Статті в журналах: "Single Stage Sampling"

1

Boistard, Hélène, Hendrik P. Lopuhaä, and Anne Ruiz-Gazen. "Functional central limit theorems for single-stage sampling designs." Annals of Statistics 45, no. 4 (August 2017): 1728–58. http://dx.doi.org/10.1214/16-aos1507.

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2

Overall, John E., and Robert S. Atlas. "Comparison of a Two-Stage and Three-Stage Interim-Analysis Procedure." Psychological Reports 71, no. 1 (August 1992): 3–14. http://dx.doi.org/10.2466/pr0.1992.71.1.3.

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A statistical model for combining p values from multiple tests of significance is used to define rejection and acceptance regions for two-stage and three-stage sampling plans. Type I error rates, power, frequencies of early termination decisions, and expected sample sizes are compared. Both the two-stage and three-stage procedures provide appropriate protection against Type I errors. The two-stage sampling plan with its single interim analysis entails minimal loss in power and provides substantial reduction in expected sample size as compared with a conventional single end-of-study test of significance for which power is in the adequate range. The three-stage sampling plan with its two interim analyses introduces somewhat greater reduction in power, but it compensates with greater reduction in expected sample size. Either interim-analysis strategy is more efficient than a single end-of-study analysis in terms of power per unit of sample size.

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3

Qian, Hanxiang, Peng Wu, Bei Sun, and Shaojing Su. "AGS-SSD: Attention-Guided Sampling for 3D Single-Stage Detector." Electronics 11, no. 14 (July 20, 2022): 2268. http://dx.doi.org/10.3390/electronics11142268.

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3D object detection based on LiDAR point cloud has always been challenging. Existing point cloud downsampling approaches often use heuristic algorithms such as farthest point sampling (FPS) to extract the features from a massive raw point cloud. However, FPS has disadvantages such as low operating efficiency and inability to sample key areas. This paper presents an attention-guided downsampling method for point-cloud-based 3D object detection, named AGS-SSD. The method contains two modules: PEA (point external attention) and A-FPS (attention-guided FPS). PEA explores the correlation between the data and uses the external attention mechanism to extract the semantic features in the set abstraction stage. The semantic information, including the relationship between the samples, is sent to the candidate point generation module as context points. A-FPS weighs the point cloud according to the generated attention map and samples the foreground points with rich semantic information as candidate points. The experimental results show that our method achieves significant improvements with novel architectures against the baseline and runs at 24 frames per second for inference.

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4

JONES, WILLIAM, KATHY MORRING, PHILIP MOREY, and WILLIAM SORENSON. "Evaluation of the Andersen Viable Impactor for Single Stage Sampling." American Industrial Hygiene Association Journal 46, no. 5 (May 1, 1985): 294–98. http://dx.doi.org/10.1080/15298668591394833.

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5

Hoogduin, Lucas A., Thomas W. Hall, and Jeffrey J. Tsay. "Modified Sieve Sampling: A Method for Single- and Multi-Stage Probability- Proportional-to-Size Sampling." AUDITING: A Journal of Practice & Theory 29, no. 1 (May 1, 2010): 125–48. http://dx.doi.org/10.2308/aud.2010.29.1.125.

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SUMMARY: Widely used probability-proportional-to-size (PPS) selection methods are not well adapted to circumstances requiring sample augmentation. Limitations include: (1) an inability to augment selections while maintaining PPS properties, (2) a failure to recognize changes in census stratum membership which result from sample augmentation, and (3) imprecise control over line item sample size. This paper presents a new method of PPS selection, a modified version of sieve sampling which overcomes these limitations. Simulations indicate the new method effectively maintains sampling stratum PPS properties in single- and multi-stage samples, appropriately recognizes changes in census stratum membership which result from sample augmentation, and provides precise control over line item sample sizes. In single-stage applications the method provides reliable control of sampling risk over varied tainting levels and error bunching patterns. Tightness and efficiency measures are comparable to randomized systematic sampling and superior to sieve sampling.

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6

Wen, Miin-Jye, Li-Ching Huang, and Junjiang Zhong. "Single-stage sampling procedure of the t best populations under heteroscedasticity." Communications in Statistics - Theory and Methods 46, no. 18 (June 2, 2017): 9265–73. http://dx.doi.org/10.1080/03610926.2016.1206935.

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7

Thunyasirinon, Chuleewan, Pipat Sribenjalux, and Paradee Chuaybamroong. "Comparison of a Six-Stage and a Single Stage Viable Andersen Impactor (N6) for Airborne Microbe Sampling." Khon Kaen University Journal (Graduate Studies) 07, no. 3 (July 1, 2007): 107–17. http://dx.doi.org/10.5481/kkujgs.2007.07.3.11.

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8

Chen, Demin, Wei Long, Yanyan Li, and Rui Zhang. "Study on Change Rules of Factors Affecting Gas Loss during Coalbed Air Reverse Circulation Sampling." Advances in Civil Engineering 2021 (April 20, 2021): 1–15. http://dx.doi.org/10.1155/2021/5550726.

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The gas loss in sampling is the root of coalbed gas content measurement error. The pressure and particle size have a significant impact on the gas loss. Using the self-developed coal particle pneumatic pipeline transportation experimental system, this study investigated the pressure and particle size changes in the sampling pipeline. It is found that the sampling process can be divided into four stages: no flow field stage, sample outburst stage, stable conveying stage, and tail purging stage. The extreme pressure in the sampling pipeline appears at the sample outburst stage; and the pressure in the pipeline has levelled off after sharp decrease in the stable conveying stage. It is also found that the extreme pressure increases first and then decreases with the increase of particle size. The duration of outburst stage is negatively correlated with particle size, and that of stable conveying stage is positively correlated with particle size. In addition, the results show that the loss rate of 1–3 mm particles is the smallest after the test but that particles less than 1 mm increase by about two times and particles greater than 3 mm decrease by more than three times. The study also shows that the particle size distribution of coal samples is a single peak with left skew distribution, and the gas reverse circulation sampling test does not change the location of the peak but makes it higher and sharper. The single size coal sample is more likely to collide than the mixture. This study can help to advance the understanding of impact factors on gas loss during reverse circulation sampling.

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9

Valliant, Richard. "Some Prediction Properties of Balanced Half-Sample Variance Estimators in Single-Stage Sampling." Journal of the Royal Statistical Society: Series B (Methodological) 49, no. 1 (September 1987): 68–81. http://dx.doi.org/10.1111/j.2517-6161.1987.tb01427.x.

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10

Temesgen, H. "Evaluation of sampling alternatives to quantify tree leaf area." Canadian Journal of Forest Research 33, no. 1 (January 1, 2003): 82–95. http://dx.doi.org/10.1139/x02-159.

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High within- and among-tree crown variation have contributed to the difficulty of tree-crown sampling and single-tree leaf area (area available for photosynthesis) estimation. Using reconstructed trees, simulations were used to compare five sampling designs for bias, mean square error (MSE), and distribution of the estimates. All sampling designs showed nearly zero bias. For most sample trees, stratified random sampling resulted in the lowest MSE values, followed by ellipsoidal, two-stage systematic, simple random, and then by two-stage unequal probability sampling. The poor performance of two-stage unequal probability sampling can be ascribed to the unequal probability of inclusion of first-order branches and twigs.

