• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.1
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• pp.168-172
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• 2012

This paper is focusing on the comparison of different kinds of BPFs(Band Pass Filters) passing signals with a particular frequency band. According to the different classifications, features and target application systems, BPF has many types. Chebyshev filter which has a steep slope and a few ripples, and Butterworth filter which has no ripple but gentle slope are the most typical BPFs. The ideal filter is flat in the passband and the slope in the transition band is perpendicular. In this paper, we suggest the cascading Chebyshev BPF with the advantages of the Chebyshev filter and the Butterworth filter simultaneously to make a closest filter to an ideal filter. The proposing BPF is the tenth Chebyshev BPF cascading the fourth and the sixth, and it is designed as the tenth cascading Chebyshev BPF. To measure the performance of the designing filter, we have compared and analyzed the tenth Chebyshev filter with the tenth Butterworth filter. As a result, the tenth cascading Chebyshev BPF has decreased the ripple more than 1/4 [dB] in the passband. Finally, the output of the simulation showed the validity of the proposing cascading Chebyshev filter.

• Journal of Chest Surgery
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• v.29 no.1
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• pp.107-111
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• 1996

Persistent bronchopleural fistula (BPF) still presents a troublesome therapeutic challenge and demands an aggressive approach when conventional measures fail. A 50-year-old man had a rigtlt pneumonectomy for far-advanced pulmonary tuberculosis with the development of postopneumonectomy empyema and BPF 1 month postoperatively in October 1 81. The condition was managed with BPF closure and the Clagett procedure, which failed with the recurrence of BPF and empyema, followed by a spontaneous open window at about 1 year port:operatively. The BPF, which had been aggravated to a large size, was managed by the closure and obliteration of the empyema cavity using a Pectoralis-skin pedicled flap 13 years postoper atively on Jul, 1994. The BPF was controlled by the procedure, and the patient, with improved respiratory symptom, was discharged 43 days postoperatively. We conclude that the use of myocutaneous flap Is an effective procedure for the closure of a large BPF. The surgical technique of the pedicled flap operation is described and the case is reported.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.4
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• pp.1-8
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• 2011

In this paper, a microstrip bandpass filter(BPF) with 3 dB bandwidth of more than 50 % at center frequency of 30 GHz was implemented. The implemented BPF is to be used as ASK(Amplitude Shift Keying) transmission and reception filters in IF band for THz transmitter and receiver capable of 10 Gb/s wireless data transmission. The microstrip BPF with ultra-wideband characteristics was implemented using a stepped-impedance lowpass filter(LPF) and a composite quarter-wave short stubs where the LPF is functioning as attenuating the upper stopband and quarter-wave short stubs is functioning as attenuating the lower stopband. The measured results are as follows; the insertion loss is 0.65 dB at 30 GHz, the stopband characteristics are -10 dB and -16 dB at 10 GHz and 50 GHz, respectively, and the passband flatness is ${\pm}0.5$ dB at 20~40 GHz.

• Journal of Navigation and Port Research
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• v.35 no.4
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• pp.299-302
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• 2011

In this letter, the effect of quality factor on center frequency deviation in miniaturized coupled line bandpass filter (BPF) with diagonally end-shorted at their opposite sides and lumped capacitors is theoretically analyzed. The miniaturized BPF of a two-stage structure with two types of quality factors in standard CMOS process was designed and manufactured at 5.5 GHz. The die area of BPF was $1.44{\times}0.41\;mm^2$. The measured center frequency of BPF with a quality factor of 4.9 was deviated from 5.5 GHz to 4.7 GHz. The one with 14.8 was shifted to 5GHz. The theoretical and measured results validate that quality factor influences the center frequency shift of BPF.

• 한국정보통신설비학회:학술대회논문집
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• 2004.08a
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• pp.3-5
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• 2004

Balanced input 단을 갖는 IC chip과의 interface를 위하여 2.4GHz 대역의 Balun BPF를 설계하였다. $2.4{\times}2.0 (mm)$ 크기의 LTCC chip 형태로 제작하기위하여 LPF-HPF 형태를 응용한 집중소자형 Balun을 설계하고 Comb-line 형태의 BPF를 접합하여 설계 및 시뮬레이션을 하였다. 시뮬레이션 결과 Balun BPF의 삽입손실은 3.03dB, 위상차는 $170^{\circ}$, Amplitude balance는 0.09dB이다.

• Tuberculosis and Respiratory Diseases
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• v.63 no.6
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• pp.507-510
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• 2007

A bronchopleural fistula (BPF) is traditionally treated by surgery, but currently various noninvasive forms of management, particularly the use of bronchoscopy, have been utilized. The substances and methods for noninvasive management of a BPF differ with individual clinicians. This case describes the use of flexible bronchoscopic treatment of a BPF complicating pneumoniausing embolization coils and intraluminally injected fibrin glue. If the BPF is small and is located on the peripheral bronchus, this minimal invasive maneuver could be recommended for the treatment of a BPF.

