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In a player-versus-player game such as StarCraft II, it is important to match players with others with similar skills. Studies modeling player skills were conducted, with 47.3% and 61.3% performance. In order to improve the performance, we collected 46,398 replays and compared features extracted from six sections of replays. Through the comparison of the six datasets we created, we propose a method for extracting features from a single replay. Two algorithms, k-Nearest Neighbors and Random Forest, which are most commonly used in related studies, are compared. Our research showed a outperforming accuracy of 75.3% compared to previous works. Although no direct comparison has been made with the current system, we conclude that our research can replace the placement games of five rounds.

The players are divided into seven leagues depending on their skill in StarCraft II. Since it is most ideal for players with similar skills to play games, it is important to be included in the right league. This paper proposes a method to predict a player’s league. Our proposed method is extracting control features from the replay, and introduce a useful feature that is not well known. We use a Random Forest for verifying the importance of features.

As interest in climate change has increased in recent years, research on alternative energy sources is becoming more active. Fuel cells are one of the most promising electrochemical energy conversion devices that hold many advantages. In particular, polymer electrolyte fuel cells (PEMFCs) are attracting much attention due to their high power density and relatively good portability. In PEMFC systems, the main cost is due to the catalyst in terms of high cost of platinum group metals. This derives the need to understand the way how to get a highly active and stable electrocatalysts. In general, Pt/C is most widely used catalyst because it has a large surface area for platinum anchoring, high electrical conductivity, and suitable pore structure for transferring reactant and product. However, carbon support undergoes carbon corrosion which is happened thermodynamically favored in fuel cell operation conditions. This phenomenon occurs at the surface of the carbon and it makes void places under the Pt nanoparticles. This mechanism causes losing electrochemical active sites. And there are also agglomeration and sintering of Pt particles on the carbon surface. Consequentially, carbon corrosion and platinum dissolution result in reduced electrochemical surface area (ECSA) and interferes long-term operations. Thus, electrochemically stable support materials need to be developed. In various alternative material candidates, our group selected the TiO2 based support because it exhibits excellent chemical stability under severe acidic condition and offers the opportunity to modifying electronic structure of platinum particles. However, hindrances such as low electrical conductivity, catalytic activity, and surface area limit the direct use of TiO2 as a catalyst support. To remedy these drawbacks, we have designed carbon-titania composite support based electrocatalysts. These noble TiO2 – carbon hybrid support was synthesized from electrospun nanofibers and platinum nanoparticles are deposited on a support by microwave-assisted polyol process. Through our new approaches, we can obtain the electrocatalysts which have a unique 3D pore structure with higher surface area, modified electronic structure with increased intrinsic activity and extended cyclic durability.

The dynamics and trends of the portable electronics market drives researches to develop energy sources with newer properties. The advancement of augmented reality has opened windows of opportunities for optical modification of batteries to be implemented in transparent devices similar to the heads-up display. While realization of products is still in its infant ages, it is without question that technology will pursue such directions. Zinc air batteries hold numerous strongholds that advertise itself as the post lithium ion technology. The system’s abundant energy density along with advantages such as cheaper materials cost and environmentally friendliness has prompted this study to further investigate its potentials. In this presented work, we report the first ever fabrication of transparent secondary zinc air batteries. The system utilizes a commercial transparent stainless-steel mesh as the current collectors. Owning to the unique structure of the battery, the cell exhibits extreme mechanical versatility as free bending without tariffing the cell performance is possible. The average transparency in the visible light region was recorded at 48.8%. Electrochemical analysis revealed stable galvanostatic discharge-charge cycle operations, exceeding more than 100 turnovers for every bended angle. Electrochemical Impedance Spectroscopy results observed minimal deviation between the conformational states. This research’s potential lies in the simple technique to achieve optical properties in power sources that can be extended to further areas. Mass scale production is also opportunistic as the process utilized are favorable enough for large productions.