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11

Arul, S. Deva, and K. Rebecca Jebaseeli Edna. "Mixed Sampling Product Control for Costly or Destructive Items." Journal of Mathematical Sciences & Computer Applications 1, no. 3 (June 10, 2017): 85–94. http://dx.doi.org/10.5147/jmsca.v1i3.95.

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This paper presents the derivation of operating characteristics function and associated measures of performance of mixed sampling Plans for costly or destructive items. The first stage is concerned with single sample variable inspection and in the second stage modified Chain Sampling inspection is recommended. If the first stage inspection of mixed plans does not lead to acceptance of the batch or lot then the second stage becomes more important. In the second stage of mixed plans, it is advisable to have small sample size for costly or destructive items. Therefore, in the second stage, the modified chain sampling plan which always utilizes the past lot inspection results in order to achieve very small sample size is taken into consideration. The economic or cost-effective of the sampling plans is measured through Average Sample Number which is smaller compared to any other mixed sampling plans. Designing procedure is given and tables are constructed to facilitate easy application in the production industries.

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12

Valentine, H. T., J. H. Gove, and T. G. Gregoire. "Monte Carlo approaches to sampling forested tracts with lines or points." Canadian Journal of Forest Research 31, no. 8 (August 1, 2001): 1410–24. http://dx.doi.org/10.1139/x01-080.

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Several line- and point-based sampling methods can be employed to estimate the aggregate dimensions of trees standing on a forested tract or pieces of coarse woody debris lying on the forest floor. Line methods include line intersect sampling, horizontal line sampling, and transect relascope sampling; point methods include variable- and fixed-radius plot sampling, and point relascope sampling. We demonstrate that the line methods can be interpreted as applications of importance sampling and that point methods can be interpreted as two-stage applications of importance sampling and crude Monte Carlo. Interestingly, each of the line methods also can be implemented as a point method. Operationally, the two stages of a point method effectively reduce to a single stage. Estimators of target parameters are derived from the Monte Carlo approach for all six methods. Two new methods of estimating cross-sectional areas of slanted or tilted log-shaped objects are suggested for use in line intersect sampling. Boundary problems also are discussed.

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13

Nicoletti, João V. M., Marcello R. A. Franchi, Anamari V. de A. Motomiya, Wagner R. Motomiya, and José P. Molin. "Efficiency and quality of soil sampling according to a sampling tool." Revista Brasileira de Engenharia Agrícola e Ambiental 27, no. 6 (June 2023): 480–86. http://dx.doi.org/10.1590/1807-1929/agriambi.v27n6p480-486.

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ABSTRACT Soil sampling is a fundamental stage for recommending agricultural correctives and fertilizers, estimating the nutritional demands of plants, and consequently maximizing productivity. Therefore, this study aimed to assess the performance of three soil samplers in different management systems in terms of sample quality and operational efficiency. A completely randomized experimental design was used in a factorial scheme. Three samplers and two sampling depths (3 × 2) were used with four replicates. At each sampling location, eight single samples were taken at a varying sampling depth of 0.0-0.2 and 0.2-0.4 m, and the collection time was recorded. Samples were analyzed for chemical attributes and granulometry. Statistically significant differences were observed for specific attributes (organic matter, K, Ca, CEC, pH, and S). In terms of operational efficiency, the hydraulic sampler was more efficient than the other samplers, being three times faster than the combustion drill and six times faster than the manual probe. Thus, it is suitable and reliable for soil sampling purposes.

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14

Luca, Stijn, Johan Vandercappellen, and Johan Claes. "A web-based tool to design and analyze single- and double-stage acceptance sampling plans." Quality Engineering 32, no. 1 (August 26, 2019): 58–74. http://dx.doi.org/10.1080/08982112.2019.1641207.

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15

Gallagher, Michael, and A. R. Unwin. "Electoral Distortion under STV Random Sampling Procedures." British Journal of Political Science 16, no. 2 (April 1986): 243–53. http://dx.doi.org/10.1017/s0007123400003902.

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This Note will discuss the impact of random sampling at elections conducted under the single transferable vote (STV) electoral system in multi-member constituencies in the Republic of Ireland. STV, partly because of its popularity among electoral reformers, has received considerable theoretical scrutiny. It has been given an ‘intermediate’ rating in recent assessment of a number of electoral systems, and dismissed as a ‘perverse social choice function’ because it is subject to non-monotonicity. This shortcoming is also mainly responsible for the low degree of acceptance accorded to it by Brams and Fishburn. Nurmi concludes that STV (like other multi-stage systems) performs poorly, with regard to a number of criteria, in comparison with one-stage systems like approval voting. Black complains that STV ‘is a compound of minor complexities and is difficult to remember’. Others have discussed shortcomings in STV and suggested remedies which can be implemented where the counting of votes is entirely computerized.

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16

Wang, Shu Qiang, Hui Zhao, and Kang Wu. "DSP-Based Single-Stage Full Bridge Power Factor Correction Technology Research." Advanced Materials Research 546-547 (July 2012): 326–31. http://dx.doi.org/10.4028/www.scientific.net/amr.546-547.326.

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This paper introduces a power factor correction (PFC) main circuit adopting novel full bridge topology, in which the clamped capacitor limits voltage stress on the switch tube, reduces output voltage ripple, and improves the response velocity; TMS320F2812 series DSP, produced by TI company, is used as the main control device in this system, and the DSP fixes the switch frequency at 20kps. It uses alternate sampling method to avoid the switching noise taken into the system. And then, both the validity of the theoretical analysis and the effectiveness of the control strategy are verified by the prototype test.

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17

Davies, Rhian Siân, Christian Smith, Gwenllian Edwards, Rachel Butler, Diane Parry, and Jason Francis Lester. "Impact of Cytological Sampling on EGFR Mutation Testing in Stage III-IV Lung Adenocarcinoma." Lung Cancer International 2017 (March 7, 2017): 1–5. http://dx.doi.org/10.1155/2017/9614938.

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Objectives. There have been advances in the identification and understanding of molecular subsets of lung cancer, defined by specific oncogenic aberrations. A number of actionable genetic alterations have been identified, such as the epidermal growth factor receptor (EGFR) mutation. We aimed to establish the reasons why patients were not undergoing EGFR mutation testing at the time of histological diagnosis. Methods. The records of 70 patients with advanced adenocarcinoma of the lung managed through a single multidisciplinary team at a single institution were reviewed. Data were collected on method of tumour sample collection, whether this was sent for EGFR testing, and the result. Results. Seventy patients were identified. In 21/25 (84%) cases, cytological sampling was sufficient for EGFR mutation analysis, compared with 40/45 (89%) cases with histological sampling. EGFR mutation testing was not carried out in 22/70 (31.4%) patients. There was insufficient tumour sample for EGFR testing in 9/22 (40.9%) patients. Other reasons for not testing included poor patient fitness and problems in the diagnostic pathway. Conclusions. In this series, cytological tumour sampling was not the predominant reason why cancers failed to have EGFR mutation status established.

