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Статті в журналах з теми "Supply networks from distribution point of view"
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Zelewski, Stephan, and Malte L. Peters. "Fair Distribution of Efficiency Gains in Supply Networks from a Cooperative Game Theory Point of View." International Journal of Information Systems and Supply Chain Management 3, no. 2 (April 2010): 1–24. http://dx.doi.org/10.4018/jisscm.2010040101.
Повний текст джерелаАнотація:
In this paper, the authors address the distribution of efficiency gains among partially autonomous supply network actors in a manner they will accept as fair and as an incentive to cooperation. The problem is economically significant because it requires substantiating efficiency gains in an understandable manner. Moreover, supply networks suffer from a conflict potential because the partially autonomous actors seek to maximize their own shares of the efficiency gain. The method applied appropriates a model from cooperative game theory involving the t-value. The special nature of the t-value ensures that it seems rational to the actors to cooperate in the supply network. The proposed method for the distribution problem offers a fair distribution of efficiency gains in the supply network and ensures that the distribution results can be communicated easily.
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Szczepański, Emilian, Ilona Jacyna-Gołda, and Jakub Murawski. "GENETIC ALGORITHMS BASED APPROACH FOR TRANSHIPMENT HUB LOCATION IN URBAN AREAS." Archives of Transport 31, no. 3 (September 30, 2014): 73–82. http://dx.doi.org/10.5604/08669546.1146989.
Повний текст джерелаАнотація:
Points of distribution, sales or service are important elements of the supply chain. These are the final elements which are responsible for proper functioning of the whole cargo distribution process. Proper location of these points in the transport network is essential to ensure the effectiveness and reliability of the supply chain. The location of these points is very important also from the consumers point of view. In this paper developed method of points location was present on the example of urban transport network. The developed approach is based on the Vehicle Routing Problem in the multistage distribution systems. The proposed method uses a genetic algorithm. Article also presents a mathematical model of delivery cost as a criterion func
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Pawar, Mukund M., and Nitin P. Sonaje. "Converting Traditional Water Supply Network Into 24x7, using Water GEMS to Optimize Design." International Journal of Recent Technology and Engineering 10, no. 1 (May 30, 2021): 280–84. http://dx.doi.org/10.35940/ijrte.a5937.0510121.
Повний текст джерелаАнотація:
Water is all-natural driving force. Entire world struggles to preserve it. Given that India is among the top 12 water poor countries, water wastage is a critical issue for us. India's population is increasing day by day and thus the demand for water is continuously increasing. This growing demand can be met through an efficient water distribution network which can be designed using modern hydraulic software such as Water GEMS. Using the Water GEMS software Pandharpur city is selected to convert existing water supply system into 24 * 7 continuous water supply systems. The largest investment is the pipes used in the water distribution system. The design, modeling and optimization of pipes in water supply system from an economic point of view are very important. Therefore optimal pipe network design for converting existing network into 24x7 water supply system networks is carried out in this paper to reduce the cost using WaterGEM software. Study of the existing water supply network system for one zone (Ambika Nagar Zone10) is initially carried out from the Pandharpur area. The effect on demand, head loss gradient, and pressure development of the forecasted population is studied. In addition, cost optimization of the pipe network for the proposed 24x7 water supply system is carried out using a genetic algorithms Darwin optimization approach.
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Frankowska, Marzena, Andrzej Rzeczycki, Mariusz Sowa, and Wojciech Drożdż. "Functional Model of Power Grid Stabilization in the Green Hydrogen Supply Chain System—Conceptual Assumptions." Energies 16, no. 1 (December 23, 2022): 154. http://dx.doi.org/10.3390/en16010154.
Повний текст джерелаАнотація:
Green hydrogen supply chain includes supply sources, production, and distribution of hydrogen produced from renewable energy sources (RES). It is a promising scientific and application area, as it is related to the problem of instability of power grids supplied with RES. The article presents the conceptual assumptions of the research on the design of a functional multi-criteria model of the stabilization model architecture of energy distribution networks based on a hydrogen energy buffer, taking into account the applicable use of hydrogen. The aim of the research was to identify the variables contributing to the stabilization of the operation of distribution networks. The method used to obtain this result was a systematic review of the literature using the technique of in-depth analysis of full-text articles and expert consultations. The concept of a functional model was described as a matrix in two dimensions in which the identified variables were embedded. The first dimension covers the phases of the supply chain: procurement and production along with storage and distribution. The second dimension divides the separate factors into technical, economic, and logistic. The research was conducted in the context of system optimization from the point of view of the operator of the energy distribution system. As a result of the research, several benefits resulting from stabilization using a hydrogen buffer were identified. Furthermore, the model may be used in designing solutions stabilizing the operation of power grids in which there are surpluses of electricity produced from RES. Due to the applied multidimensional approach, the developed model is recommended for use, as it enables the design of solutions in a systemic manner. Due to the growing level of energy obtained from renewable energy sources, the issue of stabilizing the energy network is becoming increasingly important for energy network distributors.
