PM Methods Research Articles

A Review of the State of Art of Fabrication Technologies of Titanium Aluminide (Ti-Al) Based on US Patents

This article evaluates the fabrication technologies of titanium aluminide (Ti-Al) and its practical applications by comparing it with the well-known Ti-Al binary phase diagram and US patents. Meanwhile, by analyzing and discussing the various patented Ti-Al fabrication technologies and applications, this article discusses the applications of Ti-Al-based alloys, mainly in the aircraft field. The improved fabrication processes and new application technologies are under patent protection. These technologies are classified into six categories: basic research on Ti-Al-based alloys, powder metallurgy of Ti-Al-based alloys, casting and melting of Ti-Al-based alloys, PM and AM manufacturing methods for aircraft applications, other fabrication technologies by Ti-Al-based alloys, and self-propagating high-temperature synthesis (SHS) of Ti-Al-based alloys. By comparing the principles and characteristics of the above techniques, the advantages, disadvantages, and application fields of each are analyzed and their developments are discussed. Based on the characteristics of Ti-Al, new fabrication and application technologies can be developed, which can overcome the existing disadvantages and be used to form new aircraft components.

Assessment of OXIS contacts-a comparison of three methods.

To compare OXIS contacts by means of Replication using Sectional die Models (RSM) and Photographs of the Models (PM) with Direct Clinical Examination (DCE) in a sample of preschool children aged 3-4years. A retrospective cross-sectional study was performed using existing records of sectional die models and their photographs among 4257 contacts of 1104 caries-free pre-school children. Two calibrated examiners scored the contacts between the distal surface of the primary first molar and mesial surface of the primary second molar using OXIS criteria from the occlusal view using the RSM & PM methods. These were compared to the OXIS scores from DCE method which was available from previous records. Kappa agreement was used to compare results obtained RSM and PM methods with DCE. The kappa agreement between the RSM and DCE methods was 98.48%; and between the PM and DCE methods was 99.42%, both of which indicated perfect agreement. The RSM and PM methods were found to have an excellent agreement in scoring OXIS contacts when compared to the DCE method. PM was found to be slightly more accurate than the RSM method for scoring OXIS contacts.

GPM: A graph convolutional network based reinforcement learning framework for portfolio management

Portfolio management is a decision-making process of periodically reallocating a certain amount of funds into a portfolio of assets, with the objective of maximizing the profits constrained to a given risk level. Due to its nature of learning from dynamic interactions and planning for long-run performance, reinforcement learning (RL) recently has received much attention in portfolio management. However, most of existing RL-based PM approaches in general only consider price changes of portfolio assets and the implicit correlations between price changes, while ignoring the rich relations between companies in the market, such as two assets in the same sector or two companies have a supplier-customer relation, which are very important for trading decision making. To address these limitations, in this paper, we propose GPM, a novel graph convolutional network-based reinforcement learning framework for portfolio management, which first employs Relational Graph Convolutional Network (R-GCN) to extract asset relational features, and then combines relational features with multi-scale temporal features to make trading decisions for better performance. We also introduce softmax with temperature to increase portfolio diversity, which leads to further increase in profits. Experimental results on two real-world datasets: NASDAQ and NYSE, validate the effectiveness of GPM over state-of-the-art PM methods. Further, more experiments are conducted to evaluate GPM with different graph neural networks and different number of network layers, to explore proper settings for different markets.

Estimating Rainfall Interception of Pinus hartwegii and Abies religiosa Using Analytical Models and Point Cloud

Rainfall interception plays a role in the hydrological cycle and is a critical component of water balances at the basin level, which is why understanding it is very important; as a result, in recent years, various authors have proposed different models to explain this process and identify which of them adapts better to each forest species. In this context, the aim of this research was to evaluate the Gash model and the sparse Gash analytical model in Pinus hartwegii Lindl. and Abies religiosa (Kunth) Schltdl. et. Cham., using measurements from 20 precipitation events recorded in May and June 2018 at the Zoquiapan Experimental Forest Station, Mexico. The evaporation rate was calculated using the Penman–Monteith method (PM) and Gash’s calculation procedure. The canopy parameters were also calculated with two methods, a graphical one (A) and a method proposed in this research (B), which is based on point cloud generated with drone photogrammetry. For P. hartwegii, the most accurate model to estimate interception per rainfall event was the Gash model with the A and Gash methods, which were used to calculate the canopy parameters and evaporation rates, respectively; for accumulated interception, the sparse Gash analytical model with the B and PM methods was used. For A. religiosa, the best fit for individual events was presented by the sparse Gash analytical model with the B and PM methods, and for accumulated interception, it was the Gash model with the B and Gash methods. The results allow concluding that the B method proposed in this research is a good alternative for the calculation of rainfall interception, since it tends to improve its estimation, shortening the time for acquiring information about the parameters of the canopy structure and thus minimizing the costs involved.

