SAW Filter Transmission Characteristics Design with Genetic Algorithm

Park, Kyu­-Chil,Kim, Seok­-Jae The Korea Institute of Information and Commucation 2003 한국정보통신학회논문지 Vol.7 No.8

SAW(Surface Acoustic Wave) 필터는 탄성표면파를 응용한 신호처리 기능 소자로, 각종 통신 기기의 고주파 회로의 대역 통과 필터로 이용된다. 기본적인 구성은 압전체 기판의 표면에 전기 신호와 표면파를 서로 교환하기 위한 입/출력 IDT(interdigital transducer) 한 쌍으로 이루어진다. 그 주파수 특성은 입/출력 IDT의 간격과 각각의 길이에 의해 결정되어지며, 대역 통과 필터의 특성을 지닌다. 본 논문은 이런 SAW 필터의 수치 설계 방법론에 관한 것이다. 입력 IDT의 전극의 길이를 변수로 정하고, 중심 주파수, 통과 대역의 폭과 정지 대역의 감소치가 주어졌을 때 적응/최적화 알고리즘을 이용하며 필터를 설계한다. 설계하고자 하는 필터 특성과 임의의 시간에 만들어진 필터와의 오차를 목적 함수로 정하고, 이 목적 함수를 최소화하는 것으로 필터의 설계가 가능하게 된다. SAW 필터의 계산 모델로는 델타 함수 모델과 등가 회로 모델을 사용하였으며, 최적화 알고리즘으로는 유전자 알고리즘을 사용하였다. The SAW device is extensively used as a electro$.$mechanical band­pass filter in which a two­pairs of interdigital transducers are provided over the surface of the piezoelectric substrate. For the design requirement, the central frequency and the bandwidth of the passband, and the attenuation level of the stopband region are specified. The configuration is made so as to satisfy the specification given. The central frequency is mainly determined by the distance between the pair of the finger electrodes. The design is considered as an optimization problem with which the error norm, the distance between the desired characteristics and the calculated for a given model is to be minimized. The delta function model and the electrical equivalent circuit model are utilized to represent the SAW filter characteristics. Genetic algorithm is used for optimization in which apodization of the transducer fingers is chosen as a design variable.

위치관리를 위한 단말기 페이징 기법의 성능 분석

김규칠,최창열,김용석 江原大學校 産業技術硏究所 2001 産業技術硏究 Vol.21 No.B

Terminal paging is the process of determining the exact location of a particular mobile terminal. The paging cost is related to the number of paging cycles and the number of cells being polled by each cycle. In this paper, we first analyze the performance of various terminal paging strategies in terms of the number of polling cycles and the number of polling signals. Then we present a paging scheme which combines Shortest-Distance-First with movement history list. Simulation results show that the proposed paging scheme reduces the number of polling signals as well as the number of polling cycle.

Cd(Ⅱ) 폴라로그람의 異常波에 關한 硏究

崔七男,朴聖珪,丁梧鎭,문경국 조선대학교 기초과학연구소 1984 自然科學硏究 Vol.7 No.1

pH 6.0∼12.0 範圍에서 0.15M 타르타르 酸鹽支持溶液 속에서 Cd(Ⅱ) Polarogram을 25℃에서 二段還元波를 調査한 결과 pH8.2部分 까지는 限界電流 및 半波電位값이 一定하며 한편 같은 濃度의 窒酸鹽 支持溶液을 사용하였을 때에 比하여 一段還元波의 半波電位값은 0.03volt 陰의 電位값으로 移動하고, 限界電流 값은 21% 減少되었다. pH8.2 部分 以上부터 限界電流 값이 急激하게 增加하다가 pH8.9 以上부터는 다시 急激하게 減少하는 現象을 보여 주었다. 한편 pH8.2 以上부터는 半波電位가 pH11.0에서는 -1.37volt로 되었다. 可能한 電極反應을 假定하여, pH11.0에 이르기까지의 還元波移動의 原因을 檢討하였다. The second reduction waves of the polarogram of Cd(Ⅱ) in 0.15M sodium tartrate solution were investigated in the range of pH from 6.0 to 12.0 at 25 C. Up to pH 8.2, the limiting current and the half wave potential were found to be constant, and when compared with the nitrate solution equal to the concentration of sodium tartrate, the limiting current of the first reduction wave has been decrease 21% and the half wave potential of the first reduction wave shifted by -0.03 volt. The values of limiting current were sharply increased above pH 8.2, and maximum value was obtained at pH 9.8. The half wave potentials were gradually proceeded in negative direction with increasing pH and the half wave potential of -1.37 volt was obtained at the pH 11.0. Suggesting possible mechanisms of electrode reactions, the anomalous behavior of reduction waves of Cd(Ⅱ) in sodium tartrate solution up to pH 11.0 was discussed.

