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Individuals’ driving behavior data are becoming available widely through Global Positioning System devices and on-board diagnostic systems. The incoming data can be sampled at rates ranging from one Hertz (or even lower) to hundreds of Hertz. Failing to capture substantial changes in vehicle movements over time by “undersampling” can cause loss of information and misinterpretations of the data, but “oversampling” can waste storage and processing resources. The purpose of this study is to empirically explore how micro-driving decisions to maintain speed, accelerate or decelerate, can be best captured, without substantial loss of information.

This study creates a set of indicators to quantify the magnitude of information loss (MIL). Each indicator is calculated as a percentage to index the extent of information loss (EIL) in different situations. An overall information loss index named EIL is created to combine the MIL indicators. Data from a driving simulator study collected at 20 Hertz are analyzed (N = 718,481 data points from 35,924 s of driving tests). The study quantifies the relationship between information loss indicators and sampling rates.

The results show that marginally more information is lost as data are sampled down from 20 to 0.5 Hz, but the relationship is not linear. With four indicators of MILs, the overall EIL is 3.85 per cent for 1-Hz sampling rate driving behavior data. If sampling rates are higher than 2 Hz, all MILs are under 5 per cent for importation loss.

This study contributes by developing a framework for quantifying the relationship between sampling rates, and information loss and depending on the objective of their study, researchers can choose the appropriate sampling rate necessary to get the right amount of accuracy.

Health care insurance companies often conduct sample surveys of health plan members. Survey purposes include: consumer satisfaction with the plan and members’ health status, functional status, health literacy and/or health services utilization outside of the plan. Vendors or contractors typically conduct these surveys for insurers. Survey results may be used for plans’ accreditation, evaluation, quality improvement and/or marketing. This article describes typical sampling plans and data analysis strategies used in these surveys, showing how these methods may result in biased estimators of population parameters (e.g. percentage of plan members who are satisfied). Practical suggestions are given to improve these surveys: alternate sampling plans, increasing the response rate, component calculation for the survey response rate, weighted analyses, and adjustments for unit non-response. Since policy, regulation, accreditation, management and marketing decisions are based, in part, on results from these member surveys, these important and numerous surveys need to be of higher quality.

The purpose of this paper is to present a compressed sensing (CS)-based sampling system for ultra-wide-band (UWB) signal. By exploiting the sparsity of signal, this new sampling system can sub-Nyquist sample a multiband UWB signal, whose unknown frequency support occupies only a small portion of a wide spectrum.

A random Rademacher sequence is used to sense the signal in the frequency domain, and a matrix constructed by Hadamard basis is used to compress the signal. The probability of reconstruction is proved mathematically, and the reconstruction matrix is developed in the frequency domain.

Simulation results indicate that, with an ultra-low sampling rate, the proposed system can capture and reconstruct sparse multiband UWB signals with high probability. For sparse multiband UWB signals, the proposed system has potential to break through the Shannon theorem.

Different from the traditional sub-Nyquist techniques, the proposed sampling system not only breaks through the limitation of Shannon theorem but also avoids the barrier of input bandwidth of analog-to-digital converters (ADCs).

Sediment measurement is usually accessible on a periodic or distinct basis. The measurement of sediment (suspended and bedload), especially in the field, is vital in keeping essential data of sediment transport and deposition. Various techniques for measuring sediment have been used over time each with its merits and demerits. The techniques discussed in this paper for suspended sediment include bottle, acoustic, pump, laser diffraction, nuclear and optical. Other techniques for bedload measurement are; River bedload trap (RBT), CSU/FU bedload trap, Helley–Smith, Polish Hydrological Services (PIHM) device, pit and trough, vortex tube, radioactive traces and bedload–surrogate technologies. However, the choice of technique depends on multiple factors ranging from budget constraint, availability of equipment, manpower and data requirement. The purpose of this paper is to present valuable information on selected techniques used in sediment measurement, to aid researchers/practitioners in the choice of sediment measurement technique.

This paper presents a general review of selected field techniques used in sediment measurement (suspended and bedload). Each techniques mode of operation, merits and demerits are discussed.

This paper highlights that each technique has its peculiar merits and demerits. However, two techniques are generally preferred over others; the bottle sampling and the Helley–Smith sampler for measuring suspended and bedload sediment. This is because the applicability of these techniques is quite widespread and time-tested.

This review paper provides an in-depth description and comparison of selected existing field sediment measurement techniques. The objective is to ease decision-making about the choice of technique, as well as to identify the suitability and applicability of the chosen technique.

This paper aims to investigate the impact of in‐store sample promotions of food products on consumer trial and purchasing behavior. The authors investigate differences in the trial rate for free samples across different products and consumer types, as well as the impact of sampling on product and category purchase incidence. The results of this study are relevant for retailers and manufacturers who invest in in‐store free sample promotions.

