Driver Frequency Research Articles

On measuring selection in cancer from subclonal mutation frequencies.

Recently available cancer sequencing data have revealed a complex view of the cancer genome containing a multitude of mutations, including drivers responsible for cancer progression and neutral passengers. Measuring selection in cancer and distinguishing drivers from passengers have important implications for development of novel treatment strategies. It has recently been argued that a third of cancers are evolving neutrally, as their mutational frequency spectrum follows a 1/f power law expected from neutral evolution in a particular intermediate frequency range. We study a stochastic model of cancer evolution and derive a formula for the probability distribution of the cancer cell frequency of a subclonal driver, demonstrating that driver frequency is biased towards 0 and 1. We show that it is difficult to capture a driver mutation at an intermediate frequency, and thus the calling of neutrality due to a lack of such driver will significantly overestimate the number of neutrally evolving tumors. Our approach provides quantification of the validity of the 1/f statistic across the entire range of relevant parameter values. We also show that our conclusions remain valid for non-exponential models: spatial 3d model and sigmoidal growth, relevant for early- and late stages of cancer growth.

Analytical Model for the Breakdown Voltage in Punch-through IGBTs

Insulated-gate bipolar-transistors (IGBTs) are becoming the main switching devices in medium- and high-power applications, such as switched-mode power supplies, power switches, variable frequency driver circuits, traction motors, and inducting heating. Although the switching speed of IGBTs is lower than in the case of metal-oxide-semiconductor field-effect-transistors (MOSFETs), the forward voltage drop is significantly lower, particularly in higher blocking voltage rated devices, which provides major advantage for using IGBTs in many applications. In addition, IGBTs have higher breakdown voltage and currant handling capacity than traditional bipolar-junction-transistors (BJTs), which makes them attractive for a variety of applications related to electric power switches. In this presentation, we introduce two new analytical models for the breakdown voltage of the punch-through IGBTs. The models are based on the accurate analytical estimation of the ionization integral and the solution of the Poisson equation in the drift region, which lead to a nonlinear equation for the breakdown voltage as a function of the doping concentrations in the drift region, buffer layer, and gate and emitter junctions, as well as of the widths of these regions and junctions. In general, this equation does not have an analytical solution and needs to be solved numerically in order to compute the breakdown voltage. Analytical solutions can be found only in a number of particular cases that will be discussed at the conference. The numerical and analytical solutions of the breakdown voltages are compared to more accurate results obtained using Synopsys’s Sentaurus Device Simulator [1], which is a commercial-grade finite element semiconductor simulator. We observe a very good agreement between our models and the finite element simulations for a wide range doping concentration and geometric dimensions of the IGBTs. In addition, at the conference, we will also compare our analytical results with previous analytical results published in the literature [2]. The proposed analytical model provides an efficient way to design the geometry and doping concentration profiles in punch-through IGBTs and helps the optimization process of the breakdown voltage in these devices [3]. More details about the approximations used in our analytical calculations, the results of the comparison with the more precise finite element simulations, and the existing literature will be presented at the conference. [1] 2016 Sentaurus Device Simulator User Manual, www.synopsys.com[2] J. Baliga, Fundamentals of Power Semiconductor Devices: Springer, 2008. [3] Zhu, C., & Andrei, P. (2017). Sensitivity of Breakdown Voltage of Power Transistors to Dopant Impurities. ECS Transactions, 80(7), 171-179.

Effects of In-vehicle Information on Driver Blink Characteristics and Workload

A real-vehicle experiment was carried out to study the effects of in-vehicle information on driver workload, during which data of the driver blink duration and frequency were collected to check for discrepancies among drivers with and without vehicle navigation usage. In the meanwhile, the blink characteristics of drivers with vehicle navigation device mounted at three different positions were explored through image prompt or image & sound multi-channel simultaneous prompt. Experimental results showed that when the data of blink with a duration of 0-200ms was distributed at a 10ms interval, the driver blink count distribution curve shows obvious bimodal characteristics. The peak of blink with 50-60ms duration was lower than that with 10-20ms duration when vehicle navigation was not used, and higher when vehicle navigation was used. The difference between medium and long blinks was not significant when the navigation device was mounted at different positions, yet the short blinks showed a significant difference. The peaks of blink count without voice navigation were all greater than those with voice navigation. In particular, without voice navigation, the short blinks increased obviously, and the medium blinks increased relatively, but the long blinks remained almost unchanged. The above results indicate that the driver workload was greater when using vehicle navigation. When the navigation device is installed in position B, the driver workload reaches the minimum. Using voice navigation could reduce driver workload.

