• Applied Chemistry for Engineering
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• v.9 no.6
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• pp.852-856
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• 1998

Effects of packing materials on the pressure fluctuations in a fluidized bed have been analysed using statistical method to interpret fluidized bed behavior. The experiments were carried out in a fluidized bed of 6.7cm - ID, and the experimental variables were particle size and its distributions, fluidizing velocity, aspect ratio, and packing materials, etc. Screen packings are used as packing material, the properties of the pressure fluctuations in the fluidized bed were measured by a differential pressure transducer. The measured properties for the pressure fluctuations were the mean, the standard deviation, and the major frequency of the power spectral density functions, etc. The standard deviations of the pressure fluctuations have been slightly affected in the radial directions of fluidized bed, and almost constant in axial directions the height above 4.5cm of the distributor of fuidized bed without packing materials. The major frequency decreased with increaing packing size, whereas it showed maximum at 10% of packing materials. It has been found that the standard deviation of the pressure fluctuations can effectively explain the fluidized phenomena, and the packing materials severely affected the properties of the pressure fluctuations.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.159-162
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• 1997

This paper describes robust stabilization of nonlinear single-input uncertain systems without matching conditions. We consider nonlinear systems with a vector of unknown constant parameters perturbed about a known value. The approach utilizes the generalized controller canonical form to lump the unmatched uncertainties recursively into the matched ones. This can be achieved via nonlinear coordinate transformations which depend not only on the states of the nonlinear system but also on the control input. Then the dynamic robust control law is derived and the stability result is also presented.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.453-456
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• 1996

In this paper, the direct adaptive control using neural networks is presented for the control of chaotic nonlinear systems. The direct adaptive control method has an advantage that the additional system identification procedure is not necessary. In order to evaluate the performance of our controller design method, two direct adaptive control methods are applied to a Duffing's equation and a Lorenz equation which are continuous-time chaotic systems. Our simulation results show the effectiveness of the controllers.

• Proceedings of the Optical Society of Korea Conference
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• 2000.02a
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• pp.38-39
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• 2000

마치 살아있는 것처럼 움직이는 영상을 보고자 하는 인류의 욕구가 19세기에 다양한 광학 기구들을 낳게 했는데, 이 중의 하나가 영화이다. 이러한 필름을 기초로 한 투사기술은 그러한 인간의 욕구를 작게나마 해소시켰지만, 수평선 저 너머에서 일어나는 일을 동시에 눈으로 보고 싶어하는 꿈을 실현시켜 주진 못했다. 하지만 이러한 생방송을 할 수 없는 필름기술의 한계는 CRT라고 하는 전자 투사 디스플레이(electronic projection display)의 도움으로 극복되었다. (중략)

• LP가스
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• s.85
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• pp.22-33
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• 2003

백승홍의원이 발의해 주진되던 LPG법개정안이 협회의 반대로 국회통과가 무산됐다. 협회는 백승홍의원의 LPG법개정안은 유통단계를 고착화시켜 판매사업자의 가격회포에 따른 소비자피해가 우려되며, 정부의 규제완화와 경쟁촉진에도 맞지 않으며, 사업자간 담합 우려, 소비자의 선택권 제한, 기존 판매사업자에 대한 특혜시비 등 여러가지 문제점이 있음을 지적하고 백의원측과 산업자원부에 제출한 바 있다. 협회는 또한 국회 산업자원위원들에게도 동 내용을 전달했으며 충전사업자의 서명을 반대하는 등 꾸준히 반대의견을 개진했었다.

• 건강소식
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• v.14 no.12 s.145
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• pp.2-5
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• 1990

지금 이 순간에도 어느 병원 분만실에서는 탄생의 기쁨을 알리는 아이의 울음소리가 우렁차게 울려나고 있다. 그러나 그중에는 결코 기쁨만으로 느껴지지 않는 울음소리가 있다. 선천성 대사이상으로 인한 정신박약아의 출생. 우리나라에서만 1년에 300명 정도라고 한다. 그러나 더더욱 안타까운 것은 신생아기에 발견만 되었으면 정신박약아로의 성장이 아닌 정상인으로의 성장이 가능함에도 이들이 방치되고 있다는 사실이다. 이미 모든 신생아에게 선천성 대사이상 검사가 실시되고 있는 선진각국의 추세를 감안, 몇 년 전부터 국내에서도 제기되고 실시되기 시작한 이 검사가 현재 어느 정도까지 주진되었는지를 이번호에서 알아보기로 한다.