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Shoji, Gaku, and Ayumi Toyota. "Function of Emergency Road Networks During the Post-Earthquake Process of Lifeline Systems Restoration." Journal of Disaster Research 7, no. 2 (February 1, 2012): 173–83. http://dx.doi.org/10.20965/jdr.2012.p0173.
Повний текст джерелаАнотація:
This paper aims to present a framework for evaluating the functionality of emergency road networks after an earthquake from the perspective of local assistance during the process of restoring lifeline systems, such as electric power supply systems, gas supply systems and telecommunication networks. For the analysis, an earthquake of M7.3 in the Tokyo metropolitan area is anticipated, and the following types of local assistance between the related bases and the lifeline systems in the Kanto area are assumed. We employ four indices to quantify the physical and functional states of emergency road networks to be used during the post-earthquake restoration process: distance exposed by seismic intensity spatial distribution and distance exposed by PL value spatial distribution, the indices of which denote the physical state of the road networks as a result of ground motions and liquefaction, distance weighted by traffic congestion level, and distance weighted by averaged traveling time during the congestion, the indices of which denote the functional state of the road networks before being subjected to the above-mentioned seismic disturbances. By using the indices to evaluate the function of the networks from the point of view of efficiency in terms of gathering human resources and restoration materials, we can determine the most effective emergency road networks and related bases to provide local assistance to lifeline systems.
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Wang, Wen Xing, and Guang Zheng Wang. "Research and Design of Multigrounded in Micro-Grid Power Supply with Analysis of Electricity Energy." Advanced Materials Research 648 (January 2013): 210–13. http://dx.doi.org/10.4028/www.scientific.net/amr.648.210.
Повний текст джерелаАнотація:
After a large number of distributed electricity energy has been accessed to network, the system structure and operating characteristics of the distribution network will be greatly changed. The multigrounding of the micro-grid system was discussed from the provisions of the relevant electrical standards and the view of practical point. It is clear that PE wire is the repeated grounding instead of N repeated grounding in the TN system of micro-grid, and multigrounding problems that should be attention were described in TN-S and TT systems of micro-grid.
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Borrás-Talavera, María Dolores, Juan Carlos Bravo, and César Álvarez-Arroyo. "Instantaneous Disturbance Index for Power Distribution Networks." Sensors 21, no. 4 (February 14, 2021): 1348. http://dx.doi.org/10.3390/s21041348.
Повний текст джерелаАнотація:
The stability of power systems is very sensitive to voltage or current variations caused by the discontinuous supply of renewable power feeders. Moreover, the impact of these anomalies varies depending on the sensitivity/resilience of customer and transmission system equipment to those deviations. From any of these points of view, an instantaneous characterization of power quality (PQ) aspects becomes an important task. For this purpose, a wavelet-based power quality indices (PQIs) are introduced in this paper. An instantaneous disturbance index (ITD(t)) and a Global Disturbance Ratio index (GDR) are defined to integrally reflect the PQ level in Power Distribution Networks (PDN) under steady-state and/or transient conditions. With only these two indices it is possible to quantify the effects of non-stationary disturbances with high resolution and precision. These PQIs offer an advantage over other similar because of the suitable choice of mother wavelet function that permits to minimize leakage errors between wavelet levels. The wavelet-based algorithms which give rise to these PQIs can be implemented in smart sensors and used for monitoring purposes in PDN. The applicability of the proposed indices is validated by using a real-time experimental platform. In this emulated power system, signals are generated and real-time data are analyzed by a specifically designed software. The effectiveness of this method of detection and identification of disturbances has been proven by comparing the proposed PQIs with classical indices. The results confirm that the proposed method efficiently extracts the characteristics of each component from the multi-event test signals and thus clearly indicates the combined effect of these events through an accurate estimation of the PQIs.
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De Felice, Fabio, and Antonella Petrillo. "A Strategic Multicriteria Decision Support System to Assess the Best Supply Chain Distribution Strategy and Characterize the Bullwhip Effect." International Journal of Information Systems and Supply Chain Management 6, no. 4 (October 2013): 61–76. http://dx.doi.org/10.4018/ijisscm.2013100104.
Повний текст джерелаАнотація:
The attention on optimal management of production systems has increased, thus the control of production with local control of the coordination of an entire chain of production and distribution (Supply Chain Management). The aim of this work is to analyze some issues relating to new types of production realities based on the Supply Chain, to show the multiple causes of the change in demand along a Supply Chain, the reasons that cause the Bullwhip Effect and the techniques to improve it. From this point of view the authors have developed a strategic multicriteria decision support system based on the Analityc Network Process with which the authors can analyze the criticality throughout the supply chain process. Definitively this paper introduces a conceptual framework for evaluating different supply chain structures in the context of Bullwhip Effect. The authors also illustrate the applicability of the resulting framework through a specific model applied in an automotive industry.
