Probability distribution free multilevel sampling pattern design for single pixel cameras

Ambulance location problem is a key issue in Emergency Medical Service (EMS) system, which is to determine where to locate ambulances such that the emergency calls can be responded efficiently. Most related researches focus on deterministic problems or assume that the probability distribution of demand can be estimated. In practice, however, it is difficult to obtain perfect information on probability distribution. This paper investigates the ambulance location problem with partial demand information; i.e., only the mean and covariance matrix of the demands are known. The problem consists of determining base locations and the employment of ambulances, to minimize the total cost. A new distribution-free chance constrained model is proposed. Then two approximated mixed integer programming (MIP) formulations are developed to solve it. Finally, numerical experiments on benchmarks (Nickel et al., 2016) and 120 randomly generated instances are conducted, and computational results show that our proposed two formulations can ensure a high service level in a short time. Specifically, the second formulation takes less cost while guaranteeing an appropriate service level.

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Evaluation of simple quantile estimation functions for modeling forest diameter distributions in even-aged stands of interior Douglas-fir

Canadian Journal of Forest Research ◽

10.1139/x93-293 ◽

1993 ◽

Vol 23 (11) ◽

pp. 2376-2382 ◽

Cited By ~ 1

Author(s):

James D. Newberry ◽

James A. Moore ◽

Lianjun Zhang

Keyword(s):

Probability Distribution ◽

Order Statistics ◽

Estimation Method ◽

Douglas Fir ◽

Quantile Estimation ◽

Distribution Free ◽

Inland Northwest ◽

Distribution Parameters ◽

Solving Equations ◽

Diameter Distributions

The method of percentiles usually involves simultaneously solving equations for probability distribution parameters as functions of sample-based estimates of the appropriate quantiles. Eight simple distribution-free methods for estimating quantiles from sample-based order statistics were evaluated empirically using even-aged Douglas-fir (Pseudotsugamenziesii var. glauca (Beissn.) Franco) diameter distributions from the Inland Northwest. Two methods, calculated by weighting adjacent order statistics, consistently gave the best results for both the Weibull and Johnson's SB distributions. Certain distributional shapes were also evaluated to determine if they influenced the quantile estimation method. Although some influence was detected, the best methods were usually best across all categories.

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Wideband Sparse Signal Acquisition Based on Serial Multi-Coset Sampling

Mathematical Problems in Engineering ◽

10.1155/2018/9208568 ◽

2018 ◽

Vol 2018 ◽

pp. 1-7

Author(s):

Changjian Liu ◽

Houjun Wang

Keyword(s):

Sampling Rate ◽

Binary Sequence ◽

Sampling Technique ◽

Signal Acquisition ◽

Sensing Matrix ◽

Pattern Design ◽

Analog To Digital ◽

Reconstruction Performance ◽

Sequence Generator ◽

Sampling Pattern

Traditional parallel multi-coset sampling (MCS), which has several sub-Analog-to-Digital-Converters (sub-ADCs) working parallelly, is an attractive sub-Nyquist sampling technique for wideband sparse signals. However, the mismatch among sub-ADCs in traditional parallel MCS, such as bias, gain, and timing skew mismatch, degrades the signal acquisition performance greatly. In this paper, a serial MCS scheme based on clocking single ADC with nonuniform clock is proposed. The nonuniform sampling clock is generated by a pseudo-random binary sequence generator. An additional Sample/Hold (S/H) is used to improve the analog bandwidth of the serial MCS. Moreover, universal sampling pattern is designed for the proposed serial MCS. The sampling pattern design should not only maximize the Kruskal rank of compressed sensing matrix but also take the ADC’s sub-Nyquist sampling rate into consideration. Numeral experiments are presented demonstrating that the mismatch among sub-ADCs in traditional parallel MCS degrades the reconstruction performance greatly, and the proposed serial MCS can avoid the mismatch tactfully.

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