Direct sequence spread spectrum based PWM strategy for harmonic reduction and communication

Switched mode power supplies (SMPSs) are essential components in many applications, and electromagnetic interference is an important consideration in the SMPS design. Spread spectrum based PWM strategies have been used in SMPS designs to reduce the switching harmonics. This paper proposes a novel method to integrate a communication function into spread spectrum based PWM strategy without extra hardware costs. Direct sequence spread spectrum (DSSS) and phase shift keying (PSK) data modulation are employed to the PWM of the SMPS, so that it has reduced switching harmonics and the input and output power line voltage ripples contain data. A data demodulation algorithm has been developed for receivers, and code division multiple access (CDMA) concept is employed as communication method for a system with multiple SMPSs. The proposed method has been implemented in both Buck and Boost converters. The experimental results validated the proposed DSSS based PWM strategy for both harmonic reduction and communication.

Munkaszervezés a lean termelésben – mit magyaráznak a termelésmenedzsment koncepciók = Work organization in lean production – what production concepts explain

A tanulmány a lean termelés munkaszervezését három termelésmenedzsment koncepció segítségével vizsgálja. Az egyes koncepciók a szervezet eltérő metszeteit érintik: (1) a termék-folyamat mátrix (Hayes és Wheelwright, 1979) a termék és a folyamat jellemzőit helyezi középpontba. A lean hatására a szervezet a mátrixban a nagyobb választék és a folyamat alapú működés (nagyobb függőség) irányába mozdul el. Az elmozdulást üzemi szinten a magas elkötelezettségű munkavégzési rendszer gyakorlatainak bevezetése kíséri, mivel azok támogatják a rugalmas működést, a gyors kommunikációt és problémamegoldást. Az elmozdulás „minősége” és így a munkaszervezési gyakorlatok használata (mélyég, száma, munkavállalók bevonása) nagyban függ a termelési stratégiától és a lean érettségtől. (2) A termelési stratégia szakaszai (Wheelwright és Hayes, 1985) a termelés üzleti stratégiában játszott szerepét elemzik. A lean termelés összeegyeztethető a termelési stratégia harmadik szakaszának „command és control” szemléletmódjával. Az ilyen lean termelők költégfókuszúak, a hagyományos munkaerőképben gondolkodnak és körükben kevésbé jellemző az új emberi erőforrás gyakorlatok használata. A lean termelés adaptálása ösztönözheti a vállalatokat a termelési stratégia negyedik szintje felé. A negyedik szint a bevonásra, problémamegoldásra és tanulásra épít, amely megfelel a lean „emberek tisztelete” pillérének. (3) A lean érettségi modell (Hines és társai, 2004) a lean szervezeten belüli elmélyülését és terjedését mutatja be. A lean utazás során a vállalatok az eszköz alapú megközelítéstől a komplex értékrendszerben gondolkodó lean szervezet felé haladnak. A technikai tudásanyag egyre szélesebb körűvé válik, ami rávilágít a tudásátadás (személyek közöttire, de akár struktúrákba, folyamatokba építése is) képességének jelentőségére. Az emberi erőforrás gyakorlatok folyamatosan jelennek meg. De csak a legfejlettebb szakasz, a lean tanuló szervezet megjelenése teszi valóban szükségessé a munkavállalói kép újragondolását is. = This paper examines work organization in lean production with the help of three production concepts. These concepts embrace different dimensions of the organization: (1) the product-process matrix (Hayes and Wheelwright, 1979) is about product and process characteristics. Due to the lean the organization shifts within the matrix – towards higher variability and flow (higher level of interdependencies). On the shop floor the shift is accompanied by the introduction of high commitment work system’s practices, since those support flexible operations, fast communication and problem-solving. The „quality” of the shift and hence the application of these work practices (number of practices, their embeddeness, employee involvement) highly depends on manufacturing strategy and lean maturity. (2) The concept of stages of manufacturing strategy (Wheelwright and Hayes, 1985) analyzes the role of the manufacturing function in the business strategy. Lean production is compatible with the „command and control” approach of the third stage of manufacturing strategy. These lean producers are cost-driven, they have the traditional approach of employees and apply new work organization practices to a less extent. However, the implementation of lean production may drive these companies to the fourth stage. The fourth stage of manufacturing strategy is based on employee involvement, problem-solving and learning. This stage is in full accordance with the „respect for people” pillar of lean production. (3) Lean maturity (Hines et al., 2004) shows the path how lean management deepens and expands within an organization. During the lean journey, companies progress from the tool-based approach to the complex lean value system. The technical knowledge of lean becomes more and more comprehensive and it points out the crucial importance of knowledge conversion capabilities (intrapersonal or even how to build knowledge into structures, processes). Work organization practices constantly appear with the progress, but the review of the traditional approach of employees is only essential at the most advanced stage, when an organization becomes lean learning organization.

