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This article proposes stochastic exploration algorithms for mobile robot exploration problems. Navigation with uncertain conditions in the absence of initial parameters is a situation wherein precomputation and prediction are impossible for a robot. Therefore, stochastic optimization techniques were applied to find the optimal solution for the robot exploration problem. Driving to the unknown areas, the robot updates the frontier line of sensor visibility during the exploration mission. The points of the frontier line are assumed as the swarm population with their own positions and costs, which allows the computation of the next global waypoint. The calculation of global waypoints is carried out by a nature-inspired optimization algorithm that can place a waypoint in uncertainties. This study offers to apply three metaheuristic algorithms individually, such as Whale Optimization, Grey Wolf Optimizer, and Particle Swarm Optimization algorithms, for comparison and testing their performances in the mobile robotics. At first, the simulations based on the proposed exploration algorithms were implemented and evaluated in a created environment. The results were compared in a single and average cases. Then, the real-world experiments using Grey Wolf Optimizer exploration algorithm were conducted in the different types of environments using MATLAB-ROS integration tool. These results proved the effectiveness and applicability of the bio-inspired optimization algorithm in the mobile robotics.

The liquid crystal display (LCD) industry has undergone drastic growth over the past decade. Considering that the lifetime of an LCD device is approximately ten years, a huge end LCD waste glass (ELWG) is being produced from end-of-life LCD devices. The recycling of ELWG derived from LCD device produced before 2011 is limited by the presence of toxic components such as As, Sb and Ba. In this work, the potential of recycling ELWG was examined to be used in the glass wool industry. 17 glass batches using four different simulated ELWGs (mixtures corresponding to LCD glasses produced in 2006, 2008, 2009, and 2010) were prepared and melted. ELWG was introduced up to 20% of the total glass. Two fixed viscosity points (Tm, Tw) corresponding to 102 and 103 dPas, and the liquidus temperature (TL) were determined in the melt state, and leaching tests of the glass powder in an acidic solution based on the toxicity characteristic leaching procedure (TCLP) were also carried out. As the ELWG content was increased, the Tm, Tw, and TL values did not show a linear relationship with the ELWG content, but some fluctuation in the values was observed. The Tm value showed a larger deviation of 28–36 °C from that of the original glass than the Tw (6–14 °C) and TL (2–16 °C) values. As and Sb were not detected in the leaching tests, and the Ba concentration (1.232–2.279 mg/L) was much lower than the TCLP regulatory level (100 mg/L). The observed TW-TL values suggested that the replacement of 20% or more of the total glass by ELWG is possible. Additionally, the economic and environmental effects of the recycling process were discussed.

Environmental crisis challenges human race harder than ever before. Ecologists have produced a massive amount of data to cope with the crisis. Accordingly, so many ecological data platforms have been developed worldwide to manage and analyze these datasets. However, in Korea, ecological datasets produced by different research institutes for different purposes have not been integrated or serviced due to the lack of a well-designed information infrastructure. To address this obstacle, we present EcoBank (www.nie-ecobank.kr), an open, web-based ecological data platform designed to play an important role in ecological informatics in Korea. The architecture of EcoBank comprises core technologies of WebGIS, Application Programming Interface (API), responsive web, and open-source software (OSS). EcoBank has three conceptual modules: data management, analysis, and service. Diverse stakeholders of EcoBank can be classified into three groups: researchers, policymakers, and public users. EcoBank aims to expand its horizons through mutual communication between these stakeholders. As a part of the progress, EcoBank began to broaden its network by linking to other data platforms and repositories over the globe to find possible solutions to ecological issues in Korea.