High purity carbon nanotubes are synthesized by methane decomposition using an arc-jet plasma of high temperature (5000–20,000 K). Since the arc-jet plasma process is continuous and easily scalable, it is a promising technique for the large-scale commercial production of carbon nanotubes. In this experimental work, the arc-jet plasma is generated by a dc non-transferred plasma torch, in which a mixture of argon and hydrogen is used as a plasma forming gas and nickel powder as a metal precursor. Morphology, crystallization degree and purity of the carbon nanotubes in the soot produced under various processing conditions are evaluated by using scanning electron microscopy, transmission electron microscopy, Raman spectroscopy and thermogravimetric analysis. From the results of these material analyses, we have found that multi-walled carbon nanotubes of high purity were produced in the optimal operating condition. In addition, the thermal plasma characteristics for the carbon nanotubes growth are discussed from numerical simulation result of the arc-jet plasma.

Boron nitride nanotubes (BNNTs) are synthesized by the arc-jet plasma of high temperature (5000–20 000 K), which is generated by a dc non-transferred plasma torch with a mixture of argon and nitrogen gas. The BNNTs produced by the thermal plasma process are resulted from the chemical reaction of a precursor material of hexagonal boron nitride with catalytic metal powders of Ni and Y introduced into the hot arc-jet plasma flame, which is ejected inside the cylindrical carbon reactor. The synthesized materials are evaluated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electron energy loss spectroscopy (EELS). These material analyses reveal that multi-walled nanotubes including single- and double-walled ones with high crystallinity are synthesized in quantity, and that the diameter of nanotubes is estimated in the range of 3–10 nm.

Thermal plasma characteristics of transferred plasma torches are numerically and experimentally investigated under atmospheric conditions to find the effects of operating variables and electrode arrangements on them. A control volume method and a modified SIMPLER algorithm are used for numerical analysis, and the temperature distributions of argon plasma are calculated in different torch operating conditions of a typical transferred arc torch. Transferred plasma torches are designed and fabricated, which have six different electrode arrangements, respectively, consisting of a conical rod cathode and a nozzle in the torch, and a distant anode material. The dynamic behaviors of arc voltage are measured to obtain stable arc conditions, and a similarity criterion is determined to analyze static behaviors of arc voltage. For predicting the heat transfer rate to melted material from arc column, measurements are made for the heat loss at the anode material and fractions of input power transferred to the anode. Furthermore, thermal plasma temperatures are measured by the optical emission spectroscopy of an Ar I line. As a result of the present work, an appropriate electrode configuration and operating conditions for waste melting process are presented for the optimization of transferred plasma torches.

Summary form only given. For the cleaning treatment of hazardous waste gases by pyrolysis, thermal plasmas have been introduced taking advantage of their extremely high temperature and enthalpy. However, the high-temperature decomposition region of a thermal plasma jet, having steep temperature gradients both in the radial and axial directions, is so narrow that the waste gas injected into it has difficulty in mixing up uniformly with the fast hot thermal plasma in a pyrolysis reactor. In this experimental study, we have measured the temperature and chemical composition of thermal plasma in a pyrolysis system to find optimum conditions for uniform mixing of waste gases. An experimental setup includes a DC thermal plasma torch with hollow electrodes, a decomposition reactor containing mixing chamber, and an enthalpy probe system combined with quadrupole mass spectrometry for measurements of temperature and chemical composition. Diagnostics with the enthalpy probe svstem are made while operating the system under the following conditions: air plasma-forming gas flow rate of 100 slpm, nitrogen purging gas flow rate of 200 slpm, and torch input power of 60 kW. Axial and radial measurements are carried out to obtain temperature and chemical composition distributions depending on experimental conditions, such as diameters of nozzle electrodes and types of gas injection rings. By comparing radial uniformities of nitrogen mole fractions and temperature distributions, we can figure out the effects of design variables on mixing ratio in the reactor. The mixing effects are discussed in terms of turbulent flow characteristics concerned with the injection ring tvpe and the plasma jet column size determined from the nozzle diameter. We also examine the correlation between variances in radial uniformities and axial plasma characteristics. From the present experimental results, some thermodynamic characteristics of the plasma in the pyrolysis system will be revealed, and the decomposition efficiency is expected to be improved in the field of thermal plasma waste gas treatment.

