• Journal of Semiconductor Engineering
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• v.2 no.3
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• pp.136-141
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• 2021

This paper analyzes the tree expansion for multiple-input multiple-output (MIMO) detection in the viewpoint of hardware implementation. The tree expansion is to calculate path metrics of child nodes performed in every visit to a node while traversing the detection tree. Accordingly, the tree-expansion unit (TEU), which is responsible for such a task, has been an essential component in a MIMO detector. Despite the paramount importance, the analyses on the TEUs in the literature are not thorough enough. Accordingly, we further investigate the hardware complexity of the TEUs to suggest a guideline for selection. In this paper, we focus on a pair of major ways to implement the TEU: 1) a full parallel realization; 2) a transformation of the formulae followed by common subexpression elimination (CSE). For a logical comparison, the numbers of multipliers and adders are first enumerated. To evaluate them in a more practical manner, the TEUs are implemented in a 65-nm CMOS process, and their propagation delays, gate counts, and power consumptions were measured explicitly. Considering the target specification of a MIMO system and the implementation results comprehensively, one can choose which architecture to adopt in realizing a detector.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.5
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• pp.473-483
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• 2021

This study's fundamental purpose is to examine the personality factors of business school faculty members in job satisfaction and job performance. Results show the significant impact of multicultural faculty members' job performance in a diverse environment in the Business schools of Karachi. The data is collected through the multi questionnaires from the various teaching, non-teaching staff, and students of private business schools of Karachi in Pakistan. The data has been tested through the Jamovi-by-medmod, and the regression model is to scrutinize and find the effect dependent variables to mediation. Simultaneously, results are calculated by mediation estimates and path estimates through the medmod technic and regression test from data. It provides a comprehensive insight into various factors such as personality traits, self-efficiency, Psychological diversity climate, self-esteem, and human resource management practices. These are the primary evaluated factors that affect multicultural faculty members' job satisfaction and job performance. However, results show a positive relationship between diversity climate and job performance, which mediates by job satisfaction. Similarly, personality traits show a positive relationship with job performance that mediates by job satisfaction. Correspondingly, self-esteem spectacles are a positive inter-relationship with job performance which is mediated by job satisfaction.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.13 no.4
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• pp.99-107
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• 2003

In this paper we propose an international cross certification model using cross certificate. We propose a new model by analyzing and solving current problems of the National PKI. We recommend a certificate profile, design a directory schema, and propose a method to access PSE(personal security environment) using PKCS＃11, which gives the expansibility and convenience. Finally, we propose a certificate path verification method using RFC 3280 and show how to get the certificate chain by using the trust anchor. This model is recommended to the detailed level of specification for the interoperability of each country's PKI.

• The Journal of Korea Robotics Society
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• v.16 no.4
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• pp.327-335
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• 2021

In this paper, we propose an embedded robot system based on "ROS2 on Yocto" that can support various robots. We developed a lightweight OS based on the Yocto Project as a next-generation robot platform targeting cloud robotics. Yocto Project was adopted for portability and scalability in both software and hardware, and ROS2 was adopted and optimized considering a low specification embedded hardware system. We developed SLAM, navigation, path planning, and motion for the proposed robot system validation. For verification of software packages, we applied it to home cleaning robot and indoor delivery robot that were already commercialized by LG Electronics and verified they can do autonomous driving, obstacle recognition, and avoidance driving. Memory usage and network I/O have been improved by applying the binary launch method based on shell and mmap application as opposed to the conventional Python method. Finally, we verified the possibility of mass production and commercialization of the proposed system through performance evaluation from CPU and memory perspective.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.314-319
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• 2002

The Automation and Control Group at the University of Brasilia is developing an automatic welding station based on an industrial robot and a controllable welding machine. Several techniques were applied in order to improve the quality of the welding joints. This paper deals with the implementation of a laser-based computer vision system to guide the robotic manipulator during the welding process. Currently the robot is taught to follow a prescribed trajectory which is recorded a repeated over and over relying on the repeatability specification from the robot manufacturer. The objective of the computer vision system is monitoring the actual trajectory followed by the welding torch and to evaluate deviations from the desired trajectory. The position errors then being transfer to a control algorithm in order to actuate the robotic manipulator and cancel the trajectory errors. The computer vision systems consists of a CCD camera attached to the welding torch, a laser emitting diode circuit, a PC computer-based frame grabber card, and a computer vision algorithm. The laser circuit establishes a sharp luminous reference line which images are captured through the video camera. The raw image data is then digitized and stored in the frame grabber card for further processing using specifically written algorithms. These image-processing algorithms give the actual welding path, the relative position between the pieces and the required corrections. Two case studies are considered: the first is the joining of two flat metal pieces; and the second is concerned with joining a cylindrical-shape piece to a flat surface. An implementation of this computer vision system using parallel computer processing is being studied.