Over the last three decades many studies have reported the investigation of the redox behaviour of multivalent elements (M) in glass melts by voltammetry. In these works the redox ratio at any temperature, described as ([Mx+]/[M(x+n)+]) or the concentration %[Mx+], was determined under the assumption that the melt was equilibrated with air (PO2 = 0.21 bar). Some potentiometric studies have reported the determination of PO2 in glass melts, however no significant attempts have been made to determine the actual redox ratio using a measured PO2 combined with a corresponding voltammogram. Herein, potentiometry and square wave voltammetry of alkali-lean alumino-borosilicate E-model glass melts doped with Sn were performed sequentially at the same equilibrium state. The actual redox ratios of the main pair, [Sn2+]/[Sn4+], derived from the peak potential and oxygen activity, were higher than those at PO2 = 0.21 bar. The temperature dependence of the values converted to %[Sn2+] showed that the actual concentration of Sn2+ in the melts was 3–6% higher than expected at PO2 = 0.21 bar. These results are discussed in terms of the fining behaviour of melts. Keywords: Redox ratio, Multivalent element, Glass melts, Oxygen activity, Square wave voltammetry, Melt fining

Due to the drastic growth of the liquid crystal display (hereafter LCD) industry in the last decade, lots of waste glass is being produced. There are three types of waste glass derived from LCD glass manufacturers, LCD panel manufacturers and end-of-life LCD devices. Among them cullet from Lber glass (hereafter E-glass). However, the recycling of waste glass from LCD panel (LPWGCD glass is being recycled into a raw material for commercial electric continuous fi) and end waste glass is limited due to various reasons such as contaminants, toxic components and inhomogeneous glass compositions etc. Despite use of LPWG in the cement industry, it is not an effective form of recycling, considering the characteristics of LCD glass. In this work, to examine the possibility of recycling LPWG in the E-glass industry, several glass batches containing LPWG were prepared. First, some optical properties of the prepared and commercial E-glass were examined. Then, the viscosity and liquidus temperature (TL) were determined. The effect of LPWG was negligible in the transmission and color of the resultant glasses, considering that commercial bulk E-glass has an emerald-green color due to refractory corrosion. With an increase in the LPWG content, the isoviscosity and liquidus temperatures showed opposite behaviors; the temperature (TW) corresponding to the fiber forming viscosity (103 dPas) decreased, whereas the TL increased. Based on TW-TL, the replacement of 50 wt% of the original E-glass with LPWG was recommended. Additionally, economic and environmental effects were discussed.

The possibility of vitrifying the fly ash generated from municipal solid-waste incinerators and the immobilisation effect of toxic elements were investigated using several batches of fly ash and two kinds of common waste glass (waste glass from end liquid crystal display device and soda lime silicate waste glass). Fly ash could be vitrified by melting at 1300 °C prior to the introduction of a minimum of 30 wt% waste glass to each batch. Leaching tests were performed using the TCLP (Toxicity Characteristic Leaching Procedure) for three types of glass to identify the concentrations of five harmful elements (Pb, Ba, As, Cd, Cr) in the extraction fluid and a surface analysis using SIMS (Secondary Ion Mass Spectrometry) was performed to reveal the elemental distribution of the glass. The results confirmed that the regulatory levels (Pb

Although the presence of two different multivalent elements in glasses and melts has been of interest in the glass science community and the technology sector for some time, different opinions about their redox interactions have existed. Here, we examine the in situ Fe-redox potential and thermodynamics of the redox interactions of various multivalent elements that form pairs with Fe in the melt state by the potentiometry and voltammetry. For the secondary multivalent element in the Fe redox reaction, the same tendencies for the glass and melt states were observed. These findings confirm that the effect is derived from the melt state. The suggested interaction reactions at the equilibrium state based on the Fe-redox ratio are clearly demonstrated by the standard free energy. Additionally the difference of the Fe redox potential for the specific redox pairs is explained by the oxyegen equilibrium pressure. These results might be generalised to other redox pairs in other glass systems.

