• ETRI Journal
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• v.37 no.1
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• pp.54-60
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• 2015

The use of serial concatenated codes is an effective technique for alleviating the error floor phenomenon of low-density parity-check (LDPC) codes. An enhanced sum-product algorithm (SPA) for LDPC codes, which is suitable for serial concatenated codes, is proposed in this paper. The proposed algorithm minimizes the number of errors by using the failed check nodes (FCNs) in LDPC decoding. Hence, the error-correcting capability of the serial concatenated code can be improved. The number of FCNs is simply obtained by the syndrome test, which is performed during the SPA. Hence, the decoding procedure of the proposed algorithm is similar to that of the conventional algorithm. The error performance of the proposed algorithm is analyzed and compared with that of the conventional algorithm. As a result, a gain of 1.4 dB can be obtained by the proposed algorithm at a bit error rate of $10^{-8}$. In addition, the error performance of the proposed algorithm with just 30 iterations is shown to be superior to that of the conventional algorithm with 100 iterations.

• Applied Microscopy
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• v.47 no.1
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• pp.3-7
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• 2017

The automatic equipment for three-dimensional electron microscopy (3DEM) can acquire serial sections of a large sample in a relatively short time, and is especially suitable for the connectomics, which is a field related to understanding the brain structure as a whole. As many results obtained through 3DEM using automatic serial sections have been published in the field of brain research, many researchers continue to apply this technique to various samples. We reviewed the equipment for automatic serial sectioning, the block preparation method, the limitations of 3DEM, and future directions.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.9
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• pp.863-869
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• 2005

We investigated quench characteristics of superconducting elements connected in series and parallel each other. The serial and parallel connections of superconducting elements causes a difficulty in simultaneous quench due to slight difference between their critical current densities. In other to induce simultaneous quench, we fabricated four type circuits; serially connected circuit before parallel connection, the circuit connected in parallel before serial connection, serially connected circuit before parallel connection with reactors, the circuit connected in Parallel before serial connection with reactors. We confirmed that the simultaneous quenches occurred in serial and parallel connections of superconducting elements using reactors. In addition, the power burden of superconducting elements was smaller than those of serial and parallel connections of superconducting elements without reactors.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.16 no.7
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• pp.651-662
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• 1991

An improved modular multiplication algorithm for RSA type public key cryptosystem and its application to a serial communication cricuit are presented. Correction on a published fast modular multiplication algorithm is proposed and verified thru simulation. Cryptosystem for RS 232C communication protocol isdesigned and prototyped for low speed data exchange between computers. The system adops the correct algoroithm and operates successfully using a small size key.

• Proceedings of the IEEK Conference
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• 2001.06b
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• pp.337-340
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• 2001

In this Paper, 3 digit-Serial multilier With 3 digit size of 32 is proposed, which has more advantages than the 193bit serial LFSR architecture. We give a design example for the irreducible trinomials $x^{193}$＋ $x^{15＋1}$. In hardware implementations, it is often desirable to use the irreducible trinomial equations. The proposed multiplier is verified with a VHDL description using an elliptic curve addition. The measured results show that the proposed multiplier is 0.3 times smaller than the bit-serial LFSR multiplier..

• Journal of the Korean Institute of Telematics and Electronics C
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• v.35C no.1
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• pp.34-41
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• 1998

In this paper, I designed a P1394 serial bus chip as new bus interface architecture which can transmit the multimedia data at the rate of 400 Mbps and guarantee necessary bandwidth. because multimedia data become meaningless data after appropriate time, it is necessary to transfer multimedia data in real time, P1394 serial bus chip designed in this paper support isochronous transfer mode to solve this problem. Also, designed P1394 serial bus chip can transfer high quality video data or high quality audio data because it support the speed of 400 Mbps. While user must set device ID manually in previous interface such as SCSI, device ID is automatically determined if user connect each node with designed P1394 serial bus cable and power on. To design this chip, I verified the behavioral of the entrire system and synthesized layout. Also, I did layout the analog blocks and blocks which must be optimized in full custom.

• International Journal of Naval Architecture and Ocean Engineering
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• v.8 no.5
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• pp.434-441
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• 2016

Numerical simulations of 1D Burgers equation and 2D sloshing problem were carried out to study numerical discrepancy between serial and parallel computations. The numerical domain was decomposed into 2 and 4 subdomains for parallel computations with message passing interface. The numerical solution of Burgers equation disclosed that fully explicit boundary conditions used on subdomains of parallel computation was responsible for the numerical discrepancy of transient solution between serial and parallel computations. Two dimensional sloshing problems in a rectangular domain were solved using OpenFOAM. After a lapse of initial transient time sloshing patterns of water were significantly different in serial and parallel computations although the same numerical conditions were given. Based on the histograms of pressure measured at two points near the wall the statistical characteristics of numerical solution was not affected by the number of subdomains as much as the transient solution was dependent on the number of subdomains.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.4
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• pp.122-128
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• 2007

This paper represents the Input/Output (I/O) serial communication methods between overground and overhead controllers using a programmable logic controller (PLC). In general, the systems composed by overground and overhead controllers use exclusive serial communication units. This, however, has a demerit such as a high cost as well as some restrictions of the system itself. Thus, this paper suggests methods by I/O cards for data communication between overground and overhead controllers. In this system, there is no special card and it therefore has a lower cost and is more flexible than the exclusive serial communication unit.

• 한국정보통신설비학회:학술대회논문집
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• 2006.08a
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• pp.87-90
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• 2006

Nowadays, we can enjoy access to high speed network and advanced services of convergence between broadcasting and communication anywhere and anytime through a ubiquitous computing. So, now digital convergence devices come out constantly. These devices are required faster network environment for high speed data processing than before. In this paper, we describe the design of InfiniBnad network adapter, which is included two FPGA chipsets. When this adapter is installed to Digital Convergence Platform (DCP) network performance will be improved. The adapter includes 12channel serial ports for external communication and internally, uses PCI-Express bus. We have finished the test of high speed serial based network adapter through composing complete InfiniBand network and applied fabric management software. So, we have verified that it can be applied on DCP environment.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.13 no.5
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• pp.429-436
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• 1988

This paper presents a method of designing a Bit-Serial Reed-Solomon encoder using Berlekamp's Bit-Serial Multiplier Algorithm and the implementation of the (255, 223) Bit-Serial Reed-Solomon encoder using TTL logics. It is shown from these results that this encoder require substanitially less hardware than the convenional Reed-Solomon encoders.