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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a highly transmissible and potentially fatal virus. So far, most comprehensive analyses encompassing clinical and transcriptional manifestation have concentrated on the lungs. Here, we confirmed evident signs of viral infection in the lungs and spleen of SARS-CoV-2-infected K18-hACE2 mice, which replicate the phenotype and infection symptoms in hospitalized humans. Seven days post viral detection in organs, infected mice showed decreased vital signs, leading to death. Bronchopneumonia due to infiltration of leukocytes in the lungs and reduction in the spleen lymphocyte region were observed. Transcriptome profiling implicated the meticulous regulation of distress and recovery from cytokine-mediated immunity by distinct immune cell types in a time-dependent manner. In lungs, the chemokine-driven response to viral invasion was highly elevated at 2 days post infection (dpi). In late infection, diseased lungs, post the innate immune process, showed recovery signs. The spleen established an even more immediate line of defense than the lungs, and the cytokine expression profile dropped at 7 dpi. At 5 dpi, spleen samples diverged into two distinct groups with different transcriptome profile and pathophysiology. Inhibition of consecutive host cell viral entry and massive immunoglobulin production and proteolysis inhibition seemed that one group endeavored to survive, while the other group struggled with developmental regeneration against consistent viral intrusion through the replication cycle. Our results may contribute to improved understanding of the longitudinal response to viral infection and development of potential therapeutics for hospitalized patients affected by SARS-CoV-2.

The importance of conducting necessary studies on grid reliability evaluation has become increasingly important in recent years due to the number of blackout events occurring throughout the world. Additionally, quantitative evaluation of transmission system reliability is very important in a competitive electricity environment. The reason behind this is that successful operation of an electric power company under a deregulated electricity market depends on transmission system reliability management. The results of many case studies for the Korea Electric Power Cooperation (KEPCO) system using the Transmission Reliability Evaluation for Large-Scale Systems (TRELSS) Version 6.2 are illustrated in this paper. The TRELSS was developed by EPRI and Southern Company Services Inc. This paper presents the reliability analysis of KEPCO system expansion planning by using the TRELSS program.

This paper describes an alternative method for grid expansion planning considering construction cost, probabilistic production cost, congestion cost and outage cost of a grid at a composite power system derived from a simulation model. In this paper, a heuristic scenario method is proposed to choose the least cost solution (scenario) among various scenarios cosidering candidate new lines. The characteristics and effectiveness of this simulation model are illustrated by the several case studies on a 21-bus test system.

Reliable operation of power system is fundamental to the on-going industry reform. This paper presents the result of marginal power flow evaluation performed on Korean power system using two commercial software packages: Physical and Operational Margins (POM V. 2.2) and probabilistic reliability assessment (PRA V. 3.1), respectively. The case study of Korea power system for year 2006 data shows that these packages are effective in identifying possible weak points and root causes for likely reliability problems. The potential for these software packages is being explored further for assisting system operators with managing Korea power system under real-life setting in the near future.

The importance and conduct of necessary studies on grid reliability evaluation have become increasingly important in recent years due to the number of blackout events occurring throughout the world. Additionally, quantitative evaluation of transmission system reliability is very important in a competitive electricity environment. The reason is that successful operation of an electric power under a deregulated electricity market depends on transmission system reliability management. This paper suggests that the important input parameters of a probabilistic reliability evaluation tool for the KEPCO-system by sensitivity analysis of high reliability level operation. Simultaneously, it also presents sensitivity analysis probabilistic reliability evaluation of practical KEPCO-system long-term transmission system expansion planning (2006-2010). The tool utilized a Transmission Reliability Evaluation for Large-Scale Systems (TRELSS) which was developed by EPRI and Southern Company Services Inc.

The importance and conducting necessity studies on grid reliability evaluation have been increasingly important in recent years due to the number of black-out events occurring through in the world. Quantity evaluation of transmission system reliability is very important in a competitive electricity environment. The reason is that the successful operation of electric power under a deregulated electricity market depends on transmission system reliability management. Also in Korea it takes places. The results of many case studies for the KEPCO system using the Transmission Reliability Evaluation for Large-Scale Systems (TRELSS) Version 6_2, a program developed by EPRI are introduced in this paper. Some sensitivity analysis has been included in case study. This paper suggests that the some important input parameters of the TRELSS can be determined optimally from this sensitivity analysis for high reliability level operation of a system.

The importance and necessity of conducting studies on grid reliability evaluation have been increasingly important in recent years due to the number of black-out events occurring through in the world. Quantity evaluation of transmission system reliability is very important in a competitive electricity environment. The reason is that the successful operation of electric power under a deregulated electricity market depends on transmission system reliability management. Also in Korea it takes places. This paper presents the probabilistic reliability evaluation for 765KV transmission lines in KEPCO grid expansion planning. The Transmission Reliability Evaluation for Large-Scale Systems (TRELSS) Version 6.2, a software package developed by Electric Power Research Institute (EPRI) is utilized in determining probabilistic reliability evaluation indices of KEPCO-system.

Reliability and power quality have been increasingly important in recent years due to the number of black-out events occurring through in the world. Quantity evaluation of transmission system reliability is very important in a competitive electricity environment. The reason is that the successful operation of electric power under a deregulated electricity market depends on transmission system reliability management. This paper presents sensitivity analysis of probabilistic reliability evaluation of Korea power system in long-term planning (2005-2010) by using the transmission reliability evaluation for large-scale systems (TRELSS) program. The case studies present the probabilistic reliability evaluation indices of practical Korea power system as applied TRELSS which has determined optimally control input parameters with Korea power system.

A goal of deregulation electric market is to impulse strengthening competition of new choices and economic benefits for utilities under constraints such as system reliability, stability, security and quality etc... The objective of operational issues would be to minimize the total system cost while satisfying all associated system constraints for the long-term generation and transmission expansion planning. This paper presents sensitivity analysis of transmission congestion by probabilistic reliability evaluation for KEPCO system. This paper focuses on transmission lines/transformers capacity constraints to be associated system load levels to impact on probabilistic reliability evaluation indices of bulk system. The sensitivity analysis of results is included in case studies. This paper suggests that the important input parameters can be determined optimally from this sensitivity analysis for high reliability level operation of a system. TRELSS program was used for the assessment tool