Academic literature on the topic 'Signals and signaling, Automobile Research'
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Journal articles on the topic "Signals and signaling, Automobile Research"
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Horvat, Rajko, Berislav Barišić-Jaman, Gordan Mršić, Igor Špoljarić, Andro Vrdoljak, and Ivan Pehar. "Method of Light Bulbs Analysis on Vehicles Damaged in Traffic Accidents." PROMET - Traffic&Transportation 22, no. 4 (March 1, 2012): 259–71. http://dx.doi.org/10.7307/ptt.v22i4.191.
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One of the measures to increase road traffic safety in Croatia is the introduction of obligatory use of daily lights on vehicles in road traffic during driving, regardless of the visibility and the time of day. The paper describes the new original technical and technological procedure of analysing automotive light bulbs in order to find the traces of glass particles of the broken glass balloon in the marginal cases of action of small inertia forces generated as result of a traffic accident. Investigations of light bulbs in traffic accidents had been rarely done before; therefore the subject of this scientific research is the analysis of the light bulb filament used in automobiles to light the road ahead and to give light signals, i.e. all the light signalling devices on the automobile using the new technical and technological procedure by means of SEM/EDX method. The scientific research has improved the investigation procedure in analysing the light bulbs on automobiles in determining whether at the moment of the traffic accident the regulatory lights were switched on. In determining the responsibility of participants for causing the traffic accident, such a fact may sometimes be of crucial significance. KEY WORDS: traffic accident, light bulb, technical and technological procedure, lights in traffic, microscope, molten glass particles
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Sivak, Michael, Michael Flannagan, and Paul L. Olson. "Brake Lamp Photometrics and Automobile Rear Signaling." Human Factors: The Journal of the Human Factors and Ergonomics Society 29, no. 5 (October 1987): 533–40. http://dx.doi.org/10.1177/001872088702900503.
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The objective of this study was to evaluate the relationship of lamp photometrics to differentiation between brake and presence signals. To assess this relationship, signal identification was evaluated as a function of lamp photometrics under simulated dusk/dawn conditions. The following were the main results: (1) Luminous intensity was a better predictor of signal identification than was average luminance. (2) The likelihood of identifying a signal as a brake signal was a monotonic function of lamp intensity. (3) Reaction time was positively related to the degree of subjects' uncertainty (as measured by the relative likelihood of “brake” responses): reaction time was slowest when the likelihood of “brake” or “presence” responses was close to 50%, and it decreased as the likelihood increased or decreased away from 50%. (4) Reaction time in a condition simulating typical U.S. rear-lighting configuration was significantly faster than in a condition simulating typical European configuration. The present results provide support for retaining luminous intensity as the relevant parameter of automobile brake-lighting specifications. Furthermore, these results argue against reducing the current minimum of 80 cd for the brake-lamp luminous intensity.
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Yu, Miao, Lu Shuai, Jiang Wei Guo, and Jie Fu. "Research on Environmental Durability Testing System for Automobile Engine ECU." Applied Mechanics and Materials 121-126 (October 2011): 2855–59. http://dx.doi.org/10.4028/www.scientific.net/amm.121-126.2855.
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Based on the principle and specifications of Environmental Durability Test on automobile engine ECU, an open, intelligent and practical ECU durability testing system (EDTS) is designed. The system consisted of a simulation platform and a testing management software. The platform provided stimulating sensor signals and simulation loads, and an online automotive environment was built. The management software sent various instructions to set up the platform and read the ECU running status data. And this EDTS has been applied to test a kind of domestic automobile engine ECU．The experimental results shows that the mean time to failure (MTTF) of ECU samples was improved and the testing period was shortened greatly.
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Song, Xiedong, and Wei Yang. "Research on the Sound Quality Evaluation Method Based on Artificial Neural Network." Scientific Programming 2022 (May 5, 2022): 1–8. http://dx.doi.org/10.1155/2022/8686785.
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For the improvement of the traditional evaluation effect of the automobile sound quality, an evaluation model of automobile sound quality is constructed based on BP neural network. The first is to introduce the basic principle of the BP neural network in detail. The second is to use the MGC parameters to establish the vehicle interior sound conversion model. The converted sound characteristic parameters are taken into the WORLD model to synthesize the new sound signals. Furthermore, the wavelet decomposition method is used to remove noise from the synthesized sound signals. Finally, a sound evaluation model based on BP neural network is established. The sound quality of automobiles can be better evaluated by carrying out the ABX test and MOS test in the field of sound conversion. For the newly synthesized sound signal and the target sound signal, it can be seen that the newly synthesized sound signal is more inclined to the target sound signal, and the sound quality is better. In addition, the sound quality is tested through loudness, roughness, sharpness, and level A in the field of sound quality evaluation. The final results show that the quality of newly synthesized sound is better, and the average errors of sound signals meet the sound standard. Therefore, the constructed sound conversion model and the sound evaluation model are feasible and effective.
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Luo, Yan Jie, Jia Chen Li, and Yun Fei Mai. "Simulation and Inertial Force Research of Three-Channel Hydraulic Loading Test Bench." Applied Mechanics and Materials 543-547 (March 2014): 1331–34. http://dx.doi.org/10.4028/www.scientific.net/amm.543-547.1331.
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This paper states the control principle of the three-channel hydraulic loading test bench for automobile steering gear test. The test bench model considering inertial force is constructed and simulated. The Integral-Separated PID control algorithm is adopted to optimize control effect and the respond features of the input signals are analyzed. The simulation results show that the system works steadily, the accuracy of synchronization control is better and the tracking control achieves well.
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Shkrabak, Roman Vladimirovich. "Device for automatic determination of inclination angles of means of mechani-zation of technological processes in agro-industrial complex." Agrarian Scientific Journal, no. 5 (May 26, 2021): 103–6. http://dx.doi.org/10.28983/asj.y2021i5pp103-106.
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The article describes the problem associated with the loss of stability of means of mechanization of agro-industrial processes by machine-tractor units (transport, stealing, automobile and automobile trains, combines, and lifting cranes). It is noted that this circumstance leads to overturns, accidents, injuries, fires, often accompanied by fatalities. In support of the above, information is summarized on the number of injuries among women and men in the country's agro-industrial enterprises (including lethal ones). It is noted that this is due to the fact that these units are not equipped with devices that signal, automatically notify operators operating in conditions of irregularities in the terrain of fields and roads (mountainous areas) about the achievements of maximum inclination angles, the excess of which leads to overturns. In order to eliminate these situations, a device is justified and based on extensive research, automatically signalling and visually and soundly about reaching the limit angles (for a given machine) of stability in order to take measures by the operator to prevent overturning. Equipping these machines with the proposed innovative device will eliminate the possibility of overturns and related accidents, injuries, fires, providing a socio-economic effect.
