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Ethnopharmacological relevance The modified gamgil-tang (GGX) is a mixture of four herbal medicine including Platycodi Radix, Glycyrrhizae Radix, Lonicerae Flos and Mori Radicis Cortex which has been traditionally used to treat lung and airway diseases to relieve symptoms like sore throat, cough, and sputum in Korea. Its major component chlorogenic acid had been reported to have antioxidant, antibacterial, hepatoprotective, cardioprotective, anti-inflammatory, antiviral, and anti-microbial activity. Aim of the study To identify the inhibitory effect of GGX in a particulate matter (PM) induced lung injury mouse model. Materials and methods We evaluated NO production, the release of TNF-α and IFN-γ in PM-induced MH-S cells, and the number of neutrophils, immune cell subtypes, and the secretion of TNF-α, IL-17, CXCL-1, MIP-2 in the PM-stimulated mouse model to assess the inhibitory effect of GGX against PM. In addition, as exposure to PM increases respiratory symptoms, typically cough and sputum, we attempted to evaluate the antitussive and expectorant activities of GGX. Results Our study provided evidence that GGX has inhibitory effects in PM-induced lung injury by inhibiting the increase in neutrophil and inflammatory mediators, deactivating T cells, and ameliorating lung tissue damage. Notably, GGX reduced PM-induced neutrophilic inflammation by attenuating the number of neutrophils and regulating the secretion of neutrophil-related cytokines and chemokines, such as TNF-α, IL-17, MIP2, and CXCL-1. In addition, GGX demonstrated an antitussive activity by significantly reducing citric acid-induced cough frequency and delaying the latent period and expectorant activities by the increased phenol red secretion compared to the control group. Conclusions GGX is expected to be an effective herbal remedy to prevent PM-induced respiratory disease.

An Organic Rankine Cycle (ORC) has a variety of environmental and operating conditions, which result in different efficiency and net work of cycle. In this regard, it is important to determine the optimal operating conditions with the consideration of various operating variables since the outcomes of the low-grade waste heat recovery systems are low as well as highly dependent on the conditions. In this study, the ORC having seawater as a heat source and LNG cold energy as a heat sink is analyzed with cycle parameters as well as the environmental conditions such as seawater temperature. An ORC Economic evaluation Code (OEC) is developed to consider the effects of numerous parameters such as the pump outlet pressure, mass flow rate, pinch point, materials of the heat exchangers, the type of working fluid, cycle configuration, and seawater temperature simultaneously. Based on the analysis, an economic assessment is conducted, so we could find the optimal conditions for the designed ORC systems. Also, it is found that the seawater temperature variation could affect about 23.8% in terms of net work compared to fixed heat source temperature conditions.

In nuclear power plants (NPPs), one of the important yet uncertain phenomena during a station blackout (SBO) accident is the possibility for a counter-current natural circulation flow in the reactor coolant system (RCS) pressure boundary, which could divert the core melt progression and/or the in-vessel fission product (FP) distribution and, in turn, lead to a heatup and eventual creep rupture. From the risk and accident management points of view, one of key concerns is to predict more explicitly whether such a creep rupture can occur in the RCS pressure boundary, and if it indeed can, also predict the most probable time and the most likely location. This paper presents plant-specific analysis results on the potential characteristics of natural circulation-induced creep rupture of the RCS pressure boundary that could potentially take place during an SBO accident of a reference pressurized water reactor (APR1400). MELCOR-CFD (Computational Fluid Dynamics) coupled analysis was performed to determine more precisely the relevant physical parameter that could greatly influence on the behaviour of natural circulation and the ensuing creep rupture. Multiple sensitivity analyses were also carried out to investigate the influence that particular MELCOR modeling schemes and plant conditions have in estimating the RCS creep rupture characteristics. The analysis results and relevant insights were summarized in terms of particular points of interest.

