• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2004년도 추계학술대회 논문집
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• pp.298-303
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• 2004

The active magnetic bearing system for a TMP consists of four couples of magnets, five gap sensors with its amplifiers and a digital PID controller. For stabilizing and providing damping, digital PID controller is applied for each control axes and the inter-axis cross feedback controller is also applied to suppress low frequency vibration caused by gyroscopic moment of the rotor. Therefore in this paper, a digital controller of magnetic bearing for a TMP is design and examined.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 추계학술대회 논문집
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• pp.764-765
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• 2011

In this paper, rotordynamic analyses of the Campbell diagram, critical speeds, and harmonic responses for a TMP rotor system are performed. Since the finite element model of the TMP rotor system has a very large number of degrees of freedom because of its complex geometry, and dynamic analyses for investigating the critical speeds, stability, and harmonic response are repeated for various design parameters, model order reduction (MOR) is necessary to reduce the computational cost. The Krylov-based model order reduction via moment matching significantly speeds up the rotordynamic analyses for the TMP rotor system.

• International Journal of Air-Conditioning and Refrigeration
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• 제9권2호
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• pp.8-18
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• 2001

The direct simulation Monte Carlo Method is applied to investigate the two-dimensional flow fields of a turbomolecular pump(TMP) in both molecular and transition flow regions. The pumping characteristics of the TMP are investigated for a wide range of the Knudsen number. The maximum of compression ratio and of pumping speed strongly depend on the Knudsen number in transition region, while they weakly depend on the Knudsen number in free molecular flow region. The present numerical results show good agreement with the previously known experimental data. Finally. the results of the single blade row in both molecular and transition regions are used to predict the overall performance of a TMP, which has three kinds of blade with 24-rows.

• Bulletin of the Korean Chemical Society
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• 제23권12호
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• pp.1811-1815
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• 2002

We have calculated energies and structures for the hydrogen bonded clusters between trimethyl phosphate and nitric acids. The hydrogen bond lengths between phosphoryl oxygen and the proton of nitric acid are short compared to normal hydrogen bonds, and the H-bond strengths are fairly strong. The hydrogen bond length becomes longer, and the strength becomes weaker, as more nitric acids are bound to the TMP. The average H-bond strengths for the $TMP-(HNO_3)_n$ complexes with n = 1, 2, and 3, are 9.6, 7.9 and 6.4kcal/mol at 300K respectively. Weak hydrogen bonds between nitrate oxygen and methyl proton might contribute to the stability of the clusters. Not only the BSSE but also the fragment relaxation energies should be considered to calculate hydrogen bond strengths for the complexes accurately.

• 충청수학회지
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• 제31권4호
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• pp.487-509
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• 2018

The Truncated Moment Problem (TMP) entails finding a positive Borel measure to represent all moments in a finite sequence as an integral; once the sequence admits one or more such measures, it is known that at least one of the measures must be finitely atomic with positive densities (equivalently, a linear combination of Dirac point masses with positive coefficients). On the contrary, there are more general moment problems for which we aim to find a "signed" measure to represent a sequence; that is, the measure may have some negative densities. This type of problem is referred to as the General Truncated Moment Problem (GTMP). The Jordan Decomposition Theorem states that any (signed) measure can be written as a difference of two positive measures, and hence, in the view of this theorem, we are able to apply results for TMP to study GTMP. In this note we observe differences between TMP and GTMP; for example, we cannot have an analogous to the Flat Extension Theorem for GTMP. We then present concrete solutions to lower-degree problems.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2015년도 추계학술대회
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• pp.51-53
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• 2015

In this paper, we propose an efficient sparse signal recovery algorithm referred to as the matching pursuit with a tree pruning (TMP). Two key ingredients of TMP are the pre-selection to put a restriction on columns of the sensing matrix to be investigated and the tree pruning to eliminate unpromising paths from the search tree. In our analysis, we show that the sparse signal is accurately reconstructed when the sensing matrix satisfies the restricted isometry property. In our simulations, we confirm that TMP is effective in recovering sparse signals and outperforms conventional sparse recovery algorithms.

• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2003년도 추계학술대회 발표 논문집
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• pp.50-53
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• 2003

본 연구에서는 AD 변환기, QEP(Quadrature Encoder Pulse Circuit)등 모터 제어에 필요한 주변 소자의 디지털 제어를 통해서 AC 서보 모터의 벡터 제어를[3] 구현하고 시간 지연에 의한 노이즈를 최소화하기 위해 저 전압형 DSP인 TMP320F2812를 이용하였다. TMP320F2812는 MOS 타입으로 8 depth pipeline을 가진 Harvard bus 를 채택해서 최대 150MIPS의 고속 처리 능력을 갖고 있으며 12 비트의 AD 변환기 QEP 회로와 공간 전압 벡터 PWM을 발생시킬 수 있는 기능을 가진 모터 제어용 원칩 DSP이다 모터 제어에 필요한 주변 회로들을 내장한 DSP는 하드웨어적인 구성을 간소화시키고 이로 인한 비용 절감을 얻을 수 있다. 간단한 구조로 고속 연산을 하기 위해 TMP320F2812는 고정 소수점 연산 처리 방식[6]을 사용하게 되었다. 고정 소수점 연산 처리로 인한 오차는 각 변수에 대한 스케일링을 통해 유효 자리를 확보 하는 방법을 사용하였다.

• 설비공학논문집
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• 제12권1호
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• pp.83-94
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• 2000

The performance of a turbomolecular pump(TMP) in both molecular and transition flow regions is predicted by the numerical solutions of the Boltzmann equation obtained by the direct simulation Monte Carlo method. The compression characteristics of the TMP are investigated for a wide range of the Knudsen number( Kn ). The maximum compression ratios strongly depend on Kn in transition region, while do they weakly on Kn in free molecular flow region. The present numerical results of the single blade row in both molecular and transition regions are used to predict the overall performance of a TMP, which has three kinds of blade with 24-rows.

• Bulletin of the Korean Chemical Society
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• 제13권2호
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• pp.173-176
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• 1992

The spectroscopic studies of the 5,7-dimethoxycoumarin(5,7-DMC) and 4,5',8-trimethylpsoralen(TMP) and the conformational stability of 5,7-DMC-thymidine, 4,5',8-TMP-thymine were carried out by the CNDO/S and molecular mechanics calculation. Theoretical transition energies and direction of polarizations calculated by the CNDO/S method have been used for the interpretation of the observed results. The calculated absorption spectra of 5,7-DMC are qualitatively similar to experimental ones with their characteristic visible bands. MM2 force field calculation on the possible $C_4-cyclophotoadducts$ formed between 5,7-DMC and thymidine through a cycloaddition. of $C_3$, $C_4$ bond of 5,6-DMC to $C_5$, $C_6$ bond of thymidine showed the most stable photocycloadduct to have the anti-head to tail configuration. The major photoadduct of 4,5',8-TMP-thymine has the cis-anti configuration.

• 한국응용과학기술학회지
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• 제39권6호
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• pp.924-931
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• 2022

Undenatured castor oil and trimethylolpropane (TMP) were used to obtain bio-based water-based polyurethane. Isophorone diisocyanate (IPDI) was incorporated into the formulation to obtain a transparent film, and ethylenediamine (EDA) was used for chain extension. In order to measure the change in physical properties according to the contents of castor oil and TMP, each tensile strength, elongation, and abrasion resistance test was conducted. As the contents of castor oil and TMP increased, the tensile strength increased, the elongation decreased, and the surface hardened strongly as the respective contents increased.