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Kharouf, Husni, Donald J. Lund, Alexandra Krallman, and Chris Pullig. "A signaling theory approach to relationship recovery." European Journal of Marketing 54, no. 9 (June 30, 2020): 2139–70. http://dx.doi.org/10.1108/ejm-10-2019-0751.
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Purpose Drawing on signaling theory, the purpose of this study is to investigate the effects of the strength and framing of firm signals sent to repair relationships following relationship violations. Design/methodology/approach Three 2 × 2 scenario-based experiments (total n = 527) manipulate signal strength × violation type (Study 1); signal frame × violation type (Study 2); and signal strength × brand familiarity (Study 3) to examine their dynamic impacts on relationship recovery efforts. Findings Stronger signals are more effective at relationship repair and are especially important following integrity (vs competence) violations. Signals framed as customer gains (vs firm costs) lead to more favorable relationship outcomes. Finally, brands that are less (vs more) familiar see greater benefits from strong signals. Research limitations/implications The three experiments were scenario-based, which may not replicate real-life behavior or capture participants’ actual emotions following a violation, thus future research should extend into real-world recovery efforts. Practical implications Managers should send strong signals (communicating the level of resources invested in the recovery efforts) framed as benefits to the customer, rather than costs to the firm. Strong signals are especially important when brand familiarity is low or an integrity violation has occurred. Originality/value This is the first research to directly apply signaling theory to the relationship recovery process and contributes to theory by examining the role of signal strength; framing of the signal as a customer gain vs firm cost; and the interplay of signal strength and brand familiarity on the relationship recovery effort.
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Jacob, Stefan, Sri Bühring, and Katharina Bersching. "Recent Advances in Research on Molecular Mechanisms of Fungal Signaling." Encyclopedia 2, no. 2 (April 21, 2022): 840–63. http://dx.doi.org/10.3390/encyclopedia2020055.
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Biochemical signaling is one of the key mechanisms to coordinate a living organism in all aspects of its life. It is still enigmatic how exactly cells and organisms deal with environmental signals and irritations precisely because of the limited number of signaling proteins and a multitude of transitions inside and outside the cell. Many components of signaling pathways are functionally pleiotropic, which means they have several functions. A single stimulus often results in multiple responses, a distinct response can be triggered by numerous stimuli and signals initiated by different stimuli are often transduced via commonly used network components. This review sheds light on the most important molecular mechanisms of cellular signaling in fungi and consequently provides a comprehensive overview about the current state of research on the road to understand the impact of signal transduction in eukaryotic microorganisms.
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Du, Canyi, Rui Zhong, Yishen Zhuo, Xinyu Zhang, Feifei Yu, Feng Li, Ying Rong, and Yongkang Gong. "Research on fault diagnosis of automobile engines based on the deep learning 1D-CNN method." Engineering Research Express 4, no. 1 (January 14, 2022): 015003. http://dx.doi.org/10.1088/2631-8695/ac4834.
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Abstract Traditional engine fault diagnosis methods usually need to extract the features manually before classifying them by the pattern recognition method, which makes it difficult to solve the end-to-end fault diagnosis problem. In recent years, deep learning has been applied in different fields, bringing considerable convenience to technological change, and its application in the automotive field also has many applications, such as image recognition, language processing, and assisted driving. In this paper, a one-dimensional convolutional neural network (1D-CNN) in deep learning is used to process vibration signals to achieve fault diagnosis and classification. By collecting the vibration signal data of different engine working conditions, the collected data are organized into several sets of data in a working cycle, which are divided into a training sample set and a test sample set. Then, a one-dimensional convolutional neural network model is built in Python to allow the feature filter (convolution kernel) to learn the data from the training set and these convolution checks process the input data of the test set. Convolution and pooling extract features to output to a new space, which is characterized by learning features directly from the original vibration signals and completing fault diagnosis. The experimental results show that the pattern recognition method based on a one-dimensional convolutional neural network can be effectively applied to engine fault diagnosis and has higher diagnostic accuracy than traditional methods.
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Colombo, Oskar. "The Use of Signals in New-Venture Financing: A Review and Research Agenda." Journal of Management 47, no. 1 (March 24, 2020): 237–59. http://dx.doi.org/10.1177/0149206320911090.
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The use of signals to overcome information asymmetries and reduce the uncertainty inherent in resource acquisition has become a prominent theme in new-venture financing literature. In particular, the assessment of a wide range of different information signals, with the aim of conveying a venture’s quality and legitimacy to prospective investors, is receiving increased scholarly attention. With contributions from a broad spectrum of diverse research foci investigating interactions with distinct types of investors, the literature on entrepreneurial signaling in new-venture financing has become fragmented, and this is harming further development of the field. This study systematically reviews the different literature streams on entrepreneurial signaling to provide a more integrative framework, which can contribute to the cumulative and evidence-based body of knowledge about the role of entrepreneurial signaling in new-venture financing. Furthermore, the authors identify critical sender-, signal-, receiver-, and environment-related boundary conditions that influence the signaling effectiveness. In this way, the authors identify gaps in the existing literature and map directions for future research.
Dissertations / Theses on the topic "Signals and signaling, Automobile Research"
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Lavik, Andrew R. "The Role of Inositol 1,4,5-Trisphosphate Receptor-Interacting Proteins in Regulating Inositol 1,4,5-Trisphosphate Receptor-Dependent Calcium Signals and Cell Survival." Case Western Reserve University School of Graduate Studies / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=case1448532307.
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Jiang, Zhaoning Zheng Jim P. "Luminous intensity measurements for LED related traffic signals and signs." 2004. http://etd.lib.fsu.edu/theses/available/etd-04122004-152617.
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Thesis (M.S.)--Florida State University, 2004.Advisor: Dr. Jim P. Zheng, Florida State University, College of Engineering, Dept. of Electrical and Computer Engineering. Title and description from dissertation home page (viewed June 18, 2004). Includes bibliographical references.
Books on the topic "Signals and signaling, Automobile Research"
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Signals and boundaries: Building blocks for complex adaptive systems. Cambridge, Mass: MIT Press, 2012.
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Portanova, Anthony D. Report of the Flashing Light Task Force: Pursuant to P.A. 03-265, including findings and recommendations. Hartford, Conn: Flashing Light Task Force, 2004.
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Institution of Mechanical Engineers (Great Britain). Automobile Division., Institution of Electrical Engineers, and Autotech 95 (1995), eds. Automotive systems, sensors, and signalling: Selected papers from Autotech 95, 7-9 November 1995. London: Published by Mechanical Engineering Publications for the Institution of Mechanical Engineers, 1996.