Comparison of balanced direct search and iterative angular spectrum approaches for designing acoustic holography structure

There are many pure phase methods for designing acoustical holography structures in the known literature. Different methods may have different characteristics and lead to different results, but few researchers put these methods together for comparison. So we have no idea which method should be taken when dealing with a specific optimization case. This paper investigated the characteristics of three different PM methods, one is the direct search method taking suitable objective function and another two are the conventional IASA methods but with different restricts in image plane, one called ISREL relaxes the whole background pressure constraints and one called ISRES restricts the whole background pressure to zero. We find that DS is a balanced method in terms of various metrics evaluating target pattern and background noise. Finally, the ability of particle manipulation of DS was verified experimentally by designing a holography structure projecting a circle with a non-uniform phase gradient. In a word, it provides a specific comparison between the two mainstream methods DS and IASA by two optimization cases. On one hand, it gives us a clear view of the characteristics of these methods in designing acoustic holography; On the other hand, we know that DS may be a preferred algoritm for most optimization cases owing to its balanced characteristic regardless of time costs.

Experimental comparison between performance of the PM and LPM methods in computed radiography

The scatter downgrades the image quality and reduces its information efficiency in quantitative measurement usages when creating projections with ionizing radiation. Therefore, the variety of methods have been applied for scatter reduction and correction of the undesirable effects. As new approaches, the ordinary and localized primary modulation methods have already been used individually through experiments and simulations in medical and industrial computed tomography, respectively. The aim of this study is the evaluation of capabilities and limitations of these methods in comparison with each other. For this mean, the ordinary primary modulation has been implemented in computed radiography for the first time and the potential of both methods has been assessed in thickness measurement as well as scatter to primary signal ratio determination. The comparison results, based on the experimental outputs which obtained using aluminum specimens and continuous X-ray spectra, are to the benefit of the localized primary modulation method because of improved accuracy and higher performance especially at the edges.

A new project management approach for R&D software projects in the automotive industry - continuous V-model

Most current work activities in R&D centres are innovative and dynamic, with project management acting as the discipline that governs them. The improvement of PM methods has become a necessity due to the following main factors: classical methodologies are increasingly difficult to apply, cutbacks in project duration are requested by organisations and customers, demands for product quality are continuously expanding. The paper examines how PM concepts are used in developed R&D projects, based on the V-model approach. It also introduces an enhanced new approach called Continuous V-model - CVM, based on agile concepts. The model has been applied on a real automotive R&D project and the resulted KPIs have been benchmarked to the standard approach on a similar project. The main result of this research is an incremental PM concept that may easily include changes requested by the customer, reducing development time and number of errors in the final delivered package.

COMPARISON OF METHODS FOR ESTIMATING REFERENCE EVAPOTRANSPIRATION: AN APPROACH TO THE MANAGEMENT OF WATER RESOURCES WITHIN AN EXPERIMENTAL BASIN IN THE BRAZILIAN CERRADO

ABSTRACT: This study aimed to compare methods for estimating reference evapotranspiration using an experimental basin in the Brazilian Cerrado, for water management purposes. For that, we estimated daily reference evapotranspiration over a certain period (time series between 1982 and 2012) through different empirical methods. These methods consisted of Blaney-Criddle (BC), Hargreaves & Samani (HS), ASCE Penman-Monteith (ASCE- PM), Penman (1948/1963) (PO), Priestley-Taylor (PT), which were all compared to the standard Penman-Monteith FAO-56 (PM-FAO56). Based on statistics, ASCE- PM, P and BC methods should be recommended for cerrado areas, either in rainy or dry seasons. After these, the PT also stood out. Among the less complex methods, based on temperature and energy data, PT method is recommended whether climatological data are scarce either in rainy or dry seasons. Yet, HS reached the greatest errors, a broad data spread and low estimate accuracy, but showing better performance in dry periods, thus remaining under restricted use.

