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Interactions among colloidal particles govern the hierarchical microstructure and its physical properties. Here, optical laser tweezers and Monte Carlo simulations are used to evaluate the effects of azimuthal rotation of Janus particles at the oil-water interface on interparticle interactions. We find that the capillary-induced attractive force between two Janus particles at the interface can be relaxed by azimuthal rotation around the critical separation region, at which the capillary force is ∼0.053 pN. Force relaxation leads to a decrease in capillary force around the critical separation region, resulting in a slight increase in the scaling exponent, compared to the theoretical prediction.

Three-dimensional NAND flash memory featuring dozens of vertically stacked memory cells is the state-of-the-art technology for most storage platforms. To fabricate three-dimensional (3D) NAND memory, lateral etching of the Si₃N₄ layer over SiO₂ is an essential step that is conducted through a wet etching process using a phosphoric acid-based etchant. Silyl-phosphate or highly selective nitride serves as an etching solution additive to control the SiO₂ layer dissolution rate. However, silyl-phosphate is prepared with an expensive monomeric silica precursor and at high reaction temperatures and generates environmentally harmful byproduct gases, such as HCl, HF, and CH₃OH. This study demonstrates that silyl-phosphate can be prepared using low-cost polymeric silica under a mild reaction temperature by changing the characteristic acidity of phosphoric acid. The possibility of tuning the phosphoric acid acidity was first studied by molecular dynamics simulations, and phosphoric acids with stronger acidity were prepared by the evaporation of water from H₃PO₄ (85%). The concentrated phosphoric acid enabled a fast reaction of polymeric silica and phosphate at a low reaction temperature (80 °C). The obtained silyl-phosphate lowered the SiO₂ layer dissolution rate, thereby yielding a Si₃N₄/SiO₂ layer etching ratio of up to 940. The proposed method offers an environmentally friendly production process for special chemicals used in 3D NAND flash memory fabrication.

In this work, we present an environment able to support users who perform big data analysis using distributed and parallel framework to web applications. JupyterHub and Jupyter Enterprise Gateway were used to develop user code in web environment, and Apache Spark is applied as a distributed and parallel framework. The spark cluster deployed at runtime works with Kubernetes as resource management application to maximize the use of resources on the backend and hence all components are container-based. We install all these customized components one of the largest supercomputer, fifth generation supercomputer, NURION, of KISTI. LDAP authenticator plugin and hostPath type volumes are employed to authenticate users of supercomputer and to bind storage respectively. This allows users to perform spark-based big data analysis on the supercomputer through the web interface with interactive environment.

To evaluate how triacetin and surfactant affect the solubilization and stability of citral, solutions containing citral were prepared with polyoxyethylene stearyl ethers and triacetin. Triacetin had a significant impact on the increment of saturation concentration of citral, and the citral solubility increased as surfactants were added. However, an interaction effect between triacetin and surfactant on citral solubility was not observed. At pH 3, the degradation rate constant of citral gradually decreased with a proportion of the triacetin concentration. Additionally, the chemical degradation of citral was considerably retarded in micelles built with surfactant. The surfactant with the smaller hydrophilic head exhibited higher citral stabilization ability than the one with the larger hydrophilic head; however, a negative interaction effect between triacetin and surfactant on citral stability in an acidic environment was observed.

As demand for high-performance computing power is increasing, operation management technologies like check-pointing, failure-aware task scheduling, and system simulations are becoming more important for the stable operation of the system. To maintain and manage a stable system, a detailed analysis of failed tasks is necessary. For this, this paper intends to analyze the characteristics of failed jobs in high performance computing system. Our contributions can be viewed in three ways. Firstly, it offers detailed analysis results of failed jobs based on the job logs of a currently operating supercomputer. Secondly, it offers not only an overall statistical analysis result but also identifies the distribution of the failed job submission inter-arrival time. Thirdly, it analyzes the occurrence probability of the event using hazard rate.

