A Generalized Method of Decreasing Data Redundancy

Bayesian estimation of abundance based on removal sampling under weak assumption of closed population with catchability depending on environmental conditions. Application to tick abundance

The measurement of total volatile organic compound (TVOC) is effective for evaluating indoor air quality. This study aimed to develop a procedure for TVOC measurement using a passive solvent extraction method (SD_passive). The quantitative and qualitative performances of SD_passive for TVOC measurement were compared to those of the active thermal desorption method (TD_active). TVOC concentrations of the SD_passive method were highly correlated with those of the TD_active method. However, below 600 μg/m3, they were slightly underestimated compared to those of the TD_active method. This was because the sampling rates (SRs) of specific volatile organic compounds (VOCs), such as cyclic siloxane and nonanal, which are often detected in indoor air, were lower than those of toluene used for calculating TVOC concentration in the SD_passive method. Therefore, several correction methods using the appropriate SR were explored to obtain TVOC concentrations equivalent to those obtained using the TD_active method. In the proposed method, individual SRs were used for specific VOCs and estimated SRs were used for other VOCs as a function of the total ion chromatogram retention time (Rt) (SR = 96, Rt < 25; SR = − 3.2, Rt + 150, Rt ≧ 25). Consequently, below 600 μg/m3, the SD_passive method could achieve a qualitative performance equivalent to that of the TD_active method. The ten major compounds of TVOC identified using the SD_passive method agreed with those using the TD_active method. Overall, the proposed method is easy to implement, inexpensive, and suitable for rapid evaluation of indoor air quality.

Sequential equivalent time sampling (ETS) has been extensively used in data acquisition instruments (e.g., sampling oscilloscopes and time domain reflectometers). A novel step delay method is proposed based on the frequency difference to obtain a higher sampling rate in sequential ETS. It is different from the classic step delay methods and is capable of increasing the sampling rate. The sampling clock and the repetitive signal are taken as examples in this study. The time-frequency conversion relationship indicates that a fine step delay will be generated in the time domain if there is a frequency difference between the two in the frequency domain. The core of the proposed method is the selection of the appropriate frequency difference (step delay) according to the desired equivalent sampling rate. Two experiments were performed to verify the proposed method. The feasibility of the proposed method is verified using a digital storage oscilloscope. Four cases are examined in the experiment, and the final equivalent sampling rate is obtained as 5 PS/s for the equivalent sampling of a 4.999 995GHz (or higher) signal. A data acquisition system with a 10 MS/s real-time sampling rate is designed to verify the feasibility of the proposed method, obtaining a theoretical equivalent sampling rate of 585 GS/s. The theoretical equivalent sampling rate and the examined equivalent sampling rate are consistent. The equivalent sampling waveform and real-time sampling waveform of a 1GHz signal are compared, and the comparison result suggests that the proposed method can acquire more waveform information. The proposed method obtains a high equivalent sampling rate for repetitive signals, and techniques (e.g., oversampling) are given to obtain higher vertical resolution. The proposed method, combined with a sample-and-hold amplifier, can also achieve a higher analog bandwidth.

Currently, the use of speech recognition is increaseingly in many applications such as mobile device interaction, interactive voice response system, voice search, voice dictation and voice identification. The heart of such applications is speech features needed to represent input signals. However, in real applications, speech signals are sampled with various sampling rates. The different sampling rates of input speech lead to the different features. This makes the speech recognition rate dropping. Therefore, this paper proposes an independent resolution descriptor based on fractal codes obtained by fractal encoding and decoding processes. The encoding process extracts fractal codes from partitioned speech signals, whereas the decoding process reconstructs independent resolution speech signals from the fractal codes. This method can effectively reconstruct speech signals at any sampling rates, especially at a higher sampling rate, which is a grand challenge. The proposed method is evaluated the performance by testing with AN4 corpus of CMU Sphinx speech recognition engine. The experimental results show that the proposed method can improve the accuracy of speech recognition, even if the sampling rate of testing speeches differs from that of training speeches.

Predicting quality of services (QoS) is an important need when ranking cloud services for selection. QoS values of cloud services usually depend heavily on the user’s and service’s environments. Therefore, personalized QoS value prediction for cloud services is more desirable to users. Collaborative Filtering (CF) has recently been applied to personalized QoS prediction for services on the Web. However, seldom did they take the context information of service users and services into consideration. The following paper presents a CF-based method for predicting QoS values of cloud services. The method exploits not only the QoS information of users and services, but also one type of the most important context information of users and services, i.e., their geographic locations. Experiments conducted on a real dataset show that geographic location information is indeed helpful for improving the QoS prediction performance. The experimental results also demonstrate that the proposed method is significantly better than previous methods in prediction accuracy.