VIS-NIR SPECTROMETRY, SOIL PHOSPHATE EXTRACTION METHODS AND INTERACTIONS OF SOIL ATTRIBUTES

The objective of this study was to evaluate the relationships between the spectra in the Vis-NIR range and the soil P concentrations obtained from the PM and Prem extraction methods as well as the effects of these relationships on the construction of models predicting P concentration in Oxisols. Soil samples' spectra and their PM and Prem extraction solutions were determined for the Vis-NIR region between 400 and 2500 nm. Mineralogy and/or organic matter content act as primary attributes allowing correlation of these soil phosphorus fractions with the spectra, mainly at wavelengths between 450-550, 900-1100 nm, near 1400 nm and between 2200-2300 nm. However, the regression models generated were not suitable for quantitative phosphate analysis. Solubilization of organic matter and reactions during the PM extraction process hindered correlations between the spectra and these P soil fractions. For Prem,, the presence of Ca in the extractant and preferential adsorption by gibbsite and iron oxides, particularly goethite, obscured correlations with the spectra.

Powder metallurgy on its way to nanocrystalline structures

Metallic and ceramic dense nanocrystalline (nc–)materials with average grain sizes of about 5 to 100 nm may be produced by means of powder technology at relatively low temperatures. This is achieved by using nano–dispersed, i.e. highly sinter–active starting powders. It is the extremely high grain–/phase–boundary area that determines the unusual properties of the resultant PM–components. The various suitable PM–methods for the production of pure as well as composite nc–materials are shortly reviewed including the sol–gel–process, mechanical alloying and the inert gas evaporation method. Some of the fascinating potentials of PM–fabricated nc–materials due to their peculiar magnetic, electronic and mechanical behaviour are elucidated.

Developing Competency-based, Industry-driven Manufacturing Education in the USA: Bringing together Industry, Government and Education Sectors

In recent years, the U.S. has been experiencing a shift in technical and professional education. Industry, education and government stakeholders are redefining their partnerships and working together to create competency-based, industry-driven education at the local, state, and national levels. These form the fundamental principles of a paradigm shift in education needed to combine and enhance innovative educational approaches from different research fields, as well as best-practice models from other countries. This paradigm shift presents a challenge, as education and public sectors are typically not familiar with matured (project) management principles, and often follow the “Garbage Can- Model”(Cohen, 1964), while, simultaneously, industry experts lack experience and knowledge about the academic and public world. But both have to answer questions like: How can PM measure progress in an educational project? Which PM methods are most/least helpful? Using a case study approach to the research, this paper will analyze several highly visible and innovative stakeholder partnerships that are breaking traditional curriculum and assessment models. Using industry subject matter experts, both the Michigan Advanced Technician Training (MAT2) program have developed a competency- based curriculum that incorporates a sophisticated methodology of assessments using the industry-driven DACUM approach as the foundation. The new model requires a sophisticated methodology for tracking learning analytics including performance, completion rates, and learning gaps. This paper will propose a solution.

Inclusion complex of (−)-linalool and β-cyclodextrin

(−)-Linalool is a monoterpene alcohol which is present in the essential oils of several aromatic plants. Recent studies suggest that (−)-linalool has antimicrobial, anti-inflammatory, anticancer, antioxidant, and antinociceptive properties in different animal models. The aim of this study was to prepare and characterize inclusion complexes of (−)-linalool with β-cyclodextrin (β-CD). Equimolar binary (−)-linalool/β-CD systems were prepared by physical mixture, paste (PM), and slurry methods (SC) and characterized by differential scanning calorimetry, thermogravimetric analysis, FT-IR spectroscopy, X-ray diffractometry, Karl Fisher titration, and scanning electron microscopy. Thermal characterization indicates the occurrence of complexation, mainly in paste complexes, which is present in the interval from 140 to 280 °C a gradual mass loss (4.6 %), probably related to (−)-linalool loss. FT-IR spectra showed changes that may be related to the formation of intermolecular hydrogen bonds between (−)-linalool and β-CD. The new solid-phase formed using the PM and SC methods, had a crystal structure which was different from the original morphology of β-CD.

