• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.7
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• pp.3543-3557
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• 2017

Compression is a very important technique for remotely sensed hyperspectral images. The lossless compression based on the recursive least square (RLS), which eliminates hyperspectral images' redundancy using both spatial and spectral correlations, is an extremely powerful tool for this purpose, but the relatively high computational complexity limits its application to time-critical scenarios. In order to improve the computational efficiency of the algorithm, we optimize its serial version and develop a new parallel implementation on graphics processing units (GPUs). Namely, an optimized recursive least square based on optimal number of prediction bands is introduced firstly. Then we use this approach as a case study to illustrate the advantages and potential challenges of applying GPU parallel optimization principles to the considered problem. The proposed parallel method properly exploits the low-level architecture of GPUs and has been carried out using the compute unified device architecture (CUDA). The GPU parallel implementation is compared with the serial implementation on CPU. Experimental results indicate remarkable acceleration factors and real-time performance, while retaining exactly the same bit rate with regard to the serial version of the compressor.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10b
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• pp.1785-1789
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• 1991

Recently, a number of papers on adaptive control scheme of manipulators are proposed. Slotine and Li[1] showed an adaptive control scheme for robot manipulator. The controller was described in closed form. And later Niemeyer and Slotine discussed about a computational implementation of the controller in recursive form[2]. Walker proposed another adaptive control scheme which can be implemented by a recursive-form controller[4]. Closed-form description is used for the analysis or design of adaptive control systems while recursive-form realization is used for implementation of the controller. The relation between the closed-form realization and the recursive-form one seems to be inadequately referred. Hence, it makes sense to consider the relation between the closed-form description and the recursive-form one. In this paper, first, we make a simple derivation of an closed-form dynamics description of a robot arm from its recursive-form description. And then we derive the closed-form realization of Walker's scheme applied to manipulators having no kinematic loop. We clarify the difference between the Walker's scheme and Slotine's and evaluate the convergence under the controllers.

• Smart Media Journal
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• v.11 no.9
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• pp.39-46
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• 2022

The WK-recursive network proposed by Vecchia and Sanges[1] is widely used in the design and implementation of local area networks and parallel processing architectures. It provides a high degree of regularity and scalability, which conform well to a design and realization of distributed systems involving a large number of computing elements. In this paper, the routing of a message is investigated on the WK-recursive network, which is key to the performance of this network. We present an efficient shortest path algorithm on the WK-recursive network, which is simpler than Chen and Duh[2] in terms of design complexity.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.36C no.6
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• pp.37-43
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• 1999

Two-way addressing method has been proposed for efficient VLSI implementation of Euclidean calculation circuit for pipelined Reed-Solomon decoder. This new circuit is operating with single clock while exploiting maximum parallelism, and uses register addressing instead of register shifting to minimize the switching power. Logic synthesis shows the circuit with the new scheme takes 3,000 logic gates, which is about 40% reduction from the previous 5,000 gate implementation. Computer simulation also shows the power consumption is about 3mW. The previous implementation with multiple clock consumed about 5mW.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.04a
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• pp.419-423
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• 1996

These days, industrial robots are required to have high speed and high precision in doing various tasks. Recently, the adaptive control algorithms for those nonlinear robots have been developed. With spatial vector space, these adaptive algorithms including recursive implementation are simply described. Without sensing joint acceleration and computing the inversion of inertia matrix, these algorithms which include P.D. terms and feedforward terms have global tracking convergence. In this paper, the feasibility of the proposed control method is illustrated by applying to 2 DOF SCARA robot in DSP(Digital Signal Processing).

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.37 no.4
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• pp.65-71
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• 2000

Finite wordlength effect of the recursive implementation of SDFT(sliding-DFT) is analytically derived in this paper. Representation errors of the twiddle coefficients and the data registers are the two major causes of the spectral errors in the recursive implementation. The noise-to-signal ratio is analytically derived in terms of the coefficients wordlength, the data registers wordlength, and the DFT's block-length used in the computation Error dynamic equation is obtained from the recursive DFT and the probabilistic models for the coefficients error and the round-off error are introduced for the NSR derivation, The result of the NSR derivation is verified with the simulation data.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.651-654
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• 1999

This paper investigates the varying characteristics of the performance degradation resulting from the different combination of wordlength in fixed-point implementation of recursive sinusoidal transform. The performance degradation is analytically derived in the form of noise-to-signal power ratio. The best wordlength combination is shown to be the equal length distribution of the given number of bits between the transform coefficients and the data. The analysis results are also verified through the computer simulations.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2006.07a
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• pp.607-607
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• 2006

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.12
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• pp.2326-2339
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• 2011

To reduce the implementation complexity of the Vertical Bell Labs layered space-time (V-BLAST) systems with respect to the zero-forcing (ZF) criterion, a computationally efficient recursive algorithm is proposed. A fast implementation of the proposed algorithm is developed and its complexity is analyzed in detail. The proposed algorithm matches the ZF-OSIC detection well, and its three significant advantages can be demonstrated by analyses and simulations. Firstly, its speedups over the conventional ZF-OSIC with norm-based ordering, the original fast recursive algorithm (FRA) and the fastest known algorithm (FKA) in the number of flops are 1.58, 2.33 and 1.22, respectively. Secondly, a much simpler implementation than FRA and FKA can be expected. Finally, the storage requirements are lower than those of FRA and FKA. These advantages make the proposed algorithm more efficient and practical.

• The Journal of the Acoustical Society of Korea
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• v.18 no.2
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• pp.61-65
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• 1999

This paper derives a sufficient condition on the stability of recursive third-order Volterra filters based on their filter coefficients. A Volterra filter is very effective in modeling nonlinear systems with memory. However, it is well-known that the nonrecursive Volterra filter requires a large number of filter coefficients to describe a nonlinear system. For this reason, recursive Volterra filters are usually considered because the recursive implementation requires a smaller number of coefficients compared to the nonrecursive one. Unfortunately, the main problem of the recursive Volterra filters is their inherent instablility. In this paper. we present a simple condition for the output of a recursive discrete-time third-order Volterra filter to be bounded whenever the input signal to the recursive Volterra filter is bounded by a finite constant.