Several fields of science have traditionally demanded large-scale workflow support, which requires thousands of central processing unit (CPU) cores. In order to support such large-scale scientific workflows, large-capacity cluster systems such as supercomputers are widely used. However, as users require a diversity of software packages and configurations, a system administrator has some trouble in making a service environment in real time. In this paper, we present a container-based cluster management platform and introduce an implementation case to minimize performance reduction and dynamically provide a distributed computing environment desired by users. This paper offers the following contributions. First, a container-based virtualization technology is assimilated with a resource and job management system to expand applicability to support large-scale scientific workflows. Second, an implementation case in which docker and HTCondor are interlocked is introduced. Lastly, docker and native performance comparison results using two widely known benchmark tools and Monte-Carlo simulation implemented using various programming languages are presented.

Recently, Importance of power management circuit technology is increased with the development of portable electric devices. This paper presents a high performance DC-DC buck converter for mobile applications. Especially, presented design have low ripple voltages and driving capability of large load current. A designed voltage mode 2-phase DC-DC converter is implemented in a 0.35μm CMOS process, and the overall size is 2.35×2.35mm. The peak efficiency is 91% with a 4MHz frequency and the maximum load current is 4A. 요 약 최근 휴대용 전자기기의 발달로 인해 전력관리회로 기술의 중요성이 증가하고 있다. 본 논문에서는 휴대기기를 위한 고성능 DC-DC 벅 변환기를 설계하였으며 특히 출력에서의 리플 전압을 작게 하고 수 A급의 대용량 출력 전류의 안정적인 구동이 가능하도록 2-페이스 구조를 사용하여 설계하였다. 설계된 전압모드 2-페이스 벅 변환기 는 0.35μm CMOS 공정을 통하여 칩으로 제작되었고 전체 칩의 크기는 2.35×2.35mm, 동작주파수는 4MHz, 최대 4A의 부하전류를 구동할 수 있으며 최대 변환효율은 91% 이다.

Parallel download protocols that establish multiple TCP connections to distributed replica servers have the potential to reduce file download times and to achieve server-side load balancing. Unfortunately, parallel download protocols are inherently unfair towards single-flow downloads and may even starve them. This paper presents a fairness-aware parallel download protocol that allows the dynamic mitigation of throughput and fairness in distributed networks. The key novelty is a receiver-based framework that allows a dynamic adjustment of the congestion and rate control of each subconnection. The proposed Fairness-aware Control Coordinator (FCC) adjusts the priority of the subconnection between the TCP-fair rate (high priority) and the TCP-LP fair rate (low priority) according to the dynamics on the network without adding to the unfairness towards other downloads. Simulation results show the flexibility of the proposed protocol in balancing performance and fairness.

In the development of WPC windows, it is of utmost importance to have a proper assessment process on the functionality and durability, which is necessary to assure that those properties are maintained during the lifetime of the products. The current paper investigates the WPC windows’ usability, which was done through the initial performance (water absorption: 2.30%, flexural modulus: 1,610 MPa, etc.) and reliability evaluation (color difference (ΔE), surface analysis, degradation tendency after accelerated life test) of the developed WPC windows. A degradation prediction model for WPC is also presented. In the development of WPC windows, it is of utmost importance to assure that those properties are maintained during the lifetime. The current paper investigates the WPC windows’ usability, which was done through the initial performance (water absorption 2.30%, Flexural modulus 1.610 MPa, etc.) and reliability evaluation (Color differences after accelerated life test) of the developed WPC windows. In addition, it presented degradation prediction model for WPC windows.

Today the light of mankind since the dawn of mankind and that they were living "lives" on the huge influence across space is a dynamic energy. Because of this, when all human beings with the light and you can feel more comfortable with a stable mind to the beauty and the pursuit of happiness is to have instincts. In this paper, a fuzzy control system using a combination of external environmental factors, respectively, the conversion of quantitative uncertainty information into the LED lighting is designed to express algorithms, available in indoor circadian control circuit was designed and fabricated LED. Factor in the external environment temperature, humidity, and light intensity values to the controller through the sensor to accept these values and the optimal values for lighting the fuzzy control algorithm is converted into human emotion to feel comfortable to express through the dimming control LED lighting.