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Hoffman, Donald D., Burkard Wördenweber, Jörg Wallaschek, and Peter Boyce. Automotive Lighting and Human Vision. Springer, 2010.
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Hoffman, Donald D., Burkard Wördenweber, Jörg Wallaschek, and Peter Boyce. Automotive Lighting and Human Vision. Springer, 2007.
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Automotive Lighting and Human Vision. Springer, 2007.
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Publishers), PEP (Professional Engineering. Automotive Systems, Sensors and Signalling (Autotech '95) (IMechE Seminar Publications). Wiley, 1996.
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United States. Navy Dept. and United States. Office of the Chief of Naval Operations., eds. Final overseas environmental impact statement and environmental impact statement for surveillance towed array sensor system low frequency active (SURTASS LFA) sonar. Arlington, VA: Dept. of the Navy, 2001.
Find full textBook chapters on the topic "Signals and signaling, Automobile Research"
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Dunlop, Rebecca, William L. Gannon, Marthe Kiley-Worthington, Peggy S. M. Hill, Andreas Wessel, and Jeanette A. Thomas. "Vibrational and Acoustic Communication in Animals." In Exploring Animal Behavior Through Sound: Volume 1, 389–417. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-97540-1_11.
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AbstractAn introduction to acoustic and vibrational communication in animals is presented in this chapter. Starting with the origins of communication and ritualization of vocal and vibrational signals to produce a clear message or broadcast. A summary of communication concepts is presented describing behaviors such as displays. The chapter continues by unraveling some of the complexities of acoustic and vibrational communication such as elephant vibration detection posture and reception of long-range vibrational signal production—or drumming—in Prairie chickens and Kangaroo rats. We discuss the advantages of vibrational and acoustic signal production signals as well as the disadvantages including the influence of environmental factors that may mask or attenuate signals such as wind, water, or structural clutter. Research on the informational content of these signals is progressing. We provide a summary of ground-breaking earlier work, an indication of where we believe the field is now, and a glimpse of where we believe the field could be going in the future. The chapter concludes with a discussion of the characteristics of human language and whether nonhuman animals have such a language with the accompanying mental abilities. It could just be that other animals are most entertained (and threatened!) by our signaling behaviors.
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Orian-Rousseau, Véronique, and Jonathan Sleeman. "CD44 is a Multidomain Signaling Platform that Integrates Extracellular Matrix Cues with Growth Factor and Cytokine Signals." In Advances in Cancer Research, 231–54. Elsevier, 2014. http://dx.doi.org/10.1016/b978-0-12-800092-2.00009-5.
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San-Martín, Sonia. "Are Signals a Solution to Perceived Risk and Opportunism in Mobile Shopping?" In Advances in E-Business Research, 1–24. IGI Global, 2015. http://dx.doi.org/10.4018/978-1-4666-7262-8.ch001.
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There is usually a situation of information asymmetry in mobile shopping. According to signaling theory and applying it to a mobile commerce context, the authors propose a model with some cognitive and experiential quality signals from the vendor and the site that can reduce shopper perceived risk and fear of opportunism: vendor reputation, site design, personalized service, and personalized information. However, as some literature states that male and female behaviour is somewhat different, the authors analyze differences and similarities between men and women in those perceptions of signals, risk, and opportunism. The authors collected information from 447 mobile shoppers, and results show some gender differences, which involve implications for managers when segmenting their potential market of mobile shoppers by gender. Women are more sensitive to signals, whereas for men the reduction of risk is key to less perceived opportunism.
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Kimery, Kathryn M., and Mary McCord. "Signals of Trustworthiness in E-Commerce." In Information Security and Ethics, 272–91. IGI Global, 2008. http://dx.doi.org/10.4018/978-1-59904-937-3.ch021.
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Signaling theory provides the framework to address three main research questions: (1) How accurately do consumers notice and recollect TPA seals on retail Web sites? (2) How familiar are consumers with major TPA seals? and (3) How accurately do consumers understand the assurances represented by the TPA seals? Results of this study of three major TPA seals (TRUSTe, BBBOnLine Reliability, and VeriSign) reveal that subjects have poor recall of TPA seals viewed on a Web site, have limited familiarity with TPA programs, and have incomplete and largely inaccurate perceptions of the assurances that TPA seals represent. These results suggest that TPA seals may not fulfill their potential to influence consumer trust in e-commerce because the signals are not noticed on merchant Web sites or adequately understood by consumers.
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Troise, Ciro. "Multiple Signals and Consumer Behavior in the Digital Economy." In Leveraging Consumer Behavior and Psychology in the Digital Economy, 1–26. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-3042-9.ch001.
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The digital economy shows a challenging environment, and three main players have entered the arena (digital platforms, online communities, new technologies). The aim of this chapter is to provide a new multidimensional framework for exploring multiple signals. The study leverages the signaling theory, since signals help companies and sellers to mitigate information asymmetries. In the virtual context of the digital economy, credible and observable information improve the decision-making process of consumers. The work opted for a multidimensional framework and proposes that four types of signals (social network, social capital, certification, social identity) influence consumer behavior. Furthermore, the study suggests that also the interactions/combinations between these signals could affect consumer behavior. This contribution offers a conceptual framework without testing empirically the propositions; thus, it offers the opportunity of further research. This work has interesting implications for several actors of the digital ecosystem (firms, entrepreneurs, platform managers, consumers, etc.).
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Boateng, Sheena Lovia. "Enhancing Calculative Commitment and Customer Loyalty Through Online Relationship Marketing." In Research Anthology on E-Commerce Adoption, Models, and Applications for Modern Business, 1221–41. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-8957-1.ch063.
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This study examines the mediating role of online trust in enhancing calculative commitment and customer loyalty through online relationship marketing activities (engagement and interactivity). The study draws on signaling theory. Data were gathered from 429 retail bank customers in Ghana and analyzed using confirmatory factor analysis and structural path modelling. Findings suggest that engagement is assessed to be low by Ghanaian bank customers and presently has no influence on customer commitment, online trust, and customer loyalty. However, signals communicated through interactivity online is of great benefit to the banks in influencing customers' online trust, as well as their calculative commitment and loyalty. Further, though, website and email emerged as the most predominant technologies used in online relationship marketing (ORM), customers also expect banks to engage with them through social media, which has the potential to improve upon the current levels of ORM activities.
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Macêdo, Francelma Maria de Moura, Jamerson Viegas Queiroz, Zulmara Virgínia de Carvalho, and Cristiano Alves. "Creativity Processes Applied to the Innovation Management of a Digital Showroom for Cars." In Interdisciplinary and Practical Approaches to Managerial Education and Training, 229–42. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-7998-8239-8.ch013.
