http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
정명덕,변건식 한국전자파학회 1996 한국전자파학회논문지 Vol.7 No.4
SO(synchronous oscillator)는 외부 인가 신호가 없을시에도 발진하는 자려발진기이며 펄스파, 정현파, 비주기적인파 등 어떠한 외부 신호에도 즉시 동기 발진하고, 출력은 일정한 동조대역폭으로 동기한다. 이러한 특성은 SO가 분주 및 체배기로 사용 가능함을 의미하며, 코히런트 디지혈 통신의 동기 문제점을 해결할 수 있을 것이며, 또 이와 같은 특성을 이용하여 DS/SS 동기적용을 위한 SO의 동기 특성을 실험을 통하여 입증하였다. The S.O(synchronous osillator) oscillates at its natural frequency without the externa applied signal. But if the external signal is applied, the S.O starts to track the external frequency which can be sinusoidal, pulsed or some other waveform. Thus, the output is synchronized with the wide range of tracking bandwidth to the external frequency. Specifically, the S.O also posses frequency division and multiplication capability. All of these indicate that the S.O can overcome the difficulties of syschronization in coherent digital communication systems. This papers proposed application of DS/SS communication with study on the synchronous properties of S.O.
정명덕,김민호,변건식 동아대학교 공과대학 부설 한국자원개발연구소 1995 硏究報告 Vol.19 No.1
For FH-SS communication, We discussed the method of indirect synthesizer in several methods. The problem of single frequency synthesizer using with PLL is a varied coefficient value of damping factor in frequency hopping time, which is caused unstable frequency. So, for stable frequency synthesizer, a coefficient of damping factor must be optimized and synthesized to be removed excessive response time. In this paper, we studied FH using with 2 loop frequency synthesizer which takes stable frequency, we made up simulator and had a good performance(real time speed).
FM을 이용한 DS/SS(FM-DS/SS) 시스템의 구현
정명덕,박지언,변건식 한국전자파학회 1998 한국전자파학회논문지 Vol.9 No.1
For implementation of FM-DS/SS system. This paper has analyzed SO(Synchronous Oscillator) being oscillated by the motivation of injected signal. Transmitter has adopted FM-DS/SS modulation method using RF output-signal of FM. Receiver is used SO to demodulation of FM-DS/SS and applied sliding correlator for synchronization of PN clock. As a result of the inspection, SO presented stable lock ability in spite of doppler apperance and proved the synchronous properties of it in the FM-DS/SS system. FM-DS /SS 시스댐 구현을 위하여, 주입되는 신호에 동기하는 주입형 SO (Synchronous Oscillator)에 대하 여 해석하였다. 송신부에서는 FM의 RF 출력 신호와 DS /SS(Direct Sequence /Spread Spectrum)을 이용하 여 FM-DS /SS 변조 방식을 채택하였으며, 수신부에서는,SO를 수신부의 PN(Pusudo Noise) 클럭 동기를 위한 슬라이딩 상관기로 사용하여 FM-DS/SS의 복조를 위한 동기부로 이용하였다. 그 결과 수신주파수가 도플러와 같은 현상에서도 안정된 동기성능을 유지하였으며, FM-DS /SS의 시스템에 적용하여 PN 동기 및 동기 특성 을 입증하였다.
동기발진기를 이용한 FM-DS/SS 통신 시스템의 구현
정명덕,변건식 한국전자파학회 1999 한국전자파학회논문지 Vol.10 No.6
FM 송수선기를 이용하여 170.120 MHz 대역의 FM - DS/SS 통신 시스댐을 구현하였다. 송선부에서는 FM 캐리어를 프리스케일러로 분주하여 확산 부호(PN)의 클럭0.329 MHz)으로 사용하였고, 변조된 FM - DS/SS 선호는 전형적인 $(sin \chi/\chi)^2$ 스펙트럼임을 알 수 있었다. 수신부에서는 역확산을 위하여 동기발진기(SO)를 응용하였다. 그리고 그림 l,그림 2. 그림 4에서와 같이 동기발진기를 슬라이딩 상관기로 구성하여 동기부에 적용한 결과, FM - DS/SS 시스댐의 수신 동기부에서 양호한 특성을 얻을 수 있었다. 본 논문에서는 FM-DS/SS 통신 시스템 구성에서 수선부 동기를 위하여 동기발진기를 사용하였다는 점이 며, 이를 뒷받침하기 위하여 동기발진기에 대한 동기 곡선과 특성들에 대한 실험 결과들을 제시하였다. In this experiment I have made FM-DS/SS system replacing 170.120 MHz by utilizing FM transmitter and receiver. In the transmitter, the result shows that the modulated FM-DS/SS signal is a typical $(sin \chi/\chi)^2$ spectrum by using the clock(1.329 MHz) of PN divided from FM carrier. In the receiver, SO(Synchronous Oscillator) was applied to despread. Like figure 1, 2, and 4 when I applied SO, which consists of sliding correlator, to synchronous a favorable properties could be obtained in the receiver of FM-DS/SS system. In this paper, I used SO in order to take synchronous in the construction of FM-DS/SS system, and to support it I presented the result of the experiment on synchronous curve and properties of OS.
백세민,정명덕 大韓成形外科學會 1989 Archives of Plastic Surgery Vol.16 No.1
Hemifacial microsomia is a descriptive term of developmental malformation affecting the first and second branchial arches, which is the second most common facial anormaly after cleft lip and palate. A wide variety of phenotypes exist, all having the common feature of asymmetric underdevelopment of the face. Most patients with hemifacial microsomia need 3 dimensional correction of facial skeleton. But if the patient is very young child, we have to consider another factor, growth. The fourth dimension, growth, adds to the complexity of the 3-dimensional defect. So detailed and careful skeletal and soft tissue analysis based on the patients age (dentition) and anatomic skeletal type is necessary. Recently early skeletal surgery including even LeFort I. maxillary osteotomy has been done as early as the age of 4 or 5. The advantage of early skeletal surgery leveling everthing in a shot operation is to let young child go to shcool looking normal and with a chance of a normal life. This is a report of our analysis and treatment of the hemifacial microsomia based on a recent 2 year experience with 27 patients. The results are summarized as follows; 1. The sex ratio was 2:7 with a greater prevalence in females. The most common age incidence was between 20 and 29 and 5 patients were in deciduous dentition. 2. 1 case was bilateral type, and left side facial deformity was remarkably more common than right (17:10). Of 27 patients, 9 had ear deformity (33%) and 1 had cranial nerve involvement. 3. 25 of 27 patients had operative procedures to correct the skeletal deformities. 13 of 14 skeletal type I patients, mean age of 25.4 years, 10 of 11 type Ⅱ patients, mean 17.1 years. All of 2 type Ⅲ patients, mean age 12 years. 4. Of 20 patients in permanent dentition, 13 had type I of 4 patients in deciduous dentition, 3 had type Ⅱ mandible. I in mixed dentition had type Ⅱ mandible. 5. 25 patients have had surgical correction. Contour restoration operations (type 1) were performed in 8 patients, LeFort 1½ maxillary osteotomies and bilateral ramus operations (type 2) in 12 patients, unilateral temporomandibular joint constructions in 2 patients, LeFort 1½ osieotomy and unilateral temporomandibular joint construction in 1 patient, and LeFort 1½ osteotomies and unilateral temporomandibular joint constructions and contralateral ramus operations in 2 patients. 6. There were no major complications. Only one of 25 patients had minor complication, superficial infection necessitating drainage and irrigation with antibiotics solution.