A simple temperature method for the estimation of evapotranspiration

Accurate estimation of evapotranspiration (ET) is essential in water resources management and hydrological practices. Estimation of ET in areas, where adequate meteorological data are not available, is one of the challenges faced by water resource managers. Hence, a simplified approach, which is less data intensive, is crucial. The FAO-56 Penman–Monteith (FAO-56 PM) is a sole global standard method, but it requires numerous weather data for the estimation of reference ET. A new simple temperature method is developed, which uses only maximum temperature data to estimate ET. Ten class I weather stations data were collected from the National Meteorological Agency of Ethiopia. This method was compared with the global standard PM method, the observed Piche evaporimeter data, and the well-known Hargreaves (HAR) temperature method. The coefficient of determination (R2) of the new method was as high as 0.74, 0.75, and 0.91, when compared with that of PM reference evapotranspiration (ETo), Piche evaporimeter data, and HAR methods, respectively. The annual average R2 over the ten stations when compared with PM, Piche, and HAR methods were 0.65, 0.67, and 0.84, respectively. The Nash–Sutcliff efficiency of the new method compared with that of PM was as high as 0.67. The method was able to estimate daily ET with an average root mean square error and an average absolute mean error of 0.59 and 0.47 mm, respectively, from the PM ETo method. The method was also tested in dry and wet seasons and found to perform well in both seasons. The average R2 of the new method with the HAR method was 0.82 and 0.84 in dry and wet seasons, respectively. During validation, the average R2 and Nash–Sutcliff values when compared with Piche evaporation were 0.67 and 0.51, respectively. The method could be used for the estimation of daily ETo where there are insufficient data. Copyright © 2013 John Wiley & Sons, Ltd.

A comparison of depletion versus equalization for reducing high‐abundance proteins in human serum

In this work three methods to diminish the content of most highly abundant proteins in human serum have been studied and compared. Protein depletion with ACN or DTT and protein equalization with the ProteoMiner(™) (PM) have been assessed by 1-D gel electrophoresis and MS. After treatment 5, 18 and 9 major proteins within the 20 most abundant proteins in serum were identified for the ACN, DTT and PM methods, respectively. The ACN method was efficient for depleting high molecular weight proteins, over 75 KDa, resulting in 10±4% (n=3) of the total protein content remaining in the depleted serum. In addition, 75% of the proteins belonging to the group of the 20 most abundant proteins were not detected, making this depletion strategy a cheap alternative to expensive commercial tools regularly used for removing high abundance proteins from serum. The ACN extract was found rich in apolipoproteins. The dithithreitol method promotes the precipitation of proteins rich in disulfide bonds, mainly albumin, with 73±7% (n=3) of the total protein content remaining in the depleted serum, which was found rich in immunoglobulins. The PM method compresses the dynamic range of the serum proteins, rendering an extract containing 16±2% (n=3) of the total initial protein content. The extract was found to be rich in both apolipoproteins and immunoglobulins. As a general rule the DTT and PM methods provide a compression of the dynamic range of serum protein concentrations while the ACN method allows an effective depletion of the protein fraction above 72 KDa.

Energy-efficient wireless information retrieval

In this paper, we propose an adaptive application-driven power management (AADPM) protocol for wireless information retrieval applications within the IEEE 802.11b infrastructure WLAN environment. Our goal is to minimize energy consumption while achieving low round trip time delay. We discuss the protocol and evaluate its effectiveness using the network simulator NS2. We also draw horizontal comparisons among a variety of PM methods reported in the literature. Experimental results show that, compared to the power save mode supported by 802.11b, AADPM reduces the network interface card energy consumption by 52% while only introducing 3% RTT delay.

Comparison on PM methods and casting to make aluminium matrix composites with TiAl particles : V. Amigo et al. (Polytechnic University of Valencia, Valencia, Spain.)

Comparison on PM methods and casting to make aluminium matrix composites with TiAl particles : V. Amigo et al. (Polytechnic University of Valencia, Valencia, Spain.)