Soft computing applications in the field of industrial and environmental enterprises

Soft computing applications in the field of industrial and environmental enterprises

Development of an Android Based SCADA System for Induction Motor Application

Majority of SCADA (Supervisory Control and Data Acquisition) systems that is being deployed and implemented all over the world utilizes a much larger network that is complex and expensive. This paper provides and demonstrates a cheaper alternative. The developed system which may be used for domestic applications has the ability to monitor the supply voltage, speed, casing and stator temperature as well as to control the speed of the motor. It can transmit the data of these monitored parameters, wirelessly, between the base station (site) and mobile station (android phone) through Bluetooth. The mobile station serves as the display medium to enable the user to view these parameters and also have input keypads that the user can use to alter the speed. To achieve this, an embedded system was used which involves the programming of PIC microcontrollers using assembly language. Other discrete components such as resistor, capacitor, transistors etc. were also utilized. A variable frequency driver was designed to drive the induction motor and interface with the microcontroller. After the design, construction and testing, the results were satisfactory as the SCADA system could alter induction motor speeds, collate motor casing and stator temperature, supply voltage and speed in revolutions per minute (RPM) and transmit them to the android phone. Temperature range of 24ºC to 51ºC, motor speed of 747 to 2234 RPM, and supply voltage of 179 to 221V AC was measured.

Who’s in the driver’s seat? Impact on social participation and psychosocial wellbeing in adults aged 50 and over

Social participation is important to maintain physical and mental wellbeing in older age. We examined how transport mode and current driving status affects social participation and psychosocial wellbeing. Data were collected from 8092 community-dwelling adults aged ≥50 years in The Irish Longitudinal Study on Ageing (TILDA), a nationally representative cohort study. Regression analysis was used, examining associations between transport mode and driving status with depressive symptoms, quality of life, loneliness, monthly involvement in active social leisure activities and volunteering and social network strength. 89.8% of adults travel most frequently by car; 72.2% drive themselves. Driving, being driven by a spouse/partner and taking public transport were independently associated with better indicators of social participation and psychosocial wellbeing versus relying on lifts from family/friends. Non-drivers and less frequent drivers had poorer outcomes versus current drivers. These results highlight the importance of being able to travel independently whether by car or public transport. Opportunities to support this should be considered when planning future transport needs of ageing populations.

Alcohol, Driving, and Health among Community-dwelling Older Adults.

The purpose of this investigation was to examine the relationships among alcohol use, driving behavior, and indicators of health among older adults. A sample of 818 adults ages 65 and older were recruited through the state motor vehicle administration and completed an online survey. Regression models were used to assess the associations between alcohol use, driving behaviors, and 6 health indicators. Whereas more frequent alcohol use was associated with fewer health conditions, higher quantity alcohol use was associated with increased likelihood of having at least one health condition. Participants who drove several days a week and those who drove every day had higher perceived health status, a lower number of past-year health conditions, and a lower number of past-year health events when compared to less frequent drivers. Persons who had at least one past-year negative driving behavior or event were significantly less likely to have positive health status, had lower perceived health status, and had a higher number of past-year health conditions and events. High quantity alcohol use and risky driving behavior among older adults are indicative of poorer health. Continued efforts are needed to educate older adults on the relationships among alcohol use, driving behavior, and health.