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The COVID-19 pandemic has profoundly impacted the Brazilian service sector. With the health crisis, challenges and changes in the business models of car dealerships are also intensified. Creativity is discussed by several conceptual approaches. From the point of view of neuroscience, it is a response to the human need of solving problems. It is within this premise that the present work aims to enhance value proposition for a business model centered on automobile e-commerce. This purpose unfolds in an exploratory research on approaches, methodologies, and tools of creativity, as well as the application of Cristiano Alves's creative framework in this business model. The analysis of the results signals improvements in solutions for car e-commerce. With this, it is concluded that collective creativity is efficient in the discovery of potentially innovative ideas.
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Maharaj, Gyanpriya, Godfrey Bourne, and Abdullah Ansari. "A Review of Floral Color Signals and Their Heliconiid Butterfly Receivers." In Arthropods [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.98666.
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Signals vary in type and function. However, regardless of the signal, effective transmission and receiver detection are needed to exist for communication. This chapter focuses on a review of visual color signals used by plants to attract pollinators. Signal detection work has intensely focused on epigamic signals; therefore, this review adds to the body of knowledge on nonsexual signal communication. In this review, we investigate visual signals as it relates to pollinators. We focus specifically on visual color signals used by Angiosperms flowers, both static and dynamic, and look at their Heliconiid pollinators as these butterflies provide a perfect organism for studies on floral signal use and pollinators’ behavior. We noted that many of these butterflies have three specifically distinct rhodopsins used to identify food and oviposition sites and some have more due to selective pressures of conspecific and mate identification as such they have served as the focal organisms of numerous genetic and ecological studies as they use color signaling in all aspects of their lives. This review further shows that although their color preferences related to feeding, ovipositing, and mate selection have been demonstrated in countless studies, there are gaps in invertebrate literature, as research on the relationships among signal use, evolution, dynamic signals, effects of signals changes on decision making and thus behavior have not been carried out to a large extent.
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Kimery, Kathryn M., and Mary McCord. "Seals on Retail Web Sites." In Advances in Electronic Commerce, 111–34. IGI Global, 2008. http://dx.doi.org/10.4018/978-1-59904-822-2.ch007.
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Signaling theory provides the framework to address why third-party assurance (TPA) seals may not have the desired positive effect on consumer trust in online merchants. Based on identified antecedents of effective signaling, three research propositions are presented to explore 1) how reliably consumers are able to recall TPA seals on viewed retail websites, 2) how familiar consumers are with major TPA seals, and 3) how accurately consumers comprehend the assurances legitimately represented by the TPA seals. Results of this study of three major TPA seals (TRUSTe, BBBOnLine Reliability, and VeriSign) reveal that subjects have relatively poor notice and recall of TPA seals viewed on a website, have limited familiarity with TPA programs, and have incomplete and largely inaccurate understanding of the assurances represented by the TPA seals. These results suggest that TPA seals may not fulfill their potential to influence consumer trust in online merchants, because the signals are not effectively noticed or accurately interpreted by consumers.
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Benarroch, Eduardo E. "Growth Factors, Survival, and Regeneration." In Neuroscience for Clinicians, edited by Eduardo E. Benarroch, 213–30. Oxford University Press, 2021. http://dx.doi.org/10.1093/med/9780190948894.003.0013.
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Neurotrophic factors and hypoxia-inducible factors participate in fundamental processes including growth, differentiation, survival, and plasticity in the nervous system. They activate downstream cascades that promote protein synthesis and inhibit cell death mechanisms of apoptosis and autophagy. Axonal injury triggers retrograde neurotrophic signaling to the nucleus to regulate transcription of genes involved in axonal repair. Hypoxia induces expression of genes that control angiogenesis, erythropoiesis, and glycolysis. Growth factor and hypoxia-inducible signals are regulated by products of tumor suppressor genes. Excessive activation of these pathways lead to genetic tumor syndromes, many of them associated with epilepsy. Experimental models indicate that growth factors have neuroprotective effects against neurodegeneration. However, several human studies using growth factors administered systemically or via genetic methods have so far failed to show consistent beneficial effects. This has been attributed to inadequate dosing and delivery and enrollment of patients at late stage of disease. Approaches to promote axonal regeneration by targeting are an active area of research.
Conference papers on the topic "Signals and signaling, Automobile Research"
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Sinyavski, V. V., M. G. Shatrov, A. Y. Dunin, I. G. Shishlov, and A. V. Vakulenko. "Results of Simulation and Experimental Research of Automobile Gas Diesel Engine." In 2019 Systems of Signals Generating and Processing in the Field of on Board Communications. IEEE, 2019. http://dx.doi.org/10.1109/sosg.2019.8706756.
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Dilli, Zeynep, Nuttiiya Seekhao, and John C. Rodgers. "An introduction to the evaluation of the effects of high power microwave signals on signaling systems." In 2011 International Semiconductor Device Research Symposium (ISDRS). IEEE, 2011. http://dx.doi.org/10.1109/isdrs.2011.6135358.
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Merat, Kaveh, Jafar Abbaszadeh Chekan, Hassan Salarieh, and Aria Alasty. "Online Hybrid Model Predictive Controller Design for Cruise Control of Automobiles." In ASME 2017 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/dscc2017-5274.
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In the proposed study, a Hybrid Model Predictive Controller is introduced for cruise control of an automobile model. The presented model consists of the engine, the gearbox, and the transmission dynamics, where the aerodynamics force and elastic friction between the tires and road are taken into account. Through Piecewise Linearization of nonlinearities in the system; (torque)-(throttle)-(angular velocity) of engine and (aerodynamic drag force)-(automobile velocity), a comprehensive piecewise linear model for the system is obtained. Then combined with the switch and shift between engaged gears in gearbox, the Piecewise Affine (PWA) model for the vehicle dynamics is acquired. As far as the control design is concerned, the cruise control problem for tracking a desired speed fashion is addressed by a MPC-based controller design. The proposed control approach is based on the online model predictive control, applied on the obtained PWA dynamics. The highlighted novelties of the presented research work are summarized as: first a more complete model is examined due to the consideration of a realistic model for engine. This improvement makes the polyhedron regions of the PWA system dependent to both state variable (i.e., velocity) and input signals (i.e., throttle and engaged gear) which brings the complexity to the design of control procedure. Second, due to the switch in the dynamics and dependence of our PWA model to discrete input (gear shift), the desperate need to solve the optimization problem through mixed integer programming, which needs high computation effort specially for our system, seems inevitable. We triumph over this challenge through introducing “possible gear shift scenario” sets. Hence, by constraining the optimization problem to the introduced logical sets, the problem still remains convex optimization type and the computation volume is reduced. In addition, we hired branch and bound method which allowed us to have large problems to be solved in a tractable amount of time and computation resources. At last, some simulations are presented to exhibit the performance of the proposed method.