• Proceedings of the Korea Information Processing Society Conference
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• 2024.05a
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• pp.118-119
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• 2024

클라우드 환경에서 컨테이너 사용이 증가하면서 컨테이너 보안의 중요성이 부각되고 있다. 그리고, 이를 위해 다양한 리눅스 보안 프레임워크를 활용한 연구가 활발하게 진행되고 있으며, 특히 LSM-BPF 기술이 기존의 보안 프레임워크 한계를 극복할 수 있는 해법으로 주목받고 있다. 그러나 LSM-BPF 를 활용할 때 발생할 수 있는 시스템 성능 변화에 대한 연구는 아직 미흡한 상태이다. 따라서, 본 논문에서는 LSM-BPF 기반의 보안 솔루션을 모의 구현하고 이를 벤치마크하여 시스템 성능 변화를 측정 및 분석을 진행하였다. 컨테이너 환경에서의 실험 결과, 평균적으로 시스템 성능이 6.6% 감소하는 것을 확인하였다. 하지만, 보안 정책 개수가 증가하여도 추가적인 성능 저하는 발생하지 않음 역시 확인하였다.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.26 no.6_spc
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• pp.705-713
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• 2016

Underwater noise produced by ships has been becoming an increasing issue. A dominantly contributing noise source is a ship propeller. Therefore, it is important to predict the propeller noise at the propeller design stages. This study applied the acoustic analogy based on Ffowcs Williams equation for the prediction of the marine propeller BPF noise. A marine propeller BPF noise is investigated experimentally as well as numerically. Propeller BPF noise measurement and propeller cavitation observation tests are performed in the KRISO medium size cavitation tunnel. Numerical prediction schemes of marine propeller BPF noise are presented together with the noise measurement method. Propeller BPF noise predictions and experiments are performed under the various propeller operating conditions including non-cavitating and caveating conditions. Numerical and experimental results are compared and analyzed. It is shown that numerical prediction results are generally in good agreement with the measured data.

• Journal of the Korean Ceramic Society
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• v.40 no.10
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• pp.961-966
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• 2003

A Multi-Layer Ceramic (MLC) chip type Band-Pass Filter (BPF) using BiNb$\_$0.975/Sb$\_$0.025/ $O_4$ LTCC (Low Temperature Co-fired Ceramics) and MLC processing is presented. The MLC chip BPF has the benefits of low cost and small size. The BPF consists of coupled stripline resonators and coupling capacitors. The BPF is designed to have an attenuation pole at below the passband for a receiver band of IMT-2000 handset. The computer-aided design technology is applied for analysis of the BPF frequency characteristics. The attenuation pole depends on the coupling between resonators and the coupling capacitance. An equivalent circuit and structure of MLC chip BPF are proposed. The frequency characteristics of the manufactured BPF is well acceptable for IMT-2000 application.

• Journal of Preventive Medicine and Public Health
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• v.54 no.1
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• pp.37-45
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• 2021

Objectives: Bisphenol A (BPA) is used in the electrical, mechanical, medical, and food industries. Previous studies have suggested that BPA is an endocrine disruptor. Regulation of BPA has led to increased use of bisphenol F (BPF) and bisphenol S (BPS). However, few studies have investigated the associations of BPF and BPS with thyroid dysfunction in children. Our study investigated the associations of prenatal BPA and early childhood BPA, BPF, and BPS exposure with thyroid function in 6-year-old children. Methods: Prenatal BPA concentrations were measured during the second trimester of pregnancy in an established prospective birth cohort. We measured urinary BPA, BPF, and BPS concentrations and thyroid hormone levels (thyroid-stimulating hormone, total T3, and free T4) in 6-year-old children (n=574). We examined the associations between urinary bisphenol concentrations and percentage change of thyroid hormone concentrations using multivariate linear regression. We also compared thyroid hormone levels by dividing the cohort according to BPA, BPF, and BPS concentrations. Results: The associations between prenatal BPA and total T3 levels were statistically significant in all models, except for girls when using a crude model. The associations between urinary BPA and BPS concentrations and levels of all thyroid hormones were not statistically significant. However, we observed that lower free T4 levels (-1.94%; 95% confidence interval, -3.82 to -0.03) were associated with higher urinary BPF concentrations in girls only. Conclusions: Our findings identified significant associations between prenatal BPA exposure and total T3 levels in all children and between BPF exposure and free T4 levels in girls only.