Wyniki wyszukiwania - Biblioteka Nauki

1

Dual manipulator system calibration based on virtual constraints

100%

Zhu Q. , Xie X. , Li C.

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tom Vol. 67, nr 6

1149--1159

EN

Calibration is necessary for dual manipulator to complete operational tasks. This paper proposes an effective robot-robot and hand-eye calibration method based on virtual constraints. Firstly, a rotational error model and a translational error model are established based on the relationships between the transformation matrices of the dual manipulator calibration system. Then a poses-alignment method is designed to make the poses of the two robots satisfy the constructed virtual constraints. At the aligned positions, the joint angles of the two robots are saved and used to calculate the values of the variables in the error models. Finally, the robot-robot and hand-eye rotational errors are estimated by an iterative algorithm. These errors are then used to calculate translational errors based on the SVD (singular value decomposition) method. To show the feasibility and effectiveness of the proposed method, experiments of robot-robot and hand-eye calibration for dual manipulators are performed. The experiment results demonstrate that the accuracy of the dual manipulator system is improved greatly.

2

Dual manipulator system calibration based on virtual constraints

100%

Zhu Q. , Xie X. , Li C.

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nr 6

3

A Type Design Method of Large Hydraulic Turbine Based on The Gaussian Mixture Model

100%

Lin L. , Zhong S. , Xie X.

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tom R. 88, nr 9b

153-156

EN

Because of the complex fluid motion in hydraulic turbine and the imperfect design theory, the selection design of Large-scale hydraulic turbine is achieved based on the calculation and analysis on the synthetic characteristic curves, which is subjectivity and low efficiency. To solve this problem, the Gaussian mixture model is used to extract the geometric features from the synthetic characteristic curves so that the retrieval process of the model wheel can be achieved by these geometric features. The search model of the running area from the synthetic characteristic curves is build based on the contour curve similarity transformation method. In the paper, the Monte Carlo method is adopted to obtain the mean values of the synthetic characteristics in the running area so that the evaluation targets can be established by combining the mean values with the hydraulic turbine design experiences. Finally the validity of running area can be evaluated by the evaluation targets. The test results show that the accuracy and efficiency of the selection design of Large-scale hydraulic turbine can be improved by the proposed method.

PL

W artykule przedstawiono problemy projektowania dużych turbin hydraulicznych. Zaproponowano model matematyczny bazujący na mieszanym modelu Gaussa w celu wydobycia parametrów geometrycznych. Zaadaptowano metodę Monte Carlo do określania średnich wartości syntetycznych charakterystyk w obszarze pracy.

4

In-vitro monitoring and chemiluminescence detection of sub-nanogram amount of vitamin C in human urine

88%

Song Z. , Yue Q. , Xie X. , Bian L. , Lei G.

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tom Vol. 51, No. 4

499-508

EN

A sensitive, simple, and rapid chemiluminescence method has been employed for monitoring of sub-nanogram level of vitamin C in human urine. The procedure was based on strong decrease of chemiluminescence by vitamin C in reaction with luminol and periodate. It has been found that quenching of chemiluminescence was linearly proportional to the logarithm of vitamin C concentration in the range of 0.1-100 ng mL-1. The analytical procedure, including sampling and washing, was completed within 0.5 min, giving an analytical throughput of 120 samples per hour. The limit of detection was 0.03 ng mL-1(3σ) and relative standard deviation was lower than 2.5%. The proposed method was successfully applied to the monitoring of excretion of vitamin C with human urine during 24 h after oral administration of tablets of vitamin C. Possible mechanism of chemiluminescence changes has been also discussed.

PL

Opracowano czułą, prostą i szybką metodę monitorowania witaminy C w ludzkim moczu na poziomie ułamków nanogramów. Opracowana procedura jest oparta na silnym obniżeniu chemiluminescencji w układzie luminol/jodan(VII) przez witaminę C. Stwierdzono, że spadek intensywności chemiluminescencji jest wprost proporcjonalny do logarytmu ze stężenia witaminy C w zakresie 0,1-100 ng mL-1. Procedura analityczna , włączając próbkowanie i mycie, może być przeprowadzona w ciągu 0,5 min, co daje wydajność 120 analiz na godzinę. Granicę wykrywalności określono na 0,03 ng mL-1 (3σ), a względne odchylenie standardowe było niższe od 2,5 %. Opracowana metoda została z sukcesem zastosowana do monitorowania wydzielania witaminy C z moczem w czasie 24 godz. po połknięciu tabletek.Możliwy mechanizm zmian chemiluminescencji był również dyskutowany.

5

Lithium Manganate Grown from Water-Solubility Explosive with EPS

75%

Xie X. , Wu H. , Wang W. , Wang M. , Huang W. , Li X.

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tom Vol. 3, nr 3

15-25

EN

Nanostructured spherical spinel lithium manganate with about 30 nm in diameter was synthesized for the first time by explosive method. The water-solubility explosive was prepared using a simple facility at room temperature. The growth of lithium manganate via detonation reaction was investigated with respect to the presence of an energetic precursor, such as the metallic nitrate and the degree of confinement of the explosive charge. The detonation products were characterized by scanning electron microscopy. Powder X-ray diffraction and transmission electron microscopy were used to characterize the products. Lithium manganate with spherical morphology and more uniform secondary particles, with smaller primary particles of diameters from 10 to 50 nm and a variety of morphologies were found. Lithium manganate with a fine spherical morphology different from that of the normal spinel is formed after detonation wave treatment due to the very high quenching rate. It might also provide a cheap large-scale synthesis method. Explosive detonation is strongly nonequilibrium processes, generating a short duration of high pressure and high temperature. Free metal atoms are first released with the decomposition of explosives, and then theses metal and oxygen atoms are rearranged, coagulated and finally crystallized into lithium manganate during the expansion of detonation process.

6

An HPLC method for the determination of the anticancer complex 3-hydroxycarboplatin

75%

Yang S. , Chen X. , Zhen P. , Ye Q. , Xie X. , Liu W.

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tom Vol. 23, no. 4

539--550

EN

A simple and rapid HPLC method using a photodiode array (PDA) detector for the analysis of 3-hydroxycarboplatin and its related complex has been established for the first time. Separation of 3-hydroxycarboplatin and 3-hydroxy-1,1-cyclobutanedicarboxylic acid (3-HO-cbdca) was carried out on a Phenomenex ODS3 column using an aqueous solution containing 50 mM ammonium acetate and 5 mM sodium 1-octanesulfonate as the mobile phase. The flow rate was 0.8 mL min-1, the column temperature was 40°C, and the detection wavelength was 230 nm for 3-hydroxycarboplatin and 220 nm for 3-HO-cbdca. Different analytical performance parameters such as precision, accuracy, linearity, stability of the solution, specificity, limit of detection (LOD), limit of quantification (LOQ), and system suitability were determined using the Empower 2 software. The calibration curve of standard 3-hydroxycarboplatin showed good linearity (r = 0.9995) within the range 0.5–1.4 mg mL-1. The method was accurate and precise, with an average accuracy of 100.4% (RSD = 1.53%, n = 9), and the results of the system suitability test showed symmetrical peaks, good resolution (Rs), and repeatability. It can be applied to the quality control of 3-hydroxycarboplatin.