PM Type Research Articles

Micro-Morphological Characteristics and Size Distribution of PM2.5 in the Kuitun-Dushanzi Region of Xinjiang, China

The micro-morphological characteristics of PM_(2.5), collected in the Kuitun-Dushanzi petrochemical area of the Xinjiang Uygur Autonomous Region, China, were studied using a high-resolution field emission scanning electron microscope with energy dispersive X-ray spectroscopy (FESEM-EDX). The individual particle types of PM_(2.5) were identified, including mineral particles (regular minerals and irregular minerals), spherical particles (coal-fired fly ash and some secondary particles), soot aggregates, and other particles (some particles remained unclassified). Factories, power plants, vehicle emissions, and road dust were major sources of PM_(2.5) in the Kuitun-Dushanzi petrochemical area. Vehicle exhaust and waste gas from a power plant were defined as primary sources of mineral particles. Wind speed in September which was higher than July during the sampling time leads to the lower concentration of regular mineral particles since high wind speeds would reduce the chance of secondary particle generation. As a high wind speed would also easily diffuse the fine particles, the coarse-grained mineral particles had the highest percentages in September; the chain-like soot aggregates and the compact soot aggregates were the majority of all kinds of particles. The sizes of various particles in July and September primarily ranged from 0.1 to 0.5 μm.

Automotive Electric Motors, Generators, and Actuator Drive Systems With Reduced or No Permanent Magnets and Innovative Design Concepts

Due to environmental and energy concerns, electric vehicles (EVs) and hybrid EVs (HEVs) are gaining increased attention. At the heart of the drive system of these vehicles is the electric machine and drive. For these applications, high power density, high torque density, wide speed range, and efficiency are of primary importance. To meet these demands, interior-permanent-magnet (IPM) machines have been widely used. However, IPM machines use rare-earth PMs (usually neodymium-iron-boron magnets) in their structure. The price of these types of rare-earth PMs has increased by orders of magnitude over several years. Due to the high cost and limited supply of this material, the use of IPM machines in HEV applications is now being challenged. In fact, many researchers are working on other machines that can compete with IPM machines in terms of size, efficiency, power, and torque density. With consideration of the above points, there is a timeliness to this important topic; thus, we are pleased to present this Special Section on Automotive Electric Motors, Generators, and Actuator Drive Systems With Reduced or No Permanent Magnets and Innovative Design Concepts of the IEEE Transactions on Industrial Electronics that consists of 12 papers reporting on the most recent research on automotive electric drive machines. Most of these papers focus on machines with less or no rare-earth PM material in their structure, although control is also important, and there are some papers related to this topic.

Unbalance response analysis and experimental validation of an ultra high speed motor-generator for microturbine generators considering balancing.

The objective of the present study was to deal with the rotordynamics of the rotor of an ultra-high speed PM type synchronous motor-generator for a 500 W rated micro gas turbine generator. This paper introduces dynamic analysis, and experiments on the motor-generator. The focus is placed on an analytical approach considering the mechanical dynamic problems. It is essential to deal with dynamic stability at ultra-high speeds. Unbalance response analysis is performed by calculating the unbalance with and without balancing using a balancing machine. Critical speed analysis is performed to determine the operating speed with sufficient separation margin. The unbalance response analysis is compared with the experimental results considering the balancing grade (ISO 1940-1) and predicted vibration displacement with and without balancing. Based on these results, a high-speed motor-generator was successfully developed.

The Differences Between an Internal and External Project Manager

The differences between an Internal and External Project Manager (IPM & EPM) are usually overlooked in the project management literature. However these differences may have a significant importance when selecting a project manager, having possible adverse impact on the overall project performance if these differences are not properly considered. This paper elaborates a framework for the differences between an IPM and EPM and tests it against three organisations using quantitative (survey) and qualitative (semi-structured interviews) research methods. The research concludes that both types of PMs should not be viewed within the same light, as they each have a different role, skillset, issue management style and project success rate. In particular, IPMs tend to deploy a more ‘reactive’, whereas EPMs tend to use a more ‘proactive’ management style. Also, moving from IPM to EPM is frequently seen as a career progression. These differences may have major implications on how project managers are selected, promoted and recruited.

