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sequential good lattice point sets for computer experiments

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science China Mathematics 2024年第9期67卷 2153-2170页

作者： Xue-Ru Zhang Yong-Dao Zhou Min-Qian Liu dennis K.J.Lin NITFID LPMC&KLMDASRSchool of Statistics and Data ScienceNankai UniversityTianjin 300071China Department of statistics Purdue UniversityWest LafayetteIN 47907USA

sequential Latin hypercube designs(sLHDs) have recently received great attention for computer experiments, with much of the research restricted to invariant spaces. The related systematic construction methods are inflexible, and algorithmic methods are ineffective for large designs. For designs in contracting spaces, systematic construction methods have not been investigated yet. This paper proposes a new method for constructing sLHDs via good lattice point sets in various experimental spaces. These designs are called sequential good lattice point(sGLP) sets. Moreover, we provide efficient approaches for identifying the(nearly)optimal sGLP sets under a given criterion. Combining the linear level permutation technique, we obtain a class of asymptotically optimal sLHDs in invariant spaces, where the L1-distance in each stage is either optimal or asymptotically optimal. Numerical results demonstrate that the sGLP set has a better space-filling property than the existing sLHDs in invariant spaces. It is also shown that sGLP sets have less computational complexity and more adaptability.

关键词： contracting space maximin distance nested Latin hypercube design sequential design space-fillingdesign

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Asymptotic false discovery control of the Benjamini-Hochberg procedure for pairwise comparisons

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science China Mathematics 2024年

作者： Weidong Liu dennis Leung Qiman shao school of Mathematical sciences Shanghai Jiao Tong University school of Mathematics and statistics University of Melbourne Department of statistics and Data science SICM Southern University of Science and Technology

In a one-way analysis-of-variance(ANOVA) model, the number of pairwise comparisons can become large even with a moderate number of groups. Motivated by this, we consider a regime with a growing number of groups and prove that, when testing pairwise comparisons, the Benjamini-Hochberg(BH) procedure can asymptotically control false discoveries, despite the fact that the involved t-statistics do not exhibit the wellknown positive dependence structure required for exact false discovery rate(FDR) control. Following Tukey's perspective that the difference between the means of any two groups cannot be exactly zero, our main result provides control over the directional false discovery rate and directional false discovery proportion. A key technical contribution of our work is demonstrating that the dependence among the t-statistics is sufficiently weak to establish the convergence result typically required for asymptotic FDR control. Our analysis does not rely on conventional assumptions such as normality, variance homogeneity, or a balanced design, thereby offering a theoretical foundation for applications in more general settings.

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Evaluation of a Wireless solar Powered Personal Weather station

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Agricultural sciences 2024年第1期15卷 36-53页

作者： Robert J. Lascano Timothy s. Goebel dennis C. Gitz III John E. stout Cropping systems Research Laboratory Wind Erosion and Water Conservation Research Unit USDA-ARS Lubbock TX USA

We are evaluating dryland cotton production in Martin County, Texas, measuring cotton lint yield per unit of rainfall. Our goal is to collect rainfall data per 250 - 400 ha. Upon selection of a rainfall gauge, we realized that the cost of using, for example, a tipping bucket-type rain gauge would be too expensive and thus searched for an alternative method. We selected an all-in-one commercially available weather station;hereafter, referred to as a Personal Weather station (PWs) that is both wireless and solar powered. Our objective was to evaluate average measurements of rainfall obtained with the PWs and to compare these to measurements obtained with an automatic weather station (AWs). For this purpose, we installed four PWs deployed within 20 m of the Plant stress and Water Conservation Meteorological Tower that was used as our AWs, located at UsDA-ARs Cropping systems Research Laboratory, Lubbock, TX. In addition, we measured and compared hourly average values of short-wave irradiance (Rsub>gsub>), air temperature (Tsub>airsub>) and relative humidity (RH), and wind speed (Ws), and calculated values of dewpoint temperature (Tsub>dewsub>). This comparison was done over a 242-day period (1 October 2022-31 May 2023) and results indicated that there was no statistical difference in measurements of rainfall between the PWs and AWs. Hourly average values of Rsub>gsub> measured with the PWs and AWs agreed on clear days, but PWs measurements were higher on cloudy days. There was no statistical difference between PWs and AWs hourly average measurements of Tsub>airsub>, RH, and calculated Tsub>dewsub>. Hourly average measurements of Rsub>gsub> and Ws were more variable. We concluded that the PWs we selected will provide adequate values of rainfall and other weather variables to meet our goal of evaluating dryland cotton lint yield per unit rainfall.

