scholarly journals A theory of average response to large jump perturbations

2019 ◽  
Vol 29 (8) ◽  
pp. 083128 ◽  
Author(s):  
Rafail V. Abramov
Keyword(s):  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ahmad H. Bokhari ◽  
Martin Berggren ◽  
Daniel Noreland ◽  
Eddie Wadbro

AbstractA subwoofer generates the lowest frequency range in loudspeaker systems. Subwoofers are used in audio systems for live concerts, movie theatres, home theatres, gaming consoles, cars, etc. During the last decades, numerical simulations have emerged as a cost- and time-efficient complement to traditional experiments in the design process of different products. The aim of this study is to reduce the computational time of simulating the average response for a given subwoofer design. To this end, we propose a hybrid 2D–3D model that reduces the computational time significantly compared to a full 3D model. The hybrid model describes the interaction between different subwoofer components as interacting modules whose acoustic properties can partly be pre-computed. This allows us to efficiently compute the performance of different subwoofer design layouts. The results of the hybrid model are validated against both a lumped element model and a full 3D model over a frequency band of interest. The hybrid model is found to be both accurate and computationally efficient.


2005 ◽  
Vol 85 (1) ◽  
pp. 81-93 ◽  
Author(s):  
C. A. Campbell ◽  
R. P. Zentner ◽  
F. Selles ◽  
P. G. Jefferson ◽  
B. G. McConkey ◽  
...  

Assessment of the long-term impact of fertilizers and other management factors on crop production and environmental sustainability of cropping systems in the semi-arid Canadian prairies is needed. This paper discusses the long-term influence of N and P fertilizers on crop production, N uptake and water use of hard red spring wheat (Triticum aestivum L.), and the effect of the preceding crop type [flax (Linum usitatissimum L.) and fall rye (Secale cereale L.)] on wheat grown on a medium-textured, Orthic Brown Chernozem at Swift Current, Saskatchewan. We analysed 36 yr of results (1967–2002) from eight crop rotation-fertility treatments: viz., fallow-wheat receiving N and P (F-W, N + P), three F-W-W treatments fertilized with (i) N + P, (ii) P only, and (iii) N only; two other 3-yr mixed rotations with N + P (i) F-flax-W (F-Flx-W) and (ii) F-fall rye-W (F-Rye-W); and two continuous wheat rotations (Cont W), one receiving N + P and the other only P. Growing season weather conditions during the 36-yr period were near the long-term mean, but the first 22 yr were generally drier than normal while the last 14 yr (1989–2002) had average to above-average growing conditions. This was partly responsible for grain and N yield being greater in the latter period than in the first 22 yr. The 36-yr average response of wheat grown on fallow to P fertilizer was 339 kg ha-1, while the response to N fertilizer over this period was only 123 kg ha-1. The 36-yr average response of wheat grown on stubble to N was 344 kg ha-1 for F-W-(W) and 393 kg ha-1 for Cont W. Neither flax nor fall rye influenced the yield response of the following wheat crops. Annualized grain production for F-W (N + P), F-W-W (+ N) and F-W-W (+ P) rotations were similar (1130 kg ha-1 yr-1); this was about 15% lower than for F-W-W (N + P), 40% lower than for Cont W (N + P), and 5% lower than for Cont W (+ P). Annualized aboveground N yield for Cont W (N + P) was 57% higher than for Cont W (+ P). Regressions were developed relating straw to grain yields for wheat, flax and fall rye. The amount of NO3-N left in the soil was directly related to amount of N applied and inversely to N removed in the crop. Thus, F-(W)-W (+ N) left about 28% more NO3-N in the rooting zone than F-(W)-W (N + P), while F-W-(W) (N + P) left 20% more than F-W-(W) (+ P), and Cont W (N + P) left 39% more than Cont W (+ P). F-Rye-W (N + P) left much less NO3-N in the soil than any other fallow-containing system and similar amounts to Cont W (N + P). Key words: Yields, grain protein, N and P fertilizer, straw/grain regressions, water use, soil nitrate


2018 ◽  
Vol 64 (3) ◽  
pp. 272-280 ◽  
Author(s):  
Nuno Basílio ◽  
Sara Cardoso ◽  
José Mendes Nunes ◽  
Liliana Laranjo ◽  
Maria da Luz Antunes ◽  
...  

Summary Introduction: Surveys are a useful tool in primary care. However, low response rates can introduce selection bias, impairing both external and internal validity. The aim of this study was to assess the average response rate in surveys with Portuguese general practitioners (GPs). Method: We searched the Medline, Web of Science, Scopus, Embase, PsychInfo, SciELO, IndexRMP, RCAAP, Revista Portuguesa de Medicina Geral e Familiar, Acta Médica Portuguesa and the proceedings of conferences of general practice from incepton to December 2016. We included all postal, e-mail, telephone and personal surveys to primary care physicians without language restrictions. We did not assess risk of bias of included studies, since the main outcome was survey response rate. We performed planned subgroup analyses of the use of monetary incentives, the use of non-monetary incentives, survey delivery modes and prior contact with participants. Results: A total of 1,094 papers were identified and 37 studies were included in this review. The response rate in surveys done to Portuguese GPs was 56% (95CI 47-64%). There was substantial heterogeneity among included studies (I2=99%), but subgroup analysis did not explain this heterogeneity. Conclusion: Consistent with other published studies, the average response rate in surveys done with Portuguese GPs was 56%, with substantial variation among studies. Use of monetary incentives, one of the most effective strategies to increase response rates, was not present in any of the included studies.