Cost-Effectiveness Comparison of Coaxial Magnetic Gears With Different Magnet Materials

This paper presents a comparative study between the nonrare-earth PM and rare-earth PM-based coaxial magnetic gears. First, using finite-element analysis, the electromagnetic performances of four coaxial magnetic gears, which are installed with nonrare- or rare-earth PMs, are analyzed and quantitatively compared based on the same structure. Then, the natural magnetic properties of nonrare- and rare-earth PMs are evaluated and discussed. Finally, the cost effectiveness of coaxial magnetic gears adopting different types of PMs is assessed. The results show that the nonrare-earth PMs, especially the aluminum-nickel-cobalt, are preferred for application to coaxial magnetic gears with emphasis on the cost effectiveness.

The Different Effects of PM Types, Motivation, and Task Sequence on Prospective Memory

The Different Effects of PM Types, Motivation, and Task Sequence on Prospective Memory

Indoor–outdoor concentrations of particulate matter in nine microenvironments of a mix-use commercial building in megacity Delhi

Three naturally and six mechanically ventilated microenvironments (MEs) of a mix-use commercial building in Delhi are used to study indoor–outdoor (I/O) relationships of particulate matter ≤10 μm (PM10), ≤2.5 μm (PM2.5), and ≤1 μm (PM1). Effect of environmental and occupancy parameters on the concentrations of PM during working and non-working hours (i.e., activity and non-activity periods, respectively) are also investigated. Average outdoor concentration of PM10 and PM2.5 were found to exceed the 24-h averaged national standard values, showing a polluted environment surrounding the studied building. During working hours, indoor PM10 concentration was found 6–10 times, both PM2.5 and PM1 were 1.5–2 times, higher than the non-working hours in the selected MEs. The variations of indoor concentrations were highest (17.1–601.2 μg/m3) for PM10 compared with PM2.5 (16.9–102.6 μg/m3) and PM1.0 (10.6–63.6 μg/m3). The I/O for PM10, PM2.5, and PM1.0 varied from 0.37–3.1, 0.2–3.2, and 0.17–2.9, respectively. The results suggest highest I/O for PM10, PM2.5, and PM1 as 3.1, 2.15, and 1.76, respectively, in all the three natural-ventilated MEs (canteen, kitchen, reception). Irrespective of PM types, the average I/O was 1 for naturally ventilated MEs. As opposed to PM1, better correlation (r > 0.6) was noted between indoor PM10, PM2.5, and CO2 concentrations in most of the airtight MEs.

Patients with bipolar disorders share similar but attenuated prospective memory impairments with patients with schizophrenia

Prospective memory (PM) refers to the ability to remember to carry out an intended action in the future. PM is consistently found to be impaired in individuals with schizophrenia. Bipolar disorder and schizophrenia may represent conditions along a continuum, and share similar neurocognitive and genetic architecture. This study aimed to compare the nature and extent of PM impairment in individuals with schizophrenia and bipolar disorder. Participants were 38 out-patients with schizophrenia and 40 out-patients with bipolar disorder in an early psychosis intervention programme, and 37 healthy controls. Time-, event- and activity-based PMs were assessed using a dual-task laboratory paradigm. Self-reported PM performance was gauged using the Prospective and Retrospective Memory Questionnaire. Analysis of covariance (ANCOVA), with intelligence quotient (IQ) and education included as covariates, was used to examine group difference on various types of PM. Repeated measures of ANCOVA were used to examine the group × PM type interaction effect. Correspondence between laboratory and self-reported PM measures was examined using correlational analysis. The group × PM type interaction effect was not significant, but the main effect of group was significant. Patients with schizophrenia and patients with bipolar disorder both performed more poorly than healthy participants in PM. The two clinical groups did not significantly differ in PM. Laboratory and self-reported PM measures did not correlate significantly with each other. Patients with bipolar disorder shared a similar PM impairment with those with schizophrenia. Findings of this study extended the similarity in neurocognitive impairments between the two psychiatric disorders to PM.