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Valery, Lukinskiy, and Lukinskiy Vladislav. "Designing the Analytical Base for Optimal Allocation of Stocks in Supply Chains." Transport and Telecommunication Journal 19, no. 4 (December 1, 2018): 346–55. http://dx.doi.org/10.2478/ttj-2018-0029.
Повний текст джерелаАнотація:
Abstract The carried out studies show that from the point of view of the issue of efficiency increase of logistical systems, there are several key aspects. Firstly, choice of methods for managing the triad of logistics functions ‘inventory management - warehousing – transportation’, where the inventory management issues are considered as the most relevant ones. Secondly, there is recognized the need to move the studies of multi-level systems within the framework of the concept of supply chain management. Nowadays, supply chains, which are represented by the distribution system, are widespread in practice. The most common of them are two-level ones with a central supplier at the second level and a certain number of companies at the first level; and multi-level systems of the distribution configuration network in which multi-nomenclature stocks are located. The article is devoted to the design and enhancement of analytical platform for inventory management in such distribution systems.
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Kyzym, Mykola O., Tetiana I. Salashenko, and Yevhen I. Kotliarov. "Development of Heat Energy Markets: Experience of European Countries and Conclusions for Ukraine." Business Inform 11, no. 538 (2022): 64–75. http://dx.doi.org/10.32983/2222-4459-2022-11-64-75.
Повний текст джерелаАнотація:
The purpose of the article is to study the European experience of the functioning of heat energy markets, identify the components of their deregulation, and develop proposals for the formation of regional heat markets in Ukraine. The article stipulates that currently there is no trans-European legislation on the formation of heat energy markets, there are only certain provisions that relate to its production, consumption and accounting. From a theoretical point of view, there are three types of competition in the heat energy markets: between heat supply sources; between producers of centralized heat; between companies for assets. The analyzed experience in the development of heat energy markets in three European countries testifies to the fundamental differences in its structure. Denmark’s heat energy markets are government-regulated, where there is a partial distinction between the functions of production, transportation, and distribution of heat; pricing is carried out on a regulatory basis of non-profit; there are no transparent conditions for access to the network, and the consumer has limited opportunities to disconnect from the system. In Sweden, competition is open at the wholesale level between heat producers; the functions of production and supply are demarcated, and the distribution and supply functions are combined; the retail heat market is self-regulating, which implies the need to coordinate heat prices between suppliers and consumers who, in case of disagreement, have the opportunity to refuse centralized heat supply. Lithuanian heat energy markets are open to wholesale competition and operate in the forward segment, while at the retail level they are regulated, where the transmission from production and supply has been unbundled; regulatory access to heating networks for independent producers has been introduced, and consumers have the right to refuse centralized heat supply. The highlighted features allowed to provide proposals for the formation of heat energy markets in Ukraine, including: the development of competition between heat producers; delimitation of the functions of production, transmission and distribution; formation of its forward, spot and balancing segments; introduction of auctions with the declared pricing method under the pressure of regulatory price restrictions, which are established on the basis of business standards according to the benchmarking system.
Дисертації з теми "Supply networks from distribution point of view"
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Tyagi, Arjun. "Performance improvement of modern distribution systems." Thesis, 2018. http://localhost:8080/xmlui/handle/12345678/7625.
Повний текст джерелаЧастини книг з теми "Supply networks from distribution point of view"
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Zelewski, Stephan. "Fair Distribution of Cooperation Gains in Supply Chains: A Justification Program from an Economic Point of View." In Contributions to Management Science, 211–34. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-61603-2_10.
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Bányai, Ágota. "Supply Chain: A Modeling-Based Approach for Cyber-Physical Systems." In Supply Chain - Recent Advances and New Perspectives in the Industry 4.0 Era [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.105527.
Повний текст джерелаАнотація:
Within the frame of this chapter, the author focuses on the distribution processes of green supply chain solutions and describes a potential mathematical model, taking environmental aspects into consideration. The first part of the chapter includes a systematic literature review. Based on the identified research gap, a new mathematical model is described, which makes it possible to describe last-mile logistics processes from an environmental point of view. The functional model of the distribution system includes the potential of Industry 4.0 technologies, which makes it possible to gather real-time information from the distribution process and use real-time status information for a sophisticated design and operation. The mathematical model of this approach defines an NP-hard optimization problem; therefore, heuristic optimization algorithm is supposed to solve the design and operation tasks of the green distribution problem. As the computational results show, cyber-physical systems increase the performance of green supply chain solutions and have a great impact on operational cost. As the numerical example shows, the integrated approach resulted in a 5.3% cost reduction in transportation operations.
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Bányai, Tamás, and Mohammad Zaher Akkad. "The Impact of Industry 4.0 on the Future of Green Supply Chain." In Green Supply Chain [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.98366.