Abstract 865: Isolation of circulating tumors cells from genetically engineered mouse models of lung adenocarcinoma

Abstract The major cause of cancer-associated mortality is tumor metastasis, but our understanding of this process is far from complete. During successful dissemination, tumor cells invade the surrounding tissue of the primary tumor, intravasate into blood and lymphatic vessels, translocate to distant tissues, extravasate, adapt to the new microenvironment, and eventually seed, proliferate, and colonize to form metastases. Because dissemination mostly occurs through the blood, circulating tumor cells (CTCs) that have been shed into the vasculature and may be on their way to potential metastatic sites are of obvious interest (1). KRAS mutations are the most frequent oncogenic drivers of non-small cell lung cancer and when associated with co-mutations lead to a decrease in overall survival. We have previously established a lenti-Cre-induced Kras and Lkb1 mutant and Kras and p53 mutant genetically engineered mouse modes (KLLenti) and (KPLenti) that develop 100% lung adenocarcinoma to conduct the first study to isolate and maintain primary, CTC and metastatic cells that are KLLenti or KPLenti. We are able to isolate TTF-1+ and pan-cytokeratin+ CTCs from the KLlenti and KPlenti mice and validated their mutational status by genotyping, western blot, and immunofluorescence. Moreover, lkb1-mutant or p53-mutant primary tumor cells have different 3-D invasive properties and patterns, as well as the respective CTCs and metastatic cells when compared across different genetic sub-types. To further study gene expression patterns between primary, CTC, and metastatic sites RNAseq will be employed to identify pathways that drive metastasis within the genetic sub-types. Citation Format: Liza J. Burton, Junghui Koo, Carol Tucker-Burden, Wei Zhou, Melissa Gilbert-Ross, Chunzi Huang, Gabriel Sica, Adam Marcus. Isolation of circulating tumors cells from genetically engineered mouse models of lung adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 865.

Abstract 582: Tumor immunoediting in a lung cancer mouse model harboring EGFR mutations

Abstract Background: Anti-Programed cell death 1 (PD-1) antibodies such as nivolumab or pembrolizumab show promising treatment effects in smoking-related lung cancer. However, anti-PD-1 antibodies have very little effect on epidermal growth factor receptor (EGFR) mutant non-small cell lung cancer (NSCLC). EGFR mutations are the most frequent oncogenic drivers in non-smoking related NSCLC. Therefore, we aimed to explore the mechanism underlying tumor immunoediting in a lung cancer mouse model harboring EGFR mutations. Methods: We previously established two strains of transgenic lung cancer mouse (C57BL/6) harboring a mouse Egfr exon 19-deletion (mDEL) or a human EGFR L858R (hLR) mutation, driven by a surfactant protein (SP)-C promoter (Ohashi, Cancer Sci. 2008; Ohashi, Cancer Res. 2009). These mice developed EGFR-dependent multifocal lung adenocarcinomas from type II pneumocytes. We modified the two models by transplanting lung tumors subcutaneously into C57BL/6 (Ohashi, AACR. 2018). Evaluation of mice tumor lymphocyte profile was done through flow cytometry or immunohistochemistry (IHC). Effects of T cell depletion or anti-mouse PD-1 antibody (4H2) in vivo were also assessed. Comprehensive analysis of mRNA expression of immuno-checkpoint molecules in the tumors was performed using PanCancer Immune Profiling Panel (NanoString Technologies). Results: CD4+ T cells and/or CD8+ T cells were depleted in the subcutaneously transplanted tumor model followed by treatment with gefitinib (50 mg/kg/day, 5 days/week) for 2 weeks. As a result, after gefitinib discontinuation, rapid regrowth was seen in the tumors from groups with depletion of CD8+ T cells; depletion of CD4+ T cells had little effect on tumor regrowth, and tumor inhibition continued for 2 weeks after cessation of gefitinib. IHC showed relatively increased numbers of CD4+ T cells in the mice tumors whereas a decrease in the number of CD8+ T cells or Foxp3 positive cells was noted. PD-L1 expression was not observed in the tumors. Consistently, 4H2 showed little effect on tumor growth in vivo. The cancer immune panel showed increased expression of immune mediators such as Ccl6, Clec4n, and Lcn2. Conclusions: Our results suggest that CD8+ T cells can recognize mice tumors in vivo. New immuno-checkpoint molecules regulating CD8+ T cells from PanCancer Immune Profiling Panel were evaluated. Further, we plan to evaluate the efficacy of various immuno-checkpoint inhibitors in vivo. Citation Format: Kazuya Nishii, Kadoaki Ohashi, Kiichiro Ninomiya, Go Makimoto, Hiromi Watanabe, Hirohisa Kano, Naofumi Hara, Heiichiro Udono, Katsuyuki Kiura. Tumor immunoediting in a lung cancer mouse model harboring EGFR mutations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 582.

