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751.
Theoretical analysis and experimental investigations are presented on the resolution of a ratiometric wavelength measurement system. Theoretical modeling indicates that the resolution of a ratiometric wavelength measurement system is determined by the signal-to-noise ratio of the input signal and the noise of the photodetectors associated with optical-to-electronic conversion. For experimental verification, a ratiometric system employing a macrobending standard single-mode fiber is developed and corresponding results are in good agreement with the theoretical prediction. 相似文献
752.
Rajan Bhojwani Francesco Cellesi Assad Jalil Bruce Noble 《Contact lens & anterior eye》2011,34(6):269-273
Purpose
This study aims to address the lack of independent subjective efficacy data on artificial tear substitutes in the treatment of dry eye due to the anecdotal association of ‘thicker’ products being more effective.Methods
This is an independent study of the subjective use and efficacy of topical treatments used by members of the British Sjögren's Syndrome Association (BSSA) related to product viscosity. 2000 members of the BSSA were sent a questionnaire regarding their physical condition and the use of artificial tear substitutes. Viscosity analysis was performed on the most popular preparations. Statistical comparison is made between subjective efficacies related to substitute tear viscosity.Results
1088 patients responded giving information regarding their condition together with the subjective use and efficacy data of artificial tear substitutes. Visco-analysis was performed on the most popular preparations; these had more than 50 patients using them. In terms of subjective benefits related to viscosity for ‘frequency’ and ‘duration’ the data suggests a general trend toward viscous preparations being instilled less frequently and lasting longer; however this was not shown to be significantly correlated and some interesting comparisons are reported.Conclusions
The results confirm high levels of ocular lubricant use in the BSSA population. Our data investigates the often-anecdotal evidence that thicker preparations are more effective. However, we did not find this correlation to be statistically significant suggesting further study into factors related to subjective product efficacy. These results lay foundations for the development of future products in the treatment of severe dry eye. 相似文献753.
In this review, we provide an overview of the development of quantitative structure–property relationships incorporating the impact of data uncertainty from small, limited knowledge data sets from which we rapidly develop new and larger databases. Unlike traditional database development, this informatics based approach is concurrent with the identification and discovery of the key metrics controlling structure–property relationships; and even more importantly we are now in a position to build materials databases based on design ‘intent’ and not just design parameters. This permits for example to establish materials databases that can be used for targeted multifunctional properties and not just one characteristic at a time as is presently done. This review provides a summary of the computational logic of building such virtual databases and gives some examples in the field of complex inorganic solids for scintillator applications. 相似文献
754.
755.
Rajiv Kumar Sharma Rajan Gopal Sharma 《Quality and Reliability Engineering International》2014,30(5):745-765
Worldwide, small and medium enterprises (SMEs) have been accepted as the engine of economic growth, especially in the emerging economies, and for promoting equitable development their contribution as a component to nation's infrastructure is relatively high. Global competition forces SMEs to improve their competitiveness by enhancing their manufacturing performance. Hence, they have to pay attention to the reliability of their production processes as well as their commitment to quality management practices. In present times, because of automation and large‐scale mechanization, higher plant availability, better product quality and longer equipment life had assumed considerable significance among the SMEs. In order to meet the above challenges, adoption and practice of proactive maintenance strategies along with execution of best management practices, i.e. lean Six Sigma (LSS), has become essential for organizations to bring down maintenance and production costs. As evident from literature, both total productive maintenance (TPM) and Six Sigma are key business process strategies employed by SMEs to enhance their manufacturing performance. However, whilst there is significant research information available on implementing these systems in an independent manner, there is little information available relating to the integration of these approaches to provide a unified and highly effective implementation framework. The purpose of this paper is thus to develop an integrated model based on Six Sigma and TPM framework focusing on adding performance indicators. The goals of the study were achieved by utilizing various tools such as ‘brainstorming sessions, pareto analysis fish‐bone diagrams, histograms, FMEA, box plots, control charts and process capability plots for analysis’. While implementation of such twin framework requires greater management commitment in terms of training, resources and integration, they are also expected to provide higher levels of equipment and plant performance as evident from the results. The results show significant improvement in OEE level (Before 50, 54 and after 76, 83 for M/C –I and M/c‐II), reduction in rework (from 22% to 10%), reduction in maintenance versus operation cost (from 30% to 10%) and reduction in defect rate (from 24.82% to 5%) and average outgoing quality level (from 30% to 5%). The substantial improvement in sigma level from 2.16 and 2.64 to 4.01 and 4.12 for M/C –I and M/C‐II resulted in financial savings of approximately $2 m per annum. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
756.
757.