Повний текст джерелаАнотація:
The fourth industrial revolution offers new technologies to transform conventional supply chain solutions into cyber-physical supply chain ones. This transformation makes it possible to increase the efficiency, availability, quality, and cost-efficiency of the value-making chain, while the energy consumption and the GHG emission can be decreased. Within the frame of this chapter, the authors introduce the most important Industry 4.0 technologies and Internet of Things tools and demonstrate their potentials to update supply chain operations. This update of conventional operations can lead to greener and more sustainable purchasing, production, and distribution processes. The successful future of the green supply chain is based on a wide range of factors, like production management, logistics management, societal and regulatory environment. However, the Industry 4.0 technologies are expected to strongly influence the whole supply chain performance positively. This chapter aims to explore the potentials of Industry 4.0 technologies and the transformation of conventional supply chain solutions into cyber-physical systems, especially from a municipal waste collection point of view. The research findings can provide useful insights for supply chain experts, manufacturing, and service companies.
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Anttiroiko, Ari-Veikko, and Roger W. Caves. "Urban Planning 3.0." In Mobile Computing and Wireless Networks, 439–60. IGI Global, 2016. http://dx.doi.org/10.4018/978-1-4666-8751-6.ch020.
Повний текст джерелаАнотація:
This chapter addresses the challenges that changing technologies pose to urban planning. Urban planning continues to be influenced by an emerging creativity and knowledge-sharing culture that has an inherent connection to digital transformation. Technology certainly plays an important role in the production of content and its distribution. Such a transformation is giving urban planning a new look, which is depicted in the concepts of Urban Planning 2.0 and Urban Planning 3.0. In this chapter, this paradigm shift is explained and illustrated with a special view to identifying the ways these second and third generations of the Web affect urban planning. There is a plethora of pilot projects and new practices in Urban Planning 2.0, even if experiences as a whole are so few and far between, which makes it difficult to assess both the best practices in this field and the long-term impacts of their application. Recent developments associated with the applications of Web 3.0 and related technology trends in urban planning, which are designed to bring intelligence into planning, have hardly seen daylight due to both technological and socio-technical challenges associated with them. In brief, in the case of Web 2.0, we know on the basis of our initial experiences by and large how it may support urban planning; however, in the case of Web 3.0, technological uncertainties and systemic dimension of related applications make the concept more ambiguous and thus more challenging to assess what the true potential of this emerging Web trend is from the point of view of urban planning.
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Ortloff, Charles R. "Hydraulic Engineering and Water Management Strategies ofAncient Societies." In Water Engineering in the Ancient World. Oxford University Press, 2009. http://dx.doi.org/10.1093/oso/9780199239092.003.0007.
Повний текст джерелаАнотація:
Societies of widely different social, economic, political, religious, and technical innovation characteristics in opposing world hemispheres developed urban and rural population centres with water and agricultural systems to maintain stable economies and expanding populations. Despite vast historical, cultural, and world view differences between these societies, one common thread united them: the necessity for mastery of engineering skills to provide water for cities and agricultural systems. Although it may be thought that the technical basis to support water engineering practice is accompanied with pre-scientific concepts, many recent discoveries reveal the contrary: sophistication in the concept, design, and execution of water supply and distribution systems indicating knowledge of hydraulic principles beyond the scant hydraulics literature that survived the centuries. In the absence of ancient treatises on hydraulics practices, archaeological analysis of hydraulics works coupled with modern analysis methods provides a way to understand their technological accomplishments through ‘reverse engineering’ methodologies involving computer modelling techniques. Thus computer methodologies play a role to uncover the design intent, functionality, and operation of ancient water systems to provide insight into ancient engineering practices and their theoretical/empirical basis. In South American archaeology, the large variation in ecological conditions and landscape barriers provided the stage for the rise of civilizations and largely determined their agricultural practices. As an example, the Chimú civilization (800–1480 CE) occupied Peruvian coastal regions extending 500 km from the southern Chillon Valley to the northern Lambeyeque Valley. The desert coastal zone extends only a few kilometres inland from the Pacific Ocean before being bounded by the Cordillera Negra mountain chain. Agriculture was possible in coastal alluvial valleys through networks of canal systems originating from intermittent seasonal rivers. The temperature near the equator is near constant throughout the year while coastal rainfall averages about 2mm/year; occasional massive El Niño events which can deposit up to 150cm of rainfall in a few days occasionally break this pattern and cause extensive flooding and Weld erosion. Clearly, hydraulic practices related to the control of limited (and sometime excessive) water resources were vital for survival. Defensive measures to protect fill aqueduct structures against excessive El Niño rainfall and flooding events are expected to appear in the technology base as flood control was vital to sustainability.