关键词： Automation sensors Citizen Weather station Mesonet Rainfall Weather Variables

National social Investment Programmes in Nigeria:A Descriptive Analysis of the socio-Economic Contributions of N-Power Programme in Benue state

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Management studies 2024年第1期12卷 9-20页

作者： Robert Idoko Ogwola dennis Anyebe Olofu Charles Amobi Aneke Federal University GashuaNigeria National Council for Arts and Culture Garki-AbujaNigeria

This study analysed the socio-economic contributions of N-Power programme amongst the beneficiaries of the scheme in Benue *** to the introduction of N-Power programme,successive administrations in Nigeria have made concerted efforts towards improving the standard of living of the citizenry through the execution of various welfare or social intervention programmes,but not much successes were *** from the mistakes of the past regimes,and by way of deliberate state policy,the Buhari’s government initiated a multi-pronged social investment policy,one of which is the N-power programme that came onboard in 2016,which also doubles as the subject of this *** achieve the goal of this study,a combination of desktop research and survey design was *** were administered to 390 respondents through a combination of stratified and random sampling *** results of the survey were matched with that of the secondary data obtained through online websites and other related *** result indicated that N-Power made positive contributions to the socio-economic life of the beneficiaries in Benue state:specifically,the scheme contributed in poverty eradication,employment generation,skills acquisitions and capacity ***,some aspect of our findings revealed that the programme has a number of challenges such as:inadequate cash support,delay in monthly cash transfer to beneficiaries,distance participants had to move to their work stations,absence of posting in N-Teach scheme,and lack of adequate working tools amongst *** salvage this problem the paper recommended the following solutions:expansion of the scheme to cover N-Teach and other aspects,increment in the monthly cash transfer to cushion the high rate of inflation,support for the participants/beneficiaries in transportation and logistics,enrolment of more youth into the various schemes,proper monitoring and evaluation of the implementation of the schemes among

关键词： national social investment programme N-Power contributions socio-economic development

Application of the shrinking Particle Model for the Evaluation of Molecular Recyclability of PET versus semi-Aromatic Polyesters

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Open Journal of Physical Chemistry 2024年第2期14卷 21-35页

作者： Jack van schijndel sanne de Krom dennis Molendijk Koen van Beurden Amarante Böttger Research Group Biopolymers/Green Chemistry Centre of Expertise Safe & Resilient Society Avans University of Applied Science Breda Netherlands New Materials and Their Applications Centre of Expertise Safe & Resilient Society Avans University of Applied Science Breda Netherlands Department of Materials science and Engineering Delft University of Technology Delft Netherlands

The molecular recyclability of poly (ethylene terephthalate) (PET) and three semi-aromatic polyesters poly (phloretic acid) (poly-H), poly (dihydroferulic acid) (poly-G), and poly (dihydrosinapinic acid) (poly-s) is evaluated in this study. PET is an extensively used aromatic polyester, and poly-H, poly-G, and poly-s can be considered semi-aromatic poly (lactic acid) modifications. All these polyesters have been depolymerized at neutral pH and by acid- and base-catalyzed hydrolysis at two temperatures, i.e., 50˚C and 80˚C. Base-catalyzed depolymerization of virgin PET leads to an isolated yield of 38% after 48 hours of reaction at 80˚C. Contrary to these results for PET, almost all the monomers of the semi-aromatic polyesters poly-H, poly-G, and poly-s are recovered with isolated yields larger than 90% at the same temperature after 15 minutes in a facile manner. A shrinking particle model used to determine the global kinetics of the base-catalyzed depolymerization showed that the rate rises with increasing temperature. Using the shrinking particle model, the intrinsic reaction rate constants were determined. It has been demonstrated that the rate coefficients of the depolymerization of the semi-aromatic polyesters poly-H, poly-G, and poly-s are between 2 and 3 orders of magnitude higher than those for PET.

关键词： Depolymerization Molecular Recycling Poly-H Poly-G Poly-s PET Circular Polymers

Water, sanitation and Hygiene in Lower-Level Health Care Facilities of Dar es salaam Region in Tanzania: status towards Achieving the sustainable Development Goals and Way Forward

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Advances in Infectious Diseases 2024年第1期14卷 279-295页

作者： Mariam Mahamudu Hussein Mohamed Michael Habtu dennis Rweyemamu Anyitike Mwakitalima Amour seleman Erick Mgina Khalid Massa Grace saguti Andre Arsene Bita Fouda Zabulon Yoti Ministry of Health Dodoma Tanzania Department of Environmental and Occupational Health Muhimbili University of Health and Allied Sciences Dar es Salaam Tanzania Regional Office for Africa World Health Organization Brazzaville Republic of the Congo National Institute for Medical Research Dar es Salaam Tanzania

Background: Improving Water, sanitation and Hygiene in health care settings is a critical prerequisite for achieving national health goals and sustainable Development Goals (sDGs). The World Health Organization (WHO) has set a target for each United Nations member state to reach by 2030. Each member state is required to reach by 2022, 2025 and 2030 at least 60%, 80% and 100%, respectively of basic level of service of the five elements which are water, sanitation, hygiene, waste management and environmental cleaning. Methods: This study aimed to evaluate and document the current state of basic water, sanitation, and hygiene services in all lower-level health care facilities in the Dar es salaam region of Tanzania as of July 2022. A cross-sectional study was conducted in 99 public dispensaries in the Dar es salaam region’s five councils: Ubungo, Kigamboni, Kinondoni and Temeke Municipalities, and Ilala City. The interviewee form and observational checklists were both digitalized using the Kobo tool software. The respondents were health care facility in-charges or nurse in-charges. Data were downloaded, validated, and imported to stata version 15 for analysis. Results: The basic WAsH level per JMP is far below the target in 2022. Each member state by 2022 is required to reach at least 60% of the basic level of service of each element. We found a low coverage of basic WAsH in the 99 dispensaries included in this study. The basic WAsH coverage was met in only 10 (10.1%) of the dispensaries, while the remaining 89 (89.9%) dispensaries fall on limited WAsH services. Conclusion: This study revealed lower coverage of basic WAsH services in dispensaries. An urgent need is required to improve the status of WAsH in all the dispensaries and facilitate the provision of quality health care services, patient safety and reduce health care associated infections.