• Proceedings of the KIEE Conference
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• 1995.07b
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• pp.658-660
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• 1995

This paper presents a performance analysis of the multiple sliding mode control for SISO system. The multiple sliding mode control technique uses sliding surfaces for each state. The performance analysis is done by comparison between the multiple sliding mode control and the sliding mode control. Overall performance of the multiple sliding mode control is improved over that of the sliding mode control. Results of numerical simulations are presented.

• Quality Improvement in Health Care
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• v.5 no.2
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• pp.216-223
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• 1998

We surveyed the discordance rate of principal diagnosis made at emergency room(ER) & made at ward on discharge of the patients. Subjects were four hundred eighty cases who came to the ER of one third-line hospital from January 1, 1998 to January 31, 1998. The discordance rate was higher in patients admitted to medical department(8.2%) than surgical department(1.5%). If the patients were transferred to other department during hospital stay, discordance rate increased from 3.3% to 6.3%. In conclusion, discordance rate of principal diagnosis made at ER and made at ward was higher in patients with complicated problems. Medical record department should keep these findings in mind if it has a plan to support the management of ER record.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.25 no.1
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• pp.24-28
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• 1989

This paper describes a fundamental method to suppress vibration of a structure under excitation by attaching a impact absorber. The influence of the shape of impact absorber, such as weight of add mass, impact clearance, contacting area and the exciting frequency on suppressing vibrations of the structure is investigated. The effectiveness of the proposed vibration absorber is demonstrated experimentally.

• Journal of the Daesoon Academy of Sciences
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• v.38
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• pp.183-208
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• 2021

In order to examine the origin of Image-Number Theory in Cho Hoik (曺好益)'s Yixiangshuo (易象說), it is necessary to review Hu Yigui (胡一桂)'s Zhouyi Benyi Fulu Zuanzhu (周易本義附録纂注). Hu Yigui based his work on Zhu Xi's Zhouyi Benyi, he took related contents such as the Zhu Xi's writings and phrases and organized them into a fulu (附録), and he collected commentaries that matched the meaning of Zhouyi Benyi among the theories of many Confucian scholars and produced a zuanzhu (纂注). In addition to these, there are 'Yuwei (愚謂)' and 'Yuan (愚案)' which allowed him to add his own opinion. The system of Hu Yigui's Zhouyi Benyi Fulu Zuanzhu almost coincides with Cho Hoik's Yi-ological writing system. In other words, Cho Hoik appears to have written Yizhuan Bianjie (易傳辨解) and Zhouyi Shijie (周易釋解) as a fulu and zuanzhu of Zhouyi Benyi Fulu Zuanzhu. And there is Yixiangshuo which corresponds to 'Yuwei' and 'Yuan' of Zhouyi Benyi Fulu Zuanzhu. Yixiangshuo was not originally an independent Yi-ological book, but was compiled by later generations from what was recorded in the form of the head notes of Zhouyi (周易). Thus, Yixiangshuo takes almost the same form as the 'Yuwei' and 'Yuan' of Zhouyi Benyi Fulu Zuanzhu. In addition, Cho Hoik's Yixiangshuo cites many contents from 'Yuwei' and 'Yuan' of Zhouyi Benyi Fulu Zuanzhu. On the other hand, in order to examine the origin of Image-Number Theory in Cho Hoik's Yixiangshuo, the Yi-ology of Zhu Zhen (朱震) cannot be overlooked. This is true not only due to the fact that Yixiangshuo is quoting Zhu Zhen. The more significant reason is Yixiangshuo is a fundamental aspect of Zhu Zhen's Yi-ology. As demonstrated in the main body of this article, the methodology of Image-Number Theory in Yixiangshuo and its counterpart in Hanshang Yizhuan (漢上易傳) are almost identical. In conclusion, the origin of Image-Number Theory in Cho Hoik's Yixiangshuo can be found in both the Hu Yigui's Zhouyi Benyi Fulu Zuanzhu and Zhu Zhen's Hanshang Yizhuan. In particular, it can be said that its origin can be found in both the 'Yuwei' and 'Yuan' of Zhouyi Benyi Fulu Zuanzhu and the methodlogy of Image-Number Theory in Hanshang Yizhuan.