A steam generator tube rupture (SGTR) is a type of containment bypass accidents that if core damage is not prevented during this accident progression, has the potential to lead to a significant release of fission products (FPs) to the environment through the faulted steam generator (SG) or other possible paths in the secondary system. This paper presents a best practice modeling approach to more realistically quantify the FP source terms expected during an SGTR accident of a reference pressurized water reactor (PWR) plant, and also investigates the impact of dedicated accident mitigation actions on the results of interest through the established modeling approach. To consider the integral responses of the reactor, SGs, and containment to a severe accident initiated by SGTR, detailed modeling was performed for a broad spectrum of plant safety/mitigation systems and relevant phenomena influencing the evolution of the accident. As the modeling and simulation tools for the SGTR accident analysis, MELCOR 2.2 and MAAP5 were employed to compare the results of interest. The results of the analysis demonstrate that the release of FPs into the environment could be estimated more realistically as a result of the best practice modeling for the SGTR accident and also it could be greatly decreased through dedicated mitigation actions. Relevant insights are summarized in terms of particular points of interest and remaining uncertainty issues for further study.

An interfacing systems loss of coolant accident (ISLOCA) is a type of containment bypass accident that may lead to a significant release of fission products (FPs) to the environment. This paper presents a best practice modeling approach to more realistically quantify the FP source terms expected during the ISLOCA of a reference pressurized water reactor (PWR) plant and investigates the influence of a dedicated accident mitigation action on the results of interest through the established modeling approach. In addition to this, the key plant features and phenomenological mechanisms that might have a significant influence on the magnitude and timing of FP releases to the environment during an ISLOCA were examined through a couple of sensitivity analyses. To consider the integral responses of the reactor, containment, and auxiliary building to a severe accident initiated by an ISLOCA, detailed modeling was performed for a broad spectrum of relevant phenomena, plant systems, and structures that promote the deposition and retention of FPs along the flow path to the environment. As the modeling and simulation tools for the ISLOCA analysis, MELCOR 2.2 and MAAP5.04 were employed to compare the results of interest. The results of the analysis shows that the present best practice modeling approach proposed here has the potential to significantly decrease the release of FPs into the environment in the event of an ISLOCA. Relevant insights are summarized in terms of particular points of interest and remaining uncertainty issues for further study.

This paper presents a new systematic approach to find a global solution to economic dispatch (ED) with multiple fuel units using a function merger (FM). Currently, no systematic approach has been developed to find a global solution to economic dispatch with multiple fuel units. Various heuristic methods have been proposed, however it is almost impossible to guarantee a global solution by those methods yet. The proposed method uses the FM and λ-P functions. A FM merges several fuel cost functions into one that satisfies the optimal conditions of an ED. The FM procedures are described in detail with illustrative examples. The global optimality of the proposed method is checked with the ACM (All-Combination Method). The proposed method is tested with a 10-generator system. The results show that the global optimality is achievable by the proposed method.

The quench characteristics of high- T C superconducting (HTSC) elements in the integrated three-phase flux-lock type superconducting fault current limiter (SFCL), which consisted of HTSC elements and a three-phase flux-lock reactor wound on one iron core with the same turn’s ratio between coil 1 and coil 2 in each single phase, were investigated. In a normal condition, the magnetic flux generated in the iron core is zero because the magnetic flux generated between two coils of each single phase is canceled out. However, unlike other three-phase SFCL with three isolated iron cores, the integrated three-phase flux-lock type SFCL showed the different fault current limiting characteristics for the three-phase faults such as the single line-to-ground fault, the double line-to-ground fault, the line-to-line fault and the triple line-to-ground fault. In addition, the power burden of HTSC elements comprising the integrated three-phase flux-lock type SFCL can be decreased. In this paper, we investigated the quench characteristics of HTSC elements in the integrated three-phase flux-lock type SFCL according to three-phase ground fault types. Through the experiments for the fault current limiting characteristics of this type SFCL according to three-phase ground fault types, the quench characteristics of HTSC elements were analyzed and compared with those of three-phase resistive type SFCL.