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231.
BV Howard EJ Mayer-Davis D Goff DJ Zaccaro A Laws DC Robbins MF Saad J Selby RF Hamman RM Krauss SM Haffner 《Canadian Metallurgical Quarterly》1998,47(10):1174-1179
The study purpose was to explore the association between dyslipidemia and insulin resistance in three ethnic groups. The Insulin Resistance Atherosclerosis Study (IRAS) is a multicenter epidemiologic study conducted at four clinical centers in California, Texas, and Colorado. The study population for this analysis consisted of 931 non-Hispanic white, African American, and Hispanic men and women (aged 45 to 64 years) without diabetes. The IRAS clinical examinations included lipoprotein measures, a 75-g glucose tolerance test, and the frequently sampled intravenous glucose tolerance (FSIGT) test. The results show a consistent relationship between insulin-mediated glucose disposal and dyslipidemia in African American, Hispanic, and non-Hispanic white men and women. Further, LDL size was inversely associated with insulin resistance in all three ethnic groups. These findings indicate that dyslipidemia is a fundamental part of the insulin resistance syndrome in all of the ethnic groups studied. 相似文献
232.
In this work, the natural radionuclide concentrations of the 226Ra, 228Ra, 232Th and 40K were estimated from samples of cattle and poultry fodder, South Valley University farms and Qena Governorate farm, Qena, Upper Egypt. The radionuclide concentrations and annual consumption rate of twenty-nine animal fodders were analyzed using low-level γ-spectrometer, including a mixture fodder, silage, hay, rice straw, and poultry fodder. The irradiation risk of human health was assessed due to indirect ingestion of the beef, milk, poultry and egg, the annual effective dose of the radionuclides for the local consumer was 2.7, 14, 0.1, and 0.14 μSv·y–1, respectively. 相似文献
233.
Gul Beenish Khan Imran Ali Mustafa Saad Khalid Osman Khan Atta ur Rehman 《The Journal of supercomputing》2019,75(11):7606-7624
The Journal of Supercomputing - Cloud computing provides online services and solutions for dynamic and on-demand resource provisioning. These resources consume high energy leading to higher... 相似文献
234.
Roadworks (work zones) are a common feature of our urban environment. They have a considerable impact on reducing roadway capacity, causing interruptions and imposing substantial delays to road users, which in turn adds to the cost to society and adverse impact on road safety. Shuttle-lane (alternate one-way working) is one of the most commonly used traffic management arrangements at urban roadworks as most of the urban road network is built up from single carriageway. 相似文献
235.
This paper is considered as an application of a centralized control non orthogonal multiple access (NOMA) based cognitive radio network. Here, a base station (BS) sends simultaneously two information signals by employing the superposition coding scheme to two different types of users, i.e., group of near users and one far user. The near users, namely, the secondary users, exchange cooperatively their own received information among themselves ensuring the realization of maximal diversity gain. Besides, they are responsible for relaying information to the far user, namely, the primary user. One potential secondary user is selected to decode and forward the BS information signal to the primary user and the rest of the secondary users to reinforce the reliability, as well as, mitigate the non-decodable messages. Two equivalent cases of a relay (secondary user) selection scheme are proposed. In the first case, the selection aims at maximizing the minimum of the joint secondary to secondary (S to S) and secondary to primary (S to P) channels’ coefficients under a certain limit of interference condition. In the second case, the selection aims at maximizing the minimum of the BS to S and S to S paths while a certain quality of service of the primary user is strictly guaranteed. Assuming Rayleigh fading channels, new closed form expressions are derived for the achievable capacity associated with the two information signals. Simulation results reveal the advantage of our proposed schemes over the conventional orthogonal max–min approach and confirm the validity of our analysis. 相似文献
236.
Structural Health Monitoring (SHM) is about the mechanical strength and stability of a structure. The methods used to reveal and quantify the structure quality could be different in nature. Strain change is, however, the common structural parameter indicating structure condition in time. Strains can give rise to cracks in civil structures that will grow exponentially in time. The most common way of measuring strain in structures is by using the Metal Foil Strain Gauge (FSG). This paper proposes the use of Thick Film Ceramic Strain Gauge Sensors (TFCSs) as an alternative to measure strain on beams. A 4-point bending test (4PBT) was conducted to show the difference in response of the mentioned two kinds of strain gauges; TFCS and FSG, and then thick film ceramic sensor was applied to observe the stability of sample brick column. 相似文献
237.
This article presents combinations of the generic phase-shifted pulse-width modulation method with conventional discontinuous pulse-width modulation methods operated in the over-modulation range. The treated discontinuous methods are the third harmonic injection, Depenbrock's DPWM1, and Ogasawara's DPWM2. The significant advantage of the present approach over the conventional phase disposition pulse-width modulation method is the equal power flow between the H-bridges and the improved distribution of the switching operations number between them. Furthermore, they provide improved linearity in the over-modulation range. The proposed pulse-width modulation methods are analyzed by extensive simulation results. Several aspects, such as the total harmonic distortion factor of the inverter output currents and voltages, harmonic content, frequency spectrum distribution, and switchings number, are studied. 相似文献
238.
This article presents a comparative analysis of 12-, 18-, 24-, and 36-pulse rectifier topologies supplying 3-phase three-level H-bridge inverters as active loads. The analysis comprises the total harmonic distortion data of the inverter and grid currents and voltages, including inter-modulation harmonics. This article shows that the rectifier-inverter connection produces inter-modulation harmonics between the grid and inverter frequencies. As a result, inter-modulation and sub-harmonics are present in the grid currents. This article presents an analysis and comparison of these inter-modulation effects for the mentioned topologies. Moreover, it is shown that the inter-modulation effects can be reduced by increasing the capacitance of DC-link capacitors, increasing grid series inductance, and using rectifiers with high number of pulses. The analysis is validated by extensive simulation results. 相似文献
239.
A high gain like observer with updated gain is proposed for a class of cascade nonlinear and non triangular systems that are observable for any input. The objective of the gain adaptation is to perform an admissible tradeoff between state reconstruction dynamics on the one hand versus noise amplification on the other hand. To this end, the gain of the proposed observer is tuned through a single scalar time-varying parameter governed by an adequate differential Riccati equation. The involved adaptation process is mainly driven by the power of the output observation error norm computed on a moving horizon window. Simulation results are given to show the effectiveness of the proposed observer, namely its exponential convergence and its insensitivity with respect to noise measurements. 相似文献
240.
A method is presented which suggests the sharing out of total cell short circuit current among the constituent parallel branches of the equivalent circuit, allowing for the identification of their contributions to the total current–voltage (I–V) characteristics under illumination in solar cells described through two parallel diodes. The method is based on the fact that all parallel branches are always under the same voltage; in particular, the open circuit voltage is the same for the cell as a whole as well as for each of the two diodes. With the help of the parameters of each diode and its share in the cell short circuit current, its light I–V characteristic can be drawn, and its individual fill factor calculated. Furthermore, the method suggests a way to estimate the cell fill factor with the help of the individual fill factors. The application of the method is carried out on experimental data of a ZnO/CdS/CuGaSe2 single crystal solar cell. 相似文献