비선형 반향제거기의 설계

박찬호,김환용,Park, Chan-Ho,Kim, Hwan-Yong 대한전자공학회 1998 電子工學會論文誌, S Vol.s35 No.9

본 논문에서는 구현이 용이한 전이중 통신용 비선형 반향제거기의 회로구조를 제안하고자 한다. 이 회로구조는 선형 반향제거기의 FIR 구조를 사용하면서 단지 약간의 탭만 부가함으로서 선형신호 뿐만 아니라 하이브리드나 데이타 변환기 등에서 발생하는 비선형 반향신호도 제거할 수 있도록 설계되었다. 부가되는 탭의 수는 비선형 반향성분을 어느 정도까지 제거할 것인가에 의해서 좌우된다. 본 구조를 사용하여 컴퓨터 프로그램을 작성하고 시뮬레이션을 수행한 결과, 적은 탭을 추가시키는 것으로 비선형 반향신호에 대해 좋은 반향제거 효과를 나타냄을 확인하였다. This paper proposes a architecture of the nonlinear echo canceller for the full-duplex transmission, which is easy to implement. The architecture is designed to cancel the nonlinear echo signals due to the hybrid or the data converter, as well as the linear echo signals, by adding a small number of taps to the FIR structure for the linear echo cancellation. The number of tap to be add depends on how much the linear echo signals are cancelled. A computer program for this architecture was written and run. Numerical results of the computer simulations show good performances on cancellations of the nonlinear echo signals by adding a small number of taps.

다중운동 프로그램이 만성 요통 환자의 통증 강도, 몸통 근력 및 오스웨스트리 장애지수에 미치는 영향

박찬호,김재철,양영식,Park, Chan-ho,Kim, Jae-cheol,Yang, Yonng-sik 대한정형도수물리치료학회 2020 대한정형도수물리치료학회지 Vol.26 No.2

Background: The purpose of this study was to examine the effects of a multi-modal exercise program for patients with chronic low back with respect to pain intensity, trunk muscle strength and Oswestry disability index. Methods: Thirty patients with chronic low back pain were recruited and divided equally into two groups. The multi-modal training program comprised a series of exercises such as warm-up, stabilization exercises, stretching, endurance exercises, and cool down whereas the control group performed only stabilization exercises. The both group spent an equal amount of time performing 60 minutes per day, three times per week, for five weeks. Results: The experimental group demonstrated statistically significant improvements in range of motion, trunk muscle strength, the visual analogue scale, and the Oswestry Disability Index (p<.05). Intergroup comparison showed a statistically significant difference in the range of motion of the lumbar spine and the degree of disability in the experimental group. Muscle strength and pain were statistically significant in both groups. Conclusion: The multi-modal exercise program is effective for patients with chronic low back pain, as it reduces lower back pain, increases trunk muscles strength, and decrease the potential for becoming disabled.

탄소저감 도시계획 시스템의 통합화 방안 도출 연구

박찬호,김범석,Park, Chan Ho,Kim, Bum Seok 한국공간정보학회 2013 한국공간정보학회지 Vol.21 No.2

Through the rapid economic growth, modern society have achieved the industrialization but needed to respond to climate change and low-carbon green growth on a scale of urban area. Many studies about the low-carbon city and the green city are on going, but most of them are not integrated but go along in each area(construction, transportation, energy, etc) In this paper, we surveyed the current status of researches about information system to design low-carbon city or green city, and define the method to integrate the outcomes from the each area. As a result integrated model of 'Low-carbon Urban Planning integrated System' in the paper, Individual system is developed by way of C/S form because web system raised problems for data load in analysis. The integrated system was decided to develop by way of Web form, and integrated system was developed by can use the analysed DB in the individual system. We expect this study can help future researches to develop more economical and efficient integrated information system model to design the low-carbon city and the green city. 현대사회가 산업화 되고 고도성장을 이룩하며 자연환경이 훼손됨에 따라 기후변화 대응 및 저탄소 녹색성장을 위한 도시차원의 구체적인 실천대안의 필요성이 증대되고 있다. 국내에서 많은 저탄소도시 및 녹색도시 관련 연구가 진행 중에 있으나 대부분의 관련 연구들에서는 저탄소도시 혹은 녹색도시 구축을 위한 연구를 진행함에 있어 건축, 교통, 에너지 등 각 분야별로 연구를 진행하고 있기에 각 분야별 연구 결과들이 통합적으로 이용되지 않고 있다. 본 논문에서는 이러한 문제점을 해결하기 위하여 저탄소도시 혹은 녹색도시를 위한 시스템을 구축하는 관련 연구들의 현황을 조사하고, 각 분야별로 도출된 결과물을 통합적으로 이용할 수 있는 방안을 정의하고자 한다. 논문에서 정의된 '탄소저감 도시계획 통합시스템'의 통합 모델로서 각 개별 시스템을 분석 시 데이터 로드 등에 대한 문제로 인하여 C/S 시스템으로 개발하고, 통합 시스템에 분석된 DB를 조회/활용할 수 있도록 개발하며, 통합 시스템은 Web으로 개발하는 방향으로 결정하였다. 본 연구 결과를 바탕으로 차후 연구개발 사업들에서는 경제적이고 효율적인 통합 모델이 도출될 수 있을 것이며, 현장에서 실제로 각 개발 성과물들이 활용될 수 있을 것이다.