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Sanz Bobi, Juan de Dios, Pedro Reyes de la Pen˜a, Jose Carlos Hidalgo Fiestas, Alberto Garci´a de los A´ngeles, and Roberto Loiero. "Sizing Solar Energy Components for Level-Crossing Facilities." In ASME 2008 International Mechanical Engineering Congress and Exposition. ASMEDC, 2008. http://dx.doi.org/10.1115/imece2008-68672.
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Currently, there are a large number of level crossings on railway lines. These signaling facilities are necessary from the point of view of railway lines and also from the traffic of vehicles and people crossing them. This signaling system is built on a number of elements such as acoustic and lighting signals—barriers that prevent cars & pedestrians from accessing rail tracks. These level crossing facilities operate autonomously and they are not part of the security facilities (interlockings) when planning or building stages. Therefore, a major constraint for level crossings is the lack of a feasible electric supply primarily because of the high cost of cable running due to the great difficulty of transporting this energy to some areas. This high cost will make installation unprofitable where there is light traffic in trains and/or pedestrians and vehicles. This paper proposes that a solar photovoltaic supply system would make installation cost efficient instead of cable running. The research shows that the sizing method for this power supply and the measuring tool detailed below ease calculations. This proposed system provides both economical and environmental benefits. These benefits positively impact those areas where traditional cable supply is difficult to provide. In order to size the electrical feeding system for these level crossings facilities two calculations are necessary: 1) the calculation of the daily incident solar irradiation into a horizontal surface and, 2) the location where the facility is going to be set. The calculation of the theoretical energy consumption is determined by the integral of the instantaneous electrical power consumption of the system. Thus, the proposed solution in the paper provides a cost reduction to deploy level crossing facilities crossing existing railway lines. It allows the installation of level crossings with increased security features necessary for the correct signaling from the basic level crossing to configurations such as acoustic and light signals, or even protective barriers. These elements provide more information and safety to cars and pedestrians concerning train crossing, decreasing the risk of accidents. Additionally, this power supply system can be deployed easily and can be adapted to any topology minimizing costs. Furthermore these systems are environmentally friendly as they clear away the impact of the electrical consumption of the facility from the network and do not need cable running in order to transport this energy to the level crossing facility.
Reports on the topic "Signals and signaling, Automobile Research"
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McGuire, Mark A., Amichai Arieli, Israel Bruckental, and Dale E. Bauman. Increasing Mammary Protein Synthesis through Endocrine and Nutritional Signals. United States Department of Agriculture, January 2001. http://dx.doi.org/10.32747/2001.7574338.bard.
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Objectives To determine endocrine factors that regulate the partitioning of amino acids by the mammary gland. To evaluate dietary flow and supply of energy and amino acids and their effects on milk protein synthesis and endocrine status. To use primary cultures of cow mammary epithelial cells to examine the role of specific factors on the rates and pattern of milk protein synthesis. Milk protein is an increasingly valuable component of milk but little is known regarding the specific hormonal and nutritional factors controlling milk protein synthesis. The research conducted for this project has determined that milk protein synthesis has the potential to be enhanced much greater than previously believed. Increases of over 25% in milk protein percent and yield were detected in studies utilizing abomasal infusion of casein and a hyperinsulinemic-euglycemic clamp. Thus, it appears that insulin, either directly or indirectly, can elicit a substantial increase in milk protein synthesis if additional amino acids are supplied. For additional amino acids, casein provided the best response even though substantial decreases in branched chain amino acids occur when the insulin clamp is utilized. Branched chain amino acids alone are incapable of supporting the enhanced milk protein output. The mammary gland can vary both blood flow and extraction efficiency of amino acids to support protein synthesis. A mammary culture system was used to demonstrate specific endocrine effects on milk protein synthesis. Insulin-like growth factor-I when substituted for insulin was able to enhance casein and a-lactalbumin mRNA. This suggests that insulin is a indirect regulator of milk protein synthesis working through the IGF system to control mammary production of casein and a-lactalbumin. Principal component analysis determined that carbohydrate had the greatest effect on milk protein yield with protein supply only having minor effects. Work in cattle determined that the site of digestion of starch did not affect milk composition alone but the degradability of starch and protein in the rumen can interact to alter milk yield. Cows fed diets with a high degree of rumen undegradability failed to specifically enhance milk protein but produced greater milk yield with similar composition. The mammary gland has an amazing ability to produce protein of great value. Research conducted here has demonstrated the unprecedented potential of the metabolic machinery in the mammary gland. Insulin, probably signaling the mammary gland through the IGF system is a key regulator that must be combined with adequate nutrition in order for maximum response.
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Sadot, Einat, Christopher Staiger, and Mohamad Abu-Abied. Studies of Novel Cytoskeletal Regulatory Proteins that are Involved in Abiotic Stress Signaling. United States Department of Agriculture, September 2011. http://dx.doi.org/10.32747/2011.7592652.bard.
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In the original proposal we planned to focus on two proteins related to the actin cytoskeleton: TCH2, a touch-induced calmodulin-like protein which was found by us to interact with the IQ domain of myosin VIII, ATM1; and ERD10, a dehydrin which was found to associate with actin filaments. As reported previously, no other dehydrins were found to interact with actin filaments. In addition so far we were unsuccessful in confirming the interaction of TCH2 with myosin VIII using other methods. In addition, no other myosin light chain candidates were found in a yeast two hybrid survey. Nevertheless we have made a significant progress in our studies of the role of myosins in plant cells. Plant myosins have been implicated in various cellular activities, such as cytoplasmic streaming (1, 2), plasmodesmata function (3-5), organelle movement (6-10), cytokinesis (4, 11, 12), endocytosis (4, 5, 13-15) and targeted RNA transport (16). Plant myosins belong to two main groups of unconventional myosins: myosin XI and myosin VIII, both closely related to myosin V (17-19). The Arabidopsis myosin family contains 17 members: 13 myosin XI and four myosin VIII (19, 20). The data obtained from our research of myosins was published in two papers acknowledging BARD funding. To address whether specific myosins are involved with the motility of specific organelles, we cloned the cDNAs from neck to tail of all 17 Arabidopsis myosins. These were fused to GFP and used as dominant negative mutants that interact with their cargo but are unable to walk along actin filaments. Therefore arrested organelle movement in the presence of such a construct shows that a particular myosin is involved with the movement of that particular organelle. While no mutually exclusive connections between specific myosins and organelles were found, based on overexpression of dominant negative tail constructs, a group of six myosins (XIC, XIE, XIK, XI-I, MYA1 and MYA2) were found to be more important for the motility of Golgi bodies and mitochondria in Nicotiana benthamiana and Nicotiana tabacum (8). Further deep and thorough analysis of myosin XIK revealed a potential regulation by head and tail interaction (Avisar et al., 2011). A similar regulatory mechanism has been reported for animal myosin V and VIIa (21, 22). In was shown that myosin V in the inhibited state is in a folded conformation such that the tail domain interacts with the head domain, inhibiting its ATPase and actinbinding activities. Cargo binding, high Ca2+, and/or phosphorylation may reduce the interaction between the head and tail domains, thus restoring its activity (23). Our collaborative work focuses on the characterization of the head tail interaction of myosin XIK. For this purpose the Israeli group built yeast expression vectors encoding the myosin XIK head. In addition, GST fusions of the wild-type tail as well as a tail mutated in the amino acids that mediate head to tail interaction. These were sent to the US group who is working on the isolation of recombinant proteins and performing the in vitro assays. While stress signals involve changes in Ca2+ levels in plants cells, the cytoplasmic streaming is sensitive to Ca2+. Therefore plant myosin activity is possibly regulated by stress. This finding is directly related to the goal of the original proposal.