Determination of vitamin D3 in pharmaceutical products using salting-out assisted liquid–liquid extraction coupled with reversed phase liquid chromatography

PurposeThis paper aims to present an integrated method for optimized project duration and costs, considering the size and cost of crews assigned to project activities' execution modes.Design/methodology/approachThe proposed method utilizes fuzzy set theory (FSs) for modeling uncertainties associated with activities' duration and cost and genetic algorithm (GA) for optimizing project schedule. The method has four main modules that support two optimization methods: modeling uncertainty and defuzzification module; scheduling module; cost calculations module; and decision-support module. The first optimization method uses the elitist non-dominated sorting genetic algorithm (NSGA-II), while the second uses a dynamic weighted optimization genetic algorithm. The developed scheduling and optimization methods are coded in python as a stand-alone automated computerized tool to facilitate the developed method's application.FindingsThe developed method is applied to a numerical example to demonstrate its use and illustrate its capabilities. The method was validated using a multi-layered comparative analysis that involves performance evaluation, statistical comparisons and stability evaluation. Results indicated that NSGA-II outperformed the weighted optimization method, resulting in a better global optimum solution, which avoided local minima entrapment. Moreover, the developed method was constructed under a deterministic scenario to evaluate its performance in finding optimal solutions against the previously developed literature methods. Results showed the developed method's superiority in finding a better optimal set of solutions in a reasonable processing time.Originality/valueThe novelty of the proposed method lies in its capacity to consider resource planning and project scheduling under uncertainty simultaneously while accounting for activity splitting.

In the manual impact excitation technique, which is usually used for the measurement of structural dynamic stiffness of machine tools and other machineries, it is necessary to repeat impact excitations and average the measured data to remove the effect of disturbances. However, it is difficult to repeat the same excitations exactly because of the manual operation. Consequently, too weak impacts or multiple impacts, which result in poor signal-to-noise ratio, often occur. The present paper describes a practical measuring method in which a reference exciting force and certain permissible deviations are determined in advance and only the excitations within the permissible range are accepted. Experimental results show that the proposed method is not only useful to the improvement of measuring accuracies but also helpful to the investigation of nonlinear characteristics of the structures.

This paper proposes a highly efficient single-phase three-level neutral point clamped (NPC) converter operated by a model predictive control (MPC) method with reduced commutations of switches. The proposed method only allows switching states with none or a single commutation at the next step as candidates for future switching states for the MPC method. Because the proposed method preselects switching states with reduced commutations when selecting an optimal state at a future step, the proposed method can reduce the number of switchings and the corresponding switching losses. Although the proposed method slightly increases the peak-to-peak variations of the two dc capacitor voltages, the developed method does not deteriorate the input current quality and input power factor despite the reduced number of switching numbers and losses. Thus, the proposed method can reduce the number of switching losses and lead to high efficiency, in comparison with the conventional MPC method.

This work presents a sensitive, accurate and selective RP-HPLC method for simultaneous determination of cyproheptadine HCl (CPH), its impurity B (dibenzosuberone) and CPH oxidative degradation product (10,11-dihydroxy-dibenzosuberone) in bulk powder and in pharmaceutical formulation. The RP-HPLC method depends on isocratic elution using C8 column and mobile phase consisting of 0.05M KH2PO4 buffer:methanol (35:65, v/v, pH=4.5) at a flow rate of 2mL/min, and the eluant was monitored at 245nm. Good resolution was obtained with tR values of 3.05, 7.54 and 6.17min for CPH, impurity and oxidative degradate, respectively. The proposed method has been validated as per ICH guidelines using pure forms of CPH, its impurity and degradation product in pharmaceutical formulation with an accuracy of 100.48, 100.16 and 100.11, respectively. Additional spiking experiments yielded an accuracy of 100±1.6%. Repeatability and intermediate precision results indicated acceptable low <2% RSD values. Moreover, the developed method's statistical results were favorably compared to the previously reported method results regarding both accuracy and precision. The developed method can be applied for analysis of the three components in quality control laboratories.