Тези доповідей конференцій з теми "Supply networks from distribution point of view"
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Lvov, Aleksandr, I. Priedite-Razgale, J. Rozenkrons, and V. Kreslins. "Assessment of different power line types' life-time costs in distribution network from reliability point of view." In 2012 Electric Power Quality and Supply Reliability Conference (PQ). IEEE, 2012. http://dx.doi.org/10.1109/pq.2012.6256220.
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Kulkarni, Sukrut Shridhar, and Marliana Bt Mohammad. "Integrated Standpoint for Monetizing High CO2 Field with Deliberation of Technical Evaluation and Project Economics." In ADIPEC. SPE, 2022. http://dx.doi.org/10.2118/211342-ms.
Повний текст джерелаАнотація:
Abstract Monetization of high Carbon dioxide (CO2) field poses a major challenge for optimization either in terms of evacuation (long dedicated pipelines/system) or exotic offshore treatment for CO2 management in terms of CAPEX/OPEX. As the resilient field developer, it is significant to realize economic development of project feasibility is in the harmony with planned supply/demand balance, infrastructure requirement and value generation to the project. It is also noteworthy to comprehend that alignment is in place from appropriate field to intended customer. It's therefore imperious to the prudent operator to be further resilient, more agile, technologically stronger, and financially more robust dealing with the development options for upcoming sour fields. This paper deals with comprehensive analysis of two options for high CO2 field development to arrive at optimized way forward with technical evaluation and finest project economics. What if scenarios were appraised along with project economics to Profit to Investment Ratio (PIR), Net Present Value (NPV) and Internal Rate of Return (IRR) to determine the best option for the project monetization. Among criteria considered were the cost phasing involved (CAPEX/OPEX), the potential first hydrocarbon date and related field sequence to overall gas distribution network infrastructure. Numerous assessments for strategic alignment were accomplished by leveraging on design, development and implementation of integrated network modeling that was commenced in syndication with appropriate stakeholders such as strategic, operational, projects and commercial. The developed hydraulic model based on first principle was intended that could perform the what-if scenarios in terms of technical aspect by identifying the system ullages, contaminant mapping provision, and pain points identification. Appropriate thermodynamic environment along with flow correlations & engineering details were assembled to represent situ conditions for infrastructure containing around 100+ feeders, ~4000 kms of pipeline with multiple demand centers in place. The model was validated with plant information (data) as part of history matching and validated model was deployed for robust prediction. Detailed diagnostic was performed to recognize the implications on the network for option of long pipeline selection against exotic treatment for contaminants. Project economics were more representative as model could increase the accuracy level by appending the exact sizing of facilities considering holistic view. Multiple tie-in opportunity was explored as best fit considering the optimization in CAPEX/OPEX based on system requirement. Amendment in the control philosophies, clustering of high contaminant feeders was also proposed in benefit of new field viability unlike current practice for going end to end new facility with high capex. The technical simulation is supported by the project's economics of the scenarios. The CAPEX phasing of the best fit option yields a higher Profit to Investment Ratio (PIR) compared to once off spent. Impact of each criterion to the chosen profitability indicators was analyzed and compared to business aspiration to ensure the recommendation corresponds with inclusive overview. With this approach the visibility was extended to overall network level to frame the big picture to the project advantage and the organization. Comprehensive technical and commercial analysis in wide spectrum of end-to-end gas business was the game changer in optimizing the project economics for field development. The Final Investment Decision (FID) could be achieved with lower levels of risk and uncertainty by leveraging on the data based on technical deliberation via network modelling and its impact on overall project economics.
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Nakano, Takashi, Yuichiro Waki, Yuki Sumi, Chihiro Yoshimine, and Teruaki Yamawaki. "Development of High Specific Load and Low Mechanical Loss Journal Bearing With Two Pads of Tilting Supported Type." In ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/gt2018-75593.
Повний текст джерелаАнотація:
The demand for improving the steam turbine economic efficiency is being expected for both GTCC and conventional power plants. MHPS suggests HP/IP/LP separate casing and one bearing/rotor (one bearing between two casings) type steam turbine to enhance the turbine efficiency and reduce the cost of construction. Separate casing is preferable for blade aerodynamic performance, and one bearing/rotor is effective to reduce turbine bearing mechanical losses and turbine length. From the view point to design this type of rotor shaft arrangement, the most important point is to apply bearing technologies to permit the higher specific load and lower mechanical loss as well as for better dynamic oil film characteristics. The new two pads tilting journal bearing has been developed, utilizing MHPS’s experience on traditional two pads bearing with direct lubrication. The bearing structure and design parameters are optimized and good static and dynamic performance are obtained. Further, as practical countermeasures for a sub-synchronous vibration, the oil supply nozzle efficiency is improved, while properly adjusting supply oil flow distribution. The 610 mm size bearing test was conducted in-house test facility. The limit of specific load was verified, the bearing loss has become less than target.