Arathyram Ramachandra Kurup Sasikala Afeesh Rajan Unnithan Reju George Thomas Sung Won Ko Yong Yeon Jeong Chan Hee Park Cheol Sang Kim 《Advanced functional materials》2018,28(8)
An implantable anticancer device (IAD) amenable to eradicate local regional recurrence (LRR) of breast cancer as well as to enhance the breast reconstruction during/after therapy is proposed for the first time. The IAD is fabricated by incorporating the superparamagnetic graphene oxide doxorubicin nanocomposite of size ≈200 nm in a nanofiber matrix to enable the sustained and tumor specific anticancer drug release over 60 d in vitro with a minimum initial burst release and the repeated hyperthermic capability in an alternating magnetic field to ensure the synergistic inhibition of LRR. The IAD also enriches the reconstruction of poor breast cosmesis that resulted from the surgical treatment by supporting the lipofilling of the surgical residual cavity to induce the adipogenic process. Moreover, the noninvasive monitoring capability of IAD through magnetic resonance imaging augments to the effective patient care. Thus, this work reports a new and reliable concept by introducing the multifunctional IAD possessing enhanced specificity with a real‐time monitoring capability and long‐term anticancer efficacy as a potential platform for synergistic inhibition of LRR and a great promise for the in situ breast reconstruction ability for better breast cosmesis. 相似文献
758.
The vulnerability of hearing aid devices to corrosion is critical due to their exposure to various kinds of ionic contaminants from the human body, such as sweat, sebum, and so forth, and harsh climatic conditions such as high temperature, humidity, and atmospheric pollutants. The device failure rate will vary depending upon the type of geographical location at which the device is used and root cause failure analysis is a crucial tool to understand the effect of geographical location on corrosion failures. In this study, field failed hearing aid devices from Europe, the United States, and Japan markets were investigated using a scanning electron microscope and elemental dispersive spectroscopy to locate failure mechanisms and causes. Information from the analysis was used for statistical analysis to compare the performance of the devices in the three markets based on failure percentage and failure probability for different parts and components. Solder terminals, battery contacts, light-emitting diodes, and wireless-link coil showed consistent and high failure probability across all three markets, whereas a higher failure rate for microphones was found in Europe and the United States market as compared to the Japanese market. The majority of the components corrosion failures occurred in the presence of high chloride ions from human sweat and the atmospheric conditions, whereas potassium hydroxide from the leakage of Zn–air battery was found as the additional cause for microphone failure. 相似文献
759.
Iago Hudson da Silva Souza Juliete Pedreira Nogueira Murugan Rajan Maria Terezinha Santos Leite Neta Narendra Narain 《European Journal of Lipid Science and Technology》2021,123(2):2000163
Babassu oil has high concentrations of phenolic compounds. When seeds are preheated, these compounds tend to migrate to the oil depending on the degree of roasting applied. This study aims to optimize the roasting conditions of babassu seeds using response surface methodology (RSM) and the desirability functions. A central composite rotational design (CCRD) is employed to investigate the effects of two independent variables, temperature (X1) and roasting time (X2) which significantly affected response variables, namely yield (%), total phenolics content (TPC), number of phenolic compounds, oxygen radical absorbance capacity, acid value and peroxide value. The quadratic model is adjusted for most responses. The roasting temperature of 222 °C and the roasting time of 43 min are standardized as ideal conditions. Thus, the oil produced at the optimized conditions shows a yield of 54.47% and TPC of 91.53 mg GAE/100 g. In the control oil sample, the presence of phenolic compounds analyzed by HPLC-DAD is not observed while under optimized conditions, seven phenolic compounds are observed. The model of optimized conditions shows a good correlation between the predicted and experimental values. In general, these results demonstrate the effectiveness of optimum roasting conditions in improving the quality of bioactive compounds in babassu oil. Practical Applications : This work aims to optimize the babassu seeds roasting process to obtain oil with a greater number of phenolic compounds and better antioxidant capacity. As the first study on babassu seeds roasting, it contributes to the generation of important data in relation to the identification and quantification of phenolic compounds in the oil. Finally, the optimum roasting conditions established in this work can be explored commercially in babassu oil extraction. 相似文献
760.
S. Pandia Rajan S. Senthil Kumaran L. A. Kumaraswamidhas S. Muthukumaran 《Journal of Mechanical Science and Technology》2016,30(1):337-344
Friction welding of tube to tube plate using an external tool (FWTPET) is a relatively newer solid state welding process used for joining tube to tube plate of either similar or dissimilar materials with enhanced mechanical and metallurgical properties. In the present study, FWTPET has been used to weld SA 213 (Grade T12) tube with SA 387 (Grade 22) tube plate. The welded samples are found to have satisfactory joint strength and the Energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD) study showed that inter metallic compound is absent in the weld zone. The different weld joints have been identified and the phase composition is found using EDX and XRD. Microstructures have been analyzed using optical and Scanning electron microscopy (SEM). The mechanical properties such as hardness, compressive shear strength and peel test for different weld conditions are studied and the hardness survey revealed that there is increase in hardness at the weld interface due to grain refinement. The corrosion behavior for different weld conditions have been analyzed and the weld zone is found to have better corrosion resistance due to the influence of the grain refinement after FWTPET welding process. Hence, the present investigation is carried out to study the behavior of friction welded dissimilar joints of SA 213 tube and SA 387 tube plate joints and the results are presented. The present study confirms that a high quality tube to tube plate joint can be achieved using FWTPET process at 1120 rpm. 相似文献