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Miller, Gad, and Jeffrey F. Harper. Pollen fertility and the role of ROS and Ca signaling in heat stress tolerance. United States Department of Agriculture, January 2013. http://dx.doi.org/10.32747/2013.7598150.bard.
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The long-term goal of this research is to understand how pollen cope with stress, and identify genes that can be manipulated in crop plants to improve reproductive success during heat stress. The specific aims were to: 1) Compare heat stress dependent changes in gene expression between wild type pollen, and mutants in which pollen are heat sensitive (cngc16) or heat tolerant (apx2-1). 2) Compare cngc16 and apx2 mutants for differences in heat-stress triggered changes in ROS, cNMP, and Ca²⁺ transients. 3) Expand a mutant screen for pollen with increased or decreased thermo-tolerance. These aims were designed to provide novel and fundamental advances to our understanding of stress tolerance in pollen reproductive development, and enable research aimed at improving crop plants to be more productive under conditions of heat stress. Background: Each year crop yields are severely impacted by a variety of stress conditions, including heat, cold, drought, hypoxia, and salt. Reproductive development in flowering plants is highly sensitive to hot or cold temperatures, with even a single hot day or cold night sometimes being fatal to reproductive success. In many plants, pollen tube development and fertilization is often the weakest link. Current speculation about global climate change is that most agricultural regions will experience more extreme environmental fluctuations. With the human food supply largely dependent on seeds, it is critical that we consider ways to improve stress tolerance during fertilization. The heat stress response (HSR) has been intensively studied in vegetative tissues, but is poorly understood during reproductive development. A general paradigm is that HS is accompanied by increased production of reactive oxygen species (ROS) and induction of ROS-scavenging enzymes to protect cells from excess oxidative damage. The activation of the HSR has been linked to cytosolic Ca²⁺ signals, and transcriptional and translational responses, including the increased expression of heat shock proteins (HSPs) and antioxidative pathways. The focus of the proposed research was on two mutations, which have been discovered in a collaboration between the Harper and Miller labs, that either increase or decrease reproductive stress tolerance in a model plant, Arabidopsis thaliana (i.e., cngc16--cyclic nucleotide gated channel 16, apx2-1--ascorbate peroxidase 2,). Major conclusions, solutions, achievements. Using RNA-seq technology, the expression profiles of cngc16 and apx2 pollen grains were independently compared to wild type under favourable conditions and following HS. In comparison to a wild type HSR, there were 2,776 differences in the transcriptome response in cngc16 pollen, consistent with a model in which this heat-sensitive mutant fails to enact or maintain a normal wild-type HSR. In a comparison with apx2 pollen, there were 900 differences in the HSR. Some portion of these 900 differences might contribute to an improved HSR in apx2 pollen. Twenty-seven and 42 transcription factor changes, in cngc16 and apx2-1, respectively, were identified that could provide unique contributions to a pollen HSR. While we found that the functional HS-dependent reprogramming of the pollen transcriptome requires specific activity of CNGC16, we identified in apx2 specific activation of flavonol-biosynthesis pathway and auxin signalling that support a role in pollen thermotolerance. Results from this study have identified metabolic pathways and candidate genes of potential use in improving HS tolerance in pollen. Additionally, we developed new FACS-based methodology that can quantify the stress response for individual pollen in a high-throughput fashion. This technology is being adapted for biological screening of crop plant’s pollen to identify novel thermotolerance traits. Implications, both scientific and agricultural. This study has provided a reference data on the pollen HSR from a model plant, and supports a model that the HSR in pollen has many differences compared to vegetative cells. This provides an important foundation for understanding and improving the pollen HSR, and therefor contributes to the long-term goal of improving productivity in crop plants subjected to temperature stress conditions. A specific hypothesis that has emerged from this study is that pollen thermotolerance can be improved by increasing flavonol accumulation before or during a stress response. Efforts to test this hypothesis have been initiated, and if successful have the potential for application with major seed crops such as maize and rice.
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Chamovitz, Daniel, and Xing-Wang Deng. Morphogenesis and Light Signal Transduction in Plants: The p27 Subunit of the COP9-Complex. United States Department of Agriculture, 1997. http://dx.doi.org/10.32747/1997.7580666.bard.
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Plants monitor environmental signals and modulate their growth and development in a manner optimal for the prevailing light conditions. The mechanisms by which plants transduce light signals and integrate them with other environmental and developmental signals to regulate plant pattern development are beginning to be unraveled. A large body of knowledge has accumulated regarding the roles of specific photoreceptors in perceiving light signals, and about the downstream developmental responses responding to light (Batschauer, 1999; Chamovitz and Deng, 1996; Deng and Quail, 1999). Still, little is know about the molecular mechanisms connecting the photoreceptors to development, and how these developmental pathways are integrated with additional developmental regulatory pathways to modulate growth. The multi-subunit protein complex COP9 signalosome (previously referred to as the "COP9 complex") has a central role in mediating the light control of plant development, and in general developmental regulation. Arabidopsis mutants that lack this complex develop photomorphogenically even in the absence of light signals (reviewed in Chamovitz and Deng 1996, 1997). Various genetic studies have indicated that the COP9 signalosome acts at the nexus of upstream signals transduced from the individual photoreceptors, and specific downstream signaling pathways. Thus the COP9 signalosome was hypothesized to be a master repressor of photomorphogenesis, and that light acts to abrogate this repression. However, the COP9 signalosome has roles beyond the regulation of photomorphogenesis as all mutants lacking this complex die following early seedling development, and an essentially identical complex has also been detected in animal systems (Chamovitz and Deng, 1995; Seeger et al., 1998; Wei et al., 1998). Our long term objective is to determine the role of the COP9 signalosome in controlling plant development. In this research project we showed that this complex contains at least eight subunits (Karniol et al., 1998; Serino et al., 1999) and that the 27 kD subunit is encoded by the FUS5 locus (Karniol et al., 1999). The FUS5 subunit also has a role extraneous to the COP9 signalosome, and differential kinase activity has been implicated in regulating FUSS and the COP9 signalosome (Karniol et al., 1999). We have also shown that the COP9 signalosome may work together with the translational-regulator eIF3. Our study of the COP9 signalosome is one of the exciting examples of plant science leading the way to discoveries in basic animal science (Chamovitz and Deng, 1995; Karniol and Chamovitz, 2000; Wei and Deng, 1999).