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Madžarević, Aleksandar. "Analysis and calculation of MMRS and primary gas distribution network in urban environment – case study Kučevo." In 35th International Congress on Process Industry. SMEITS, 2022. http://dx.doi.org/10.24094/ptk.022.067.
Повний текст джерелаАнотація:
The field of application of natural gas is very wide. As an energy source, it can be used for energy production in power plants, heating plants and cogeneration plants or for meeting various heat needs in industry and mass consumption. Gas can also be used as a raw material in the chemical and petrochemical industries, and during the last decades it has also been used in traffic as a propellant in SUS engines. From an environmental point of view, natural gas is the most acceptable source of energy compared to other fossil fuels. Due to its chemical composition, the combustion of natural gas emits significantly less carbon dioxide per unit of heat produced, there is no ash and no particulate emissions, and sulfur dioxide emissions are negligible. Natural gas is often called the "fuel of the 21st century" because, in addition to environmental advantages, it also has pronounced technical and economic advantages over other conventional fuels. From a technical and economic point of view, the advantages of using gas are low investment costs and price, high degree of utilization, reliability and flexibility of use, easier and safer storage compared to other fossil fuels. This fuel is available throughout the year, and its quality is standardized and guaranteed. Although the world's proven reserves are abundant, the rational management and use of natural gas is extremely important, given the fact that it is a non-renewable energy source. As it is a flammable and explosive mixture, careful handling and odorization of gas is a prerequisite for safe operation in all plants that use this type of fuel in their operational processes. The contribution of gas to increasing the greenhouse effect can also be singled out as a disadvantage. The aim of this paper is to find the optimal shape of the route of the primary distribution network of gas pipelines in the municipality of Kučevo, defining locations and positions of MMRS and MRS, adoption of supporting equipment for MMRS, pipe sizing based on norms and regulations for medium and high-pressure distribution networks. in supplying both current and future consumers.
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Sangi, R., R. Streblow, and Dirk Müller. "Dynamic Modeling, Simulation and Exergy Analysis of an Innovative Hydronic Heating System." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-63560.
Повний текст джерелаАнотація:
In this study, dynamic modeling and simulation of a decentralized hydronic heating system has been performed. The simulated space heating system is a model of an innovative heating system of an apartment with a boiler that supplies heat for eight radiators which are served by distribution pipes. Eight small pumps, located at the outlet of the radiators instead of a central circulation pump, work according to demand, and supply each radiator with hot water only when required. A PID controller regulates the rotational speed of the pumps and consequently the power of the radiators to maintain the room temperature at the set point. To evaluate the performance of such a heating system, a model of the entire energy chain from generation to distribution is needed. Therefore, in this work, detailed sub-models for the hydraulic system have been developed and coupled with the model of a building to make a general model for simulating the performance of the whole system. The analysis has been carried out by simulation of the system using the object-oriented programing language Modelica. Dymola, which is a multi-domain modeling and simulation tool, has been used as simulation environment. The Modelica Standard Library 3.2 and the Modelica libraries for building simulation such as BaseLib, Database, Building and HVAC components libraries have been applied to simulate the hydraulic and thermal behavior of the system. In the next step, the system has been analyzed form exergy point of view and the simulation results from the dynamic model have been presented in an exergetic framework.
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Kim, Jeong Hwan, Joong Hyo Choi, Sung Gun Park, Dong Kwon Lee, and Yeong Tae Oh. "Structural Development of LNG Fueled Large Container Ship." In ASME 2013 32nd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/omae2013-10634.
Повний текст джерелаАнотація:
There is a growing interest in the appearance of LNG fueled large commercial ship with rising oil price and stronger emission regulation of these days. Though small or middle size LNG fueled vessels have been already operated, the application of LNG fuel to large commercial vessels is now under developing in stage. LNG fueled propulsion system can be characterized by three differences than typical propulsion system. First one is 2-stroke dual fuel engine, second one is high pressure fuel supply system and the third is LNG fuel tank. Among these three components, this paper is focused on the LNG fuel tank which was developed by DSME so called ‘ACT-iB’ (ACT-iB: Aluminum Cargo Tank Independent type B). This paper describes engineering works such as structural analysis, crack propagation & leakage analysis and temperature distribution analysis for the application of ACT-iB to LNG fueled vessel. From this development, it was concluded that LNG fueled technologies are ready to large container ship application in structural point of view.
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Muntean, Vasile horia, and Marius Otesteau. "QOE-ORIENTED MULTIMEDIA DELIVERY ALGORITHM FOR E-LEARNING IN NEXT GENERATION WIRELESS NETWORKS." In eLSE 2012. Editura Universitara, 2012. http://dx.doi.org/10.12753/2066-026x-12-128.