Bizonytalanság, stratégia és teljesítmény – Kvalitatív kutatás innovatív kis- és középvállalatok vezetői körében (Uncertainty, strategy and performance – Qualitative research in innovative SMEs)

A szerző kvalitatív kutatási módszerekkel vizsgálja a kis- és középvállalatok (kkv-k) innovatív tevékenységeinek korlátait és lehetőségeit. A vizsgálat tárgyai (legalább) Magyarország szintjén új terméket vagy szolgáltatást nyújtó kkv-k, melyek határozott növekedési szándékkal rendelkeznek. Az eredmények egységes vizsgálati keretben, 41 vezető véleménye alapján születtek meg, három területre fókuszálva: (1) a környezeti bizonytalanság megítélése, (2) a szervezet követett stratégiája, kettős képessége, kiaknázó és felderítő tevékenysége, és (3) a versenyképes teljesítménycélok, konfigurációk. A cikk a kutatás lépéseit részletesen bemutatja, fontos eredményének tekinthető, hogy rámutat arra, hogy a kutatási és fejlesztési, valamint az innovatív tevékenységek legfontosabb gátja leginkább a vezetési és szervezési képességek és a stratégiai gondolkodás hiányára vezethető vissza a kis- és középvállalkozásokban. ______ The author conducted a qualitative research on the innovation potential of small and medium size enterprises (SMEs). SMEs with new products and services and with growth orientation are in the focus of the research. The standardized research design is based on 41 owner managers’ responses. It is focusing on 3 main areas: (1) environmental uncertainty, (2) the strategy followed by the organization, its ambidextrous capability, exploitative and explorative behavior, and (3) competitive performance and configurations. The paper describes a qualitative research design in detail. The main finding of the research is that the lack of managerial skills and strategic thinking inhibit SMEs to conduct innovation as well as to engage in research and development activities.

Innovációs kalandozások az elmélettől a stratégiáig = Innovation adventuring from theory to strategy

A cikk célja, hogy közelebb vigye az olvasót az innováció és az innovációmenedzsment kérdésköréhez. A tanulmány az innováció témakörének feldolgozását a vállalatelméleti alapoktól kezdi, majd konkrét stratégiai megfontolásokig jut el a cikk végére. A tanulmány széles körű hazai és nemzetközi szakirodalom alapján tárja fel az innováció vállalatelméleti gyökereit. A felhasznált irodalom nem ragad meg elméleti szinten, hiszen a tanulmány lefordítja ezeket az elméleti koncepciókat valós, gyakorlatorientált üzleti nyelvre. Célja, hogy a nagyvilágban szétszórt elméleteket letisztítsa, és a modern kori menedzsmentelvekkel szintetizálja. A cikk az innovációt a vállalati értékteremtés szemszögéből vizsgálja. Megállapítja, hogy az innováció számos vállalatelmélet tanait integrálja egybe, aminek következtében a stratégiai implikációk is széles spektrumon mozoghatnak. Ahogy az innováció változást indukál a szervezetben, úgy bukkannak fel komplex optimalizálási dilemmák, amelyek a turbulens gazdasági környezetben, a rövidülő reakcióidők miatt, egyre nagyobb kihívást okoznak a menedzserek számára. A cikk ezeket a dilemmákat mutatja be vitaindító attitűddel, valamint az elmélet és a gyakorlat szintetizálásával. ____ The aim of the article is to bring the reader closer to the topic of innovation management through several company theories and strategic implications. This study is based on a wide range of international literature which is interpreted in a practice oriented way. This article is summarizing the sporadic information on innovation as well as makes an effort on synthesizing this knowledge. The aspect of observation is mainly based on corporate value creation. As innovation causes changes into the organization company leaders have to face complex economic optimization questions. These management dilemmas are not easy to solve in this turbulent business environment. This article tries to highlight these strategic level issues around innovation management by synthesizing theoretical knowledge with business implications.