Objective: To develop and validate new, simple and rapid analytical method for determination of related impurities in isosulfan blue drug substances by the liquid chromatographic method as per ICH guidelines.Methods: The chromatographic separation obtained between drug substance i.e. isosulfan blue and its related impurities (Impurity-A, Impurity-B and Impurity-C) on C18 (100 x 2.00 mm) 1.9µ UPLC column using a mobile phase system containing 0.1 % perchloric acid in water (Mobile phase A) and 0.1 % perchloric acid in mixture of 30 volumes of water and 70 volumes of acetonitrile (Mobile Phase B) with gradient program; detector wavelength 220 nm and column temperature 30 °C. The developed method was extensively validated according to ICH guidelines.Results: Good linearity was observed for isosulfan blue, impurity-A, impurity-B and impurity-C, linearity was calculated from loq Level To 150%with respect to specification level. The correlation coefficient R = 0.999 was proved and showed that the method is robust. The limit of detection of isosulfan blue, impurity-A, impurity-B and impurity-C were found to be 0.010%, 0.015%, 0.030% and 0.0075 % respectively and limit of quantitation of isosulfan blue, impurity-A, impurity-B and impurity-C were found to be 0.030%, 0.030%, 0.045% and 0.015% respectively for 2ml injection volume. The percentage recovery of isosulfan blue and its related impurities were ranged from 94.0 to 108.0 in bulk drug samples. Isosulfan blue sample solution and mobile phase were found to be stable for at least 72 h. The proposed method was found to be suitable and accurate for the quantitative determination of impurity-A, impurity-B, impurity-C and other unknown impurities in isosulfan blue drug substances.Conclusion: A new, simple and rapid method has been developed and validated for separation and determination of impurity-A, impurity-B, impurity-C and unknown impurities of isosulfan blue by the reverse-phase liquid chromatographic method. Analytical method was developed and validated as per ICH guidelines.The developed method can be used for the quantitative determination of impurity A, impurity B, impurity C and unknown impurities in isosulfan blue drug substances in pharmaceutical industry.

Presence of Ki-67, a nuclear protein, is typically used to measure cell proliferation. The quantification of the Ki-67 proliferation index is performed visually by the pathologist; however, this is subject to inter- and intra-reader variability. Automated techniques utilizing digital image analysis by computers have emerged. The large variations in specimen preparation, staining, and imaging as well as true biological heterogeneity of tumor tissue often results in variable intensities in Ki-67 stained images. These variations affect the performance of currently developed methods. To optimize the segmentation of Ki-67 stained cells, one should define a data dependent transformation that will account for these color variations instead of defining a fixed linear transformation to separate different hues. To address these issues in images of tissue stained with Ki-67, we propose a methodology that exploits the intrinsic properties of CIE L ∗ a ∗ b ∗ color space to translate this complex problem into an automatic entropy based thresholding problem. The developed method was evaluated through two reader studies with pathology residents and expert hematopathologists. Agreement between the proposed method and the expert pathologists was good (CCC = 0.80).

Emotional design for smart product-service system: A case study on smart beds

The aim of study was to develop a suitable analytical method for simultaneous estimation of levodopa, carbidopa and 3-O-methyl dopa in rat plasma. Chromatographic separation of plasma samples was achieved using a reverse-phase C18 column. The mobile phase used consisted of a mixture of methanol and phosphate buffer (10 mM, pH 3.50) in the ratio of 90:10 v/v. All analytes were estimated by electrochemical detection at +800 mV. The developed method has been validated as per the standard guidelines. Precision study results were found to be satisfactory, with percentage relative standard deviation for repeatability and intermediate precision <3.96 and 6.56%, respectively, for all analytes detected in rat plasma. The developed method in rat plasma was found to be simple, rapid, accurate, precise and specific. The proposed method has been successfully applied for analysis of rat plasma samples obtained during an oral pharmacokinetic study of sustained release pellets of levodopa and carbidopa in rats. Copyright © 2016 John Wiley & Sons, Ltd.

A liquid chromatographic method based on determining of the amount of lactic acid was developed to detect milk adulteration with neutralizers. The developed method can be applied to milk with pH values within the regular range of 6.5–6.7 that is suspected of being neutralised. Determination of lactic acid was carried out in milk acidified with lactic acid and neutralised with sodium hydroxide to simulate the adulteration. The validation parameters showed high linearity (R2 > 0.99), good precision (relative standard deviation ≤ 0.123%) and high sensibility (limit of detection 0.1 mg/L and limit of quantification 1 mg/L). The proposed method was applied to bacterially acidified and subsequently neutralised milk and detected a content of lactic acid of approximately 40 mg/100 mL in milk slightly acidified to pH 6.4. The developed method is simple, fast, precise and suitable for detecting the addition of hydroxides in sour milk. In parallel, the sodium content was determined in the same sodium hydroxide neutralised samples, but the addition of a small amount of this alkali does not affect the natural variation of sodium in milk.