COST EFFECTIVE OPERATION OF HVAC SYSTEM UNDER THERMAL DISTURBANCE

Varying cooling load requirements in HVAC system become a major concern to many consumers because of the additional cost of electricity. The cooling load variation of HVAC system usually occurs when the domestic house door is frequently kept open for prolonged durations, which is particularly important in hot seasons. The present study, addresses a comparison of energy consumption due to the thermal disturbance during domestic house door  keep opened for various duration when the Variable Frequency Driver (VFD) and ON/OFF controllers are installed in HVAC system. The experiments are carried out in two identical houses during six warm days in a hot season where the outdoor temperatures have similar patterns throughout the days. The energy response of HVAC system is analysed incorporating the thermal and the electricity consumption data because of the change of the indoor temperature during opening of the house main door. The cost analysis is carried out and it is extended to include several repeats of door opening durations. It is the first time demonstrated that the energy consumption for HVAC system increases dramatically when the house main door is kept opened for several times in a day. The energy consumption and additional cost increase significantly for the case when the period of the main door opening is extended. In this case, VFD A/C controller unit achieves more energy savings than that of ON/OFF A/C controller unit.

Energy efficiency overestimated by classic affinity laws: relation between volumetric flow rate and static pressure of an axial mine fan adjusted by a variable frequency driver

ABSTRACTA significant problem with operating a coal mine fan is finding ways to save energy while still maintaining the required air supply to working faces. The authors developed and tested the performance of a K45-4-№9/18.5 kW axial mine fan adjusted by a variable frequency driver set to different fractions of a typical national electric grid frequency of 50 Hz. Its volumetric flow-rate and static pressure (Q-H) data were fitted with fifth-order polynomial equations using least-squares regression. The extremes of the Q-H curves descend with decreasing frequency and differ significantly from the predictions of classic affinity laws (CAL) in fluid dynamics. The air-flow power predicted by CAL theory deviates from the baseline of the fifth-order polynomial extremes by a maximum of 48%. Interestingly, the deviation between theoretical and experimental values increases with decreasing power frequency. These results are evidence of the theoretical overestimation of energy efficiency of an AMF adjusted by a VFD.

Do beliefs differ between frequent and infrequent hand-held and hands-free phone users while driving? A Polish study

AimAlthough it is currently legal in Poland to use a hands-free mobile phone while driving, research suggests that it is not significantly safer than using a hand-held mobile phone. The present study used the theory of planned behaviour (TPB) to examine the relationships that three types of beliefs (behavioural, normative and control beliefs) have with the frequency of drivers’ hands-free and hand-held mobile phone use.Subjects and methodsThe sample comprised 298 Polish drivers (35% females) aged between 18 and 40 years old (mean age: 21.05 years, standard deviation = 2.38).ResultsTwo multivariate analyses of variance (MANOVAs) were conducted to investigate the differences between the two groups (hand-held and hands-free) of frequent and infrequent mobile phone users, with regard to their behavioural, normative and control beliefs. Significant differences were found in all of the control beliefs for both hand-held and hands-free mobile phone users. Similar normative differences were identified for both hands-free and hand-held mobile phone use, but while three behavioural beliefs differed significantly for hands-free use, no behavioural beliefs were significant for hand-held mobile phone use. Finally, composite measures of the behavioural and control beliefs were predictive of being a frequent hand-held mobile phone user, but none of the three beliefs were predictive of being a frequent hands-free user.ConclusionsThese results demonstrate potential directions for behavioural change aimed at reducing or preventing the use of mobile phones while driving.