An Analysis of a Small Favela-Based Youth Organization

This research identifies the value of a community-run NGO (nongovermental organization) in its work to advocate for a more positive image of Rio’s favelas (urban slums). Basic interpretive inquiry is used to analyze interviews with the principle spokesperson for the organization. Recommendations for further research are made.

Essays on Energy Economics and Industrial Organization

The dissertation consists of three chapters related to the low-price guarantee marketing strategy and energy efficiency analysis. The low-price guarantee is a marketing strategy in which firms promise to charge consumers the lowest price among their competitors. Chapter 1 addresses the research question "Does a Low-Price Guarantee Induce Lower Prices'' by looking into the retail gasoline industry in Quebec where there was a major branded firm which started a low-price guarantee back in 1996. Chapter 2 does a consumer welfare analysis of low-price guarantees to drive police indications and offers a new explanation of the firms' incentives to adopt a low-price guarantee. Chapter 3 develops the energy performance indicators (EPIs) to measure energy efficiency of the manufacturing plants in pulp, paper and paperboard industry.

Chapter 1 revisits the traditional view that a low-price guarantee results in higher prices by facilitating collusion. Using accurate market definitions and station-level data from the retail gasoline industry in Quebec, I conducted a descriptive analysis based on stations and price zones to compare the price and sales movement before and after the guarantee was adopted. I find that, contrary to the traditional view, the stores that offered the guarantee significantly decreased their prices and increased their sales. I also build a difference-in-difference model to quantify the decrease in posted price of the stores that offered the guarantee to be 0.7 cents per liter. While this change is significant, I do not find the response in comeptitors' prices to be significant. The sales of the stores that offered the guarantee increased significantly while the competitors' sales decreased significantly. However, the significance vanishes if I use the station clustered standard errors. Comparing my observations and the predictions of different theories of modeling low-price guarantees, I conclude the empirical evidence here supports that the low-price guarantee is a simple commitment device and induces lower prices.

Chapter 2 conducts a consumer welfare analysis of low-price guarantees to address the antitrust concerns and potential regulations from the government; explains the firms' potential incentives to adopt a low-price guarantee. Using station-level data from the retail gasoline industry in Quebec, I estimated consumers' demand of gasoline by a structural model with spatial competition incorporating the low-price guarantee as a commitment device, which allows firms to pre-commit to charge the lowest price among their competitors. The counterfactual analysis under the Bertrand competition setting shows that the stores that offered the guarantee attracted a lot more consumers and decreased their posted price by 0.6 cents per liter. Although the matching stores suffered a decrease in profits from gasoline sales, they are incentivized to adopt the low-price guarantee to attract more consumers to visit the store likely increasing profits at attached convenience stores. Firms have strong incentives to adopt a low-price guarantee on the product that their consumers are most price-sensitive about, while earning a profit from the products that are not covered in the guarantee. I estimate that consumers earn about 0.3% more surplus when the low-price guarantee is in place, which suggests that the authorities should not be concerned and regulate low-price guarantees. In Appendix B, I also propose an empirical model to look into how low-price guarantees would change consumer search behavior and whether consumer search plays an important role in estimating consumer surplus accurately.

Chapter 3, joint with Gale Boyd, describes work with the pulp, paper, and paperboard (PP&PB) industry to provide a plant-level indicator of energy efficiency for facilities that produce various types of paper products in the United States. Organizations that implement strategic energy management programs undertake a set of activities that, if carried out properly, have the potential to deliver sustained energy savings. Energy performance benchmarking is a key activity of strategic energy management and one way to enable companies to set energy efficiency targets for manufacturing facilities. The opportunity to assess plant energy performance through a comparison with similar plants in its industry is a highly desirable and strategic method of benchmarking for industrial energy managers. However, access to energy performance data for conducting industry benchmarking is usually unavailable to most industrial energy managers. The U.S. Environmental Protection Agency (EPA), through its ENERGY STAR program, seeks to overcome this barrier through the development of manufacturing sector-based plant energy performance indicators (EPIs) that encourage U.S. industries to use energy more efficiently. In the development of the energy performance indicator tools, consideration is given to the role that performance-based indicators play in motivating change; the steps necessary for indicator development, from interacting with an industry in securing adequate data for the indicator; and actual application and use of an indicator when complete. How indicators are employed in EPA’s efforts to encourage industries to voluntarily improve their use of energy is discussed as well. The chapter describes the data and statistical methods used to construct the EPI for plants within selected segments of the pulp, paper, and paperboard industry: specifically pulp mills and integrated paper & paperboard mills. The individual equations are presented, as are the instructions for using those equations as implemented in an associated Microsoft Excel-based spreadsheet tool.