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18

Huang, I. Ping, and Chiuh Cheng Chyu. "Designing Economic Inspection Sampling Procedure with Bayesian Approach." Advanced Materials Research 711 (June 2013): 683–88. http://dx.doi.org/10.4028/www.scientific.net/amr.711.683.

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This paper proposes a Bayesian inspection sampling model for single specification limit components with the objective of minimizing the expected total cost. The model assumes that the producer will undertake a two-stage Bayesian inspection process for the purchased lot: (1) determine the optimal sample size, and (2) after learning the sampling information, decide to either inspect all of the remainder or stop inspections. In particular, the paper studies the case where the quality characteristic of the component has a location-shifting exponential distribution with an unknown mean. Using gamma distribution as the conjugate prior, a closed form decision criterion for the second stage inspection process can be derived, and the computational complexity will be greatly reduced. The attribute sampling model under the same probability distribution and cost structure is also deduced and compared with the original model. Finally, an electronic lighting device example is used to illustrate the proposed model, and the effects of the model parameters are discussed.

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19

LEVY, PAUL S., ELENA S. H. YU, WILLIAM T. LIU, MING-YUAN ZHANG, ZHENG-YU WANG, SIU CHI WONG, and ROBERT KATZMAN. "A variation on single-stage cluster sampling used in a survey of elderly people in Shanghai." International Journal of Epidemiology 17, no. 4 (1988): 931–33. http://dx.doi.org/10.1093/ije/17.4.931-a.

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20

Perfler, R., and R. Haberl. "Actual Experiences with the Use of Reed Bed Systems for Wastewater Treatment in Single Households." Water Science and Technology 28, no. 10 (November 1, 1993): 141–48. http://dx.doi.org/10.2166/wst.1993.0222.

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Within a longterm project from 1991 to 1996 investigations on the use of constructed wetlands for pollution control in rural areas will be carried out especially regarding the rather strict limiting values for nutrient elimination. The actual discussion is also relevant for very small systems applied to single households. Three reed bed systems - one vertical flow, single stage; one vertical flow double stage (parallel and in-series operation possible); one horizontal flow, double stage - have been constructed in 1991 regarding all the new experiences on optimizing this technology. Some results of inlet and outlet sampling and from sampling points within the bed, of tracer experiments and microbiological and virological testing are presented. In addition a short review on the installation costs is given. In general the experiences of one year of operation seem to prove the opportunity to meet the tightened limits by waste water treatment in constructed wetlands.

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21

Catranis, Catharine M., Susan E. Anagnost, Lianjun Zhang, Shuang Zhou, Analie Fernando, Shannon Morey, and C. J. K. Wang. "A new sub-sampling method for analysis of air samples collected with the Andersen single-stage sampler." Aerobiologia 22, no. 3 (September 2006): 177–84. http://dx.doi.org/10.1007/s10453-006-9030-2.

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22

Choi, Eujeong, Shinyoung Kwag, Jeong-Gon Ha, and Daegi Hahm. "Development of a Two-Stage DQFM to Improve Efficiency of Single- and Multi-Hazard Risk Quantification for Nuclear Facilities." Energies 14, no. 4 (February 15, 2021): 1017. http://dx.doi.org/10.3390/en14041017.

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The probabilistic safety assessment (PSA) of a nuclear power plant (NPP) under single and multiple hazards is one of the most important tasks for disaster risk management of nuclear facilities. To date, various approaches—including the direct quantification of the fault tree using the Monte Carlo simulation (DQFM) method—have been employed to quantify single- and multi-hazard risks to nuclear facilities. The major advantage of the DQFM method is its applicability to a partially correlated system. Other methods can represent only an independent or a fully correlated system, but DQFM can quantify the risk of partially correlated system components by the sampling process. However, as a sampling-based approach, DQFM involves computational costs which increase as the size of the system and the number of hazards increase. Therefore, to improve the computational efficiency of the conventional DQFM, a two-stage DQFM method is proposed in this paper. By assigning enough samples to each hazard point according to its contribution to the final risk, the proposed two-stage DQFM can effectively reduce computational costs for both single- and multi-hazard risk quantification. Using examples of single- and multi-hazard threats to nuclear facilities, the effectiveness of the proposed two-stage DQFM is successfully demonstrated. Especially, two-stage DQFM saves computation time of conventional DQFM up to 72% for multi-hazard example.

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23

Han, Wensheng, Hong Zhu, Chenghui Qi, Jingsi Li, and Dengyin Zhang. "High-Resolution Representations Network for Single Image Dehazing." Sensors 22, no. 6 (March 15, 2022): 2257. http://dx.doi.org/10.3390/s22062257.

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Deep learning-based image dehazing methods have made great progress, but there are still many problems such as inaccurate model parameter estimation and preserving spatial information in the U-Net-based architecture. To address these problems, we propose an image dehazing network based on the high-resolution network, called DeHRNet. The high-resolution network originally used for human pose estimation. In this paper, we make a simple yet effective modification to the network and apply it to image dehazing. We add a new stage to the original network to make it better for image dehazing. The newly added stage collects the feature map representations of all branches of the network by up-sampling to enhance the high-resolution representations instead of only taking the feature maps of the high-resolution branches, which makes the restored clean images more natural. The final experimental results show that DeHRNet achieves superior performance over existing dehazing methods in synthesized and natural hazy images.

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24

Wood, Geoffrey B., and Harry V. Wiant Jr. "Comparison of point-3P and modified point-list sampling for inventory of mature native hardwood forest in southeastern New South Wales." Canadian Journal of Forest Research 22, no. 5 (May 1, 1992): 725–28. http://dx.doi.org/10.1139/x92-097.

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A modified form of point-list sampling is described for a forest inventory; apart from a preliminary reconnaissance survey, this sampling method requires a single visit to the field and ensures that the desired size of the second-stage sample is obtained. Results achieved in applying the method for inventory of 68 ha of mature hardwood forest in southeastern New South Wales are compared with those derived from a conventional point-3P (also known as point-Poisson) inventory of the area using an identical first-stage sample design. The total volume estimates for the two inventories were comparable. The precision of the point-3P inventory was slightly better (8.7% SE compared with 9.0%) but the cost was greater because 9 more than the desired number of trees (38) were selected in the second-stage sample. The advantages of modified point-list sampling are discussed and estimation formulae are presented.

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25

Wyatt, Robin J. "Estimating riverine fish population size from single- and multiple-pass removal sampling using a hierarchical model." Canadian Journal of Fisheries and Aquatic Sciences 59, no. 4 (April 1, 2002): 695–706. http://dx.doi.org/10.1139/f02-041.

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A hierarchical model is described for estimating population size from single- and multiple-pass removal sampling. The model is appropriate for two-stage sampling schemes, typified by surveys of riverine fish populations, in which multiple sites are surveyed, but a low number of passes are undertaken at each site. The model estimates the average population size within the target area from the raw catch data, and thus allows for differences in the sampling procedure at each site, such as including single-pass sampling. The model also uses the data from all sites to estimate the population size at each individual site. This results in generally improved precision for multiple-pass sites and provides comparable estimates from single-pass sites. A Bayesian approach is described for estimating the parameters of the hierarchical model using sampling importance resampling (SIR). An empirical Bayesian approach, which ignores prior uncertainty but is simpler to implement, is also described. Application of the hierarchical model is illustrated with electrofishing data for 0+ trout (Salmo trutta) in the River Inny, U.K.