The authors use data from a field study, which leveraged an actual free‐sample program implemented by a US grocery store chain. Data was collected on six different products promoted by in‐store free samples over six different weekends. The data collected included consumers' trial and purchasing behavior with respect to the free sample, as well as their attitudes towards the free sample that day and free sample promotions in general.

Free sampling is very effective in inducing trial, especially among lower educated consumers. For consumers who are planning to buy the product in the promoted category, free sampling can encourage switching from the planned to the promoted brand. For consumers who do not have such previous plans, free sampling can “draw“ them into the category and encourage category purchase. Samplers' interactions with the person distributing the sample or with other samplers at the scene also seem to boost post‐sample purchase incidence.

Despite the importance of free samples as a promotional tool, few studies have examined consumer trial and purchasing behavior with respect to in‐store free samples. This paper presents one of the first known field studies that examines this topic.

Acceptance sampling plans are designed to decide about acceptance or rejection of a lot of products on the basis of sample drawn from it. Accelerating the life test helps in obtaining information about the lifetimes of high reliability products quickly. The purpose of this paper is to formulate an optimum time censored acceptance sampling plan based on ramp-stress accelerated life test (ALT) for items having log-logistic life distribution. The log-logistic life distribution has been found appropriate for highly reliable components such as power system components and insulating materials.

The inverse power relationship has been used to model stress-life relationship. It is meant for analyzing data for which the accelerated stress is nonthermal in nature, and frequently used as an accelerating stress for products such as capacitors, transformers, and insulators. The method of maximum likelihood is used for estimating design parameters. The optimal test plan is obtained by minimizing variance of test-statistic that decides on acceptability or rejectibility of lot. The optimal test plan finds optimal sample size, stress rates, sample proportion allocated to each stress and lot acceptability constant such that producer’s risk and consumer’s risk is satisfied.

Asymptotic variance plays a pivotal role in determining the sample size required for a sampling plan for deciding the acceptance/rejection of a lot. The sample size is minimized by optimally designing a ramp-stress ALT so that the asymptotic variance is minimized.

The model suggested is of use to quality control and reliability engineers dealing with highly reliable items.

Very large-scale integration (VLSI) digital signal processing became very popular and is predominantly used in several emerging applications. The optimal design of multirate filter with improvement in performance parameters such as less area, high speed and less power is the challenging task in most of the signal processing applications. This study aims to propose several effective multirate filter structures to accomplish sampling rate conversion.

The multirate filter structures considered in this work are polyphase filter and coefficient symmetry-based finite impulse response filter. The symmetry scheme particularly brings down the complexity to significant extent. To bring improvement in speed, delay registers are inserted at appropriate path with the help of pipelining and retiming scheme.

In this paper, the three tasks have been considered. First, the polyphase coefficient symmetry and modified polyphase (MP) structure is designed. Second, the pipelining is applied to the polyphase structure and the obtained results are compared with the polyphase structure. In third, retiming is applied to the polyphase structure and the performance comparison is carried out. The structures are realized for various orders, and the comparative analysis is carried out with the filter order N = 12, 30, 42, 8, 11 and 24 and the results are stated. The performance of all the accomplished structures is analyzed using Altera Quartus with the family cyclone II, device EP2C70F672C6. The results show that the multirate filter using pipelining and retiming offers better performance when examining with the conventional structures. Retimed and pipelined MP structure achieves a speed enhancement of about 33.81% when examining with the conventional polyphase (CP) structure with retiming and pipelining for N = 24 and M = 5. Likewise, the 2/3 structure of pipelined coefficient symmetry approach offers area reduction of about 54.76% over 2/3 structure of pipelined polyphase approach for N = 30 with little reduction in power. The fine grain pipelined and retimed MP structure with N = 11 and M = 3 avails critical path delay reduction of about 28.15% when examining with the corresponding fine grain pipelined and retimed CP structure.

The proposed distinct structures offer better alternative to conventional structures because of the symmetric coefficients, performance enhancement using pipelining and retiming based rate conversion structures. The suggested structures can be used for achieving different rates in software radios.

Evidence for adverse impact in applied, organizational settings can often depend on application of the “four-fifths rule.” We analyze the arithmetic four-fifths rule, its operationalization, and related statistical tests. We note that the rule has intuitive appeal and has arithmetic directness. On the other hand, the four-fifths rule contains many ambiguities because of the manner in which it is defined, as well as its use in practice. One purpose of this article is to discuss the arithmetic and statistical facets of the definition. A related purpose of this article is to demonstrate where the ambiguities (and possibly unintended consequences) with the four-fifths rule might arise when numerical interpretations are invoked. Implications for future research and academic dialogues are then noted.