The Application of NdFeB in the Magnetic Force Actuator

In this paper, NdFeB is used to design a new type of magnetic force actuator (MFA) with simple structure and high reliability. The permanent magnets are fixed on the static iron-core to generate a magnetic field, while the movable part locates within the magnetic field. It can drive the arc extinguishing unit powered by the Lorentz force, and this can be applied to the operation of the long-stroke high voltage circuit breaker (HVCB). At the open and closed position, the PMs generate holding force for the moving iron-core to keep the static state. Then, the finite element method(FEM) and prototype test are adopted to study the properties of PM and characteristics of the actuator. The simulation concludes that the material type and structure size of PM, end cap material and processing deviation of the actuator will impact the static characteristic of the actuator. The results of the test on prototype show that MFA using NdFeB can achieve the high power output, which is conductive for electronic control as well as the displacement tracking. Due to its stable performance, NdFeB is reliable in the running of the magnetic force actuator.

Weight Reduction Design of In-Wheel type Motor For Power density Improvement

This paper deals with the weight reduction design of In-Wheel type motor for high power density. Accordingly, characteristic and weight of the motor caused by modifying reduction gear ratio are examined. Weight of motor is minimized by modulating the ratio of stack length and external diameter of stator. Then, In-Wheel motor geometry based on the prototype is optimized to get the determined parameters using response surface methodology (RSM) and Finite Element Method (FEM). Optimal design of core usage in rotor is conducted for minimizing weight of motor which has identical characteristic to the prototype. Characteristic analysis is conducted by using equivalent circuit analysis of PM type motor. Through the presented weight of In-Wheel type motor, total weight is reduced to 25%, and power density is improved to 57% from the prototype motor.

CHALLENGES AND OPPORTUNITIES OF ELECTRIC MACHINES FOR RENEWABLE ENERGY

This paper gives an overview of various electric machines for application to renewable energy harvesting, and reveals the corresponding challenges and research opportunities. After introducing various renewable energies and electric machines, the concept of renewable energy machines is coined. Then, the existing machines, including the DC, induction and synchronous types, for renewable energy harvesting are challenged. Consequently, research opportunities of advanced machines, including the stator-permanent magnet (PM), direct-drive PM and magnetless types, are elaborated. Finally, both near-term and long-term renewable energy machines are identifled especially the emerging stator-PM, vernier PM and stator doubly fed doubly salient types.

Prospective memory in patients with first-onset schizophrenia and their non-psychotic siblings

This behavioral study used a dual-task paradigm to compare PM performance in 35 patients with first-onset schizophrenia, 40 non-psychotic siblings and 35 healthy controls. It aimed specifically to examine the effect of schizophrenia group status on PM, the differential effect of group status on PM type, and correlations between PM and other neurocognitive functions and clinical data in first-onset schizophrenia. It also aimed to test the hypothesis that non-psychotic siblings had poorer PM performance than controls. The cohort of first-onset schizophrenia patients had relatively short illness durations (M=1.7 years). The three groups of participants were matched in terms of age, gender and years of education. Results of the study confirmed that first-onset schizophrenia status had a primary effect on PM after controlling for other neurocognitive functions. We also found that first-onset schizophrenia status did not differentially affect two different types of PM. In the first-onset schizophrenia cohort, PM was found to correlate significantly with IQ, executive functions and sustained attention. Finally, contrary to the findings of the previous study, this study did not find siblings of schizophrenia patients to have impaired PM. Taking into account the previous findings of PM in chronic schizophrenia, we concluded that schizophrenia has a primary effect on PM regardless of illness duration.

