• Journal of Power Electronics
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• v.17 no.3
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• pp.664-673
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• 2017

With the development of multilevel converters, cascaded single-phase H-bridge rectifiers (CHBRs) has become widely adopted in high-voltage high-power applications. In this study, sequence pulse modulation (SPM) is proposed for CHBRs. SPM is designed to balance the dc-link voltage and maintain the smooth changes of switch states. In contrast to phase disposition modulation, SPM balances the dc-link voltage even after removing the load of one submodule. The operation principle of SPM is deduced, and the unbalance degree of SPM is analyzed. All the proposed approaches are experimentally verified through a prototype of a four-module (nine-level) CHBR. Conclusions are drawn in accordance with the results of SPM and its imbalance degree analysis.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.9A
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• pp.2141-2152
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• 1998

In this paper, we design and implement an indoor wireless modem using small signal of ISM band regulation, which can tranceive reliable data streams. We use direct sequence spead spectrum (DS-SS) signaling with synchronous BPSK and QPSK modulation, convolutional coding with viterbi decoding. The radio frequency module uses frequency devision duplexing in 900 MHz band, and the digital module is implemented with FPGAs for the purpose fo ASIC design. The perfomrance of our own acquistion and tracking circuit consisting digital matched filter and decision logic is proved by experiments, and the possibility of file transfer at indoor environment with the entrie system that the modem is connected the PC through RS-232C port is verified.

• Journal of IKEEE
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• v.7 no.2 s.13
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• pp.166-171
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• 2003

In this paper, we propose a minimal power data path allocation algorithm for low power circuit design. The proposed algorithm minimizes switching activity for input variables in scheduled CDFG. Allocations are further divided into the tasks of register allocation and module allocation. The register allocation algorithm execute that it eliminate spurious switching activity in functional unit and minimize the numbers of multiplexer. Also, resource allocation method selects a sequence of operations for a module such that the switching activity is reduced. Therefore, the algorithm executes to minimize the switching activity of input values, sequence of operations and number of multiplexer. Experimental results using benchmarks show that power is reduction effect from 13% to 17% power consumption, when compared with the Genesis-lp high-level synthesis system.

• Proceedings of the IEEK Conference
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• 2003.07a
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• pp.214-217
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• 2003

In this paper, we deal with implementing design for a correlator access code generator module which they are used for setting up a connection between units, a packet decision, a clock syncronization, by FPGA. The orrelator module which is composed of the Wallace Tree's CSA and threshold value decision device decides useful a packet and syncronizes a clock, after it correlates an input signal of 1 Mbps transmission rate by a sliding window. An access code generator module which is composed of a BCH (Bose-Chadhuri-Hocquenghem) cyclic encoder and control device was designed according as a four steps' generation process proposed in the bluetooth standard. The pseudo random sequence which solves syncronization problem saved a voluntary device Proposed the module was designed by VHDL. An simulation and test are inspected by Xilinx FPGA.

• Korean Journal of Computational Design and Engineering
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• v.5 no.3
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• pp.255-262
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• 2000

A computer-aided process planning (CAPP) system for rotationally symmetric deep drawing products has been developed. The application for non-axisymmetric components, however, has not been reported yet. Therefore, this study investigates process sequence design in deep drawing process and constructs an expert system of process planning for non-axisymmetric motor frame products with elliptical shape. The system developed consists of four modules. The first one is recognition of shape module to recognize the products. The second one is a 3-D modeling module to calculate surface area for non-axisymmetric products. The third one is a blank design module that creates an oval-shaped blank with the identical surface area. The forth one is a process planning module based on production rules that play the best important role in an expert system for manufacturing. The production rules are generated and upgraded by interviewing with field engineers. The constructed system using AutoLISP language under the AutoCAD environment is baled on the knowledge base system which is involved a lot of expert's technology. Results of this system will be provide effective aids to the designer and engineer in this field.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.7
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• pp.3433-3446
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• 2019

Aiming at the high complexity of traditional single-channel demodulation algorithm for PCMA signals, a new demodulation algorithm based on neural network is proposed to reduce the complexity of demodulation in the system of non-cooperative PCMA communication. The demodulation network is trained in this paper, which combines the preprocessing module and decision module. Firstly, the preprocessing module is used to estimate the initial parameters, and the auxiliary signals are obtained by using the information of frequency offset estimation. Then, the time-frequency characteristic data of auxiliary signals are obtained, which is taken as the input data of the neural network to be trained. Finally, the decision module is used to output the demodulated bit sequence. Compared with traditional single-channel demodulation algorithms, the proposed algorithm does not need to go through all the possible values of transmit symbol pairs, which greatly reduces the complexity of demodulation. The simulation results show that the trained neural network can greatly extract the time-frequency characteristics of PCMA signals. The performance of the proposed algorithm is similar to that of PSP algorithm, but the complexity of demodulation can be greatly reduced through the proposed algorithm.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.3
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• pp.768-776
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• 1994