肉類資源의 開發을 위한 雜肉의 處理 및 加工에 관한 硏究

黃七星,韓錫絃,崔炳圭 건국대학교 1977 學術誌 Vol.21 No.2

This experiments were carried out to study on the effect of the processing and manufacture far cultivating meat resources. The only Korean native goats and rabbits were slaughtered and the hue weight, carcass and percentages of the various organs were measured to determined the edible meat productivity. Pork, Korean native goat meat and rabbit meat sausages were made in general process and each samples of treatment lots were analyzed on the chemical compositions by routine analysis. The experimental samples ware instituted in three groups of pork. Korean native goat meat, and rabbit meat sausage and for 50days of complete preservation stages were divided to 10 parts on a fixed date at regular intervals of 10 days in a refrigerator at 4-5℃ Temperature, Each samples were examined on the tenderness, moistureness, PH. value. On the other hand, just each samples were carried out too microbiogical investigation at regular intervals of 10days. The results obtained by these studies were summarized as follows. 1 The average live weight of Korean native male goat of 22.6kg showed average dressing percentage 40.23 percent and edible meat percent 58.74 percent 2 The dressing percent of rabbit was 49.15% on the average live weight (1976.32g) of male rabbits and 49.82% on the average live weight (1928.82g) of female rabbits and total edible meat percentage was 55.25% irrespectively of sex. 3 As to the major chemical composition of longis nimus dorisi muscle, crude protein was determined at 18.40 percent of pork, 23.57 percent of rabbit meat and 23.39 percent of Korean native goat meat, but on that the day after processing were decreased at level 12.51 percent of pork sausage, 14.98 percent of rabbit meat sausage and 14.75 percent of Korean native goat sausage samples. Penetration-t values on the results of the tenderness test had no significant range statistically of 5 percent level in the each treatment lots and of course on the all preservation stage samples. 5 The breadth of PH change from immediately after sausage processing to binal preservation stage were Korean native goat meat PH 6.24-6.42, Pork PH 6.40-0.43 and rabbit meat sausage PH 6.28-6.52. 6 Change of PH and moistureness was positive correlation and recognized regression equation y 53.29 2.0595x of Korean native goat, y 49,94 22.7373x of pork and y 53.94 0.2821 of rabbit meat sausage but no significant statistically of 5 percent level at t-test. 7 Result of microbiological investigation from immediately after sausage processing to final preservation stage were counted 1.4 10 4.1 10 of pork, 1.1 10 2.5 10 of Korean native goat, and 1.6 10 4.8 10 numbers of rabbit meat sausage samples. 8 The number of psychrophilic bacterial showed a tendency of increase accompany progress of a preservation and 2.0 10 7.2 10 of pork, 6.7-10 4.6 10 of Korean native goat and 7.0 10 7.7 10 numbers of rabbit meat sausage samples. 9 Z. Coli bacteria were not counted wholly through all preservation periods.

데이터 마이닝을 이용한 CRM 연구

김규곤,이동철,이병칠 동의대학교 경제경영전략연구소 2003 經濟經營硏究 Vol.1 No.1

Recently, enterprises were concerned about the relationship marketing for getting a powerful competitiveness, as the managerial environments were changing from mass marketing in the 1970s to recognizing the importance of customer in a turbulent market in the mid-1980s. There appeared CRM(customer relationship management) as an important method for satisfying the customer. Especially, it was important issue for companies the keeping of existing customer for long time in a competitive environment. In this paper, it is used general multivariate analysis methods and data mining analysis methods such as discriminant analysis, logit model, decision tree analysis, and neural networks. Also, it is tried to find the most efficient model of the data mining analysis in insurance CRM. In addition, it is analyzed and verified the most agreeable model of the data mining estimation about the secession of customers in an insurance company. Finally, effective marketing strategies and some tasks on this issue hereafter based on the results were suggested.

「작물별ㆍ재배유형별 표준시비량과 시비추천량」프로그램

정호근,조재규,최칠구,김사균 한국농업정보과학회 2000 농업정보과학 Vol.2 No.1

Generally farmers cultivate 2 or 3 crops in a year, In some cases more than 10 crops are culti-vated in a year by a farmer, These crop numbers and varieties also might be changed depending on the farmer's income based on the crop. Therefore, farmers have diHiculty in configurating the recommended for-tilizer rate for each crop. This study developed a series of user-friendly EXCEL Program to help farmers and extension specialists making decision on fertilizer rate for each crop. By using the program farmers can decide appropriate fertilizer rates based on the soil test results for each field and crop, which can improve fertilizer use efficiency. Also, this program might be useful to make a farm plan by reflerting fertilizer tost required for each field.

리눅스를 기반으로 한 홈오토메이션 서버의 구현

성한용,김규칠,방철원,김용석 江原大學校 産業技術硏究所 2002 産業技術硏究 Vol.22 No.B

It becomes common to use computers to control electronic devices and security facilities in newly constructed buildings and house. There are many home application devices in the market which can be controlled by computers. But they are expensive and managed by specialized companies. This paper is focused on personal computers which are available in most homes and can be used to control home electronic appliances and home security facilities. We implemented a home automation server based on Linux. The standard parallel port of personal computer is used to connect sensors and actuators. Therefore, the cost of the server is very low. Moreover, the server is connected to Internet and anywhere we can control and monitor the home security facilities and home automation systems.

족저에 발생한 유두상 혈관내막 증식증 1예

유화정,황규철,오칠환 대한피부과학회 2003 大韓皮膚科學會誌 Vol.41 No.7

Intravascular papillary endothelial hyperplasia(IPEH) is a relatively rare disease which is characterized by the development of endothelial-lined papillary projections. It is now believed to be a reactive process that result from organization of a thrombus. We report a case of intravascular papillary endothelial hyperplasia developed on the plantar surface of right 4th toe. (Korean J Dermatol 2003;41(7) : 982~985)

거대요관과 거대방광이 동반된 선천성 신성요붕증 1예

이은정,이규백,서정열,김향,박흥재,김영학,권칠훈,이영래 대한신장학회 2001 대한신장학회잡지 Vol.20 No.4

都市近郊 農業開發 및 觀光農園育成

金祥基,崔奎燮,權七勇,尹光默 경북대학교 1988 새마을 硏究論叢 Vol.9 No.-