Spatial and temporal variability of fine particle composition and source types in five cities of Connecticut and Massachusetts

To protect public health from PM 2.5 air pollution, it is critical to identify the source types of PM 2.5 mass and chemical components associated with higher risks of adverse health outcomes. Source apportionment modeling using Positive Matrix Factorization (PMF), was used to identify PM 2.5 source types and quantify the source contributions to PM 2.5 in five cities of Connecticut and Massachusetts. Spatial and temporal variability of PM 2.5 mass, components and source contributions were investigated. PMF analysis identified five source types: regional pollution as traced by sulfur, motor vehicle, road dust, oil combustion and sea salt. The sulfur-related regional pollution and traffic source type were major contributors to PM 2.5. Due to sparse ground-level PM 2.5 monitoring sites, current epidemiological studies are susceptible to exposure measurement errors. The higher correlations in concentrations and source contributions between different locations suggest less spatial variability, resulting in less exposure measurement errors. When concentrations and/or contributions were compared to regional averages, correlations were generally higher than between-site correlations. This suggests that for assigning exposures for health effects studies, using regional average concentrations or contributions from several PM 2.5 monitors is more reliable than using data from the nearest central monitor.

Rotor Shape Design of an Interior PM Type BLDC Motor for Improving Mechanical Vibration and EMI Characteristics

This paper presents the rotor shape optimization of an interior type permanent magnet (IPM) motor for a reduction of vibration and Electromagnetic Interference (EMI). The vibration and EMI in permanent magnet motors is generated by cogging torque ripple, radial force and commutation torque ripple. Consequently, in order to improve vibration and EMI, the optimal notches are put on the rotor pole with an arc shape proposed. The variation of vibration frequency due to the cogging torque and radial force of each model is computed by the finite element method (FEM). From the analysis result and experiment, we confirmed the proposed model has remarkably improved the vibration and EMI.

A empirical study of the effects of supervisory behaviors of PM type on productivity and morale in an organization

A empirical study of the effects of supervisory behaviors of PM type on productivity and morale in an organization

Toward a standardised thermal-optical protocol for measuring atmospheric organic and elemental carbon: the EUSAAR protocol

Abstract. Thermal-optical analysis is a conventional method for determining the carbonaceous aerosol fraction and for classifying it into organic carbon, OC, and elemental carbon, EC. Unfortunately, the different thermal evolution protocols in use can result in a wide elemental carbon-to-total carbon variation by up to a factor of five. In Europe, there is currently no standard procedure for determining the carbonaceous aerosol fraction which implies that data from different laboratories at various sites are of unknown accuracy and cannot be considered comparable. In the framework of the EU-project EUSAAR (European Supersites for Atmospheric Aerosol Research), a comprehensive study has been carried out to identify the causes of differences in the EC measured using different thermal evolution protocols; thereby the major positive and negative biases affecting thermal-optical analysis have been isolated and minimised to define an optimised protocol suitable for European aerosols. Our approach to improve the accuracy of the discrimination between OC and EC was essentially based on four goals. Firstly, charring corrections rely on faulty assumptions – e.g. pyrolytic carbon is considered to evolve completely before native EC throughout the analysis –, thus we have reduced pyrolysis to a minimum by favoring volatilisation of OC. Secondly, we have minimised the potential negative bias in EC determination due to early evolution of light absorbing carbon species at higher temperatures in the He-mode, including both native EC and combinations of native EC and pyrolytic carbon potentially with different specific attenuation cross section values. Thirdly, we have minimised the potential positive bias in EC determination resulting from the incomplete evolution of OC during the He-mode which then evolves during the He/O2-mode, potentially after the split point. Finally, we have minimised the uncertainty due to the position of the OC/EC split point on the FID response profile by introducing multiple desorption steps in the He/O2-mode. Based on different types of carbonaceous PM encountered across Europe, we have defined an optimised thermal evolution protocol, the EUSAAR_2 protocol, as follows: step 1 in He, 200 °C for 120 s; step 2 in He 300 °C for 150 s; step 3 in He 450 °C for 180 s; step 4 in He 650 °C for 180 s. For steps 1–4 in He/O2, the conditions are 500 °C for 120 s, 550 °C for 120 s, 700 ° C for 70 s, and 850 °C for 80 s, respectively.