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26

Wang, Xueqing, Diankun Zhang, Haoyu Niu, and Xiaojun Liu. "Segmentation Can Aid Detection: Segmentation-Guided Single Stage Detection for 3D Point Cloud." Electronics 12, no. 8 (April 10, 2023): 1783. http://dx.doi.org/10.3390/electronics12081783.

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Detecting accurate 3D bounding boxes from point cloud data plays an essential role in autonomous driving. However, improving performance requires more complex models, which come with high memory and computational cost. In this work, we design a Segmentation-Guided Auxiliary Network (SGAN) to improve the localization quality of detection. The points from different levels are concatenated to generate the multi-scale feature for the points used for prediction, i.e., candidate points. SGAN is jointly optimized by two tasks of candidate points—segmentation and center estimation—and it is only used in training and therefore introduces no extra computation in the inference stage. Furthermore, we consider that point-based detectors suffer from the outline points of sampling, so we explore the correlation between the data and propose the Point Cloud External Attention (PCEA) to extract the semantic features with a low memory cost. Our method SGSSD achieves a large margin against the baseline on the KITTI and Waymo datasets, and it runs at 25 FPS for inference on the KITTI test set with a single NVIDIA RTX 3090.

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Villordon, Arthur, Don LaBonte, and Julio Solis. "Using a Scanner-based Minirhizotron System to Characterize Sweetpotato Adventitious Root Development during the Initial Storage Root Bulking Stage." HortScience 46, no. 3 (March 2011): 513–17. http://dx.doi.org/10.21273/hortsci.46.3.513.

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A scanner-based minirhizotron (MR) system detected initial adventitious root (AR) development associated with transplant establishment. The system also documented the transition of ARs into pencil roots (PRs) and, in some cases, storage roots (SRs). In general, the MR system underestimated destructive sampling-based (DS) estimates of newly initiated AR (NAR), PR, and SR counts. Angled or vertical single sampling tubes underestimated NAR count by 85% and 79%, respectively. Regardless of installation position, single tube-based measurements underestimated PR and SR count by 83% and 95%, respectively. However, it was found that two vertically installed tubes underestimated NAR count by only 48%. The potential ability of paired sampling tubes to discriminate NAR count differences in response to experimental treatments was confirmed in a simple rain shelter experiment. The paired MR and DS systems detected 83% and 56% reduction in NAR count among plots with rain shelters, respectively. However, it appeared that the presence of tubes interfered with SR formation of monitored AR segments. Despite this limitation, the results show the potential for incorporating MR systems in ongoing and future studies that aim to qualitatively and quantitatively document sweetpotato AR system response to agroclimatic variables and management interventions during the initial SR bulking stage.

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Seo, Min-Jae. "A Single-Amplifier Dual-Residue Pipelined-SAR ADC." Electronics 10, no. 4 (February 9, 2021): 421. http://dx.doi.org/10.3390/electronics10040421.

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This work presents a 12 bit 200 MS/s dual-residue pipelined successive approximation registers (SAR) analog-to-digital converter (ADC) with a single open-loop residue amplifier (RA). By using the inherent characteristics of the SAR conversion scheme, the proposed ADC sequentially generates two residue levels from the single RA, which eliminates the need for inter-stage gain-matching calibration. To convert the sequentially generated the two residues, a capacitive interpolating SAR ADC (I-SAR ADC) is also proposed. The I-SAR ADC is very compact because it consists of the one comparator, a CDAC, and control logic like a conventional SAR ADC. In addition, the I-SAR ADC needs no static power dissipation for the residue interpolation. A prototype ADC fabricated in a 40 nm CMOS technology occupies an active area of 0.026 mm2. At a 200 MS/s sampling-rate with the Nyquist input, the ADC achieves an SNDR (Signal-to-Noise distortion ratio) of 62.1 dB and 67.1 dB SFDR (Spurious-Free Dynamic Range), respectively. The total power consumed is 3.9 mW under a 0.9 V supply. Without any inter-stage mismatch calibration, the ADC achieve Walden Figure-of-Merit (FoM) of 19.0 fJ/conversion-step.

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Couperus, Anna Mareike, Fabian Schroeder, Robert Klukas, Johann Huber, Thomas Wittek, and Johannes R. Peham. "Influence of Different Lactation Stages on Circadian Rhythmicity of Metabolic Biomarkers in Dairy Cows: A Pilot Study." Animals 11, no. 4 (April 7, 2021): 1043. http://dx.doi.org/10.3390/ani11041043.

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Currently, subclinical metabolic imbalances at the individual cow and herd level are detected by measuring biomarkers in single blood samples. However, diurnal variations have not been fully described yet but need to be considered when sampling for a robust ad consistent analysis. The study describes the influence of lactation phases on circadian rhythms and diurnal variations for non-esterified fatty acids (NEFA), beta-hydroxybutyrate (BHB), total bilirubin (tBIL) and aspartate aminotransferase (AST) in dairy cows. In an observational pilot study, we used 16 clinically healthy Simmental dairy cows subdivided in four different lactation stages (dry-off, fresh, high and late lactating). Every cow was monitored for 24 h, with blood sampling and assessment of clinical parameters every 2 h. Time and lactation stage influence the concentration of the biomarkers NEFA, BHB and tBIL in serum. Further, circadian rhythmicity was found in high lactating cows for NEFA peaking at 5:39 am and BHB peaking at 4:20 pm. We suggest blood sampling for single-point measurements within three hours after the first feeding until two hours after the last feeding of the day. The results provide a new insight into the physiology of circadian rhythms in dairy cows and enable improved metabolic monitoring.

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Hogmire, Henry W., and Larry Crim. "Apple, Acaricide Evaluation, 1985." Insecticide and Acaricide Tests 11, no. 1 (January 1, 1986): 27. http://dx.doi.org/10.1093/iat/11.1.27.

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Abstract Acaricides were applied to 5 single-tree replications of 6-year-old trees in a randomized block design. The first application was made at either the tight cluster (8 Apr), pink (13 Apr) or petal fall (26 Apr) stage, depending upon treatment. All treatments received a second application on 5 Jul. Sprays were applied with a Myers V7710-5E02G hydraulic sprayer equipped with a handgun and operated at 200 psi. Treatment effectiveness was determined by sampling 20 leaves from the periphery of each tree (100/treatment), removing mites with a mite-brushing machine and counting active stages with a binocular microscope.

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31

Hamelin, Richard C., Mathieu Dusabenyagasani, and Khalid Et-touil. "Fine-Level Genetic Structure of White Pine Blister Rust Populations." Phytopathology® 88, no. 11 (November 1998): 1187–91. http://dx.doi.org/10.1094/phyto.1998.88.11.1187.