2020 ◽  
Vol 4 (1) ◽  
pp. 83
Author(s):  
Anike Putri ◽  
Yenita Roza ◽  
Maimunah Maimunah

This research was motivated by the still limited learning of mathematics as a means of supporting learning in the 2013 Curriculum. The purpose of this study was to produce some products in the form of learning devices (syllabus, RPP and LKPD) on the material for the flat side building of VIII Middle School with discovery learning models that meet valid, practical, and effective criteria for improving students mathematical critical thinking skills. Learning tools are developed using the 4-D model, which are define, design, develop and assess. The research instrument used was an instrument of validity in the form of a validation sheet to assess the feasibility of the syllabus, RPP and LKPD as well as a practical instrument in the form of a teacher observation sheet activity in applying the discovery learning model and student questionnaire responses to assess the practicality of LKPD. The results of the validation of the experts stated that the product developed reached a valid category with an average rating of 76.67% for syllabus, 76.67% for RPP and 88.04% for LKPD. Learning devices are considered very practical in small group trials with an average response of 96.44% students and large group trials from the observation sheet of teacher activity 93.71% and the average response of students 87.77%. The learning tools have been proved to improve students mathematical critical thinking skills in terms of an average N-gain of 0.53 in the medium category.


Author(s):  
Jolly Bhadra ◽  
Hemalatha Parangusan ◽  
Zubair Ahmad ◽  
Shoaib Mallick ◽  
Farid Touati ◽  
...  

PANI coated Cu-ZnS porous microsphere structures have been synthesized by hydrothermal method and in-situ polymerization process. The synthesized composite is characterized by different techniques in order to study the structural, morphological and surface absorption properties. The experimental observation demonstrates that the PANI/1%Cu-ZnS composite has better sensitivity, fast response and good stability as compared to pure PANI and other PANI/CuZnS compositions. Finally, PANI/1% Cu-ZnS composite has been found to be optimized for the humidity sensors due to its well-distributed roughness, porosity and hydrophilicity. The average response and recovery times of the PANI/1% Cu-ZnS are found to be 42 s and 24 s, respectively, which outperform recent results.


2016 ◽  
Vol 9 (2) ◽  
pp. 57
Author(s):  
María Cristina Vega ◽  
Enrique Navarro ◽  
José Espinoza ◽  
José Luis Guerrero ◽  
Gustavo A. Burciaga

Twenty S5 sweet corn lines containing the opaque-2 gene that increases Iysine  contents as well as the sugary-2 gene were evaluated. The lines were crossed with three testers: one unrelated inbred line, and two related synthetic varieties. Six commercial and three experimental hybrids were used during the trials. Test crosses were evaluated in two locations of Mexico during 1994 using a randomized complete block designo The experiment's goal was to compare lines' performance in combination with three testers, taking into account yield, soundness, uniformity, and corn quality. The average response of lines combined with testers was superior than that of commercial hybrids for traits such as flowering time and plant and ear height. Performance factors analyzed (ear length, grain color, uniformity, soundness, and number of marketable ears) in trial crosses were superior or equal in average to those in experimental hybrids, but this was not the case with sugar percentage. The best results were observed with the unrelated LD tester inbred line for agronomic traits and performance factors. This study made possible the selection of lines for future breeding based on the above mentioned traits, as well as the general combining ability for ear length and number of green flag leaves.


The industrial revolution 4.0 demands the convenience of a human life facility. Not to forget also in the cleaning service. When we will dispose of trash, we do not need to look for the trash can, it is precisely the trash can that will approach us. This smartphone-based application uses the A * (A star) algorithm as the basis for its work, while for communication between smartphones with the trash can system using blue tooth. The smartphone sends its coordinate position through the Global Positioning System facility, then the trash can system will search for the sender's location. The experimental results show that the average stopping distance indoors without barrier is 7.03 meters with an average time response of 25.3 seconds, the average stopping distance in the room with a barrier of 7.2 meters with the average response time 3.6 seconds average, stopping distance outdoor without a barrier of 5.7 meters with an average response time of 258.3 seconds, and the average outdoor stopping distance with a barrier of 2.73 meters with a response an average time of 141.3 seconds.


2019 ◽  
Vol 6 (1) ◽  
pp. 32
Author(s):  
Pahriah Pahriah ◽  
Hendrawani Hendrawani

This development aims to determine the characteristics and feasibility of multipleinquiry-based representation modules in the reaction rate material through theADDIE stage (Analyze, Design, Development Implementation and Evaluation)developed by Thiagarajan. This research and development was carried out untilthe development stage with adjustments based on development needs. Theassessment instrument used to determine the feasibility of the module is aquestionnaire sheet. The module feasibility was assessed by 2 material experts, 1media expert, 1 linguist, 1 colleague, 1 practitioner, and 10 students as subjects.Students involved in this study came from chemistry education study programsthat had undergone basic chemistry courses through limited trials. The data onthe value of the grievances obtained are still in the form of qualitative data andthen processed into quantitative data. Quantitative data are analyzed for eachaspect of the assessment. The final score obtained is converted to the level ofproduct feasibility qualitatively with the guidelines according to the criteria ofthe assessment category. The results of expert validation showed the averagepercentage (a) of material experts was 84% with very feasible categories; (b)media experts 90% with very decent categories; (c) linguists 97% with verydecent categories; (d) colleagues 79.6 categories worth%; (e) practitioners86.4% are very decent categories. The average response of students to productdevelopment results 89.5% with a very feasible category. This shows that themodules developed are feasible to be used at the stage of large-scale trials.


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