs per air mass is calculated as $0.^m34{\pm}0.^m18$ for 2005, $0.^m38{\pm}0.^m19$ for 2006, and $0.^m45{\pm}0.^m20$ for 2007. These values show that the AECs and their standard deviations are two and four times, respectively, larger than those of normal observatories which are not located near large cities. Annual comparison between concentration of atmospheric fine dust and coefficient of atmospheric extinction show strong correlation between two quantities of which time variations show similar patterns. The AECs for the east sky show larger than those for the west sky. It can be easily understood by the reasonable possibility that air pollutants remain more in the east sky than in the west because the east area of Cheongju city has been more developed than the west one. In conclusion the atmospheric extinction of the night sky of Cheongju city has an annual trend of increase of $0.^m06\;airrnass^{-1}\; year^{-1}$ implying that it may take only about 13 years for Cheongju city to have 2 times brighter night sky than the present one. Our study highlights that variations of AEC can be used as an important indicator of air pollution to monitor night skies.】

A 5kW class MCFC short-stack composed of 7 unit cells was fabricated using the separator with the effective electrode area of 7,500cm2, and the electric performances as well as temperature distributions and pressure differences at various operational conditions were observed. To improve its flatness, the separators were designed employing new concepts such as 3-piece architecture, simple channel structure, and flat mask plate. The current density, air and fuel utilization, and gas pressure were selected as the operational parameters for stack operation. The numerical analysis for the stack using in-house made CFD module for MCFC was also carried out. The temperature distributions, pressure differences, and current density distributions of the unit cells were calculated at various fuel utilizations. To evaluate the effectiveness of the CFD model, finally, the results of the stack operation tests were compared with the prediction of numerical analysis.

Utilizing a Simulated Moving Bed (SMB), the conditions for separating bupivacaine enantiomers, a racemic local anesthetic, were determined by triangle theory and simulations using the gPROMS software and the Aspen Chromatography package. The SMB model in this study assumed an axial dispersion flow for the liquid phase and the intraparticle mass transfer was described in terms of a simple Linear Driving Force (LDF) approximation. The parameters (a andb) of the Langmuir Adsorption Isotherm (LAI) were determined using a dynamic method. In the optimal condition the calculated concentrations were confirmed by the experimental results. Values projected by the gPROMS software more closely matched experimental values than those projected by the Aspen Chromatography package.

FIB equipment has the ability to perform etching and chemical vapor deposition simultaneously. It is very advantageously used to fabricate micro structure components having 3D shape because it has a minimum beam size of Φ 10nm and smaller. Currently, FIB technology has been studied the research fields relating to two problems such as low accuracy and low productivity due to redeposition and a charging effect. This paper focuses on applying FIB technology to the field of micro mold fabrication and repair. As such, the simple micro pattern fabrication techniques and the experimental characteristics are studied on FIB-CVD according to ion beam condition and scanning area. We have encountered some remarks that the result of the experiments according to beam current of 8 pA, shows superior CVD yield. But the result of 1318 pA shows the pattern etched off. Furthermore, we also analyzed the scanning area effect for FIB-CVD yield and suggest the maximum yield condition of the chemical vapor deposition for micro part fabrication.

Studies of memory formation have recently concentrated on the possible role of N-methyl- d -aspartate receptors (NRs). We examined changes in the expression of three NRs (NR1, NR2B, and NR2C), olfactory receptor (OR), and adrenocorticotropic hormone (ACTH) in chum salmon Oncorhynchus keta using quantitative polymerase chain reaction (QPCR) during salinity change (seawater → 50% seawater → freshwater). NRs were significantly detected in the diencephalon and telencephalon and OR was significantly detected in the olfactory epithelium. The expression of NRs, OR, and ACTH increased after the transition to freshwater. We also determined that treatment with MK-801, an antagonist of NRs, decreased NRs in telencephalon cells. In addition, a reduction in salinity was associated with increased levels of dopamine, ACTH, and cortisol ( in vivo ). Reductions in salinity evidently caused NRs and OR to increase the expression of cortisol and dopamine. We concluded that memory capacity and olfactory imprinting of salmon is related to the salinity of the environment during the migration to spawning sites. Furthermore, salinity affects the memory/imprinting and olfactory abilities, and cortisol and dopamine is also related with olfactory-related memories during migration.

The adsorption characteristics of a single component and a binary component in the stationary phase using preparative chromatography were investigated with a six-adsorption isotherm model. These analyses were based on the Langmuir model. Each parameter of the adsorption isotherm was obtained with the adsorption raw data that was calculated by frontal analysis (FA). The experimental data and the values calculated using the adsorption isotherm model were compared. The bi-Langmuir model showed good agreement for phenol while the tri-Langmuir model showed good agreement for caffeine. Each characteristic of adsorption was obtained from these results. The effect of competitive adsorption was investigated using the parameters of the adsorption isotherm model with a single component. There was good agreement between the experimental data and the calculated values.

A hybrid approach incorporating a computational fluid dynamics (CFD) package and process simulation tool was employed to simulate the steady-state crystallization of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) in a Y-mixer crystallizer. Mixing effect was intensively investigated through the three-dimensional spatial distributions of velocity, supersaturation, kinetic rates, mean crystal size, coefficient of variation, and yield. The hybrid approach could predict the literature experimental data on mean crystal size, coefficient of variation, and production rate at the exit of the outlet tube reasonably by adjusting three factors (K, Ehet, and f) for nucleation and crystal growth that are difficult to determine by experiment or theory. It was found that even in a small-scale Y-mixer crystallizer a mixing effect was evident and that nuclei were generated dominantly by primary homogeneous nucleation and were grown at the rate controlled by both bulk diffusion and surface integration for the experimental supersaturation range.

A direct and effective approach is presented for the inverse problem of dynamic structural systems, which is related to structural optimization, system identification, and damage detection. The structural modifications are sought for the characteristic changes assigned from the design goals or modal measurements. A finite element method is used for the system analysis and inverse problem. Mathematical programming techniques are applied for the minimization of the deviation of the finite element model from the desired inverse system, along with an objective function of least structural change. The modal method is based on the perturbation equations of a set of selected degrees of freedom and the energy equation associated with the frequency change. The mode shape change is expressed as the sum of the baseline mode shape and complementary vector, which plays a very important role in the search for the inverse solution. The linear perturbation equation is employed to get an initial approximation, which can be improved through iterations with the nonlinear perturbation equation. The proposed method does not involve the system reduction. Therefore, it is believed to be superior to conventional methods, which suffer from the residual error due to transformation of the eigenproblem.

HPLC (High Performance Liquid Chromatography) was utilized for the chiral separation of racemic bupivacaine, and mathematical modeling with competitive Langmuir isotherm was performed to determine the opti- mum feed condition. For each racemic compound, the isotherm parameters a, b and mass transfer coefficients k were obtained by parameter estimation and maximum likelihood method. The agreement of elution profiles between the experimental data and the calculated values was fairly good. In order to find the optimum separation condition, simulations were carried out to determine the feed conditions such as concentration and injection volume. To preparatively separate racemic bupivacaine, the desirable injection volumes were 0.05 ml at 2.0 mg/ml of the con- centration of racemic mixture or 0.01 ml at 20 mg/ml.