• The Transactions of the Korean Institute of Power Electronics
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• v.8 no.2
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• pp.151-164
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• 2003

In this paper, induction motor drives with low switching acoustic noise based on the 2 phase modulated RLL(Random Lead-Lag) PWM is proposed and implemented. The proposed switching method is much bettor than 3 phase modulated RLL-PWM from the standpoint of the broadening effect of the acoustic noise spectrum. Along with the randomization of PWM Pulses, SVM(Space Vector Modulation) is executed in the TMS320C31 DSP(Digital Signal Processor). To verify the validity of the proposed RPWM(Random PWM), the experimental study was tried. The experimental results show that the performance of the proposed method and the 3 phase center-aligned SVM / conventional RLL-PWM are nearly the same from the viewpoint of the constant v/f centrel. But, in case of the proposed 2 phase modulated RLL-PWM, the spectrum characteristics of the voltage and the switching acoustic noise are shown to have better broadening effect than 3 phase modulated one.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.9
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• pp.2074-2079
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• 1997

Much recent work has been done in the two related areas of source coding for data compression, and channel coding for data storage, respectively. We propose two (0, k) run-lengh limited(RLL) data compression codes for the storage that combine source and channel coding. It was shown that the propsoed codes approach the maximum code rate of (0, k) code as k increase. Thus, the overall code rate of storage system can be increased by using the combined source/channel coding as compared to the conventional 8/9 code which is popular in hard drive systems Functhermore, one can also reduce the complexity of modulation coding procedure by using already RLL constrained data.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.10B
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• pp.1453-1457
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• 2001

본 논문에서는 DC-제거 가능한 (2, 15) 런-길이 제한(RLL) 코드와 이 코드를 이용한 고밀도 광 기록을 위한 고효율의 성능을 나타내는 코딩 방법을 제안한다. 이 방법은 8/16의 코드율을 갖는 가족의 EFMPlus 코드와 비교하여 k-구속 조건이 다른 런-길이 파라미터를 가지고 있으나 EFM 코드에 비해 최소 6%에서 최대 10% 이상 높은 정보 밀도를 갖고 있어 고밀도 광 기록 시스템에 적용이 가능하다. 모의 실험을 통해, 코드율이 8/16에서는 EFMPlus 코드와 거의 유사한 성능을 보임을 확인했다.

• Journal of Institute of Control, Robotics and Systems
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• v.2 no.1
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• pp.53-59
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• 1996

An automatic verification method has been studied to determine the safety and operability of programmable logic controller (PLC) based systems. For the systematic and efficient verification, we have developed a conversion method from relay ladder logic (RLL) to the verification system description. RLL is a common representation used to document PLC programs for the sequential logic of the system such as the safety interlocks and the startup/shutdown procedures. Once the modules are developed, complex RLLs can be represented by the combination of modules. As a result we can verify complex PLC systems using the verification method including RLL modules. The developed modules are used to verify alarm systems and show that the method is valid.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.735-738
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• 1998

To develop an effective virtual prototyping methodology for the PLC(Programmable Logic Controller) based real-time systems, a conversion algorithm from RLL(Relay Ladder Logic) to statechart is presented in this paper. The RLL is the main programming language to represent the operation of the PLC, and the statechart is the most widely used tool in the field of virtual prototyping in order to represent the behaviour of real-time systems. A virtual prototyping for an example case is implemened to evaluate the benefit of the proposed algorithm.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.8
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• pp.1128-1136
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• 1989

The power spectral densities of run-length-limited(RLL) minimum-bandwidth(MB) line codes are obtained for some values of the zero probability of input data. They can be obtianed by implementing a computer program for the G.L. Cariolaro's algorithm. Using the program we calculate the power spectra of the known RLL MB line codes, such as VDB5, TIB5, VMDB5, RMD35, DRMD35, RMD45, and RMD33, and compare the characteristics of them. Specially, the relationship between eye widths and power spectra is analyzed.

• Journal of Chest Surgery
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• v.33 no.4
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• pp.324-328
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• 2000

Multiple primary lung cancer is not common and classified as a synchronous primary lung cancer and a metachronous primary lung cancer. We experienced one case of the triple synchronous primary lung cancer of different cell types. We conducted right pneumonectomy for preoperative diagnosed neuronendocrine tumor of the RUL and adenocarcinoma of the RLL. Pathologic examination revealed the carcinoid tumor of RUL bronchus, the squamous carcinoma of the RML and the adenocarcinoma of the RLL.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.7
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• pp.1559-1565
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• 1997

A new multitrack RLL codes with immunity to intertrack interference (ITI) is proposed. This code takes aim at a high density storage channels by reducing the track width and/or guard bands between tracks since it prevents transition in neighboring tracks at the same time epoch. The capacities of the codes are found for each maximum and minimum constraint pair.

• Journal of Chest Surgery
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• v.22 no.2
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• pp.308-314
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• 1989

Pulmonary sequestration is a congenital malformation characterized by an area of embryonic lung tissue that derives its blood supply from an anomalous systemic artery. Two forms recognized: extralobar and intralobar. Extralobar form is a very rare congenital malformation, usually located in the lower chest, and may be found in newborn infants at the time a congenital diaphragmatic hernia is repaired. Large sequestrated segments may be cause acute respiratory distress in the neonate. The condition is asymptomatic in 15 per cent of patients. This report presents two cases of pulmonary sequestration which misdiagnosed a superior mediastinal tumor and a benign lung tumor. First case was 30-year-old male patient and chief complaints were dyspnea, dry cough and right chest pain. Chest X-ray showed a homogenous increased density of smooth margin at the right superior mediastinal area and suggested a benign mediastinal tumor. And so explothoracotomy was made without other special studies. Second case was 28-year-old male patient. One month ago, he had tracheostomy and right closed thoracostomy due to massive hemoptysis and spontaneous hemothorax. Chest X-ray showed a benign cystic lesion at RLL area. At the time of operation, in first case, a mass of adult fist size was placed medial to the right upper lobe and densely adhesive to trachea, SVC and esophagus. Blood supply of the mass was bronchial arteries of trachea and RUL bronchus and drained to SVC and azygos vein through anomalous systemic veins. There was no bronchial communication on Frozen biopsy. In 2nd case, large cystic lesion contained old blood hematoma was located in RLL and anomalous blood vessel from thoracic aorta was drained to posterior segment of RLL. In operation field, intralobar pulmonary sequestration was diagnosed, and RLL lobectomy was carried out.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.2C
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• pp.175-180
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• 2009

When we apply the LDPC code for high density optical storage channel, it is necessary to make an algorithm that the modulation code decoder must feed the LDPC decoder soft-valued information because LDPC decoder exploits soft values using the soft input. Therefore, we propose the soft-input soft-output run-length limited 17PP decoding algorithm and compare performance of LDPC codes. Consequently, we found that the proposed soft-input soft-output decoding algorithm using 17PP is 0.8dB better than the soft-input soft-output decoding algorithm using (1, 7) RLL.