In this paper, we covered the basic design process of water-cooled cabinets and studied how to determine the target performance of heat exchanger design, which is essential in water-cooled cabinet design. A theoretical method was presented to set the target efficiency of the heat exchanger, and the pressure drop of air passing through the heat exchanger was predicted analytically. A cabinet-level thermal analysis was performed using the target efficiency and pressure drop data of the heat exchanger. The accuracy of the theoretical method was judged by comparing the theoretically predicted operating environment of the internal equipment with the analytically predicted operating environment of the internal equipment.

The effects of pulsed electric field (PEF) treatments on tenderization of beef were investigated. The beef was prepared by using the eye of round. PEF treatment of beef was performed using a newly manufactured movable batch chamber. The PEF treatment was conducted with electric field strength of 0.5~2.0 kV/cm using a fixed pulse width of 30 μs and frequency of 20 Hz. There was no significant change in appearance of PEF treated beef. The cutting force [N] of the sample was greatly reduced as the field strength of the PEF was stronger. The cutting force of beef treated with PEF at 2.0 kV / cm was 41.18 ± 3.28 N and the control was 57.25 ± 4.16 N. In the texture profile analysis, hardness and chewiness weakened as the field strength increased (p <0.05). There was no difference in springiness, cohesiveness, resilience before and after PEF treatment (p <0.05).

Pairs trading is a type of arbitrage investment strategy that buys an underpriced security and simultaneously sells an overpriced security. Since the 1980s, investors have recognized pairs trading as a promising arbitrage strategy that pursues absolute returns rather than relative profits. Thus, individual and institutional traders, as well as hedge fund traders in the financial markets, have an interest in developing a pairs trading strategy. This study proposes pairs trading rules (PTRs) created from a price ratio between securities (i.e., stock index futures) using rough set analysis. The price ratio involves calculating the closing price of one security and dividing it by the closing price of another security and generating Buy or Sell signals according to whether the ratio is increasing or decreasing. In this empirical study, we generate PTRs through rough set analysis applied to various technical indicators derived from the price ratio between KOSPI 200 and S&P 500 index futures. The proposed trading rules for pairs trading indicate high profits in the futures market.

This study was performed to assess the current stock condition of elkhorn sculpin along the Uljin area in the East Sea of Korea. To assess the state of the stock, yield-per-recruit (YPR) and spawning biomass-perrecruit (SBPR) analyses were performed. Estimates of Fmax and F0.1 were 2.10/year and 0.48/year, respectively, and those of F35% and F40% were 0.66/year and 0.54/year, respectively. Current fishing mortality was estimated at 0.63/year and the current age at first capture was 2.41years. F40% was set as the target reference point of the stock. SBPR at F40% and current SBPR were estimated to be 41.85g and 37.77g, respectively. Estimated FOTY which is the fishing mortality for the overfished threshold yield was 0.49/year. The ratio of SBPR/SBPRMSY was calculated as 0.90 and that of F/FOTY was 1.05. The ratio of tc/tc opt was calculated as 1.15 and that of F/FOTY was 1.17. Therefore, the current stock condition of elkhorn sculpin along the Uljin area of Korea has not been overfished, however, it indicates that a light overfishing is going on this stock.

This study attempted to manufacture a Cu-Ga coating layer via the cold spray process and to investigate the applicability of the layer as a sputtering target material. In addition, changes made to the microstructure and prop- erties of the layer due to annealing heat treatment were evaluated, compared, and analyzed. The results showed that coating layers with a thickness of 520 mm could be manufactured via the cold spray process under optimal conditions. With the Cu-Ga coating layer, the α-Cu and Cu3Ga were found to exist inside the layer regardless of annealing heat treatment. The microstructure that was minute and inhomogeneous prior to thermal treatment changed to homogeneous and dense with a more clear division of phases. A sputtering test was actually conducted using the sputtering target Cu- Ga coating layer (~2 mm thickness) that was additionally manufactured via the cold-spray coating process. Consequently, this test result confirmed that the cold sprayed Cu-Ga coating layer may be applied as a sputtering target material.