This paper investigates several problems associated with optical multicast routing and wavelength assignment in sparse-splitting optical networks for interactive real-time media distribution. Unfortunately, the constrained multicast routing with optimized wavelength assignment leads to NP-complete condition. Thus, in this paper, a virtual-node-based multicast routing algorithm is first proposed to satisfy the requirements of interactive real-time multicasting as well as the constraints from underlying optical networks. For the constructed multicast tree, we then associate an effective wavelength assignment algorithm. The experimental results show that the proposed algorithm combination performs well in terms of (1) the wavelength channel cost, (2) the maximum variation of inter-destination node delays, (3) the signal quality, and (4) the number of wavelength conversions.

Advanced collaboration environments are extensively utilized for distance learning, e-science, and other distributed global collaboration events. In such environments, high-quality and seamless media services play an important role in improving the quality of user experience to participants. In this paper, to support high-quality media-based services, we design open media service architecture for advanced collaboration environments, by combining the open interface for state-of-the-art media tools, the performance monitoring tools for devices and networks, and application-level adaptation schemes for media streaming. By implementing the proposed architecture on top of an open-source Access Grid (AG) collaboration toolkit, we verify that high-quality collaboration among several collaboration sites can be effectively realized over a multicast-enabled network testbed with improved media quality experience.

As the demand for real-time IP media transport over multi-point delivery environments increases, it is essential to monitor the time-varying status of both network metrics (i.e., delay, jitter, and loss) and system metrics (i.e., CPU and memory utilization). In this paper, we propose and implement a new monitoring system for the high-quality real-time media delivery over multicast-enabled network. It monitors the time-varying conditions of both the multicast network and the node system. When the media performance degrades, the proposed monitoring system attempts to pinpoint the cause of performance degradation to improve the end-to-end performance. The experimental results show that we can effectively infer the cause of performance degradation using the implemented prototype of the proposed monitoring system.

In this paper, for manufacturing a custom-made shoes, shape of foot acquired three-dimensional measurement device which makes shoe-last data for needing a custom-made shoes is founded on artificial intelligence technique and it shows method restoring to the original shape in optimized state. the developed system for this study is based on PC which uses existing three dimensional measurement method. And it gains shoe-last and data of foot shape going through 8 CCD(Charge Coupled Device) Which equipped top and bottom, right and left sides and 4 lasers which also equipped both sides and upper and lower sides. The acquired data are processed image processing algorithm using artificial intelligence technique. And result of data management is better quality of removing noise than other system not using artificial intelligence technique and it can simplify post-processing. So, this paper is constituted hardware and software system and it used neural network for determining threshold value, when input image on pre-processing step is being stage of image binarization and present that results.

Biometrics is getting more and more attention in recent years for security and other concerns. So far, only fingerprint recognition has seen limited success for on-line security check, since other biometrics verification and identification systems require more complicated and expensive acquisition interfaces and recognition processes. Hand-Geometry has been used for biometric verification and identification because of its acquisition convenience and good performance for verification and identification performance. Hence, it can be a good candidate for online checks. Therefore, this paper proposes a Hand-Geometry recognition system based on geometrical features of hand. From anatomical point of view, human hand can be characterized by its length, width, thickness, geometrical composition, shapes of the palm, and shape and geometry of the fingers. This paper proposes thirty relevant features for a Hand-Geometry recognition system. However, during experimentation, it was discovered that length measured from the tip of the finger was not a reliable feature. Hence, we propose a new technique based on Genetic Algorithm for extraction of the center of nail bottom, in order to use it for the length feature.

Paving the road for sulfur: A unique electrolyte composition designed for the development of stable lithium-sulfur batteries with high energy. A battery with a high and stable capacity is prepared by using an electrolyte containing a dissolved catholyte-type compound, that is, Li2 S8 polysulfide. The cell is characterized by a capacity approaching the theoretical value at a working voltage of 2.1 V, which is remarkable compared to conventional lithium ion batteries.

An alternative configuration of anode and cathode, i.e. nanostructured Sn–C and hollow carbon spheres–sulphur composite electrodes, are characterized here in an ether-based electrolyte for application in sodium ion–sulphur batteries. The enhanced morphology of the electrodes, the high values of conductivity and of sodium transference number, as well as the good stability of the electrolyte are unique properties that are expected to allow the development of a new sodium ion cell. Indeed, the results reported in this work show that this cell can provide a remarkable capacity of 550 mA h g−1 and an expected theoretical energy density of 550 W h kg−1.