Task-based approach used on surfaces sampling strategy definition: the case of antineoplastic occupational exposure

Task-based approach implicates identifying all the tasks developed in each workplace aiming to refine the exposure characterization. The starting point of this approach is the recognition that only through a more detailed and comprehensive understanding of tasks is possible to understand, in more detail, the exposure scenario. In addition allows also the most suitable risk management measures identification. This approach can be also used when there is a need of identifying the workplace surfaces for sampling chemicals that have the dermal exposure route as the most important. In this case is possible to identify, through detail observation of tasks performance, the surfaces that involves higher contact (frequency) by the workers and can be contaminated. Identify the surfaces to sample when performing occupational exposure assessment to antineoplasic agents. Surfaces selection done based on the task-based approach.

Justification the strategy of enterprise development: PJSC Elektrotermometriya: case study

The research is orientated to the actual issues of strategic management of industrial enterprises. The theoretical aspects of strategic management are generalized, its role is certain in organization development, methods and processes of strategic management are investigational. In this context the main objective of study is based on the strategic analysis of PJSC «Elektrotermometriya», formation ways to improve the strategic management of the company with regard to the readiness of the company to strategic changes and conducting of developments and recommendations for improvement activity of the enterprise. To answer to the main objective it was conducted the strategic analysis of activity of PJSC «Elektrotermometriya». The results proved the basic strategy to achieve the strategic goal of PJSC «Elektrotermometriya». According to the life cycle, and based on the current conditions of its functioning, is appropriate to use the strategy of gradual growth. Forecast implementing strategies defined by the optimistic, probable and pessimistic forecasts. According to the pessimistic forecast the company should use a strategy of stabilization, while to the optimistic and the most likely scenario - moderate growth strategy. Thus to achieve the main strategic goals according to each scenario PJSC «Elektrotermometriya» should use set of functional strategies and define the business strategy.

Development of an innovative non rule-based energy management strategy for a Hybrid Electric Vehicle, structured for predictive driving controls based on external information knowledge

Recently, the interest of the automotive market for hybrid vehicles has increased due to the more restrictive pollutants emissions legislation and to the necessity of decreasing the fossil fuel consumption, since such solution allows a consistent improvement of the vehicle global efficiency. The term hybridization regards the energy flow in the powertrain of a vehicle: a standard vehicle has, usually, only one energy source and one energy tank; instead, a hybrid vehicle has at least two energy sources. In most cases, the prime mover is an internal combustion engine (ICE) while the auxiliary energy source can be mechanical, electrical, pneumatic or hydraulic. It is expected from the control unit of a hybrid vehicle the use of the ICE in high efficiency working zones and to shut it down when it is more convenient, while using the EMG at partial loads and as a fast torque response during transients. However, the battery state of charge may represent a limitation for such a strategy. That’s the reason why, in most cases, energy management strategies are based on the State Of Charge, or SOC, control. Several studies have been conducted on this topic and many different approaches have been illustrated. The purpose of this dissertation is to develop an online (usable on-board) control strategy in which the operating modes are defined using an instantaneous optimization method that minimizes the equivalent fuel consumption of a hybrid electric vehicle. The equivalent fuel consumption is calculated by taking into account the total energy used by the hybrid powertrain during the propulsion phases. The first section presents the hybrid vehicles characteristics. The second chapter describes the global model, with a particular focus on the energy management strategies usable for the supervisory control of such a powertrain. The third chapter shows the performance of the implemented controller on a NEDC cycle compared with the one obtained with the original control strategy.

