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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.

Traditionally, high-performance computing (HPC) systems have been extensively utilized in many science fields including big data analysis and machine learning. Such large-scale HPC resources typically use the queue management systems which prefer space-sharing method to allocate resources. In space-sharing method, it is natural that a queue waiting time occurs until the resources are available if resources are not sufficient. When the predicted information on such a waiting time is provided, it is possible to improve the performance of scheduler. For this, in this paper, we propose a prediction method of queue waiting time based on the job log file created in the HPC system actually under operation. The prediction technique presented in this paper largely comprises three phases. The first phase is a pre-processing of data in constant time intervals. In the second phase, major features are selected through a factor analysis and clustering is conducted based on the selected features. In the third phase, a waiting time of the next job is predicted using the sliding window method based on the jobs that were clustered.

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.

Real-time multimedia streaming over the Internet is rapidly increasing with the popularity of user-created contents, Web 2.0 trends, and P2P (peer-to-peer) delivery support. While many homes today are broadband-enabled, the quality of experience (QoE) of a user is still limited due to frequent interruption of media playout. The vulnerability of TCP (transmission control protocol), the popular transport-layer protocol for streaming in practice, to the packet losses, retransmissions, and timeouts makes it hard to deliver a timely and persistent flow of packets for online multimedia contents. This paper presents TCP-real-time online multimedia environment (ROME), a novel transport-layer framework that allows the establishment and coordination of multiple many-to-one TCP connections. Between one client with multiple home addresses and multiple co-located or distributed servers, TCP-ROME increases the total throughput by aggregating the re- sources of multiple TCP connections. It also overcomes the band- width fluctuations of network bottlenecks by dynamically coordinating the streams of contents from multiple servers and by adapting the streaming rate of all connections to match the bandwidth requirement of the target video.

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.

Several fields of science have traditionally demanded large-scale workflow support, which requires thousands of CPU cores or more. In this paper, we investigate ways to support these scientific workflows in a heterogeneous environment in which cluster computing resources are integrating with cloud computing resources. Specifically, we first propose an architecture that utilizes cloud resources to address load balancing issues. For that, the proposed architecture measures the status of job queue on the front-end node, and then dynamically creates virtual machines from cloud pools based on the measured results to expand computing resource of the cluster. Next, we present experiment results of computational performance in hybrid infrastructure where the virtual and physical nodes are mixed.

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.

This Nowadays, along with popularity of application and use of network technologies, the structure of network is being complex and enormous to support emerging applications. A NMS (Network Management System) is required to support emerging services through the complex network structure. In this paper, we present an on-going work called SOLA (Smart One-view Look and Analysis) to integrate the existing NMSs. SOLA has three remarkable features. First, it can reduce the CAPEX/OPEX by sharing a common platform. Second, since SOLA is a web application complied with HTML 5, it can be run on emerging smart devices such as smart phone and table PC as well. Lastly, it can provide an end-to-end analysis since the event messages are collected from an entire network.

It is very difficult to identify the location of bottlenecks when there is deterioration of Quality of Service (QoS) because current Internet service is the complicate structure which is provided through a number of ISP. This paper proposes bottleneck detection algorithm which can detect the bottleneck point easily and efficiently even though there is no prior knowledge of the network connection status. The execution procedure of the proposed algorithm can be largely divided into two phases. In the first phase, the proposed algorithm finds the choke point which is suspected to be the bottleneck point using Recursive Packet Train (RPT). In second phase, it identifies the bottleneck point by monitoring packet process time of the detected choke point. For this, this paper proposes two methods. The first method monitors packet process time of the choke point utilizing timestamp option. This method has the advantage which can monitor the bottleneck point without increasing network load because it uses passive monitoring approach using the IP header part of the data packet of the actual users. But agent should be run in all of servers and clients. The second method monitors packet process time of the choke point utilizing ICMP packet. This method is possible to detect the bottleneck point by running agent solely in client without running agent of servers because ICMP packet which is sent to the senders to report the problems found while processing IP packet in routers.

