Integrating Wildfires Propagation Prediction Into Early Warning of Electrical Transmission Line Outages

Wildfires could pose a significant danger to electrical transmission lines and cause considerable losses to the power grids and residents nearby. Previous studies of preventing wildfire damages to electrical transmission lines mostly analyze wildfire and power system security independently due to their differences in disciplines and cannot satisfy the requirement of the power grid for active and timely responses. In this paper, we have designed an integrated wildfire early warning system framework for power grids, taking prediction of wildfires and early warning of line outage probability together. First, the proposed model simulates the spatiotemporal process of wildfires via a geography cellular automata model and predicts when and where wildfires initially get into the security buffer of an electrical transmission line. It is developed in the context of electrical transmission line operating with various situations of topography, vegetation, wind and, especially, multiple ignition points. Second, we have proposed a line outage model (LOM), based on wildfire prediction and breakdown mechanisms of the air gap, to predict the breakdown probability varying with time and the most vulnerable poles at the holistic line scale. Finally, to illustrate the validation and rationality of our proposed system, a case study for a 500-kV transmission line near Miyi county, China, is presented, and the results under various wildfire situations are studied and compared. By integrating wildfire prediction into the LOM and alarming the holistic line breakdown probability along time, this paper makes a significant contribution in the early warning system to prevent transmission lines to be damaged by wildfires, illustrating the related breakdown mechanisms at the line operation level rather than laboratory experiments only. Meanwhile, the implementation of cellular automata model under comprehensive environmental conditions and simulation of the breakdown probability for the 500-kV transmission line could serve as references for other studies in the community

From carbon nanotubes and silicate layers to graphene platelets for polymer nanocomposites

In spite of extensive studies conducted on carbon nanotubes and silicate layers for their polymer-based nanocomposites, the rise of graphene now provides a more promising candidate due to its exceptionally high mechanical performance and electrical and thermal conductivities. The present study developed a facile approach to fabricate epoxy–graphene nanocomposites by thermally expanding a commercial product followed by ultrasonication and solution-compounding with epoxy, and investigated their morphologies, mechanical properties, electrical conductivity and thermal mechanical behaviour. Graphene platelets (GnPs) of 3.5

C-Terminal Modification on the Immunomodulatory Activity, Antioxidant Activity, and Structure–Activity Relationship of Pulsed Electric Field (PEF)-Treated Pine Nut Peptide

In this study, a novel peptide VNAVL was synthesized by removing the C-terminal histidine on the basis of a bioactive peptide VNAVLH obtained from pine nut (Pinus koraiensis Sieb. et Zucc) protein. The effects of removing histidine on antioxidant activity, immunomodulatory activity, and secondary structure of the PEF-treated peptide were discussed. Compared with VNAVLH, VNAVL only exhibited lower antioxidant activity, but no immunomodulatory activity to release TNF-α, IL-6, and NO by activating RAW 264.7 cells. In addition, both antioxidant and immune activities of VNAVLH were significantly more sensitive to treatment with 40 kV/cm than other field intensities, whereas VNAVL was not sensitive to field strength changes. CD spectra and DSSP analysis verified that both peptides consisted of a β structure and random coil, but the ability of VNAVL to transform the random coil via PEF treatment is weaker than that of VNAVLH. Therefore, PEF treatment might expose the key active site located on the C-terminal histidine by altering the secondary structure of the peptide

Sea cucumber peptides protect against memory impairment by regulating dopamine/serotonin metabolization and synapse plasticity of mice hippocampus

With the increase of social stress and brain aging, memory impairment has become a serious problem. Previous studies have shown preliminary neuroprotective evidence of sea cucumber peptides (SCP) by enhancing behavioral performance and modulating cholinergic system. Here, we further investigated the neuroprotective molecular mechanism of SCP in scopolamine-induced memory impairment mice. Passageway-water-maze and passive-avoidance test revealed that SCP enhanced memory in dose-dependent manner. Therefore, mice hippocampus, derived from high-dose of SCP and Model groups, were analyzed by proteomics. According to the GO functional classification, we further found that SCP increased ACh level, prevent neuronal damage, and improved synapse plasticity. The KEGG pathway enrichment revealed significant up-regulations of dopaminergic/serotonergic synapse and synaptic vesicle cycle, which were validated by key proteins (TH and VMAT2) and downstream mediators (serotonin and dopamine). Overall, this study indicated that SCP protected against memory impairment by improving synapse plasticity and regulating dopamine/serotonin metabolization via TH/VMAT2 pathway

