Improving the Efficiency of a Nuclear Power Plant Using a Thermoelectric Cogeneration System

The efficiencies of nuclear power plants are rather poor having the ratio %30 by using the conventional energy/exergy tools. According to that information, large amount of energy is wasted during condensation and thrown out to the environment. Thermoelectric generator (TEG) system has a potential to be used as a heat exchanging technology to produce power with a relatively low efficiency (about 5%) and it can transform the temperature difference into electricity and generate clean electrical energy. In the present study, we offer a novel system to recover the waste heat from a VVER-1000 nuclear power plant. The heat transfer of the TEG is analyzed numerically with respect to the various temperature ranges and constant mass flow rate of the exhaust steam entering the system. In the analyses, different hot temperature ranges (35ºC, 45ºC and 55ºC) and a constant cold temperature (i.e. 18ºC) are used for a HZ-20 thermoelectric module and it has been proven that the designed TEG can produce the maximum output power of 76,956 MW for a temperature difference ∆T=37 and the conversion efficiency of 3.854% sits. The TEG is designed for the condenser of a 1000 MW nuclear power plant. It\u27s shown that about 2.0% increasing in the power plant efficiency is expected by using the selected thermoelectric generator in the condensation cycle.Article History: Received: July 15th 2017; Received: October 17th 2017; Accepted: February 13rd 2018; Available onlineHow to Cite This Article: Terzi, R. and Kurt, E. (2018), Improving the efficiency of a nuclear power plant using a thermoelectric cogeneration system, Int. Journal of Renewable Energy Development, 7(1), 77-84.https://doi.org/10.14710/ijred.7.1.77-8

Traffic placement policies for a multi-band network

Recently protocols were introduced that enable the integration of synchronous traffic (voice or video) and asynchronous traffic (data) and extend the size of local area networks without loss in speed or capacity. One of these is DRAMA, a multiband protocol based on broadband technology. It provides dynamic allocation of bandwidth among clusters of nodes in the total network. A number of traffic placement policies for such networks are proposed and evaluated. Metrics used for performance evaluation include average network access delay, degree of fairness of access among the nodes, and network throughput. The feasibility of the DRAMA protocol is established through simulation studies. DRAMA provides effective integration of synchronous and asychronous traffic due to its ability to separate traffic types. Under the suggested traffic placement policies, the DRAMA protocol is shown to handle diverse loads, mixes of traffic types, and numbers of nodes, as well as modifications to the network structure and momentary traffic overloads

Oxygen-related traps in pentacene thin films: Energetic position and implications for transistor performance

We studied the influence of oxygen on the electronic trap states in a pentacene thin film. This was done by carrying out gated four-terminal measurements on thin-film transistors as a function of temperature and without ever exposing the samples to ambient air. Photooxidation of pentacene is shown to lead to a peak of trap states centered at 0.28 eV from the mobility edge, with trap densities of the order of 10(18) cm(-3). These trap states need to be occupied at first and cause a reduction in the number of free carriers, i.e. a consistent shift of the density of free holes as a function of gate voltage. Moreover, the exposure to oxygen reduces the mobility of the charge carriers above the mobility edge. We correlate the change of these transport parameters with the change of the essential device parameters, i.e. subthreshold performance and effective field-effect mobility. This study supports the assumption of a mobility edge for charge transport, and contributes to a detailed understanding of an important degradation mechanism of organic field-effect transistors. Deep traps in an organic field-effect transistor reduce the effective field-effect mobility by reducing the number of free carriers and their mobility above the mobility edge.Comment: 13 pages, 14 figures, to be published in Phys. Rev.