Parallel download protocols that establish multiple TCP connections to distributed replica servers have the potential to reduce file download time and to achieve a server-side load balancing. Unfortunately, parallel download protocols are also inherently unfair towards single-flow downloads and may even starve them. This paper presents TCP-ROME, a parallel download protocol that allows a dynamic mitigation of throughput and fairness. The key novelty is a receiver-based framework that allows a dynamic adjustment of the congestion and rate control of each subconnection. TCP-ROME offers two usage modes: a binary mode where the congestion control of each subconnection can be switched between a TCP-fair rate (high priority) and at a TCP-LP fair rate (low priority), and a more complex range mode where the aggregated throughput aims at meeting a specified target rate. Apart from the protocol specification, this paper develops novel analytical throughput models for TCP-LP and for TCP-ROME. The models are validated via simulations. Extensive simulation scenarios show the flexibility of TCP-ROME in mitigating performance for fairness.

As the Internet evolves into an irreplaceable service-oriented infrastructure, a key issue to consider is that of creating and managing a rich variety of novel services while keeping aware of individual requirements for QoE (Quality of Experience) guarantee. In this paper, we present our on-going effort of designing a futuristic service framework for flexible media-oriented service composition in Future Internet. In our framework, media-oriented contents, generic service, and programmable infrastructure cooperate to flexibly compose media-oriented services with diverse requirements according to user's context and resource heterogeneity.

Live streaming of multimedia content over the Internet is rapidly increasing, e.g. with the Web 2.0 and via peer-to-peer systems. While many homes today are equipped with sufficient bandwidth (DSL) to support high quality live streaming, the quality of experience of a user is dismal: the video resolution and size is small and the displaying is often interrupted. One of the key problems arises because TCP is used as the underlying transport layer protocol: packet loss, retransmissions and timeouts prevent TCP from delivering a timely, steady flow of packets and thus inhibits the provision of online multimedia content. This paper presents TCP-ROME, a novel transport-layer framework that allows an establishment of multiple TCP connections between one client with possibly multiple home addresses and multiple co-located or distributed servers. The download over multiple TCP connections increases the total throughput by aggregating the resources of multiple TCP connections. Moreover, TCP-ROME provides the means to overcome bandwidth fluctuations and network bottlenecks by dynamically coordinating the downloaded content from the different servers and by coordinating and adapting the streaming rate of the different connections to meet the bandwidth requirements of the video.

As the demand for high-quality real-time media service through multicast-enabled AG (access grid) increases, the end-to-end QoS (quality of service) provisioning of the media service has become very important. To guarantee the end-to-end QoS, it is essential to monitor the time-varying status of both network (i.e., delay, jitter and loss) and system metrics (i.e., CPU and memory utilization). In this paper, we propose a new service for the AG, to monitor the time-varying conditions of both multicast networks and the AG node systems. When the performance of the AG degrades, the proposed monitoring attempts to pinpoint the cause of performance degradation and explores corresponding reactions to improve the end-to-end performance of the AG. The experimental results show that the proposed monitoring service is really useful in improving the quality of media service for the AG.

As real-time media applications based on IP multicast networks spread widely, end-to-end QoS (quality of service) provisioning for these applications have become very important. To guarantee the end-to-end QoS of multi-party media applications, 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, targeting the multicast-enabled AG (Access Grid) a next-generation group collaboration tool based on multi-party media services, the applicability of hybrid monitoring scheme that combines active and passive monitoring is investigated. The active monitoring measures network-layer metrics (i.e., network condition) with probe packets while the passive monitoring checks both application-layer metrics (i.e., user traffic condition by analyzing RTCP packets) and system metrics. By comparing these hybrid results, we attempt to pinpoint the causes of performance degradation and explore corresponding reactions to improve the end-to-end performance. The experimental results show that the proposed hybrid monitoring can provide useful information to coordinate the performance improvement of multi-party real-time media applications.