• ETRI Journal
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• v.46 no.3
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• pp.485-500
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• 2024

A hardware architecture is presented to decode (N, K) polar codes based on a low-density parity-check code-like decoding method. By applying suitable pruning techniques to the dense graph of the polar code, the decoder architectures are optimized using fewer check nodes (CN) and variable nodes (VN). Pipelining is introduced in the CN and VN architectures, reducing the critical path delay. Latency is reduced further by a fully parallelized, single-stage architecture compared with the log N stages in the conventional belief propagation (BP) decoder. The designed decoder for short-to-intermediate code lengths was implemented using the Virtex-7 field-programmable gate array (FPGA). It achieved a throughput of 2.44 Gbps, which is four times and 1.4 times higher than those of the fast-simplified successive cancellation and combinational decoders, respectively. The proposed decoder for the (1024, 512) polar code yielded a negligible bit error rate of 10^-4 at 2.7 E_b/N_o (dB). It converged faster than the BP decoding scheme on a dense parity-check matrix. Moreover, the proposed decoder is also implemented using the Xilinx ultra-scale FPGA and verified with the fifth generation new radio physical downlink control channel specification. The superior error-correcting performance and better hardware efficiency makes our decoder a suitable alternative to the successive cancellation list decoders used in 5G wireless communication.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.5
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• pp.56-63
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• 2009

The IEEE 802.11 standard has been used for wireless data networks such as wireless LAN, ad-hoc network, and vehicular ad-hoc network. Thus, the performance analysis of the IEEE 802.11 specification has been one of the hottest issues for network optimization and resource management. Most of the analysis studies were performed in a data plane of the IEEE 802.11 unicast. However, IEEE 802.11 broadcast is widely used for topology management, path management, and data dissemination. Thus, it is important to understand the performance of the broadcast scheme for the design of efficient wireless data network. In this contort, we analyze the IEEE 802.11 broadcast scheme in terms of the broadcast frame reception probability according to the distance from a sending node. Unlike the other works, our analysis framework includes not only the system parameters of the IEEE 802.11 specification such as transmission range, data rate, minimum contention window but also the networking environments such as the number of nodes, network load, and the radio propagation environments. Therefore, our analysis framework is expected to be used for the development of protocols and algorithms in a dynamic wireless data network.

• The KIPS Transactions:PartA
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• v.11A no.4
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• pp.277-284
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• 2004

This paper presents a facial expression control method of 3D avatar that enables the user to select a sequence of facial frames from the facial expression space, whose level of details the user can select hierarchically. Our system creates the facial expression spare from about 2,400 captured facial frames. But because there are too many facial expressions to select from, the user faces difficulty in navigating the space. So, we visualize the space hierarchically. To partition the space into a hierarchy of subspaces, we use fuzzy clustering. In the beginning, the system creates about 11 clusters from the space of 2,400 facial expressions. The cluster centers are displayed on 2D screen and are used as candidate key frames for key frame animation. When the user zooms in (zoom is discrete), it means that the user wants to see mort details. So, the system creates more clusters for the new level of zoom-in. Every time the level of zoom-in increases, the system doubles the number of clusters. The user selects new key frames along the navigation path of the previous level. At the maximum zoom-in, the user completes facial expression control specification. At the maximum, the user can go back to previous level by zooming out, and update the navigation path. We let users use the system to control facial expression of 3D avatar, and evaluate the system based on the results.

• Journal of Broadcast Engineering
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• v.19 no.5
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• pp.726-735
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• 2014

In accordance with 4K UHD(Ultra High Definition) LCD television's higher resolution and data expansion, LCD TV had to face problems such as increasing numbers of cables and tangible skews problems among cables. The V-by-One HS is a new interface technology in the path between the image processing IC and timing control (TCON) board. The variable speed from 600 Mbps to 3.75 Gbps effectively meets the requirements of various different pixel rates. In this paper, we use the V-by-One HS interface to illustrate our proposed simulation method of frequency resonance mode and PCB design approach to model the effects of signal integrity for high speed video signal using an IBIS models.

• Journal of KIISE:Computing Practices and Letters
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• v.6 no.5
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• pp.536-542
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• 2000

This paper proposes Visual Script Language which can direct a type of motion to 3D human model and create by dragging gesture like as we can express a certain meaning with hand gestures. Traditional motion control technique of articulated figures such as human needs a complex task that draws on highly developed human skills. So it will reduce the amount of motion specification to provide the motion control method that allow users to describe characters' motion at the higher level abstraction. Visual script is the visual gestures to direct various human motions, so users can express the spatial attributes of a motion such as the path of moving with high-level concepts if they use visual script. And we can show that it is possible to control the motion of human model directly and intuitively by development of 3D human motion control system based on visual script.