A Compact +10/+5 dBm 800/2600 MHz LTE Driver Amplifier With Ground-Bounce Reduction

A reconfigurable, compact, dual-band radio frequency driver amplifier (DA) is presented. The proposed DA operates in the 800 and 2600 MHz LTE bands using a single inductor for both bands. The single-ended DA demonstrates a ground bounce reduction technique using a series- LC resonant network at the source of the amplifying device, which also improves overall gain. It is fabricated on a TSMC 65-nm CMOS process and measurement results show that it is capable of delivering up to 16.5/14.5 dBm saturated power at a drain efficiency of 35.7%/32.2%. When driven with a 10 MHz 16-QAM LTE signal, it delivers a modulated power of +10/+5 dBm at a drain efficiency of 14.5%/7.5%, and exhibits an ACPR of −40 dBc. The DA consumes a power of 69/42.2 mW from a 2.5-V supply, and occupies an overall area of 0.48 $\text {mm}^{{2}}$ .

Comparing drivers’ visual attention at Junctions in Real and Simulated Environments

Driving simulation is widely used to answer important applied research questions, however, it is vital for specific driving tasks to undergo appropriate behavioural validation testing. Many previous validation studies have used simple driving tasks and measured relatively low-level vehicle control. The purpose of the current study was to investigate whether drivers’ visual attention at intersections with different levels of demand, are similar in the simulator and on the road. Unlike simpler driving tasks, crossing intersections requires complex interactions with other vehicles governed by sequences of head and eye movements that may not be accurately captured in a simulated environment.In the current study we directly compare performance at simulated junctions with the same participants' behaviour in a real car. We compared drivers’ visual attention in a high-fidelity driving simulator (instrumented car, 360-degree screen) and on-road in both low and medium demand driving situations. The low and medium demand driving situations involved the same motor movements, containing straight on, right turn and left turn manoeuvres. The low demand situations were controlled by the road environment and traffic lights, whereas medium demand situations required the driver to scan the environment and decide when it was safe to pull out into the junction. Natural junctions in Nottingham were used for the on-road phase and the same junctions were recreated in the simulator with traffic levels matched to those that were encountered on the real roads.The frequency and size of drivers' head movements were not significantly different between manoeuvres performed in the simulator and those conducted when driving on real roads. This suggests that drivers' broad search strategies in the simulator are representative of real-world driving. These strategies did change as a function of task demand - compared to low demand situations, behaviour at the medium demand junctions was characterised by longer junction crossing times, more head movements, shorter fixation durations and larger saccadic amplitudes. Although patterns of head movements were equivalent on road and in the simulator, there were differences in more fine-grained measures of eye-movements. Mean fixation durations were longer in the simulator compared to on-road, particularly in low-demand situations. We interpret this as evidence for lower levels of visual engagement with the simulated environment compared to the real world, at least when the task demands are low. These results have important implications for driving research. They suggest that high fidelity driving simulators can be useful tools for investigating drivers’ visual attention at junctions, particularly when the driving task is of at least moderate demand.

Frequent versus occasional drivers: A hybrid route choice model

Previous route choice studies have mostly focused on the effect of observable factors, such as route attributes and socio-economic characteristics, on individuals’ decisions. However, route choice decisions might not be exclusively dependent on these observable variables, but also on latent variables, which cannot be directly observed and measured. Also, the latent behavioral heterogeneity among the population has mostly been ignored by assuming that all the individuals in the sample population have similar attitudes, perceptions, and lifestyles.In this paper, we present a comprehensive framework to explicitly incorporate latent behavioral constructs as well as segment heterogeneity based on a probabilistic segmentation of the population. We apply the proposed framework to compare the route choice behavior of frequent versus occasional drivers. An Integrated Choice and Latent Variable model is used to bring in the role of the underlying behavioral constructs, while a Latent Class model accounts for taste heterogeneity across the two segments of our sample population. An Extended Path-Size Logit model is adopted as the choice model component and a Metropolis-Hastings based algorithm is used to generate route alternatives. Data is collected through a web-based survey designed to collect behavioral data on drivers’ route choices, using psychometric indicators and behavioral questions on respondents’ perceptions and attitudes. Results confirm that the inclusion of latent variables and latent heterogeneity across population segments significantly improve the explanatory power of the choice model, and illustrate how the route choice behavior of frequent car users is different from that of occasional ones.

