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Water supply facilities are vulnerable to extreme weather events, such as droughts and floods. To establish a sustainable solution that resists accidents and disasters, a distributed system is required. To supply high-quality tap water using the existing water-supply network, rechlorination facilities must be installed to secure residual chlorine at the pipe end. In this study, a process is developed to determine the injection points and dosages of rechlorination using the latest pressure-driven analysis. The method was compared to the results of demand driven analysis methods. The proposed model was applied to P City in Korea to draw results. A detailed evaluation was performed to study how water pressure head and demand-based hydraulic and water quality analysis results impact the injection points and dosages of rechlorination. Thus, the existing demand-based model shows significant spatial deviations in the pressure head in the presence of water pressure drops, which subsequently lead to over-estimation of chlorine injection dosages for maintaining the concentration of residual chlorine. However, the proposed model involves a numerically validated theory and draws more reasonable results for hydraulic, water quality, and rechlorination dosages. The proposed model can be used as a decision-making tool based on hydraulic analysis for the supply of water of a stable quality.

Background Currently, an in vitro immunogenicity screening system for the immunological assessment of potential porcine reproductive and respiratory syndrome virus (PRRSV) vaccine candidates is highly desired. Thus, in the present study, two genetically divergent PRRSVs were characterized in vitro and in vivo to identify an in vitro system and immunological markers that predict the host immune response. Porcine alveolar macrophages (PAMs) and peripheral blood mononuclear cells (PBMCs) collected from PRRSV-negative pigs were used for in vitro immunological evaluation, and the response of these cells to VR2332c or JA142c were compared with those elicited in pigs challenged with the same viruses. Results Compared with VR2332c or mock infection, JA142c induced increased levels of type I interferons and pro-inflammatory cytokines (TNF-α, IL-1α/β, IL-6, IL-8, and IL-12) in PAMs, and these elevated levels were comparable to the cytokine induction observed in PRRSV-challenged pigs. Furthermore, significantly greater numbers of activated CD4+ T cells, type I helper T cells, cytotoxic T cells and total IFN-γ+ cells were observed in JA142c-challenged pigs than in VR2332c- or mock-challenged pigs. Conclusions Based on these results, the innate immune response patterns (particularly IFN-α, TNF-α and IL-12) to specific PRRSV strains in PAMs might reflect those elicited by the same viruses in pigs.

PURPOSE: The aim of this study was to report homemade glove port technique for single-incision laparoscopic appendectomy (SILA). MATERIALS AND METHODS: Our homemade glove port was composed of a size 6 latex sterile surgical glove, a sterilized plastic bangle, and three pieces of silicon tube (5 cm in length) that were used as the suction tube. Clinical data were retrospectively collected from those patients who underwent SILA at Bucheon St. Mary's Hospital, Bucheon, Gyeonggi-do, South Korea between February 2014 and June 2014, including patient demographics, and operative and postoperative outcomes. To compare the outcomes, a retrospective review was performed for those patients who underwent conventional laparoscopic appendectomy (CLA) between October 2013 and January 2014. Both SILA and CLA were performed by the same surgical team. RESULTS: The SILA and CLA groups included 37 and 57 patients, respectively. The mean age, weight, body mass index (BMI), operation time, and pathologic diagnosis of gangrenous appendicitis were not significantly different between the two groups. However, the mean hospital stay in the CLA group was significantly (P = 0.018) longer than that in the SILA group (4.2 days vs 3.5 days). There was no conversion to open surgery in both the groups. Of the cases who underwent SILA, 10 (27.0%) needed insertion of additional port and drain. There was one (3.2%) complication of umbilical surgical site infection. CONCLUSION: In this study, SILA, with homemade glove port, was technically feasible and safe at low cost.

Porcine reproductive and respiratory syndrome (PRRS) is the most economically important disease to the swine industry, and effective prevention strategy for this disease is still required. Guanylate-binding protein 1 (GBP1) and myxovirus resistance protein 1 (Mx1) are two important proteins belonging to the GTPase superfamily that have been previously described to show antiviral effects. CD163 is considered the most important receptor for PRRSV attachment and internalization. Therefore, the aim of the present study was to evaluate the effects of these genes on host resistance against PRRSV infection in conjunction with the host immune response following PRRSV challenge. The results showed that pigs with AG genotype for the GBP1 exon2 exhibited a significantly higher average daily weight gain (ADWG) and lower average viremia than AA or GG genotype. Furthermore, pigs harbouring the AG genotype for the GBP1 gene presented greater CD4(+)CD25(+) and CD8(+)CD25(+) T cell populations at 4 and 18 days post challenge (dpc), respectively, as compared with other genotypes whereas pigs with CC genotype for the CD163 gene displayed significantly higher nucleocapsid-specific antibody titers at 11dpc. However, pigs with a single 11-bp deletion or insertion in the Mx1 gene did not show significant differences in either weight gain or viremia. Based on these results, we concluded that GBP1 is most significantly associated with resistance against PRRSV infection and efficient T cell activation in pigs.

In order to achieve the required residual chlorine concentration at the end of a water network, the installation of a re-chlorination facility for a high-quality water supply system is necessary. In this study, the optimal re-chlorination facility locations and doses were determined for real water supply systems, which require maintenance in ord3r to ensure proper residual chlorine concentrations at the pipeline under the present and future conditions. The harmony search algorithm (HSA), which is a meta-heuristic optimization technique, was used for the optimization model. This method was applied to two water supply systems in South Korea and was verified through case studies using different numbers of re-chlorination points. The results show that the proposed model can be used as an efficient water quality analysis and decision making tool, which showed the optimal re-chlorination dose and little deviation in the spatial distribution. In addition, the HSA results are superior to those of the genetic algorithm (GA) in terms of the total injection mass with the same number of evaluations.