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The fine-level genetic structure of the white pine blister rust agent, Cronartium ribicola, was investigated by sampling multiple monokaryotic spermogonia directly on cankers in four eastern Canadian white pine (Pinus strobus) plantations and assessing genetic variability, using random amplified polymorphic DNA (RAPD) markers. Ninety-eight percent of the cankers surveyed contained a single DNA haplotype, suggesting spermogonia within cankers are the result of clonal reproduction. A single canker contained two haplotypes that were divided between the upper and lower parts of the canker, suggesting it represented two confluent cankers. In contrast, genotypic diversity was high among cankers. Thirty-seven haplotypes were found among forty-three cankers sampled, and an analysis of molecular variance indicated that 93% (P < 0.001) of the total genetic diversity was attributable to sampling of different cankers, strongly suggesting that multiple infections do not take place in the white pine blister rust pathosystem, i.e., a canker is the result of infection by a single genotype. This result is in contrast with the high level of genetic diversity previously reported among dikaryotic aecidia within cankers and is consistent with the hypothesis that variability in the aecidial stage is the result of outcrossing between resident spermogonia and alien spermatia. The genetic structure of the spermogonial stage, which is the vegetative extension of infection by basidiospores and, therefore, the indirect result of meiosis, was consistent with random mating; the observed genotypic diversity was not significantly different (P > 0.05) from the genotypic diversity expected under the assumption of panmixis. The results indicate that monokaryotic cankers can be genotyped by sampling a single unopened spermogonia per canker.

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32

Jia, Peng, and Fuxiang Liu. "Lightweight Feature Enhancement Network for Single-Shot Object Detection." Sensors 21, no. 4 (February 4, 2021): 1066. http://dx.doi.org/10.3390/s21041066.

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At present, the one-stage detector based on the lightweight model can achieve real-time speed, but the detection performance is challenging. To enhance the discriminability and robustness of the model extraction features and improve the detector’s detection performance for small objects, we propose two modules in this work. First, we propose a receptive field enhancement method, referred to as adaptive receptive field fusion (ARFF). It enhances the model’s feature representation ability by adaptively learning the fusion weights of different receptive field branches in the receptive field module. Then, we propose an enhanced up-sampling (EU) module to reduce the information loss caused by up-sampling on the feature map. Finally, we assemble ARFF and EU modules on top of YOLO v3 to build a real-time, high-precision and lightweight object detection system referred to as the ARFF-EU network. We achieve a state-of-the-art speed and accuracy trade-off on both the Pascal VOC and MS COCO data sets, reporting 83.6% AP at 37.5 FPS and 42.5% AP at 33.7 FPS, respectively. The experimental results show that our proposed ARFF and EU modules improve the detection performance of the ARFF-EU network and achieve the development of advanced, very deep detectors while maintaining real-time speed.

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Wu, Linkun, David San Segundo Bello, Philippe Coppejans, Jan Craninckx, Andreas Süss, Maarten Rosmeulen, Piet Wambacq, and Jonathan Borremans. "Analysis and Design of a CMOS Ultra-High-Speed Burst Mode Imager with In-Situ Storage Topology Featuring In-Pixel CDS Amplification." Sensors 18, no. 11 (October 30, 2018): 3683. http://dx.doi.org/10.3390/s18113683.

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This paper presents an in-situ storage topology for ultra-high-speed burst mode imagers, enabling low noise operation while keeping a high frame depth. The proposed pixel architecture contains a 4T pinned photodiode, a correlated double sampling (CDS) amplification stage, and an in-situ memory bank. Focusing on the sampling noise, the system level trade-off of the proposed pixel architecture is discussed, showing its advantages on the noise, power, and scaling capability. Integrated with an AC coupling CDS stage, the amplification is obtained by exploiting the strong capacitance to the voltage relation of a single NMOS transistor. A comprehensive noise model is developed for optimizing the trade-off between the area and noise. As a proof-of-concept, a prototype imager with a 30 µm pixel pitch was fabricated in a CMOS 130 nm technology. A 108-cell memory bank is implemented allowing dense layout and parallel readout. Two types of CDS amplification stages were investigated. Despite the limited memory capacitance of 10 fF/cell, the photon transfer curves of both pixel types were measured over different operation speeds up to 20 Mfps showing a noise performance of 8.4 e−.

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Riungu, Joy, Mariska Ronteltap, and Jules B. van Lier. "Volatile fatty acids build-up and its effect on E. coli inactivation during excreta stabilisation in single-stage and two-stage systems." Journal of Water, Sanitation and Hygiene for Development 8, no. 2 (March 19, 2018): 257–67. http://dx.doi.org/10.2166/washdev.2018.160.

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Abstract Digestion and co-digestion of faecal matter collected from urine diverting dehydrating toilet faeces (UDDT-F) and mixed organic market waste (OMW) was studied in single stage pilot scale mesophilic plug-flow anaerobic reactors at UDDT-F:OMW ratios 4:1 and 1:0. Escherichia coli inactivation and volatile fatty acids (VFA) build-up was monitored at sampling points located along the reactor profile. When applying UDDT-F:OMW ratio of 4:1 at 12% total solids (TS), E. coli inactivation achieved was 2.3 log times higher than that achieved in UDDT-F:OMW ratio of 1:0. In subsequent trials, a two-stage reactor was researched, applying a UDDT-F:OMW ratio of 4:1 and 10 or 12% TS slurry concentrations. Highest VFA concentrations of 16.3 ± 1.3 g/L were obtained at a pH of 4.9 in the hydrolysis/acidogenesis reactor, applying a UDDT-F:OMW ratio of 4:1 and 12% TS, corresponding to a non-dissociated (ND)-VFA concentration of 6.9 ± 2.0 g/L. The corresponding decay rate reached a value of 1.6 per day. In the subsequent methanogenic plug-flow reactor, a decay rate of 1.1 per day was attained within the first third part of the reactor length, which declined to 0.6 per day within the last third part of the reactor length. Results show that a two-stage system is an efficient way to enhance pathogen inactivation during anaerobic digestion.

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Luyckx, Fabrice, Bernhard Spitzer, Annabelle Blangero, Konstantinos Tsetsos, and Christopher Summerfield. "Selective Integration during Sequential Sampling in Posterior Neural Signals." Cerebral Cortex 30, no. 8 (March 7, 2020): 4454–64. http://dx.doi.org/10.1093/cercor/bhaa039.

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Abstract Decisions are typically made after integrating information about multiple attributes of alternatives in a choice set. Where observers are obliged to consider attributes in turn, a computational framework known as “selective integration” can capture salient biases in human choices. The model proposes that successive attributes compete for processing resources and integration is biased towards the alternative with the locally preferred attribute. Quantitative analysis shows that this model, although it discards choice-relevant information, is optimal when the observers’ decisions are corrupted by noise that occurs beyond the sensory stage. Here, we used electroencephalography (EEG) to test a neural prediction of the model: that locally preferred attributes should be encoded with higher gain in neural signals over the posterior cortex. Over two sessions, human observers judged which of the two simultaneous streams of bars had the higher (or lower) average height. The selective integration model fits the data better than a rival model without bias. Single-trial analysis showed that neural signals contralateral to the preferred attribute covaried more steeply with the decision information conferred by locally preferred attributes. These findings provide neural evidence in support of selective integration, complementing existing behavioral work.

