• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.613-617
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• 2002

The ceramic filters were developed using technology similar to that of quartz crystal and electromechanical filter. However, the key to this development involved the theoretical analysis of vibration modes and material improvements of piezoelectric ceramics. The primary application of ceramic filters has been for consumer-market use. Accordingly, a major emhpasis has involved mass production technology, leading to low-priced devices. A typical ceramic filter includes monolithic resonators and capacitors packaged in unique configurations. Nakazawa developed a double-mode resonator as two acoustically coupled single resonators. And he developed 10.7MHz crystal filters using multi-energy trapping mode of thickness shear vibration. He succeeded in realizing a two-pole band pass filter response without external inductance by splitting a dot electrode to creat coupled symmetric and antisymmetric vibration modes. Accordingly, the simulation for ceramic filter were important. So that, this paper were investigated the pass frequency of filter on the electrode length and thickness of ceramic.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.899-901
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• 1993

LARGE SYNCHRONOUS GENERATORS USED IN CONNECTION WITH COMPRESSOR, TURBINE, IN MOST CASE, NEED THE HELP OF AN ELECTRICAL DRIVES FOR STARTING IN GAS TURBINES. NOWDAYS, THE STATIC FREQUENCE CONVERTER STARTING SYSTEM is EMPLOYED IN POWER PLANT. THIS PAPER DESCRIBES TORQUE CONVERTER, STATIC FREQUENCY CONVERTER AND COMPARSION OF TWO SYSTEMS.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2004.03a
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• pp.487-492
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• 2004

본 연구에서는 인공신경망 기법을 이용하여 산사태 발생원인에 대한 가중치를 구하였다. 여름철 집중호우시 산사태가 많이 발생하는 강원도 강릉시 사천면 사기막리 와 주문진읍 삼교리에 해당한다. 산사태가 발생할 수 있는 요인으로 지형도로부터 경사, 경사방향, 곡률, 수계추출을, 정밀토양도로부터 토질, 모재, 배수, 유효토심, 지형을, 임상도로부터 임상, 경급, 영급, 밀도를, 지질도로부터 암상을, Landsat TM 영상으로부터 토지이용도와 추출하여 격자화 하였으며, 아리랑1호 영상으로부터 선구조를 추출하여 l00m 간격으로 버퍼링 한 후 격자화 하였다. 이렇게 구축된 산사태 발생 위치 및 발생요인 데이터 베이스를 이용하여 인공신경망 기법을 적용하여 산사태 발생 원인에 대한 상대적인 가중치를 구하였다. 인공신경망의 역전파 알고리즘을 이용한 사기막리 지역과 삼교리 지역의 산사태 가중치를 보면 GPS를 이용한 현장조사와 위성영상을 이용한 변화탐지 기법모두의 경우모두와 훈련지역을 실제 산사태 발생 지역과 경사도가 0°인 지역, 실제 산사태 발생 지역과 Frequence ratio를 이용하여 작성한 취약성도에서 산사태 발생이 낮을 것으로 예상되는 지역, Frequence ratio를 이용한 취약성도에서 산사태 발생이 높을 것으로 예상되는 지역 과 낮을 것으로 예상되는 지역의 경우에서도 경사도는 1.5～2.5배정도 높은 상대적 가중치를 나타냈다. 이러한 가중치는 산사태 취약성도를 작성하는데 활용될 수 있다.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.2 no.2
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• pp.75-83
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• 2003

Recently, the machine tools have been needed for high speed and accuracy to increase productivity. The most Important thing to get a more stabilized machine is to know the frequency response which has an effect on manufacture a lot. This problem should be considered seriously by many researchers. There are many application programs about FEM but Just using FEM program to get information of the object is not enough to put our confidence in the stability of the machine tool design. Therefore, the purpose of this research is to make a study for proving one of the ways to design to produce stabilized a machine more efficiently by comparing FRT method and FEM. At these two tests, we can learn about the frequency response area causing resonance and we can reconfirm the result to trust.

• Korean Institute of Interior Design Journal
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• v.15 no.5 s.58
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• pp.281-288
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• 2006

Fitness center which was first introduced through hotel fitness has been disseminated into country over the years and these days it becomes a public sports facility that is available even in a small city. Fitness center usually requires a space more than 500 pyeong and even in a small fitness facility at least 200-300 pyung is in need. Also, complex structure including a space for preparing exercise and other subsidiary facility is necessary as well as various service areas to perform various exercise programs. In case of domestic fitness centers, however, proper standard and data required to compute the scale of each service area is not available due to the short of piling data. Therefore computing each space totally depends on an instinct decision of a designer or client, which may cause the fail of effective use of space. This paper aims to calculate appropriate use of space, that is, the over all space, equipment size, and movement line of each area as well as preference and frequence of use among areas is estimated in order to apply those data when computing appropriate estimation of scale.