Extremely high data-rate, reliable network systems research

Significant progress was made over the year in the four focus areas of this research group: gigabit protocols, extensions of metropolitan protocols, parallel protocols, and distributed simulations. Two activities, a network management tool and the Carrier Sensed Multiple Access Collision Detection (CSMA/CD) protocol, have developed to the point that a patent is being applied for in the next year; a tool set for distributed simulation using the language SIMSCRIPT also has commercial potential and is to be further refined. The year's results for each of these areas are summarized and next year's activities are described

Lunar Resource Utilization: Development of a Reactor for Volatile Extraction from Regolith

The extraction and processing of planetary resources into useful products, known as In- Situ Resource Utilization (ISRU), will have a profound impact on the future of planetary exploration. One such effort is the RESOLVE (Regolith and Environment Science, Oxygen and Lunar Volatiles Extraction) Project, which aims to extract and quantify these resources. As part of the first Engineering Breadboard Unit, the Regolith Volatiles Characterization (RVC) reactor was designed and built at the NASA Glenn Research Center. By heating and agitating the lunar regolith, loosely bound volatiles, such as hydrogen and water, are released and stored in the reactor for later analysis and collection. Intended for operation on a robotic rover, the reactor features a lightweight, compact design, easy loading and unloading of the regolith, and uniform heating of the regolith by means of vibrofluidization. The reactor performance was demonstrated using regolith simulant, JSC1, with favorable results

Disaster Planning and Management

Recent events such as hurricanes, tsunamis, earthquakes, power outages, and the threat of pandemics have highlighted our vulnerability to natural disasters. This vulnerability is exacerbated by many organizations\u27 increasing dependence on computer, telecommunications, and other technologies, and trends toward integrating suppliers and business partners into everyday business operations. In response many organizations are implementing disaster recovery planning processes. In this paper we discuss how to identify threats and scenarios; how to articulate the disaster recovery strategies; and four elements of the generic disaster recovery plan: Mitigation, preparedness, response, and recovery. We then provide examples of software that can help disaster recovery professionals in the planning and implementation process. Finally we present some trends that will reinforce the criticality of the issue

NASA's In-Situ Resource Utilization Project: Current Accomplishments and Exciting Future Plans

The utilization of Space resources has been identified in publications for over 40 years for its potential as a "game changing" technology for the human exploration of Space. It is called "game changing" because of the mass leverage possible when local resources at the exploration destination arc used to reduce or even eliminate resources that are brought from the Earth. NASA, under the Exploration Technology Development Program has made significant investments in the development of Space resource utilization technologies as a part of the In-Situ Resource Utilization (ISRU) project. Over the last four years, the ISRU project has taken what was essentially an academic topic with lots of experimentation but little engineering and produced near-full-scale systems that have been demonstrated. In 2008 & again in early 2010, systems that could produce oxygen from lunar soils (or their terrestrial analogs) were tested at a lunar analog site on a volcano in Hawaii. These demonstrations included collaborations with International Partners that made significant contributions to the tests. The proposed federal budget for Fiscal Year 2011 encourages the continued development and demonstration of ISRU. However it goes beyond what the project is currently doing and directs that the scope of the project be expanded to cover destinations throughout the inner solar system with the potential for night demonstrations. This paper will briefly cover the past accomplishments of the ISRU project then move to a di scussion of the plans for the project's future as NASA moves to explore a new paradigm for Space Exploration that includes orbital fuel depots and even refueling on other planetary bodies in the solar system

Atmospheric Co2 And O3 Alter The Flow Of 15n In Developing Forest Ecosystems

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/116984/1/ecy200788102630.pd

Radiolabeled Protein Composition and Method for Radiation Synovectomy

A radiolabeled protein composition adapted for radiation therapy which comprises a radioisotope and a protein material containing about 6 or more percent amino acids which have a sulfhydryl-containing side chain. A method for carrying out radiation synovectomy of arthritic joints. Rhenium radiolabeled protein micro- spheres are administered which contain cysteine and other amino acids. A method for radiolabeling a protein composition whereby the composition is treated with a reducing agent capable of reducing disulfides to sulfhydryls prior to radiolabeling