Cold-stretched pressure vessels made from austenitic stainless steel are widely used for storage and transportation of liquefied gases. Compared with conventional pressure vessels, cold-stretched vessels have lots of advantages such as having thin walls, light weight, and low energy consumption. However, pressure vessels can be subjected to alternating loads at cryogenic temperatures, so it is important to investigate the fatigue characteristics of austenitic stainless steel for cold-stretched vessels. This study presents the static and fatigue behavior of austenitic stainless steel 304 sampled from cold-stretched pressure vessels in accordance with the American Society of Mechanical Engineers code. To compare the mechanical properties and fatigue behavior of austenitic stainless steel 304 in as-received and cold-stretched conditions (9 % strain level), tensile and fatigue crack growth tests were performed at room and cryogenic temperatures respectively. Fractography of the fractured specimens was carried out using a scanning electron microscope. Kaltgestreckte Druckbehalter aus Edelstahl werden haufig fur die Lagerung und den Transport von verflussigten Gasen eingesetzt. Im Vergleich zu herkommlichen Druckbehaltern haben kaltgestreckte Gefase viele Vorteile, wie beispielsweise dunne Wande, geringes Gewicht und niedrigen Energieverbrauch. Jedoch konnen Druckbehalter wechselnden Belastungen bei kryogenen Temperaturen ausgesetzt sein, somit ist es wichtig, die Ermudungseigenschaften von Edelstahl fur kaltgestreckte Gefase zu untersuchen. Diese Studie stellt das statische und Ermudungsverhalten von Edelstahl 304 Proben aus kaltgestreckten Druckbehaltern in Ubereinstimmung mit der American Society of Mechanical Engineers Norm dar. Um die mechanischen Eigenschaften und das Ermudungsverhalten von Edelstahl 304 im Ausgangszustand und unter kaltgestreckten Bedingungen (9 % Dehnung) zu vergleichen, wurden Zug- und Ermudungsrisswachstumsversuche bei Raum- und Tiefsttemperaturen durchgefuhrt. Fraktografische Untersuchungen der gebrochenen Proben wurden unter Verwendung eines Rasterelektronenmikroskops durchgefuhrt.

In the present work, the application of LCD waste glass as a flux material substituting for the traditional feldspar in ceramic tiles was studied. The viscosity of LCD glass at the sintering temperature of the ceramic tile was found to be optimal for the dense solid that is obtained from the sintering of the glass powder. The sintered body containing LCD waste glass showed a dense microstructure due to the rich liquid. Even for full replacement of feldspar, neither pyroplastic deformation nor liquid exudation was observed. Overall, properties such as water absorption and the thermal expansion coefficient were positively affected by LCD waste glass substitution. Moreover, the mullite content in the sintered body was almost unchanged. These results were discussed in terms of the apparent viscosity and glass composition.

The objective of this paper is to propose a heuristic algorithm to optimize the railway track maintenance scheduling, a NP-hard problem, by reflecting conditions of the actual field more quickly and easily. We develop the mechanism based on Binary Artificial Bee Colony (BABC) and Binary Harmony Search (BHS), and verify their performance through simulation experiments. Our proposed BABC and BHS mechanisms were applied to problems composed of 30, 60, 100, and 200 operations for railway track maintenance scheduling to carry out experiments and analysis. On comparing it with the results solved by CPLEX, it is found that the mechanism could present an optimal solution within limited time by user.

Insoluble aggregates containing TDP-43 are widely observed in the diseased brain, and defined as “TDP-43 pathology” in a spectrum of neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS), Alzheimer’s disease and ALS with frontotemporal dementia. Here we report that Betz cells of patients with TDP-43 pathology display a distinct set of intracellular defects especially at the site of nuclear membrane, mitochondria and endoplasmic reticulum (ER). Numerous TDP-43 mouse models have been generated to discern the cellular and molecular basis of the disease, but mechanisms of neuronal vulnerability remain unknown. In an effort to define the underlying causes of corticospinal motor neuron (CSMN) degeneration, we generated and characterized a novel CSMN reporter line with TDP-43 pathology, the prp-TDP-43A315T-UeGFP mice. We find that TDP-43 pathology related intracellular problems emerge very early in the disease. The Betz cells in humans and CSMN in mice both have impaired mitochondria, and display nuclear membrane and ER defects with respect to TDP-43 pathology.

LCD glasses belong to the alkali-free alumino-borosilicate system and thus exhibit different properties from the traditional soda lime silicate glasses. In the present work, the replacement of feldspar by the waste glasses produced from LCD manufacturers was performed for porcelain sanitary ware. As the amount of LCD waste glasses increases, the sintered body showed a dense microstructure due to the rich liquid phase. Even under full replacement of feldspar, there was no pyroplastic deformation, except the exudation of liquid to the surface. The microstructure and mullite content were discussed in terms of the apparent viscosity and LCD glass composition, respectively. It is expected that LCD waste glasses enable the sanitary ware industry to save both raw material and energy simultaneously.