• Journal of the Korean Society of Food Culture
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• v.7 no.2
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• pp.91-96
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• 1992

Eight hundred college students in Seoul area were surveyed for consumer behaviors and opinions about fast food restaurants at library, student center and class room from August 26 to 30, 1991. The result of this study showed that 70% of college students preferred to eat hamberger or chicken and 49% of them visited to fast food restaurants 1-3 times per month. The reasons given by students for patronizing fast food restaurants were the following, from most to least frequence: 'convenient', 'pleasant atmosphere', 'nice place to stay with friends', 'taste of food', 'speed of service', 'to be able to stay as long as I want', 'hygiene', 'variety of food price', 'nutritious food'. Majority of college students(71%) selected their food by preference, but 22% of them done by price. They were least satisfied with price and quantity of fast food. Therefore, it is important to develop domestic brand fast food restaurants to lower the price of fast food.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.1
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• pp.7-14
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• 2002

In this paper, neutral networks are used to build models of oxide film etched In CHF$_3$/CF$_4$ with a magnetically enhanced reactive ion etcher(MERIE). A statistical 2$\^$4-1/ experimental design plus one center point was used to characterize relationships between process factors and etch responses. The factors that were varied include radio frequence(rf) power, pressure, CHF$_3$ and CF$_4$ flow rates. Resultant 9 experiments were used to train neural networks and trained networks were subsequently tested on its appropriateness using additionally conducted 8 experiments. A total of 17 experiments were thus conducted for this modeling. The etch responses modeled are dc bias voltage, etch rate and etch uniformity A qualitative, good agreement was obtained between predicted and observed behaviors.

• The Journal of the Acoustical Society of Korea
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• v.9 no.3
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• pp.48-55
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• 1990

We analyze the effect of second-order sampling on estimating the mean frequency of the Doppler signal. In order to reduce the sampling frequency of analogue-to-digital converter, it is possible to obtain the Doppler signal by sampling the radio frequency echo signal with the low frequence of $4f_0$/5 or $4f_0$/9 instead of $4f_0$, where $f_0$ is the center frequency of the transmitted signal. The computer simulation and experiments show that if the narrowband signal is transmitted as is usual in the Doppler system, the error of the mean frequency estimates due to the low sampling frequency is negligible.

• Korean Journal of Clinical Pharmacy
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• v.13 no.2
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• pp.59-66
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• 2003

Filgrastim is used as an indispensable adjuvant drug to reduce the degree and duration of chemotherapy-induced neutropenia. The purpose of this research is to study the use of filgrastim by reviewing retrospective medical records of breast cancer patients who have been treated by filgtastim in the National Cancer Center. 84 patients have received 323 cycles of chemotherapy, of which 134 cycles were treated by filgrastim $(41.5\%)$. Among those 134 cycles, 34 were for prophylaxis $(21.6\%)$, and 100 for treatment of neutropenia $(74.6\%)$. The frequence of filgrastim usage was more than $50\%$ in frequency with regimens containing docetaxel. For prophylaxis, the median of filgrastim initiation was measured on the day of chemotherapy (-3rd-13th). For the treatment, on the other hand, the median appeared on the 9th day (4th-2lst) after chemotherapy, which showed very wide distribution. Time to filgrastim initiation ranged between the 7th and the 9th day after chemotherapy in docetaxel+doxorubicin combination regimen and docetaxel single regimen, whereas it showed after the 10th day in doxorubicin+cyclophosphamide combination regimens. For the treatment, 48 out of 61 patients $(73.8\%)$ in 63 cycles have experienced fever, had to visit the emergency room, required hospitalization, caused infection, transfusion, dosage reduction and schedule changes in spite of using filgrastim with chemotherapy. For prophylaxis, 11 out of 19 patients $(17.9\%)$ in 11 cycles have experienced the same results. In conclusion, the guideline of time to the initiation and the last is required for cost-effective administration of filgrastim because of the difference occurring ANC nadir, the severity and duration of neutropenia by chemotherapy regimens.

• Korean journal of applied entomology
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• v.51 no.1
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• pp.59-65
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• 2012

The black pine bast scale, $Masucoccus$ $thunbergianae$ (Hemiptera: Margarodidae), is a serious pest of the Japanese black pine, $Pinus$ $thunbergii$, in Korea. The distribution of the black pine bast scale was examined, looking overall at 686 towns (eup), townships (myeon) or neighborhoods (dong). There were Japanese black pine ($Pinus$ $thunbergii$) forests in 91 cities, counties (gun) and borough (gu), in seven provinces and three metropolitan cities during 2010. Black pine bast scale were found in 64.8% of cities or counties or borough (59) in 7 provinces and 3 metropolitan cities, and were distributed in all South Costal regions, Pohang in East Costal region and Boryeong in West Costal region. Chungcheongbukdo, Daejeon and Jeju did not have black pine bast scale. All the gu regions in Busan had black pine bast scale, of which the area with the highest prevalence was Haenam in Jeollanamdo (1.713 crawlers/0.785 $cm^2$). Songji-myeon had the highest occurrence rate (6.36 crawlers/0.785 $cm^2$) from the towns, township and dong. The density of black pine bast scale in twigs was highly correlated with percentage of the sample with scale (Correlation coefficacy=0.89).