Coaching or gaming? Implications of strategy choice for home based stroke rehabilitation

Background: The enduring aging of the world population and prospective increase of age-related chronic diseases urge the implementation of new models for healthcare delivery. One strategy relies on ICT (Information and Communications Technology) home-based solutions allowing clients to pursue their treatments without institutionalization. Stroke survivors are a particular population that could strongly benefit from such solutions, but is not yet clear what the best approach is for bringing forth an adequate and sustainable usage of home-based rehabilitation systems. Here we explore two possible approaches: coaching and gaming. Methods: We performed trials with 20 healthy participants and 5 chronic stroke survivors to study and compare execution of an elbow flexion and extension task when performed within a coaching mode that provides encouragement or within a gaming mode. For each mode we analyzed compliance, arm movement kinematics and task scores. In addition, we assessed the usability and acceptance of the proposed modes through a customized self-report questionnaire. Results: In the healthy participants sample, 13/20 preferred the gaming mode and rated it as being significantly more fun (p < .05), but the feedback delivered by the coaching mode was subjectively perceived as being more useful (p < .01). In addition, the activity level (number of repetitions and total movement of the end effector) was significantly higher (p <.001) during coaching. However, the quality of movements was superior in gaming with a trend towards shorter movement duration (p=.074), significantly shorter travel distance (p <.001), higher movement efficiency (p <.001) and higher performance scores (p <.001). Stroke survivors also showed a trend towards higher activity levels in coaching, but with more movement quality during gaming. Finally, both training modes showed overall high acceptance. Conclusions: Gaming led to higher enjoyment and increased quality in movement execution in healthy participants. However, we observed that game mechanics strongly determined user behavior and limited activity levels. In contrast, coaching generated higher activity levels. Hence, the purpose of treatment and profile of end-users has to be considered when deciding on the most adequate approach for home based stroke rehabilitation.

A multiagent based strategy for detecting attacks in databases in a distributed mode

This paper presents a distributed hierarchical multiagent architecture for detecting SQL injection attacks against databases. It uses a novel strategy, which is supported by a Case-Based Reasoning mechanism, which provides to the classifier agents with a great capacity of learning and adaptation to face this type of attack. The architecture combines strategies of intrusion detection systems such as misuse detection and anomaly detection. It has been tested and the results are presented in this paper.

Iowa Nutrient Reduction Strategy : a science and technology-based framework to assess and reduce nutrients to Iowa waters and the Gulf of Mexico (2016)

On November 19, 2012, Iowa Gov. Terry Branstad, Iowa Secretary of Agriculture Bill Northey, Director Chuck Gipp from the Iowa Department of Natural Resources and Dr. John Lawrence of Iowa State University announced the release of the Iowa Nutrient Reduction Strategy for public comment. A two-month public comment period and several informational meetings allowed the public to provide feedback on the draft strategy. Updates and improvements were made to the draft based on the public comments. The final version of the strategy was released May 29, 2013. The Iowa Nutrient Reduction Strategy is a science and technology-based approach to assess and reduce nutrients delivered to Iowa waterways and the Gulf of Mexico. The strategy outlines voluntary efforts to reduce nutrients in surface water from both point sources, such as wastewater treatment plants and industrial facilities, and nonpoint sources, including farm fields and urban areas, in a scientific, reasonable and cost effective manner. The development of the strategy reflects more than two years of work led by the Iowa Department of Agriculture and Land Stewardship, Iowa Department of Natural Resources and Iowa State University. The scientific assessment to evaluate and model the effects of practices was developed through the efforts of 23 individuals representing five agencies or organizations, including scientists from ISU, IDALS, DNR, USDA Agricultural Research Service and USDA Natural Resources Conservation Service. The strategy was developed in response to the 2008 Gulf Hypoxia Action Plan that calls for the 12 states along the Mississippi River to develop strategies to reduce nutrient loading to the Gulf of Mexico. The Iowa strategy follows the recommended framework provided by EPA in 2011 and is only the second state to complete a statewide nutrient reduction strategy. This strategy is the beginning. Operational plans are being developed and work is underway. This is a dynamic document that will evolve over time, and is a key step towards improving Iowa’s water quality. The impetus for this report comes from the Water Resources Coordination Council (WRCC) which states in its 2014‐15 Annual Report “Efforts are underway to improve understanding of the multiple nutrient monitoring efforts that may be available and can be compared to the nutrient WQ monitoring framework to identify opportunities and potential data gaps to better coordinate and prioritize future nutrient monitoring efforts.” This report is the culmination of those efforts.