Повний текст джерелаАнотація:
During the last years, many research efforts in e-learning were focused on developing new content delivery algorithms able to improve the quality of the learning process from content distribution point of view. This is a pressing problem as an increasing number of users are accessing learning content from mobile devices via wireless networks. E-learning involves multiple activities (i.e. web browsing, video and audio streaming, interactive voice calls and ftp background traffic exchange) and various applications that are generating a rich traffic mix. Managing traffic flows is a difficult problem, especially when they are delivered over wireless networks. This is because wireless technologies have limited radio resources and are highly susceptible of being affected by environmental factors, traffic load, number of clients and their mobility patterns. Additionally delivering multimedia traffic with large bandwidth requirements and high sensitivity to loss and delay variations in these wireless environments at high quality levels constitutes significant challenge. Moreover if the end goal is learning and involves users with various profiles, there is an important pressure in developing excellent adaptive solutions to distribute the multimedia content. The paper will describe in detail a novel solution for adaptive multimedia content delivery over wireless networks, the Dynamic Quality-Oriented Adaptation Scheme (DQOAS) which focuses on mobile e-learning. The proposed algorithm concentrates on performing multimedia content management in accordance with end-user learning profile, including their preferences and network conditions. By using DQOAS the end-user quality of experience (QoE) during learning process is improved, as shown in previous papers that investigates the benefits of the algorithm when IEEE802.11 networks are used. The paper presents also the behavior of DQOAS for multimedia content delivery in next generation networks, and in particular over Long Term Evolution (LTE) networks. LTE is an all-IP network technology standardised by the 3rd Generation Partnership Project (3GPP) in Release 8 which uses new multiple access schemes on the air interface. Orthogonal Frequency Division Multiple Access (OFDMA) is used in the downlink and Single Carrier Frequency Division Multiple Access (SC-FDMA) is employed in the uplink to fulfil all the ambitious requirements for data rate, spectrum efficiency, latency, and capacity. Another important technique used is Multiple Input Multiple Output (MIMO) that involves using multiple transmitters and receivers to achieve higher bit rates and improved coverage. An important aspect in LTE is Quality of Service (QoS) support. The 3GPP QoS concept is based on traffic differentiation and prioritization of data flows, using network-initiated bearers in conjunction with simple QoS profiles based on QoS Class Identifiers (QCI). This paper proposes a new QoS delivery parameter mapping which complements LTE QoS class mapping, most beneficial for the case of e-learning traffic mix, in order to obtain higher end-user QoE levels when used in conjunction with DQOAS. The proposed solution improves the overall QoE for the end-user. The paper will be structured as follows. Section II will present the technical aspects and the studies performed by researchers regarding LTE QoS parameters and scheduling in case of traffic mix connections for both downlink and uplink. Section III will describe the DQOAS algorithm. Section IV will present the functioning of the algorithm followed by test results in section V. Conclusions will be drawn in section VI.
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Delenne, Bruno, and Laurent Mode. "Modeling and Simulation of Pressure Oscillations in a Gas Pressure Regulator." In ASME 2000 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/imece2000-1980.
Повний текст джерелаАнотація:
Abstract Pressure stability on gas networks is a major concern for designers and operators of Gaz de France transmission and distribution networks. Pressure level is controlled by pressure regulators. To improve the process control and optimise the design of pressure regulating stations (PRS), experimental and numerical studies have been carried out by the Research and Development Division. The purpose of this paper is to provide an analytical model for pilot controlled gas pressure regulators and to determine the operating conditions that avoiding oscillating pressure regime. Frequency and amplitude of the oscillations depend on many parameters such as flow rate, inlet and outlet pressure mean levels, the downstream volume size, the length of the sensing line or diameter of the outlet pipe. Particular attention is required to represent pressure loss and flow dynamics in pipes and process lines. The model has been developed under the ALLAN.® Simulation environment, a general software for the description and simulation of dynamic systems. It turned out from simulations and measurements that the upstream pressure and the volume of the downstream buffer are very sensitive parameters that influence amplitude and frequency. From a qualitative point of view, numerical and experimental results are in good agreement.
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Pistirica, Sorin andrei, Victor Asavei, Alexandru Egner, and Ovidiu mihai Poncea. "IMPACT OF DISTRIBUTED FILE SYSTEMS AND COMPUTER NETWORK TECHNOLOGIES IN ELEARNING ENVIRONMENTS." In eLSE 2014. Editura Universitatii Nationale de Aparare "Carol I", 2014. http://dx.doi.org/10.12753/2066-026x-14-012.