Cardiovascular health and particulate vehicular emissions: a critical evaluation of the evidence

A major public health goal is to determine linkages between specific pollution sources and adverse health outcomes. This paper provides an integrative evaluation of the database examining effects of vehicular emissions, such as black carbon (BC), carbonaceous gasses, and ultrafine PM, on cardiovascular (CV) morbidity and mortality. Less than a decade ago, few epidemiological studies had examined effects of traffic emissions specifically on these health endpoints. In 2002, the first of many studies emerged finding significantly higher risks of CV morbidity and mortality for people living in close proximity to major roadways, vs. those living further away. Abundant epidemiological studies now link exposure to vehicular emissions, characterized in many different ways, with CV health endpoints such as cardiopulmonary and ischemic heart disease and circulatory-disease-associated mortality; incidence of coronary artery disease; acute myocardial infarction; survival after heart failure; emergency CV hospital admissions; and markers of atherosclerosis. We identify numerous in vitro, in vivo, and human panel studies elucidating mechanisms which could explain many of these cardiovascular morbidity and mortality associations. These include: oxidative stress, inflammation, lipoperoxidation and atherosclerosis, change in heart rate variability (HRV), arrhythmias, ST-segment depression, and changes in vascular function (such as brachial arterial caliber and blood pressure). Panel studies with accurate exposure information, examining effects of ambient components of vehicular emissions on susceptible human subjects, appear to confirm these mechanisms. Together, this body of evidence supports biological mechanisms which can explain the various CV epidemiological findings. Based upon these studies, the research base suggests that vehicular emissions are a major environmental cause of cardiovascular mortality and morbidity in the United States. As a means to reduce the public health consequences of such emissions, it may be desirable to promulgate a black carbon (BC) PM2.5 standard under the National Ambient Air Quality Standards, which would apply to both on and off-road diesels. Two specific critical research needs are identified. One is to continue research on health effects of vehicular emissions, gaseous as well as particulate. The second is to utilize identical or nearly identical research designs in studies using accurate exposure metrics to determine whether other major PM pollutant sources and types may also underlie the specific health effects found in this evaluation for vehicular emissions.

Involvement of TLR2 and TLR4 in inflammatory immune responses induced by fine and coarse ambient air particulate matter

Induction of proinflammatory mediators by alveolar macrophages exposed to ambient air particulate matter has been suggested to be a key factor in the pathogenesis of inflammatory and allergic diseases in the lungs. However, receptors and mechanisms underlying these responses have not been fully elucidated. In this study, we examined whether TLR2, TLR4, and the key adaptor protein, MyD88, mediate the expression of proinflammatory cytokines and chemokines by mouse peritoneal macrophages exposed to fine and coarse PM. TLR2 deficiency blunted macrophage TNF-alpha and IL-6 expression in response to fine (PM2.5), while not affecting cytokine-inducing ability of coarse NIST Standard Reference Material (SRM 1648) particles. In contrast, TLR4(-/-) macrophages showed inhibited cytokine expression upon stimulation with NIST SRM 1648 but exhibited normal responses to PM2.5. Preincubation with polymyxin B markedly suppressed the capacity of NIST SRM 1648 to elicit TNF-alpha and IL-6, indicating endotoxin as a principal inducer of cytokine responses. Overexpression of TLR2 in TLR2/4-deficient human embryonic kidney 293 cells imparted PM2.5 sensitivity, as judged by IL-8 gene expression, whereas NIST SRM 1648, but not PM2.5 elicited IL-8 expression in 293/TLR4/MD-2 transfectants. Engagement of TLR4 by NIST SRM 1648 induced MyD88-independent expression of the chemokine RANTES, while TLR2-reactive NIST IRM PM2.5 failed to up-regulate this response. Consistent with the shared use of MyD88 by TLR2 and TLR4, cytokine responses of MyD88(-/-) macrophages to both types of air PM were significantly reduced. These data indicate differential utilization of TLR2 and TLR4 but shared use of MyD88 by fine and coarse air pollution particles.

Development and Application of Parallel PM Type Hybrid Magnetic Bearings

Development and Application of Parallel PM Type Hybrid Magnetic Bearings

440 磁束集束ローレンツ浮上モータの提案

440 磁束集束ローレンツ浮上モータの提案