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36

Molloy, Kevin, Laurent Denarie, Marc Vaisset, Thierry Siméon, and Juan Cortés. "Simultaneous system design and path planning: A sampling-based algorithm." International Journal of Robotics Research 38, no. 2-3 (July 9, 2018): 375–87. http://dx.doi.org/10.1177/0278364918783054.

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This paper addresses the simultaneous design and path-planning problem, in which features associated to the bodies of a mobile system must be selected to find the best design that optimizes its motion between two given configurations. Solving individual path-planning problems for all possible designs and selecting the best result would be straightforward only for very simple cases. We propose a more efficient approach that combines discrete (design) and continuous (path) optimization in a single stage. It builds on an extension of a sampling-based algorithm, which simultaneously explores the configuration-space costmap of all possible designs, aiming to find the best path-design pair. The algorithm filters out unsuitable designs during the path search, which breaks down the combinatorial explosion. Illustrative results are presented for relatively simple (academic) robotic examples, showing that even in these simple cases, the computational cost can be reduced by two orders of magnitude with respect to the naïve approach. A preliminary application to challenging problems in computational biology related to protein design is also discussed.

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37

Grabowski, Emily. "Comparison of coarse and fine sampling resolutions in vowel analysis." Journal of the Acoustical Society of America 152, no. 4 (October 2022): A60. http://dx.doi.org/10.1121/10.0015544.

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There are many researcher degrees of freedom in phonetic analyses, especially in that of segments such as vowels. The focus of this study is one such degree of freedom, governing how frequently measurements are taken for an individual token in the corpus. Choices for this stage of analysis include averaging formants (single measurement), taking point measurements (multiple measurements), or sampling continuously across the token (many measurements). Less-frequent measurements are convenient techniques compatible with many common statistical methods, but risk oversimplifying the patterns in the data. In this project, I compare point and continuous measurements using Generalized Additive Mixture Models (GAMMs) on speech corpus data. GAMMs are a generalized model that can flexibly parameterize both curves and points based on a combination of random and fixed effects. To compare different measurement frequencies, I quantify the benefit of additional measurements in terms of information gain and variance explained. I also address the modeling of multidimensional measurements and identify the degree to which issues of multidimensionality such as collinearity can be accounted for in GAMMs.

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38

Pascual, Leonor, Sara Pérez-Luz, Antonio Amo, Carmen Moreno, David Apraiz, and Vicente Catalán. "Detection ofLegionella pneumophilain bioaerosols by polymerase chain reaction." Canadian Journal of Microbiology 47, no. 4 (April 1, 2001): 341–47. http://dx.doi.org/10.1139/w01-012.

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Most studies focusing on detecting microorganisms in air by polymerase chain reaction (PCR) have used a liquid impinger to sample bioaerosols, mainly because a liquid sample is easy to be processed by PCR analysis. Nevertheless, the use of multiple-hole impactors for the analysis of bioaerosols by PCR has not been reported despite its great utility in culture analysis. In this study we have modified the impaction onto an agar surface sampling method to impaction onto a liquid medium using the MAS-100 air sampler (Merck) (single-stage multiple-hole impactor). To evaluate the recovery of airborne microorganisms of both sampling methods, a suspension containing Escherichia coli was artificially aerosolized and bioaerosols were collected onto Tergitol-7 agar and phosphate-buffered saline (PBS) with the MAS-100. A linear regression analysis of the results showed a strong positive correlation between both sampling methods (r = 0.99, slope 0.99, and y intercept 0.07). Afterwards, the method of impingement into a liquid medium was used to study airborne Legionella pneumophila by PCR. A total of 64 samples were taken at a wastewater treatment plant, a chemical plant, and an office building and analyzed by culture and PCR. Results showed that three samples were positive both by PCR and plate culture, and that nine samples negative by plate culture were positive by PCR, proving that L. pneumophila was present in bioaerosols from these three different environments. The results demonstrate the utility of this single-stage multiple-hole impactor for sampling bioaerosols, both by culture and by PCR.Key words: Legionella pneumophila, bioaerosols, PCR, multiple-hole impactor.

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Yan, Bo, Na Xu, Wenbo Zhao, Muqing Li, and Luping Xu. "An Efficient Extended Targets Detection Framework Based on Sampling and Spatio-Temporal Detection." Sensors 19, no. 13 (July 1, 2019): 2912. http://dx.doi.org/10.3390/s19132912.

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Excellent performance, real-time and low memory requirement are three vital requirements for target detection in high resolution marine radar system. Unfortunately, many current state-of-the-art methods merely achieve excellent performance when coping with highly complex scenes. In fact, a common problem is that real-time processing, low memory requirement and remarkable detection ability are difficult to coordinate. To address this issue, we propose a novel detection framework which bases its principle on sampling and spatiotemporal detection. The framework consists of two stages, coarse detection and fine detection. Sampling-based coarse detection is designed to guarantee the real-time processing and low memory requirements by locating the area where targets may exist in advance. Different from former detection methods, multi-scan video data are utilized. In the stage of fine detection, the candidate areas are grouped into three categories: single target, dense targets and sea clutter. Different approaches for processing the different categories are implemented to achieve excellent performance. The superiority of the proposed framework beyond state-of-the-art baselines is well substantiated in this work. Low memory requirement of the proposed framework was verified by theoretical analysis. Real-time processing capability was verified by the video data of two real scenarios. Synthetic data were tested to show the improvement in tracking performance by using the proposed detection framework.

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., Nanik, Mareyke M.W. Taira, and Wiwin Hendriani. "“She is a Spinster”: a Descriptive Study on Perception Toward Single Women." International Journal of Engineering & Technology 7, no. 2.29 (May 22, 2018): 667. http://dx.doi.org/10.14419/ijet.v7i2.29.13995.

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The aim of this research was to explore perception toward single women, according to respondents from 4 different subject groups. Exploration on topic was intriguing to be further researched, considering that the percentage of single women had been increasing in numerous countries, but the discussion was lacking, especially in Indonesia. Respondents in this study were Indonesian single or married men and women aged 25-70 years. Respondents were gathered through purposive incidental sampling (N = 128) and consisted of 41 single women, 49 married women, 13 single men, and 25 married men. An open-ended questionnaires constructed by the first author was used as measurement tools. Respondents were tasked to mention perceived positive and negative impression toward single women. Data gathered underwent two analysis stages. The first part was a descriptive content analysis and the second stage was a descriptive statistical analysis comparing means from one-way ANOVA. Statistical analysis showed significant result (average p < .05) when comparing means of positive and negative perception based on demographic statistics. Results showed significant negative perception and strong labeling toward single women although there were also significant positive perceptions. Negative and positive perceptions of single women tend to be universal from several generations of adults.

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41

Han, Jun, and Wei Dong Wang. "The Design of CIFF Structure Three-Order Switched-Capacitor Sigma-Delta Modulator." Advanced Materials Research 433-440 (January 2012): 5727–32. http://dx.doi.org/10.4028/www.scientific.net/amr.433-440.5727.