关键词： Dispensaries Low Level Health Care Facilities service Levels Basic WAsH Dar es salaam

Principles to support Modular software Construction

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Journal of Computer science & Technology 2017年第1期32卷 3-10页

作者： Jack B. dennis Department of Electrical Engineering and Computer science Massachusetts Institute of Technology Cambridge MA 02139 U.S.A.

The construction of large software systems is always achieved through assembly of independently written components -- program modules. For these software components to work together, they must share a common set of data types and principles for representing structured data such as arrays of values and files. This common set of tools for creating and operating on data objects is provided by the infrastructure of the computer system： the hardware, operating system and runtime code. Because the nature and properties of these tools are crucial for correct operation of software components and their inter-operation, it is essential to have a precise specification that may be used for verifying correctness of application software on one hand, and to verify correctness of system behavior on the other. We call such a specification a program execution model （PXM）. It is evident that the properties of the PXM implemented by a computer system can have serious impact on the ability of application programmers to practice modular software construction. This paper discusses the concept of program execution models and presents a set of principles that a PXM must satisfy to provide a sound basis for modular software construction. Because parallel program execution on computer systems with many processing units is an essential part of contemporary computing environments, the expression of parallelism and modular software construction using components involving parallel operations is included in this treatment. The conclusion is that it is possible to build computer systems that implement a PXM within which any parallel program may be used, unmodified, as a component for building more substantial parallel programs.

关键词： program execution model data flow model codelet abstract architecture parallel computing

Review of current method to determine outburst threshold limits in Australian underground coal mines

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International Journal of Mining science and Technology 2019年第6期29卷 859-865页

作者： dennis J.Black CoalGAs Department of Civil Mining and Environmental Engineering University of Wollongong

Desorption rate index(DRI)was presented to the Australian underground coal industry in 1995 as a means for determining outburst threshold limits for Australian coal *** is a measure of the gas volume released from a coal sample in the first 30 s of crushing during the Q3 stage of gas content testing,multiplied by the ratio between measured Q3 and *** were identified between QM and DRI for both CO2 and CH4 rich coal samples collected from the Bulli seam at West Cliff Colliery and that identified relationship was referred to as the Bulli seam *** outburst mining gas content threshold limit values specified for the Bulli seam at that time,when applied to the QM-DRI Bulli seam benchmark,was shown to closely align with a DRI value of 900(DRI900),for both CO2 and CH4 rich seam gas *** Australian coal industry adopted the DRI900 as the basis for determining outburst gas content TLV for Australian coal *** mining experience in Australia has shown that gas content is not the only significant factor that impacts outburst risk,as all significant outburst events have been associated with abnormal geological conditions,such as faults and ***,assessing the potential application of additional outburst risk factors,to accurately define outburst risk zones,set safe mining threshold levels,and determine appropriate mining controls,warrants further *** Australian coal mines have implemented mining procedures enabling mining to continue in areas with gas content greater than the TLV determined using the DRI900 approach,without inducing an *** is a broad lack of understanding among Australian coal mine operators as to the procedure and calculations used to determine ***,there has been growing concern regarding the accuracy and validity of the DRI900 method for determining outburst TLV.A comprehensive set of gas data has been collected from Australian coal seams,including the Bulli seam,and t

关键词： Outburst Desorption rate DRI Threshold limit

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Ethene／norbornene copolymerization by[Me2si（3—^tertBuCp）（N^tertBu）]TiCl2／MAO—catalyst

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Journal of Zhejiang University science 2003年第2期4卷 121-130页

作者： TRANPhu-dennis KAMINsKYWalter InstituteofTechnicalandMacromolecularChemistry UniversityofHamburgGermany

?Ethene/norbornene copolymerization by the catalyst system [Me_2si( 3- tertBuCp)(N tertBu)]TiCl_2/MAO was investigated in detail at 30 ℃, 60℃, and 90℃. A mass flow controller was used in this work to obtain kine tic data and investigate tempera ture's effects on activity, norbornene incorporation, copolymerization parameter , microstructure, glass transition temperature, and molar masses were described. H igh copolymerization values r_E and high alternation are determined. The n umber of isotactic alternating sequences is much higher than that of the syndiot actic alter nating sequences.

关键词： Polymerization Ethene/norbornene copolymers Const rained geometry catalyst Temperature effects.