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Chamovitz, Daniel A., and Xing-Wang Deng. Developmental Regulation and Light Signal Transduction in Plants: The Fus5 Subunit of the Cop9 Signalosome. United States Department of Agriculture, September 2003. http://dx.doi.org/10.32747/2003.7586531.bard.
Full textAbstract:
Plants adjust their growth and development in a manner optimal for the prevailing light conditions. The molecular mechanisms by which light signals are transduced and integrated with other environmental and developmental signals are an area of intense research. (Batschauer, 1999; Quail, 2002) One paradigm emerging from this work is the interconnectedness of discrete physiological responses at the biochemical level, for instance, between auxin and light signaling (Colon-Carmona et al., 2000; Schwechheimer and Deng, 2001; Tian and Reed, 1999) and between light signaling and plant pathogen interactions (Azevedo et al., 2002; Liu et al., 2002). The COP9 signalosome (CSN) protein complex has a central role in the light control of plant development. Arabidopsis mutants that lack this complex develop photomorphogenically even in the absence of light signals (reviewed in (Karniol and Chamovitz, 2000; Schwechheimer and Deng, 2001). Thus the CSN was hypothesized to be a master repressor of photomorphogenesis in darkness, and light acts to bypass or eliminate this repression. However, the CSN regulates more than just photomorphogenesis as all mutants lacking this complex die near the end of seedling development. Moreover, an essentially identical complex was subsequently discovered in animals and yeast, organisms whose development is not light responsive, exemplifying how plant science can lead the way to exciting discoveries in biomedical model species (Chamovitz and Deng, 1995; Freilich et al., 1999; Maytal-Kivity et al., 2002; Mundt et al., 1999; Seeger et al., 1998; Wei et al., 1998). Our long-term objective is to determine mechanistically how the CSN controls plant development. We previously that this complex contains eight subunits (Karniol et al., 1998; Serino et al., 1999) and that the 27 ilia subunit is encoded by the FUS5/CSN7 locus (Karniol et al., 1999). The CSN7 subunit also has a role extraneous to the COP9 signalosome, and differential kinase activity has been implicated in regulating CSN7 and the COP9 signalosome (Karniol et al., 1999). In the present research, we further analyzed CSN7, both in terms of interacting proteins and in terms of kinases that act on CSN7. Furthermore we completed our analysis of the CSN in Arabidopsis by analyzing the remaining subunits. Outline of Original Objectives and Subsequent Modifications The general goal of the proposed research was to study the CSN7 (FUS5) subunit of the COP9 signalosome. To this end we specifically intended to: 1. Identify the residues of CSN7 that are phosphorylated. 2. Monitor the phosphorylation of CSN7 under different environmental conditions and under different genetic backgrounds. 3. Generate transgenic plants with altered CSN7 phosphorylation sites. 4. Purify CSN7 kinase from cauliflower. 5. Clone the Arabidopsis cDNA encoding CSN7 kinase 6. Isolate and characterize additional CSN7 interacting proteins. 7. Characterize the interaction of CSN7 and the COP9 signalosome with the HY5-COP1 transcriptional complex. Throughout the course of the research, emphasis shifted from studying CSN7 phosphorylation (Goals 1-3), to studying the CSN7 kinase (Goal 4 and 5), an in depth analysis of CSN7 interactions (Goal 6), and the study of additional CSN subunits. Goal 7 was also abandoned as no data was found to support this interaction.
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Horwitz, Benjamin, and Nicole M. Donofrio. Identifying unique and overlapping roles of reactive oxygen species in rice blast and Southern corn leaf blight. United States Department of Agriculture, January 2017. http://dx.doi.org/10.32747/2017.7604290.bard.
Full textAbstract:
Plants and their fungal pathogens both produce reactive oxygen species (ROS). CytotoxicROS act both as stressors and signals in the plant-fungal interaction. In biotrophs, a compatible interaction generates little ROS, but is followed by disease. An incompatible interaction results in a strong oxidative burst by the host, limiting infection. Necrotrophs, in contrast, thrive on dead and dying cells in an oxidant-rich local environment. Rice blast, Magnaportheoryzae, a hemibiotroph, occurs worldwide on rice and related hosts and can decimate enough rice each year to feed sixty million people. Cochliobolusheterostrophus, a necrotroph, causes Southern corn leaf blight (SLB), responsible for a major epidemic in the 1970s. The objectives of our study of ROS signaling and response in these two cereal pathogens were: Confocal imaging of ROS production using genetically encoded redox sensor in two pathosystems over time. Forward genetic screening of HyPer sensor lines in two pathosystems for fungal genes involved in altered ROSphenotypes. RNA-seq for discovery of genes involved in ROS-related stress and signaling in two pathosystems. Revisions to the research plan: Library construction in SLB was limited by low transformation efficiency, compounded by a protoplasting enzyme being unavailable during most of year 3. Thus Objective 2 for SLB re-focused to construction of sensor lines carrying deletion mutations in known or candidate genes involved in ROS response. Imaging on rice proved extremely challenging, so mutant screening and imaging were done with a barley-infecting line, already from the first year. In this project, ROS imaging at unprecedented time and spatial resolution was achieved, using genetically-encoded ratio sensors in both pathogens. This technology is currently in use for a large library of rice blast mutants in the ROS sensor background, and Southern corn leaf blight mutants in final stages of construction. The imaging methods developed here to follow the redox state of plant pathogens in the host tissue should be applicable to fungal pathogens in general. Upon completion of mutant construction for SCLB we hope to achieve our goal of comparison between intracellular ROS status and response in hemibiotroph and necrotroph cereal pathogens.