99/02807 In-stack condensible particulate matter measurement and permitting issues

Based on the results of recent epidemiological studies and assessments of the causes of visibility degradation, EPA is proposing to regulate PM2.5 emissions. PM can be classified as either filterable or condensible PM. Condensible PM includes sulfates, such as sulfuric acid. Sulfates typically account for at least half of the total dry fine PM mass in the atmosphere. Power plant SO{sub x}-based emissions make a significant contribution to ambient fine PM levels in the eastern US. Although much of this mass is derived from secondary chemical reactions in the atmosphere, a portion of this sulfate is emitted directly from stacks as condensible PM. The potential condensible PM fraction associated with coal-burning boiler emissions is somewhat uncertain. The characterization of PM emissions from these sources has been, until recently, based on in-stack filterable PM measurements only. To determine the relative magnitude of condensible PM emissions and better understand condensible PM measurement issues, a review and analysis of actual EPA Method 202 results and state-developed hybrid condensible PM methods were conducted. A review of available Method 202 results for several coal-burning boilers showed that the condensible PM, on average, comprises 60% of the total PM10. A review of recent results for state-developedmore » measurement methods for condensible PM for numerous coal-burning boilers indicated that condensible PM accounted for, on average, approximately 49% of total PM. Caution should be exercised in the use of these results because of the seemingly unresolved issue of artifact formation, which may bias the Method 202 and state-developed methods results on the high side. Condensible PM10 measurement results and issues, and potential ramifications of including condensible PM10 emissions in the PSD permit review process are discussed. Selected power plants in Maryland are discussed as examples.« less

The need for life‐cycle integration of project processes

The focus of this paper is on life‐cycle objective‐based project management systems in general, and SPMIS in particular. SPMIS (short for Smart Project Management Information System), has been designed: (a) to facilitate the employment of life‐cycle objective‐based project management approaches; and (b) to support concurrent engineering and construction, thus promoting greater integration of the processes under which projects are proposed and implemented. In order to validate the functions designed for SPMIS the authors undertook a detailed case study of a large capital project. The actual project management functions employed by the project team on the case project were researched and charted using the best current PM practices as the guide. While this field research shed light on the actual needs and requirements, the design of the SPMIS functions was approached from first principles in order to incorporate the basic shift from the traditional objectives of cost, time, and quality to life‐cycle objective functions, such as return on investment, facility operability, and life‐cycle integration. This paper describes the fundamental philosophy and framework for the development of life‐cycle objective function‐based project management systems in general, and contrasts these with the existing PM methods.

Research Watch: PM methods comparison

ADVERTISEMENT RETURN TO ISSUEPREVDepartmentsNEXTResearch Watch: PM methods comparison Measurements Cite this: Environ. Sci. Technol. 1997, 31, 9, 397APublication Date (Web):June 8, 2011Publication History Published online8 June 2011Published inissue 1 September 1997https://doi.org/10.1021/es9724396RIGHTS & PERMISSIONSArticle Views21Altmetric-Citations-LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (1 MB) Get e-AlertsSUBJECTS:Particulate matter Get e-Alerts

Evaluation of the TEOM® Method for Measurement of Ambient Particulate Mass in Urban Areas

Increased interest in the health effects of ambient par–ticulate mass (PM) has focused attention on the evaluation of existing mass measurement methodologies and the definition of PM in ambient air. The Rupprecht and Patashnick Tapered Element Oscillating MicroBalance (TEOM®) method for PM is compared with time–integrated gravimetric (manual) PM methods in large urban areas during different seasons. Comparisons are conducted for both PM10 and PM2.5 concentrations. In urban areas, a substantial fraction of ambient PM can be semi–volatile material. A larger fraction of this component of PM10 may be lost from the TEOM–heated filter than the Federal Reference Method (FRM). The observed relationship between TEOM and FRM methods varied widely among sites and seasons. In East Coast urban areas during the summer, the methods were highly correlated with good agreement. In the winter, correlation was somewhat lower, with TEOM PM concentrations generally lower than the FRM. Rubidoux, CA, and two Mexican sites (Tlalnepantla and Merced) had the highest levels of PM10 and the largest difference between TEOM and manual methods. PM2.5 data from collocation of 24–hour manual samples with the TEOM are also presented. As most of the semi–volatile PM is in the fine fraction, differences between these methods are larger for PM2.5 than for PM10.