This paper describes computer-aided forging design for rib/web shaped parts. In manufacturing a part by means of forging process, the first step is to design the forging. This is done by modifying the given machined part geometry according to the requirements of the forging process. Traditionally, this is done by experienced forging designers using empirical forging design guidelines. Generally, it would be neither possible nor practical to develop a system which encompasses the design of all types of forgings. Accordingly, forging design can be simplified by considering critical two dimensional cross sections of the machined part geometry. This system is composed of three modules(process variable decision module, forging design module and redesign module) and each module is carried out in regular sequence. In the process variable decision module, first of all, the undercut is checked and modified, and then deep recesses and holes difficult to forge are eliminated. Also parting line, forging plane, forging plan view area, forging weight and maximum size(maximum height or width)are determined. In the forging design module, the magnitude of various allowances, draft angle, minimum web thickness, corner and fillet radius are determined and then geometry modification is performed. Finally, since the design rules and databases used in this system are based on parameters of the forging geometry, such as the trimmed forging plan area, forging weight, forging maxmum size, plausible estimates need to be made for these parameters. Therefore, in the re-design module, the design process is iterated until a satisfactory forging is obtained.

• Korean Journal of Microbiology
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• v.47 no.3
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• pp.188-193
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• 2011

As a specific and effective therapeutic genetic material against hepatitis C virus (HCV) multiplication, HCV internal ribosome entry site (IRES)-targeting hammerhead ribozyme which activity is allosterically regulated by HCV regulatory protein, NS5B RNA replicase, was constructed. The allosteric ribozyme was composed of sequence of RNA aptamer to HCV NS5B, communication module sequence which can transfer structural transition for inducing ribozyme activity upon binding NS5B to the aptamer, and sequence of ribozyme targeting +382 nucleotide of HCV IRES. With real-time PCR analysis, the ribozyme was found to efficiently inhibit HCV replicon replication in cells. Of note, the allosteric ribozyme was shown to inhibit HCV replicon replication more efficiently than either HCV genome-targeting ribozyme or NS5B aptamer only. This allosteric ribozyme can be used as a lead genetic agent for the specific and effective suppression of HCV replication.

• Journal of the Institute of Convergence Signal Processing
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• v.2 no.1
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• pp.1-11
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• 2001

This paper presents a learning-based approach for the construction of license Plate recognition system. The system consist of three modules. They are respectively, car detection module, license plate recognition module and recognition module. Car detection module detects a car in the given image sequence obtained from the camera with simple color-based approach. Segmentation module extracts the license plate in detect car image using neural network as filters for analyzing the color and texture properties of license plate. Recognition module then reads characters in detected license plate with support vector machine (SVM)-based characters recognizer. The system has been tested from parking lot and tollgate, etc. and have show the following performances on average: Car detect rate 100%, segmentation rate 97.5%, and character recognition rate about 97.2%. Overall system performances is 94.7% and processing time is one sec. Then our propose system does well using real world.

• Korean Journal of Microbiology
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• v.44 no.3
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• pp.186-192
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• 2008

For the development of specific and effective basic genetic materials to inhibit replication of hepatitis C virus (HCV), HCV genome-targeting trans-splicing aptazyme, which activity is allosterically regulated by a specific ligand, was developed. The aptazyme was designed to be comprised of sequence of RNA aptamer to the ligand, communication module sequence which can transfer structural transition for inducing ribozyme activity upon binding the ligand to the aptamer, and trans-splicing ribozyme targeting +199 nt of HCV IRES. Especially, when the aptamer and the communication module was inserted at both P6 and P8 catalytic domain of the specific ribozyme, allosteric activity of the aptazyme was the most induced. The aptazyme was shown to induce activity of trans-splicing reaction specifically and efficiently only in the presence of the specific ligand, but neither in the absence of any ligand nor in the presence of control ligand. This aptazyme can be used as a specific and effective genetic agent against HCV, and a tool for the isolation of anti-HCV lead compounds.