자기조직화 교사 학습에 의한 패턴인식에 관한 연구

박찬호,Park, Chan-Ho 한국정보기술전략혁신학회 2002 情報學硏究 Vol.5 No.2

On this paper, we propose SOSL(Self-Organized Supervised Learning) and it's architecture SOSL is hybrid type neural network. It consists of several CBP (Component Back Propagation) neural networks, and a modified PCA neural networks. CBP neural networks perform supervised learning procedure in parallel to clustered and complex input patterns. Modified PCA networks perform it's learning in order to transform dimensions of original input patterns to lower dimensions by clustering and local projection. Proposed SOSL can effectively apply to neural network learning with large input patterns results in huge networks size.

대전 신도시 일부 아파트지역 교통소음의 특성과 주민생활에 미치는 영향

박찬호,장성실,Park, Chan-Ho,Chang, Seong-Sil 한국환경보건학회 1999 한국환경보건학회지 Vol.25 No.3

To estimate the effects of environmental noise on inhabitants' life in an apartment area at Taejon, noise levels and traffic volume of major roads were measured. 203 housewives were surveyed by questionaires including general factors, noise related factors and three items of life effects: subjective evaluations on the general environment, annoyance, and life disturbance due to environmental noise. At the boundary adjacent to the road with more traffic volume, noise level was higher; according to the time, the amount of noise level was in the morning, in the evening, at noon, and at night in order. Most of boundary noise levels were higher than those of recommended standard environmental noise levels in a residential area. The boundary noise level showed a very significant linear relationship with traffic volume of near roads. Noise level difference in the apartments adjacent to three roads was ranged 2.4~6.7dB between in windows open and close state. The apartments adjacent to 9 lane or 6 lane-road, which were protected by noise prevention wall and 20m or more distance from the roads, showed higher noise level at middle floors and high floors than those of low floors; but the buildings adjacent to 4 lane-road, with no protection, showed higher noise level at low and middle floors than those of high floors. Among 203 housewives, 120(59.1%) participated in this study, and 86(73.2%) of them answered that the most serious environmental noise was traffic noise from near roads. Comparing traffic noise levels with those of before-migration, 67.0% participants found the environmental noise became louder. Fifty eight(49.5%) of the participants wanted noise protection wall and 15(25.9%) of them were willing to charge the fee. Less perception on the present noise comparing to those before-migration, less traffic volume, and lower noise levels in the apartments were related to higher scores of self-evaluation on the environment. Higher susceptibility on the present noise, areas with more traffic volume, higher boundary noise levels, and higher noise levels showed higher scores of annoyance on environmental noise and life disturbance. Considering above all things, it was suggested that traffic noise in this area was the major problem of environmental noise, and its' effect was so serious that inhabitants needed some preventive measures for better life quality.

Erratum: Table of contents, Vol. 37, No. 4 (December 2021)

박찬호,Park, Chan-Ho 대한턱관절교합학회 2022 구강회복응용과학지 Vol.38 No.1

대환기로 편성한 싱글 져지 대환편성물의 사행도에 관한 연구. I. 연계수와 꼬임방향을 중심으로

박찬호,심현주,김주용,Park, Chan Ho,Shim, Hyunjoo,Kim, Jooyong 한국섬유공학회 2015 한국섬유공학회지 Vol.52 No.4

Circular knitting machines are most commonly used to manufacture single jersey fabrics because of their high productivity and low costs. However, the knitted fabric exhibits skewness due to factors such as the large number of feeders, properties of twisted spun yarn, and cylinder rotating speed. The course skewness, which is especially prominent in the wale direction of plain stitch, causes fabric distortion and as a result, the distorted fabrics are unacceptable in appearance and for sewing purposes. In this work, the reasons for the skewness and their effects on the knitted fabric have been experimentally studied. The results show that course skewness is prominent and primarily caused by yarn twist. The effect of the twist direction of the knitting yarns was also studied. It was shown that the Z-twist yarns incline perpendicular to the horizontal direction of the fabric while the S-twist yarns incline in the opposite direction. This could reduce the course skewness as the feeder skewness is counterbalanced.