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This paper presents the design and implementation of a single-loop three-order switched-capacitor sigma-delta modulator(SDM) with a standard 0.18um CMOS technology. A current optimization technique is utilized in proposed design to reduce the power of operational transconductance amplifier(OTA).Using a chain of Integrators with weighted feed-forward summation(CIFF) structure and optimized single-stage class-A OTA with positive feed-back to minimize the power consumption. The SDM has been presented with an over-sampling ratio of 128,clock frequency 6.144MHz,24kHz band- width, and achieves a peak SNR of 100dB,103dB dynamic range. The whole circuits consume 2.87mW from a single 1.8V supply voltage.

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Danzer, Moritz Fabian, Jannik Feld, Andreas Faldum, and Rene Schmidt. "Reference curve sampling variability in one–sample log–rank tests." PLOS ONE 17, no. 7 (July 21, 2022): e0271094. http://dx.doi.org/10.1371/journal.pone.0271094.

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The one–sample log–rank test is the method of choice for single–arm Phase II trials with time–to–event endpoint. It allows to compare the survival of patients to a reference survival curve that typically represents the expected survival under standard of care. The one–sample log–rank test, however, assumes that the reference survival curve is known. This ignores that the reference curve is commonly estimated from historic data and thus prone to sampling error. Ignoring sampling variability of the reference curve results in type I error rate inflation. We study this inflation in type I error rate analytically and by simulation. Moreover we derive the actual distribution of the one–sample log–rank test statistic, when the sampling variability of the reference curve is taken into account. In particular, we provide a consistent estimate of the factor by which the true variance of the one-sample log–rank statistic is underestimated when reference curve sampling variability is ignored. Our results are further substantiated by a case study using a real world data example in which we demonstrate how to estimate the error rate inflation in the planning stage of a trial.

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Ma, Xianlin, Mishal Al-Harbi, Akhil Datta-Gupta, and Yalchin Efendiev. "An Efficient Two-Stage Sampling Method for Uncertainty Quantification in History Matching Geological Models." SPE Journal 13, no. 01 (March 1, 2008): 77–87. http://dx.doi.org/10.2118/102476-pa.

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Summary The paper presents a novel method for rapid quantification of uncertainty in history matching reservoir models using a two-stage Markov Chain Monte Carlo (MCMC) method. Our approach is based on a combination of fast linearized approximation to the dynamic data and the MCMC algorithm. In the first stage, we use streamline-derived sensitivities to obtain an analytical approximation in a small neighborhood of the previously computed dynamic data. The sensitivities can be conveniently obtained using either a finite-difference or streamline simulator. The approximation of the dynamic data is then used to modify the instrumental proposal distribution during MCMC. In the second stage, those proposals that pass the first stage are assessed by running full flow simulations to assure rigorousness in sampling. The uncertainty analysis is carried out by analyzing multiple models sampled from the posterior distribution in the Bayesian formulation for history matching. We demonstrate that the two-stage approach increases the acceptance rate, and significantly reduces the computational cost compared to conventional MCMC sampling without sacrificing accuracy. Finally, both 2D synthetic and 3D field examples demonstrate the power and utility of the two-stage MCMC method for history matching and uncertainty analysis. Introduction Uncertainty exists inherently in dynamic reservoir modeling because of several factors, the primary ones being the modeling error, data noise, and the nonuniqueness of the inverse problems that causes several models to fit the dynamic data. Under a Bayesian framework, the uncertainty in the reservoir models can be evaluated by a posterior probability distribution, which is proportional to the product of a likelihood function and a prior probability distribution of the reservoir model. To quantify the uncertainty, it is necessary to generate a sequence of model realizations that are sampled appropriately from the posterior distribution. Rigorous sampling methods, such as Markov Chain Monte Carlo (MCMC) (Oliver et al. 1997; Robert and Casella 1999), provide the accurate sampling albeit at a high cost because of their high rejection rates and the need to run a full flow simulation for every proposed candidate. There is also additional cost associated with a burn-in time needed for the MCMC to assure that the starting state does not bias sampling. Approximate sampling methods, such as randomized maximum likelihood (RML) (Oliver et al. 1996; Kitanidis 1995), are commonly used to avoid the high cost associated with the MCMC methods. For linear problems (Gaussian posterior distributions), RML has an acceptance probability of unity; however, the assumptions made in RML may be too restrictive for nonlinear problems, which is typically the case for reservoir history matching. The main appeal of RML is its computational efficiency and ease of implementation within the framework of traditional automatic history matching via minimization. There are also some examples in the literature that the RML has favorable sampling properties for nonlinear problems (Liu et al. 2001), although it is likely to be problem-specific. There is a need for an efficient and rigorous approach to uncertainty quantification for general nonlinear problems related to history matching. We propose a two-stage MCMC approach for quantifying uncertainty in history matching geological models. Our proposed sampling approach is computationally efficient with a significantly higher acceptance rate compared to traditional MCMC algorithms. In the first stage, we compute the acceptance probability for a proposed change in reservoir parameters based on a fast linearized approximation to flow simulation in a small neighborhood of the previously computed dynamic data. In this stage, no reservoir simulations are needed to explore the model parameter space. In the second stage, those proposals that passed a selected criterion of the first stage are assessed by running full flow simulations to assure the rigorousness in sampling. Then, these samples are either rejected or accepted using the MCMC selection criterion. It can be shown that the modified Markov chain converges to a stationary state corresponding to the posterior distribution. Moreover, the two-stage approach increases the acceptance rate, and reduces the computational cost required for the MCMC sampling. To propose MCMC samples, we consider two instrumental probability distributions, the random walk sampler and the Langevin sampler (Robert and Casella 1999). Both 2D synthetic and 3D field examples demonstrate that the two-stage MCMC method is computationally more efficient than the conventional MCMC methods, but does not sacrifice their accuracy. The proposed method has been successfully used in conjunction with single-phase upscaling methods (Efendiev et al. 2005). All examples in the paper are based on the fine-scale geological models.

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Yu, Alexander T., Rajani Shakya, Bikram Adhikari, Dipesh Tamrakar, Krista Vaidya, Stace Maples, Kashmira Date, et al. "A Cluster-based, Spatial-sampling Method for Assessing Household Healthcare Utilization Patterns in Resource-limited Settings." Clinical Infectious Diseases 71, Supplement_3 (November 1, 2020): S239—S247. http://dx.doi.org/10.1093/cid/ciaa1310.

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Abstract Background Implementation of population-based surveys is resource intensive and logistically demanding, especially in areas with rapidly changing demographics and incomplete or no enumeration of the underlying population and their residences. To remove the need for pre-enumeration and to simplify field logistics for the population healthcare utilization survey used for the Surveillance for Enteric Fever in Asia Project in Nepal, we incorporated a geographic information system–based geosurvey and field mapping system into a single-stage cluster sampling approach. Methods A survey was administered to ascertain healthcare-seeking behavior in individuals with recent suspected enteric fever. Catchment areas were based on residential addresses of enteric fever patients using study facilities; clusters were randomly selected from digitally created grids using available satellite images and all households within clusters were offered enrollment. A tablet-compatible geosurvey and mapping system that allowed for data-syncing and use in areas without cellular data was created using the ArcGIS suite of software. Results Between January 2017 and November 2018, we surveyed 25 521 households in Nepal (16 769 in urban Kathmandu and 8752 in periurban Kavrepalanchok), representing 84 202 individuals. Overall, the survey participation rate was 90.9%, with geographic heterogeneity in participation rates within each catchment area. Areas with higher average household wealth had lower participation rates. Conclusion A geographic information system–based geosurvey and field mapping system allowed creation of a virtual household map at the same time as survey administration, enabling a single-stage cluster sampling method to assess healthcare utilization in Nepal for the Surveillance for Enteric Fever in Asia Project . This system removed the need for pre-enumeration of households in sampling areas, simplified logistics and could be replicated in future community surveys.

