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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.

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.

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.

This research was initiated to analyze the periods of spring green-up and winter leaf discoloration of three ornamental grasses which have potential to be widely used with seed propagation. Two native grasses of Arundinella (Arundinella hirta var. ciliata Koidz), fountaingrass (Pennisetum alopecuroides (L.) Spreng), and switchgrass (Panicum virgatum L.) was tested. Spring green-up were evaluated after one year growth from seed propagation on April 1, 2009. Arundinella started with quick pick of spring green-up during 13 th to 20 th of May. Fountaingrass and switchgrass showed relatively slow picks of green-up during 20 th to 27 th of May. However, winter leaf discoloration started on swtichgrass and fountaingrass but Arundinella terminated relatively slowly. Swtichgrass showed the pick discoloration during 8 th to 15 th of October from the bottom to top parts of the plant. Fountaingrass showed the pick winter discoloration started from bottom to top parts during the 22 nd to 29 th of October. However, Arundinella showed relatively slow discoloration from upper to bottom parts during October 29th to November 5 th . Arundinella showed a relatively higher ornamental value with 125 days of the complete green period compared than fountaingrass and swtichgrass which maintained approximately 105 days of green period.

본 연구는 산마늘 절임제품을 대상으로 소비자들의 구입행태와 선호도를 분석하여 향후 산마늘 절임제품의새로운 제품개발과 마케팅 전략 수립 등에 필요한 기초자료를 제공하고자 수행하였다. 산마늘 절임제품에 대한 소비자들의 일반적인 소비행태 분석을 수행하였으며 산마늘 절임제품의 속성별 중요도 도출을 위해 컨조인트 분석을수행하였다. 그리고 시장세분화를 위한 군집분석과 시장점유율 예측을 위한 Logit 모형을 적용한 시뮬레이션 등을 수행하였다. 소비자 선호도 분석을 위한 컨조인트 분석결과, 소비자들은 산마늘 절임제품의 제품 포장용기를 제품 구매시 가장 중요하게 고려하며 다음으로 절임간장의 콩 원산지인 것으로 분석되었다. Abstract: The purpose of this study is to obtain the basic information for developing new product and marketingstrategies of salted wild vegetable. This study analyzes consumer's consumption behavior and preference onsalted Allium victorialis using the conjoint analysis. The result shows that ‘Container’ is the most importantfactor among various attributes of salted Allium victorialis, followed by ‘Origin of Salting Sauce Soy’, ‘Price’,‘Traditional Food Quality Certification’, and ‘Area of production’.Key words

The redox reaction M (x+n) + n/2O ?2 + M x+ + n/4O₂ of multivalent ions in glass melts influences the melting process and final properties of the glass including the fining (removal of bubbles), infrared absorption and homogenization of melts, reaction between metal electrodes and melts or refractory and melts, and transmission and color of glass. In this review paper, the redox behaviors that occur frequently in the glass production process are introduced and the square wave voltammetry (SWV) is described in detail as an in situ method of examining the redox behavior of multivalent ions in the melt state. Finally, some voltammetry results for LCD glass melts are reviewed from the practical viewpoint of SWV.

The core of the CNG fueling station is the compressor and most of CNG compressors in Korea require lubrication. Lubrication oil of CNG compressor that can be transferred into the pressure regulators and the engines of fueling system can cause a negative effect on NGV(Nature Gas Vehicle) performance during refueling due to oil Carry-over. In order to avoid the problem, it is necessary to enhance the quality of the compressed natural gas by measuring quantitatively the amount of the transferred oil. In this research, a sampling device and sampling tube were developed, which can be used with a gravimetric method of detection to measure CNG oil Carry-over. In addition, CNG samples were taken at 6 pre-selected CNG fueling stations and analysed for their trace oil Carry-over. The measured total oil Carry-over ranged from 2.569 to 6.509 ppm. This test measurements were compared with those of previous studies to verify the results.

Korea Productivity CenterThis is a report on the history and current status of production planning and control activities in South Korea with regard to Industrial Engineers’ (IEs’) role. One of the main characteristics of Korean global companies is that they make good use of IEs not only in their production but also in higher strategic fields like supply chain management. In these companies it is well demonstrated that instead of adding small part of IE skills to traditional engineers, it is much more competitive to have IEs work with them as a team since IEs are fully proficient in every kind of productivity and quality improvement tools. It is also observed that IEs become more productive when they have good domain knowledge in their own industries like semi-conductor, automobile, telecommunications, steel, shipbuilding, etc. So teaching the basics for manufacturing processes to IE students seems very important for their future career development.

Alkali free alumino-borosilicate display glasses that serve as the window in a TFT-LCD (hereafter LCD) device not only have few impurities but also high homogeneity to guarantee the quality of the display. These characteristics of LCD glasses enable the possibility of recycling LCD glass cullet as a raw material for commercial soda lime silicate glasses from the perspectives of the raw material costs and the energy saving. In the present work, several batches containing LCD cullet for two commercial model glasses were prepared and melted in the laboratory. According to several properties of the melts and the glasses, there was no serious change in the properties with up to 9 wt% replacement of the flint glass and 11 wt% replacement of the low iron flat glass by the LCD cullet. Currently, LCD cullet is being used successfully in a number of industrial plants for the production of flint glass in Korea. Two-thirds of flint bottle glasses contain B2O3 component derived from LCD cullet.