The railway service in the Seoul metropolitan area is facing variety of l changes such as extension of service coverage, new construction, and introduction of express service which in turn causes changes on demands. The demand affects train operation characteristics (frequency of service, train formation) as well as on the congestion rate which is one of the major evaluation index in metropolitan area user service. For the efficient operation of the train, the relationship among the minimization of fleet number, operating cost, and service level has been analyzed. Using the Powersim, which is a system dynamics (System Dynamics) simulation program for realizing optimized simulation for train-formation, this paper identified that some stations of Gyeong-bu line exceeded limit congestion rate(150%) of a fleet already that means it is best to maintain current condition of the line; however, the Gyeong-in line and the Gwa-chon line showed no excess of the limit congestion rate so that it is possible to reduce 2-4 fleets of train for efficient operation. In addition, in case of Jang-hang line between Cheon-an and Sin-chang, a train consisting of 10 fleets provides services which is same formation of train for Gyeong-bu line. This study proved that the congestion rate will not rise greatly with only 4 fleets of a train for the service in Jang-hang line, and it is considered that a study for shuttle service between Cheon-an and Sin-chang is necessary.

Conventional free sintering of low-temperature co-firing ceramic (LTCC) technology has several merits such as sintering temperature below 1000°C that enables co-firing with electrode materials of silver or copper metal and multilayer structure formation. But due to the free sintering process, large shrinkage occurs. To fabricate electronic devices and components with near zero shrinkage within x, y directions constrained sintering (CS) technology is required. In this study a constrained sintering paste (CSP) utilizing alumina powder, which has a higher sintering temperature than LTCC powders, was fabricated for CS technology. The effect of CSP formulated using alumina powder on shrinkage was studied according to variation in paste composition. As a result ceramic package structure with a cavity was fabricated with shrinkage control of 0.028%, which is far smaller than the current CS technology shrinkage of approximately 0.1%.

For miniaturisation and precision of electronic device, the new technologies such as photoimageable thick film process were combined with conventional thick film process, and constrained sintering with near zero shrinkage in the x and y direction has been proposed. In this research, photoimageable conductive paste for forming embedded components via constrained sintering by low temperature cofired ceramic (LTCC) technology was formulated. Afterwards, by optimising paste formulation, formation process of fine line and sintering method, miniaturised LTCC components especially embedded fine line inductors were fabricated and their properties such as line resolution, surface morphology and yield were investigated. As a result, embedded fine line inductors formed by constrained sintering with fine line resolution of 20 μm and yield over 90% were acquired.

Line width under 100 ㎛ with good resolution is difficult to achieve using conventional thick-film process utilizing screen printing method. However, combined with lithography technology finer line and space for miniaturization and highly integrated package is achievable. In this study, photosensitive Ag paste of optimum formulation used for thick film lithography technology was fabricated by various Ag powder, glass powder and additives. As the result, line width of 30 ㎛ with good definition and reduced mismatch during co-firing with LTCC substrate was acquired. Formulated Ag paste was used to pattern embedded fine line inductor with over 90% yield.

The electrochemical properties of LiNi 0.8 Co 0.2 O 2 coated with ZrO 2 by three different coating processes (ball-milling, sol-gel method, simple grinding) were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), and electrochemical impedance spectroscopy (EIS). Results showed that the ZrO 2 coating significantly improved the capacity retention of the cathode by suppressing the impedance growth at the interface between electrodes and electrolyte and the best cyclability was obtained in the case of employing the simple grinding for the ZrO 2 coating. On the other hand, the initial capacities of the ZrO 2 -coated LiNi 0.8 Co 0.2 O 2 cathode were slightly decreased.

The effect of a ZrO2 coating on the structure and electrochemical properties of the cathode material LiNi0.8Co0.2O2 was investigated using EPMA, TEM, XRD, and electrochemical impedance spectroscopy (EIS). In particular, we focused on the distribution of the ZrO2 on the particle surface to study the relationship between electrochemical properties of the coated cathode and the distribution of the coating materials in the particle. Based on the results from composition analysis and electrochemical tests, it was found that the coating layer consisted of nano-sized ZrO2 particles attached nonuniformly to the particle surface and the ZrO2 layer significantly improved the electrochemical properties of the cathode by suppressing the impedance growth at the interface between the electrodes and the electrolyte.

The effects of gallium doping on the structure and electrochemical properties of LiNi0.8Co0.2O2 were investigated by X-ray diffraction, cyclic voltammetry and charge-discharge tests. LiNi0.8Co0.2−xGaxO2 (x = 0.01, 0.03, 0.05) was synthesized using a sol–gel method and it showed the average particle size less than 1 μm in diameter. Results showed that gallium-doping had no effect on the crystal structure (α-NaFeO2) of the cathode material in the range x ≤ 0.05. On the other hand, two transitions at 3.7–3.9 and 4.2–4.7 V observed during the cycle test were merged into one when the amount of gallium doping increases to 0.05, implying that the enhanced capacity retention with gallium doping is attributed to the suppression of the phase transition of the cathode. However, the increase of gallium content in LiNi0.8Co0.2O2 slightly decreases the initial discharge capacity.