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A discretized positioning circuit (DPC) based on a resistive network has been developed to reduce the size of a gamma-ray detection system using multi-anode photomultiplier tubes (MA-PMT) in an array, because it can drastically decrease the number of output channels. The output signal from the gamma-ray detection system is a current pulse generated in each tube that contains information about the gamma-ray energy and detecting position in the array. The output current pulse is distributed to four outputs according to the resistance ratio of the resistive network in the DPC, and the detected position is estimated using the height values of the four distributed current pulses. However, owing to parasitic capacitors of MA-PMT connected in parallel to resistors in the resistive network, the four output pulses are affected by the RC time constants. In particular, when the duration of the input signal is not long enough, the height values of the distributed pulses are reduced, and thereby the position error increases significantly. In this paper, we present a new distortion correction method that considers the pulse duration and the RC time constant. In order to correct the position error, we employed homography, which is a coordinate transformation method. The ideal grid was mapped to a new grid for the distorted position. Using this method, error correction was completely achieved, even for short current pulses.

Although the fringe-field-switching (FFS) mode based on a two-domain (2D) electrode structure has been widely used for wide viewing angle in a liquid crystal display (LCD), it still suffers from color shift and asymmetric luminance distribution at off-axis. We propose a four-domain (4D) electrode structure for wide viewing angle characteristics in an FFS LCD. We demonstrate that the use of the 4D electrode structure instead of the 2D-chevron structure can reduce the off-axis color difference from 0.038 to 0.010 at a low gray level and from 0.019 to 0.002 at a mid-gray level. Moreover, the off-axis gamma distortion is reduced from 0.159 to 0.007.

The liquid crystal alignment method using a UV-curable polymer has been reported for the zero pre-tilt angle of liquid crystals (see the paper by Oh in Optics Express, vol. 23, p. 1044, 2015). In this paper, we report the electro-optical characteristics and parameters related to the image quality of a fringe-field switching cell fabricated using the field-induced UV-alignment method as functions of the monomer concentration and the UV irradiation time. The results show that the field-induced UV-alignment method has a high potential for practical display applications.

We demonstrate a continuous-wave 460-nm com- pact visible laser module having a footprint of 75 mm × 25 mm × 25 mm. This blue light source is achieved through single-pass second harmonic generation with a distributed Bragg reflec- tor tapered diode laser as a single-frequency pump source at ∼920 nm in a periodically poled MgO-doped lithium niobate crystal with a planar waveguide. The compact blue laser module reached an optical output power of 286 mW with the highest optical conversion efficiency of 11.6% at room temperature. The power stability of the blue light from the laser module is measured at an output power of 268 mW with a variation of ±3.5% during a period of 1 h.

With recent advancement in technologies used at home, smart home environment allows various resources such as device, network, or content to be connected to one another. Their configurations are changed by dynamic bindings at any time. In this smart home environment, a minor problem in a resource can trigger serious failures in home network services by causing multiple faults to the related resources simultaneously. To solve this problem, it is essential to analyze the dependency between resources and also to diagnose home network faults autonomously. This paper proposes the effective fault diagnosis system based on resource relation map which is dynamically constructed by information convergence model of heterogeneous home resources. The proposed system provides the tracing method for finding the root cause of a fault using the resource relation map. The resource relation map represents the snapshot of home situations at the given time. The proposed fault diagnosis method allows building cost effective remote maintenance system with high availability and manageability by tracing the fault cause along the dependency between resources using graph-style resource relation map as if humans trace the cause of problem. In addition, it can contribute to realize an autonomic fault management system for smart home. In this paper, the prototype of the proposed system is implemented and evaluated for performance in accuracy and latency of fault diagnosis in a real environment. The experimental results show that the proposed system, especially with the suggested back tracing diagnosis system, yields remarkable performance for home network fault diagnosis.

With the advent of smart home devices including Smart TV or smart appliances, home becomes smarter. Smart home is a complex environment where heterogeneous smart devices and appliances are connected to each other to provide various smart services. As the home environments become smarter and more complex, the need for an effective managing mechanism with minimum user's intervention is growing. However, just only putting together all the individual information of each resource is not enough, since it is very hard to catch out overall home situation without the relation information between the managed resources. In this paper, we propose a resource-aware management system with hierarchical smart home resource model, using the home context information which defines the information convergence model of heterogeneous home resources and builds a home knowledge by constructing a resource relation graph. The proposed system can accelerate deployment of advanced future smart home service features such as context-aware dynamic service composition, autonomous fault management systems. In addition, it allows cost effective remote maintenance system with highly convenient manageability. We implemented the prototype system of our proposed architecture and evaluated the performance on the query response time of home resources and relations in a real environment. Results showed that it has acceptable performance for navigating or control of home information and excellent improvements in terms of relation based search. We anticipate that the proposed system will bring the huge benefits not only to the consumers, home network service providers but also to the home network maintenance companies in terms of ease of management, and diagnostic effectiveness.

Various home network middleware such as HAVi, LnCP, LonWorks, and UPnP have been designed. They coexist because one middleware cannot support diverse requests of services and devices. This circumstance creates an interoperability problem among devices based on various types of home network middleware. The Universal Middleware Bridge system is designed and implemented to solve this interoperability problem using a device conversion mechanism and a message translation mechanism among the middleware. These conversion mechanisms make it possible for devices to distinguish and control other devices connected to different middleware networks in the Universal Middleware Bridge system. These mechanisms also easily support new device and middleware by adding some XML files.

Recently, high-speed powerline communication gets great attention as the home network backbone for multimedia services because of the low cost and QoS support. Since a home network is mixed with various types of networks, the high-speed powerline communication is often connected with non-QoS networks such as Ethernet. Then it is very difficult to provide end-to-end QoS for multimedia services in the home network environments since traffics are often transported to Ethernet. In this paper we deal with some QoS issues at the bridge for multimedia service when it connects high-speed powerline communication and Ethernet. Also, we introduce a QoS support Ethernet/high-speed powerline communication bridge system and shows some experimental results in this paper.

This paper presents the IEEE 1394/UPnP software bridge for representing legacy IEEE 1394 devices to UPnP devices. UPnP devices must provide SSDP discovery, SOAP control, and GENA event processes. To represent the legacy IEEE1394 devices to UPnP devices, there have to be the IEEE 1394/UPnP software bridge to provide those functionalities on behalf of IEEE 1394 devices. The bridge can provide additional functions such as A/V data transferring with format converting between IEEE 1394 and UPnP devices. With those functionalities, the bridge makes UPnP control points recognize IEEE 1394 devices as UPnP devices, and makes possible exchange the A/V data between IEEE 1394 legacy devices and normal UPnP devices. Based on the general structure of the bridge, it can be easily extended to support a new IEEE 1394 device type.