Saline-tab water (2.5 L) with 0, 2.5, 5, and 10% saline solution contaminated by P. aeroginosa or S. aureus, was electrolyzed with constant electrical current of 2A or 4A for different time durations (1, 2, 4, 8, and 16min). The electrolysis with 2A-4min showed disinfection effect against P. aeroginosa of 105 CFU/㎖ in all saline concentrations. When the electrical current was raised to 4A, P. aeroginosa of 106 CFU/㎖ was disinfected in 4 min. S. aureus of 105 CFU/㎖ was disinfected with 2A-2 min in all saline concentrations. S. aureus of 106 CFU/㎖ was completely disinfected with 2A-8 min. To compare the effect of constant current electrolysis with that of intermittent current electrolysis, solution contaminated with P. aeroginosa of 106 CFU/㎖ was electrolyzed with several pairs of intermittent current of 2A for 2 min followed by 2min pause. Disinfecting effect of intermittent electrolysis was very similar to the constant current electrolysis without pause in 16 min. The present study demonstrated that the direct electrolyzing process with no septum membrane is a convenient and economic sterilization method.

Curcumin (C21H20O6) is a hydrophobic polyphenol found in turmeric. Although curcumin has been used as a natural medicine, its major limitation is related to poor absorption from the gut. Therefore, we developed a method for preparation of Curcumin Nanospheres (CN) to improve the aqueous-phase solubility of curcumin and investigate the functional role of CN in promoting feed efficiency and odor reduction in mice. CN showed inhibitory effects on actate dehydrogenase (LDH) cytotoxicity induced by ecotoxic substance toluene in gut epithelial HCT116 cells. In addition, the weights of internal organs (liver, heart, kidneys, and spleen) and the levels of serum Glutamate Oxaloacetate Transaminase (GOT), Glutamate Pyruvate Transaminase (GPT), and LDH did not show significant differences between mice administered oral CN for two weeks and compared to the control group. Interestingly, CN not only reduced hydrogen sulfide (H2S) and ammonia (NH3) levels and fecal odor, but also improved feed efficiency in mice. These results demonstrate that oral nano-delivery of anti-ecotoxicological CN is a functional system to deliver curcumin to the gut to improve feed efficiency and reduce fecal odor in mice.

As an interpretation of existing jamming effects, the main variables affecting the increase in stiffness due to jamming are known as system density, jamming density, pressure, and particulate temperature. The main variable, jamming density, is closely related to the distribution of particle size and contact properties such as particle shape and friction. However, the complexity of these variables makes it difficult to fully understand the mechanism of the jamming effect. In this paper, we focus on the jamming effects of particles that have more elastic properties than particles such as sand and coffee powder, which are commonly used as constituent particles of existing jamming, in order to reduce complicated factors such as temperature and concentrate on jamming effects based on elastic characteristics of particles. It was experimentally explored the possibility of increasing stiffness by mixing particles of different sizes rather than simply increasing the bending stiffness by controlling the particle size. Through simulations and experiments, we found a case where the stiffness of each particle size distribution is larger than the stiffness of each particle size.

Flavonols as a major kind of plant secondary metabolites are known for health-promoting compounds in onions (Allium cepa L.). The objectives of this study are to determine profiles of flavonol glycosides in different 75 onion accessions. A total of five flavonols (quercetin 3,4'- diglucoside, Q34'diG; quercetin 3-glucoside, Q3G; quercetin 4'-glucoside, Q4'G; isorhamnetin 4'-glucoside, I4'G; quercetin, Q) were identified from onion accessions. In positive ion mode using LC-ESI-MS, individual flavonols were confirmed from one and two glycosylation binding with aglycone such as quercetin and isorhamnetin. Total flavonol contents were distributed in white onion (range of 0.18-6.47 mg/g DW) and purple onion accessions (range of 2.39-6.47 mg/g), respectively. The mean of flavonol contents in purple onion (4.41 mg/g) showed 1.4-fold higher than white onion (3.23 mg/g). The Q34'diG and Q4'G were considered as the major compounds of flavonol glycosides in onion accessions.