Summary form only given. Diamond films are grown on the molybdenum substrate by a chemical vapor deposition (CVD) using thermal plasma jets mixed with methane and hydrogen. Morphologies of the diamond films grown under various processing conditions, such as substrate temperature and the ratio of hydrogen to methane, are evaluated by scanning electron microscopy (SEM). In addition to the diamond film evaluation, an optical emission spectroscopy (OES) of the thermal plasma jets during the CVD process is performed to examine the chemical and ionizational states of the plasma. Such an OES makes it possible to determine Boltzmann temperature from the selected argon electronic transitions, electron number density from Hbeta emission, vibrational and rotational temperatures from C2 emission (d3Pigrarra3Piu). From the morphology analysis and diagnostic results obtained, the effect of plasma conditions on the diamond film growth will be discussed.

Abstrast High temperature fuel cell has been highlighted for its use in the wide range of the applications because of its simplified system due to easier integration and high energy efficiency.[1-2] There are several fascinating reasons for operating PEMFC at high temperature and low related humidity such as electrochemical kinetics, CO poisoning of Pt/C catalyst and water management. Also, the lifetime targets (5000 h stated objective by DOE) must be achieved while the costs of the fuel cell systems must be reduced concurrently.[1] In order to ameliorate the durability and lifetime of PEMFCs, a better analyzing of failure tools and corresponding mitigation methods are urgently required.[2] In the development of membranes that can effectively operate under higher temperature and lower humidity conditions, researchers have suggested organic-inorganic composite membranes with inorganic particulate additives.[3] Some of the composite membranes with particulate additives have shown improved fuel cell performance at high temperature and low humidity because of improved hydroscopic and thermal stability. Nevertheless, in practice, composite film casting by solvent evaporation or extrusion is often challenging due to particle agglutination. Recently, ceramic nanofibers have been prepared via electrospinning.[4] The uniformly dispersed 3-dimensional foam-like inorganic nanofibrous web completely resolved the agglomeration issue of particulate additives. The aspect ratio of the fibers was extremely high thereby providing additional mechanical strength to the composite membrane that could not be achieved by particulate additives. In this study, we prepared inorganic nanofibrous web supported polymer electrolyte membrane to increase operating temperature of the pristine polymer electrolyte membrane. Accelerated life-time tests (ALT) by changing the voltage sweep were developed to have better understanding of the degradation mechanisms in the fuel cell system. Further, factors of degradation were studied by conducting the electrochemical methods and characterizations. Gravimetric swelling by water of the Aquivion-impregnated inorganic nanofibrous webs as a membrane was higher than Aquivion cast film (32.8% vs. 17.5%) but more importantly, no length change in x- and y-axis was observed in wet state due to the presence of rigid inorganic nanofibrous webs uniformly distributed in the membrane. Therefore, no areal expansion of membrane is expected in the actual fuel cell test that would be beneficial to mechanically stable operation. A single cell with Aquivion/phosphate modified inorganic nanofiber composite membrane showed the best performance at partially humidified condition of 120 °C / 40% RH. It was expected that the higher water retention of the Aquivion/ phosphate modified inorganic nanofiber composite membrane played a beneficial role that the phosphate functionality enhanced proton conductivity by enhancing proton transfer through the Grotthus mechanism at higher temperature and the lower humidity conditions. References [1] B. Wahdame et al., Journal of Power Sources 182 (2008) 429–440 [2] S. Zhanga, et al., International journal of hydrogen energy 34 (2009) 388–404 [3] P. Costamagna, et al., Electrochimica Acta 47 (2002) 1023-1033. [4] Yao, Y et al.. Electrochemistry Communications 13 (2011) 1005-1008.