Coronal Loop Transverse Oscillations Excited by Different Driver Frequencies

Abstract We analyze transverse oscillations of a coronal loop excited by continuous monoperiodic motions of the loop footpoint at different frequencies in the presence of gravity. Using the MPI-AMRVAC code, we perform three-dimensional numerical magnetohydrodynamic simulations, considering the loop as a magnetic flux tube filled in with denser, hotter, and gravitationally stratified plasma. We show the resonant response of the loop to its external excitation and analyze the development of the Kelvin–Helmholtz instability at different heights. We also study the spatial distribution of plasma heating due to transverse oscillations along the loop. The positions of the maximum heating are in total agreement with those for the intensity of the Kelvin–Helmholtz instability, and correspond to the standing wave antinodes in the resonant cases. The initial temperature configuration and plasma mixing effect appear to play a significant role in plasma heating by transverse footpoint motions. In particular, the development of the Kelvin–Helmholtz instability in a hotter loop results in the enhancement of the mean plasma temperature in the domain.

The effects of rebranding on customer-based brand equity

The luxury fashion market is predicted to continue to grow rapidly, as millennial are becoming the new luxury consumers. Differentiation from competitors, attracting new consumers, and continuously maintaining brand equity is more challenging than ever, especially for global brands. The purpose of this study is to explore the drivers and process of rebranding and its influence on brand awareness and customer-based brand equity within the luxury fashion market. This study adopts a multi-method qualitative approach, employing semi-structured interviews with practitioners, consumer-based focus groups, and semiotics - in order to measure the impact of rebranding processes on customer-based brand equity. The findings outline the most frequent drivers and the crucial steps of a rebranding process for the luxury market. Radical and moderate changes can be made to the brand image and further support customer-based brand equity, yet, it is vital to remain true to the original heritage and brand's DNA.

The effects of rebranding on customer-based brand equity

The luxury fashion market is predicted to continue to grow rapidly, as millennial are becoming the new luxury consumers. Differentiation from competitors, attracting new consumers, and continuously maintaining brand equity is more challenging than ever, especially for global brands. The purpose of this study is to explore the drivers and process of rebranding and its influence on brand awareness and customer-based brand equity within the luxury fashion market. This study adopts a multi-method qualitative approach, employing semi-structured interviews with practitioners, consumer-based focus groups, and semiotics - in order to measure the impact of rebranding processes on customer-based brand equity. The findings outline the most frequent drivers and the crucial steps of a rebranding process for the luxury market. Radical and moderate changes can be made to the brand image and further support customer-based brand equity, yet, it is vital to remain true to the original heritage and brand's DNA.

The Variable Neighborhood Search for a Consistent Vehicle Routing Problem under the Shift Length Constraints

This paper addresses a new real-world application of vehicle routing planning in a finite time horizon. A company in the small package shipping industry has a limited fleet of identical vehicles in some depots and must serve a set of clients. There is a frequency for each client stating how often this client must be visited. Time intervals between two consecutive visits must be the same but the visiting schedule is flexible. To get some competitive advantage, a company tries to increase the service quality. To this end, each client should be visited by one driver only. The goal is to minimize the total traveling distance for all vehicles over the planning horizon under the frequency constraints and driver shift length constraints. We present an integer linear programming model for this new consistent vehicle routing problem. To find near optimal solutions, we design the Variable Neighborhood Search metaheuristic with nine neighborhood structures. The driver shift length constraints are penalized and included in the objective function. Empirical results for real test instances from Orenburg region in Russia with up to 900 clients and four weeks in the planning horizon are discussed.

Implementation of green manufacturing concepts: a case study of tea manufacturing industry in Sri Lanka

The objective of this study is to identify the potential implementation of green manufacturing concepts on medium scale tea industries in Sri Lanka. Five medium scale tea factories located in southern province were selected as the sample and case study approach was followed. The data were collected through regular factory observations and secondary sources including published reports and documents of the companies. Material and energy flow diagram was used as the main tool for the analysis. The result reveals that there are significant environmental issues such as large-scale raw material wastage, and high level of energy, water consumption and harmful emissions. This study suggests that energy consumption can be reduced by introducing new equipment, methods and systems such as installing variable speed motors, power factor correction capacitors, variable frequency drivers, replacing light emitting diodes (LEDs) with compact fluorescents, implementing well-planned production schedules, and fixing net metering system and solar panels.