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Delmer, Deborah P., Douglas Johnson, and Alex Levine. The Role of Small Signal Transducing Gtpases in the Regulation of Cell Wall Deposition Patterns in Plants. United States Department of Agriculture, August 1995. http://dx.doi.org/10.32747/1995.7570571.bard.
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The combined research of the groups of Delmer, Levine and Johnson has led to a number of interesting findings with respect to the function of the small GTPase Rac in plants and also opened up new leads for future research. The results have shown: 1) The Rac13 protein undergoes geranylgeranlyation and is also translocated to the plasma membrane as found for Rac in mammals; 2) When cotton Rac13 is highly- expressed in yeast, it leads to an aberrant phenotype reminiscent of mutants impaired in actin function, supporting a role for Rac13 in cytoskeletal organization; 3) From our searches, there is no strong evidence that plants contain homologs of the related CDC42 genes found in yeast and mammals; 4) We have identified a rather unique Rac gene in Arabidopsis that has unusual extensions at both the N- and C-terminal portions of the protein; 5) New evidence was obtained that an oxidative burst characterized by substantial and sustained production of H202 occurs coincident with the onset of secondary wall synthesis in cotton fibers. Further work indicates that the H202 produced may be a signal for the onset of this phase of development and also strongly suggests that Rac plays an important role in signaling for event. Since the secondary walls of plants that contain high levels of lignin and cellulose are the major source of biomass on earth, understanding what signals control this process may well in the future have important implications for manipulating the timing and extent of secondary wall deposition. 6) When the cotton Rac13 promoter is fused to the reporter gene GUS, expression patterns in Arabidopsis indicate very strong and specific expression in developing trichomes and in developing xyelm. Since both of these cell types are engaged in secondary wall synthesis, this further supports a role for Rac in signaling for onset of this process. Since cotton fibers are anatomically defined as trichomes, these data may also be quite useful for future studies in which the trichomes of Arabidopsis may serve as a model for cotton fiber development; the Rac promoter can therefore be useful to drive expression of other genes proposed to affect fiber development and study the effects on the process; 7) The Rac promoter has also been shown to be the best so far tested for use in development of a system for transient transformation of developing cotton fibers, a technique that should have many applications in the field of cotton biotechnology; 8) One candidate protein that may interact with Rac13 to be characterized further in the future is a protein kinase that may be analogous to the PAK kinase that is known to interact with Rac in mammals.
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Or, Etti, David Galbraith, and Anne Fennell. Exploring mechanisms involved in grape bud dormancy: Large-scale analysis of expression reprogramming following controlled dormancy induction and dormancy release. United States Department of Agriculture, December 2002. http://dx.doi.org/10.32747/2002.7587232.bard.
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The timing of dormancy induction and release is very important to the economic production of table grape. Advances in manipulation of dormancy induction and dormancy release are dependent on the establishment of a comprehensive understanding of biological mechanisms involved in bud dormancy. To gain insight into these mechanisms we initiated the research that had two main objectives: A. Analyzing the expression profiles of large subsets of genes, following controlled dormancy induction and dormancy release, and assessing the role of known metabolic pathways, known regulatory genes and novel sequences involved in these processes B. Comparing expression profiles following the perception of various artificial as well as natural signals known to induce dormancy release, and searching for gene showing similar expression patterns, as candidates for further study of pathways having potential to play a central role in dormancy release. We first created targeted EST collections from V. vinifera and V. riparia mature buds. Clones were randomly selected from cDNA libraries prepared following controlled dormancy release and controlled dormancy induction and from respective controls. The entire collection (7920 vinifera and 1194 riparia clones) was sequenced and subjected to bioinformatics analysis, including clustering, annotations and GO classifications. PCR products from the entire collection were used for printing of cDNA microarrays. Bud tissue in general, and the dormant bud in particular, are under-represented within the grape EST database. Accordingly, 59% of the our vinifera EST collection, composed of 5516 unigenes, are not included within the current Vitis TIGR collection and about 22% of these transcripts bear no resemblance to any known plant transcript, corroborating the current need for our targeted EST collection and the bud specific cDNA array. Analysis of the V. riparia sequences yielded 814 unigenes, of which 140 are unique (keilin et al., manuscript, Appendix B). Results from computational expression profiling of the vinifera collection suggest that oxidative stress, calcium signaling, intracellular vesicle trafficking and anaerobic mode of carbohydrate metabolism play a role in the regulation and execution of grape-bud dormancy release. A comprehensive analysis confirmed the induction of transcription from several calcium–signaling related genes following HC treatment, and detected an inhibiting effect of calcium channel blocker and calcium chelator on HC-induced and chilling-induced bud break. It also detected the existence of HC-induced and calcium dependent protein phosphorylation activity. These data suggest, for the first time, that calcium signaling is involved in the mechanism of dormancy release (Pang et al., in preparation). We compared the effects of heat shock (HS) to those detected in buds following HC application and found that HS lead to earlier and higher bud break. We also demonstrated similar temporary reduction in catalase expression and temporary induction of ascorbate peroxidase, glutathione reductase, thioredoxin and glutathione S transferase expression following both treatments. These findings further support the assumption that temporary oxidative stress is part of the mechanism leading to bud break. The temporary induction of sucrose syntase, pyruvate decarboxylase and alcohol dehydrogenase indicate that temporary respiratory stress is developed and suggest that mitochondrial function may be of central importance for that mechanism. These finding, suggesting triggering of identical mechanisms by HS and HC, justified the comparison of expression profiles of HC and HS treated buds, as a tool for the identification of pathways with a central role in dormancy release (Halaly et al., in preparation). RNA samples from buds treated with HS, HC and water were hybridized with the cDNA arrays in an interconnected loop design. Differentially expressed genes from the were selected using R-language package from Bioconductor project called LIMMA and clones showing a significant change following both HS and HC treatments, compared to control, were selected for further analysis. A total of 1541 clones show significant induction, of which 37% have no hit or unknown function and the rest represent 661 genes with identified function. Similarly, out of 1452 clones showing significant reduction, only 53% of the clones have identified function and they represent 573 genes. The 661 induced genes are involved in 445 different molecular functions. About 90% of those functions were classified to 20 categories based on careful survey of the literature. Among other things, it appears that carbohydrate metabolism and mitochondrial function may be of central importance in the mechanism of dormancy release and studies in this direction are ongoing. Analysis of the reduced function is ongoing (Appendix A). A second set of hybridizations was carried out with RNA samples from buds exposed to short photoperiod, leading to induction of bud dormancy, and long photoperiod treatment, as control. Analysis indicated that 42 genes were significant difference between LD and SD and 11 of these were unique.