Impact of Climate Change on the Preferred Season for Outdoor Water Activities

The purpose of this study is to predict changes in the season for outdoor water activities due to climate change. Nine public outdoor swimming pools in three megacities of South Korea (Seoul, Daegu, and Busan) were selected as study sites. To determine the preferred weather conditions for outdoor water activities, the preference functions of weather elements for outdoor water activities were structured by finding the best-fitting lines with the Z-score of the number of visitors, which is calculated for each swimming pool each year, and the inflection points or the stabilized point of preference functions are set as thresholds for preferred weather conditions for outdoor water activities. To predict changes in the preferred season for outdoor water activities, future weather data for the 2030s, 2060s, and 2090s derived from RCP (Representative Concentration Pathway) scenarios are adapted to the thresholds of preferred weather conditions. The results of this study show that the preferred temperature range for outdoor water activities is: 24.6 °C to 35.0 °C in Seoul, 25.5 °C to 35.5 °C in Daegu, and 27.4 °C to 34.4 °C in Busan, and that the maximum threshold for precipitation is: 36.5 mm in Seoul, 31.5 mm in Daegu, and 26.5 mm in Busan. The results of this study show that the preferred season for outdoor water activities will expand compared to its current duration due to warmer temperatures in the future, and the preferred period for these activities will shift from June to September to May to June and September to October due to extremely hot weather in July and August beginning in the 2030s. The results of this study imply that there will be major changes in the demand and operation of outdoor water activities due to climate change, making it necessary to begin preparations to combat and respond to climate change

The Effects of Risk Perceptions Related to Particulate Matter on Outdoor Activity Satisfaction in South Korea

In recent years, the Korean public has become aware of the form of air pollution known as particulate matter, with a consequent growth of public anxiety causing a negative risk perception about outdoor activity. This study aims at determining the causal relationship between risk perceptions about particulate matter and outdoor activity satisfaction in South Korea. An Internet survey was conducted with 412 people, and a structural equation model was used to perform confirmatory factor analysis. The statistically significant results show that the perceived risk of particulate matter is higher when people do not show interest in or trust public opinion or policy on the subject. This increases people's perceptions of health risks, which in turn lowers their satisfaction with outdoor activity. Although trust levels in public opinion or policy had a positive impact on outdoor activity satisfaction, this was not statistically significant. These results are expected to contribute to risk communication guidelines in public opinion reporting and to the direction of environmental health policies in developing countries with high levels of air pollution, such as particulate matter.Y

The Effects of Risk Perceptions Related to Particulate Matter on Outdoor Activity Satisfaction in South Korea

In recent years, the Korean public has become aware of the form of air pollution known as particulate matter, with a consequent growth of public anxiety causing a negative risk perception about outdoor activity. This study aims at determining the causal relationship between risk perceptions about particulate matter and outdoor activity satisfaction in South Korea. An Internet survey was conducted with 412 people, and a structural equation model was used to perform confirmatory factor analysis. The statistically significant results show that the perceived risk of particulate matter is higher when people do not show interest in or trust public opinion or policy on the subject. This increases people’s perceptions of health risks, which in turn lowers their satisfaction with outdoor activity. Although trust levels in public opinion or policy had a positive impact on outdoor activity satisfaction, this was not statistically significant. These results are expected to contribute to risk communication guidelines in public opinion reporting and to the direction of environmental health policies in developing countries with high levels of air pollution, such as particulate matter

Healing experiences of middle-aged women through an urban forest therapy program

The aim of this study was to explore and describe the processes of therapeutic effects of the urban forest on middle-aged women by examining their involvement in an urban forest therapy program. The qualitative data used in this study were collected from focus group discussions using semi-structured interviews and analyzed using grounded theory. A core category and four subcategories were created to describe the participants' psychological changes as a result of the therapy program. "Efforts to recognize self-worth" was chosen as the core category. At first, the participants were unfamiliar with their surroundings when they entered the urban forest with strangers. Gradually, participants' attitudes toward their external environment shifted to feelings of comfort and calm owing to an increased awareness of the value of the urban forest. After they acquired knowledge of the forest and experienced emotional bonding with each other, their mental attitudes changed; this allowed them to identify with nature and start reflecting about their own lives. They were then able to develop coping abilities that led to self-healing. The findings of the study illustrated the participants' self-healing processes through interactions with nature, guides, and other group members.OAIID:RECH_ACHV_DSTSH_NO:T201904184RECH_ACHV_FG:RR00200001ADJUST_YN:EMP_ID:A075721CITE_RATE:2.782DEPT_NM:조경·지역시스템공학부EMAIL:[email protected]_YN:YN

The Aroma Fingerprints and Discrimination Analysis of Shiitake Mushrooms from Three Different Drying Conditions by GC-IMS, GC-MS and DSA

The aroma fingerprints and discrimination analysis of shiitake mushrooms under different drying conditions were performed by GC-IMS, GC-MS, and descriptive sensory analysis (DSA) with advanced chemometric methods. Three samples (A, B, and C) were treated with varied drying degree and rate. The sample A and C were at the same drying degree and the sample B and C were at the same drying rate. The GC-IMS volatile fingerprints, including the three-dimensional topographic map, topographic map, and gallery plot, showed that 29 compounds showed higher signal intensities in sample B. Moreover, 28 volatile compounds were identified by HS-SPME-GC-MS and only 8 compounds were ever detected by GC-IMS. The sample B not only had more varieties of volatile compounds, but also showed significant higher contents than sample A and C, especially C8 compounds (p < 0.05). Additionally, sample B showed the highest intensity in mushroom-like, chocolate-like, caramel, sweat, seasoning-like, and cooked potato-like odors by DSA. PCA, fingerprint similarity analysis (FSA) and PLSR further demonstrated that the sample B was different from sample A and C. These results revealed that samples with different drying degree were different and drying degree exerted more influence on the volatile flavor quality than the drying rate. This study will provide a foundation and establish a set of comprehensive and objective methods for further flavor analysis