Повний текст джерелаАнотація:
Usually high education is expensive for most of the top universities in the world. Therefore eLearning platforms provide a way of affordable education with an effective cost of investments. In the last decade, cloud computing research and adoption increased greatly due to its many advantages including economic benefits, ease of management, power saving and so on. Mainly, it provides the means to organize and deliver a wide variety of software services including eLearning environments. Along with cloud computing, file systems solutions were improved to meet requirements imposed by the distribution characteristics of clouds. The distribution level of file systems, data management, data seek methods and many other features of distributed file systems, influence performance of eLearning environments. Distributed file systems started with Andrew File System, still used today, continued with Google File System - a parallel and distributed file system suitable for Google search engine and Ceph - one of the most innovative distributed file system, developed a few years ago and considered the new dream network distributed file system. It has a very good distribution level, security, high availability and many other characteristics. Also, clouds are constructed over computer networks topologies. Basically, topologies are different types of graphs, each with a different set of advantages and disadvantages. In this article we have studied how distributed file systems over computer network clusters influence eLearning environments from an architectural point of view and how its performance may be improved. We also propose a high level architecture of cloud platforms more suitable for eLearning software by outlining several advantages that overcome issues related to distributed eLearning. In our proposed architecture, we use Ceph as a data storage environment and several domestic network topologies. In the end, we study how Software Define Network and Open Flow could model the clouds environment in a more suitable way for eLearning applications.
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Mantha, S., L. Mongeau, and T. Siegmund. "Dynamic Digital Image Correlation of a Dynamic Physical Model of the Vocal Folds." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-81457.
Повний текст джерелаАнотація:
An experimental study of the vibratory deformation of the human vocal folds was conducted. Experiments were performed using model vocal folds [1, 2], Fig. 1, made of silicone rubber implemented into an air supply system, Fig. 2. The material used to cast the model is an isotropic homogeneous material, [3] with a tangent modulus E=5 kPa at ε = 0, i.e. elastic properties similar to those of the human vocal fold cover [4]. The advantages of the use of model larynx systems over the use of excised larynges include easy accessibility to fundamental studies of the vocal fold vibration without invasive testing. Acoustic analysis of voice or electroglottography provide certain insight into voice production processes but optical techniques for the study of vocal fold vibrations have drawn considerable attention. Videoendoscopy, stroboscopy, high-speed photography, and kymography have shown to provide a visual impression of vocal fold dynamics but are limited in providing insight into the fundamental deformation processes of the vocal folds. Quantitative measures of deformation have been conducted through micro-suture techniques but are invasive and allows for measurements of only view image points. Laser triangulation is non-invasive but is limited to only one local measurement point. Here, digital image correlation technique with the software VIC 3D [5] is applied. For the experimental set-up see Fig. 2. The analysis consists of (1) stereo correlation to obtain in-plane displacements and (2) stereo triangulation step to obtain out-of-plane deformation. For the stereo correlation images of the object at two different stages of deformation are compared. A point in the image of the undeformed object is matched with the corresponding point in the deformed stage. “Subsets” of digital images are traced via their gray value distribution from the undeformed reference image to the deformed image. The uniqueness of the matching is enabled by the creation of a speckle pattern on the object’s surface. Here, a white pigment is mixed into the silicone rubber and subsequently black enamel paint is sprayed onto the superior surface of the vocal folds. The stereo triangulation requires two images of the object at each stage of deformation. These are obtained in a single CCD frame by placing a beam splitter in the optical axis between camera and object. These images provide a “left” and “right” view of the model larynx. Thus, the deformed shape of the vocal folds can be obtained. The method allows for noninvasive measurement of the full-field displacement fields. Images of the superior surface of the model larynx are obtained by the use of a high speed digital camera with a frame rate of 3000 frames per second allowing for more than 30 image frames for each vibration cycle. For the 3D digital image correlation analysis two images of the object are obtained for each time instance as a beam splitter is placed in the optical axis between the camera and the model larynx. Phonation frequencies and onset pressure are given in Fig. 3, showing that the model larynx behavior is close to actual physiological data. Figs 4(a) and (b) provide superior views of the model larynx at maximum glottal opening and at glottal closure, respectively. As one example of measured strain fields, Figs 5(a) and (b) depict the distributions of the transverse strain component, on the glottal surface in a contour plot on the deformed superior surface. The knowledge of the distribution of this strain component is relevant to the assessment of the impact of vocal fold collision on potential tissue damage. In the position of maximum opening the vocal folds are deformed by a combination of a bulging-type deformation and the opening movement. At this time instance, the transverse strains at the medial surface are found to be negative, an indication of Poisson’s deformation. During the closing stage, vocal folds collide and simultaneously a mode 3 vibration pattern emerges. Closure of the glottal opening is not complete and two incomplete closure areas are formed during the closure stage. These open areas are located at the anterior and posterior ends of the model larynx, see Fig. 4(b). The finding of this type of incomplete closure is agreement with both actual glottal measurements [6] and 3D finite element simulations of [7]. Transverse strains during that stage are now positive and considerably larger that during the opening stage. Finally, Fig. 6 depicts the time evolution of the out of plane displacements along the medial surface for the closing phase and Fig. 7 depicts the maximum values of the longitudinal strain (at the coronal section of the medial surface) in dependence of the flow rate. These examples of measurements indicate that the DIC method is promising for studies of vocal fold dynamics.