대환기로 편성한 싱글 져지 대환편성물의 사행도에 관한 연구. II. 사행도의 최소화 방법과 응용

박찬호,김주용,심현주,Park, Chan Ho,Kim, Jooyong,Shim, Hyunjoo 한국섬유공학회 2015 한국섬유공학회지 Vol.52 No.4

In a previous work, the causes of skewness in single jersey fabric produced on a circular knitting machine were analyzed from two aspects, namely, the machine characteristics and the yarn torsional properties. For practical reasons, the skewness caused by the machine (feeding skewness) could not be reduced, thus making it necessary to control the yarn torsion. One way of counterbalancing the yarn torsion was to alternately feed the S- and Z-twisted yarns into the knitting machine, while another method relied on using S- and Z-twisted single yarns plied together and fed through the same feeder. The results showed that a knit fabric made using plied yarn could reduce skewness. However, the hand is hard and not appropriate for this purpose. The method relying on the combined feeding of S- and Z-twisted yarn could improve the skewness while producing a pleasant touch and appearance. Nevertheless, production costs should be considered. Finally, the method relying on the alternate feeding of S- and Z-twisted yarn produced no skewness. Unfortunately, however, the fabric had a harsh appearance and was unpleasant to the touch. Taking the production costs and fabric properties into account, the use of steam set yarn is thought to offer the most practical solution.

Y 제올라이트내에서 $^{129}Xe$ 핵자기 공명의 화학적 이동을 근거로 한 알칼리 토금속 양이온의 Xe 흡착 현상 연구

박찬호,유룡,Chanho Park,Ryong Ryoo 대한화학회 1992 대한화학회지 Vol.36 No.3

알칼리 토금속 양이온을 함유하고 있는 Y 제올라이트와 Xe 간의 상호 작용을 이해하기 위하여 Xe의 흡착과 $^{129}Xe$ 핵자기 공명(NMR) 분광법을 이용하였다. 고순도의 NaY 제올라이트 시료를 합성하여 여기에 $Ca^{2+}$와 $Ba^{2+}$를 각각 이온 교환시켜서 CaY와 BaY 제올라이트 시료들을 얻었다. 부피 흡착 실험방법에 따라서 260∼320 K 사이에서 이 시료들의 Xe 흡착 등온선을 측정하였으며 296 K에서 $^{129}Xe$ NMR의 화학적 이동을 측정하였다. 이 시료들에 흡착된 Xe 기체가 제올라이트 표면과 알칼리 토금속 이온들로 구성된 흡착자리들 사이를 매우 빠르게 움직인다고 가정하였을 때 Xe의 화학적 이동을 정량적으로 설명할 수 있었다. 이 결과 알칼리 토금속 이온들이 $Na^+$ 이온이나 제올라이트 골격 표면보다도 Xe을 훨씬 더 강하게 흡착한다는 것을 의미한다. 이 연구에서는 이와 같은 흡착 세기의 차이를 이용하여 Xe 흡착 등온선을 분석하면 Y 제올라이트 수퍼케이지 속에 존재하는 알칼리 토금속 이온의 갯수를 구할 수 있다는 사실을 밝혀내었다. Interaction of xenon with alkaline-earth cations in Y zeolite supercage was studied by xenon adsorption and $^{129}Xe$ NMR experiments. The CaY and the BaY samples were prepared by exchanging $Ca^{2+}$ and $Ba^{2+}$ into a high-purity NaY zeolite. Xenon adsorption isotherms of these samples were obtained by using a conventional volummetric gas adsorption apparatus in the range of 260 to 320 K and the chemical shift in the $^{129}Xe$ NMR spectrum of the adsorbed xenon was measured at 296 K. The chemical shift against pressure was quantitatively explained assuming that the xenon gas exchanged very rapidly between various adsorption sites consisting of zeolite-framework surface and alkaline-earth ion. From this analysis, it was found that the alkaline-earth ion adsorbed xenon more strongly than $Na^+$ ion and zeolite-framework surface. Baring on the difference of the adsorption strength, the number of the alkaline-earth cations present in the zeolite supercage could be estimated by analyzing the adsorption isotherm.

UR에 대한 식량.특용작물의 문제점과 기술적대응

박찬호,Park, Chan-Ho 한국과학기술단체총연합회 1990 과학과 기술 Vol.23 No.12