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Bahder, Brian W., Noemi Soto, De-Fen Mou, Alessandra R. Humphries, and Ericka E. Helmick. "Quantification and Distribution of the 16SrIV-D Phytoplasma in the Wild Date Palm, Phoenix sylvestris, at Different Stages of Decline Using Quantitative PCR (qPCR) Analysis." Plant Disease 104, no. 5 (May 2020): 1328–34. http://dx.doi.org/10.1094/pdis-10-19-2146-re.

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Lethal bronzing disease (LBD) is a fatal infection in a variety of ornamental palms in Florida caused by the 16SrIV-D phytoplasma. The disease was first found in 2006 in Florida and has since spread to 31 different counties, reaching as far north as Jacksonville and as far south as Key Largo. Stakeholders (nursery personnel, landscaping personnel, and extension agents) from across the state take and send samples for analysis. To provide better sampling recommendations and reduce the time associated with the sampling process, the distribution of the 16SrIV-D phytoplasma was examined by quantitative PCR analysis in various Phoenix sylvestris that displayed different stages of decline, including early symptoms, moderate symptoms, and late symptoms. A declining Sabal palmetto was also available for analysis and examined as well. The findings of this study revealed that regardless of the stage of decline, the highest amount of phytoplasma detected was nearest to the base of the trunk and gradually decreased further up the trunk. Also, in P. sylvestris it was found that with symptoms present, the entire trunk has a systemic infection, resulting in positive reactions for every sample taken. These data are useful to stakeholders because they provide useful sampling recommendations in that only a single sample is needed when sampling a palm suspected to be infected with phytoplasma. Also, based on these results, sampling lower on the trunk is advised.

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El Aroudi, Abdelali, Reham Haroun, Mohamed Al-Numay, and Meng Huang. "Multiple-Loop Control Design for a Single-Stage PV-Fed Grid-Tied Differential Boost Inverter." Applied Sciences 10, no. 14 (July 13, 2020): 4808. http://dx.doi.org/10.3390/app10144808.

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This paper focuses on the control design of a differential boost inverter when used in single-stage grid-tied PV systems. The inverter performs both Maximum Power Point Tracking (MPPT) at the DC side and Power Factor Correction at the AC side. At first, the state-space time-domain averaged model of the inverter is derived and the small signal frequency domain model is obtained using a quasi-static approximation in which the inverter is treated as a DC–DC converter with a slowly varying output voltage. Then, the controllers are designed using a three-loop strategy in which the inverter inductor currents loop is used for suitable compensation, the DC Photovoltaic (PV) voltage loop is used for MPPT and the output grid current loop is used for Power Factor Correction (PFC) and active power control. The selection of the control parameters is based on a compromise among suitable system performances such as settling time of the input PV voltage, the sampling period of the MPPT, total harmonic distortion of the output grid current, power factor as well as suppression of subharmonic oscillation for all the range of the operating duty cycle. The resulting design ensures that the oscillations of the voltage, current and power at the DC side and the grid current at the AC side are effectively controlled. The validity of the proposed control design is verified by numerical simulations performed on the switched model of the system demonstrating its robustness and fast response under irradiance variations and MPPT perturbations despite the nonlinearity and complexity of the system.

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Levy, Paul S., Elena S. H. Yu, William T. Liu, Siu-Chi Wong, Ming-Yuan Zhang, Zheng-Yu Wang, and Robert Katzman. "Single-stage cluster sampling with a telescopic respondent rule: A variation motivated by a survey of dementia in elderly residents of Shanghai." Statistics in Medicine 8, no. 12 (December 1989): 1537–44. http://dx.doi.org/10.1002/sim.4780081214.

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48

Smith, D. R., J. T. Rogala, B. R. Gray, S. J. Zigler, and T. J. Newton. "Evaluation of single and two-stage adaptive sampling designs for estimation of density and abundance of freshwater mussels in a large river." River Research and Applications 27, no. 1 (January 2011): 122–33. http://dx.doi.org/10.1002/rra.1334.

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Zhang, Hai Bin, Si Liang Lu, Shang Bin Zhang, Ke Sai Ouyang, and Fan Rang Kong. "A New Cascaded Stochastic Resonance System and its Application to Weak Double-Frequency Signal Separation." Applied Mechanics and Materials 511-512 (February 2014): 346–51. http://dx.doi.org/10.4028/www.scientific.net/amm.511-512.346.

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Weak signal detection has attracted many researchers attention all over the world. Most of the methods focus on the single frequency signal. This paper introduces a new method to separate the weak double-frequency signal overwhelmed in heavy background noise. The cascaded stochastic resonance (SR) system (CSRS) is composed of a bistable SR model in the first stage and a tristable one in the second. Based on the characteristic of the SR system, we can amplify the useful signal of high frequency using twice sampling technic to make its parameters matching the requirements of the system. In our proposed cascade stochastic resonance system, we highlight the appointed frequency from high to low successfully with adjusting the twice sampling multiple and the high pass filter band. The signal composition of different frequency can be obtained from the systems two stage output. Simulated experiment validates the CSRSs availability in weak double-frequency signal separation and also its promising application in a more complex mixed signal.

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Miller, David L., David Fifield, Ewan Wakefield, and Douglas B. Sigourney. "Extending density surface models to include multiple and double-observer survey data." PeerJ 9 (September 2, 2021): e12113. http://dx.doi.org/10.7717/peerj.12113.

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Spatial models of density and abundance are widely used in both ecological research (e.g., to study habitat use) and wildlife management (e.g., for population monitoring and environmental impact assessment). Increasingly, modellers are tasked with integrating data from multiple sources, collected via different observation processes. Distance sampling is an efficient and widely used survey and analysis technique. Within this framework, observation processes are modelled via detection functions. We seek to take multiple data sources and fit them in a single spatial model. Density surface models (DSMs) are a two-stage approach: first accounting for detectability via distance sampling methods, then modelling distribution via a generalized additive model. However, current software and theory does not address the issue of multiple data sources. We extend the DSM approach to accommodate data from multiple surveys, collected via conventional distance sampling, double-observer distance sampling (used to account for incomplete detection at zero distance) and strip transects. Variance propagation ensures that uncertainty is correctly accounted for in final estimates of abundance. Methods described here are implemented in the dsm R package. We briefly analyse two datasets to illustrate these new developments. Our new methodology enables data from multiple distance sampling surveys of different types to be treated in a single spatial model, enabling more robust abundance estimation, potentially over wider geographical or temporal domains.

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Статті в журналах з теми "Single Stage Sampling"

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