scholarly journals Considerations for Air Power Systems

1968 ◽  
Author(s):  
Robert S. Johnson
Keyword(s):  
Power Systems ◽  
Capital Investment ◽  
Electrical Power ◽  
The Other ◽  
Compressed Air ◽  
Plant Management ◽  
Pressurized Water ◽  
The Difference ◽  
Generating Equipment ◽  
Pumping Equipment

The availability of compressed air in plants today is viewed by many as being in the same category with electricity, water and gas. The one major difference, however, lies in the fact that for most industrial plants compressed air is generated within the plant proper and the compressor and related equipment is maintained by “In-Plant Personnel”, while electricity and its related generating equipment and clean water and its related purification and pumping equipment are supplied from outside facilities and maintained by others. The difference thusly becomes clear. In the case of compressed air, the air compressor and related accessories represent a capital investment on the part of the user, while the other services (electricity, water, gas, etc.) are essentially services paid for on a usage basis and charged as a monthly cost of operation. Although there is a difference as to the source of the utility, compressed air being considered as such is expected to be every bit available in sufficient capacity and pressure by plant management as are ampers and voltage in the case of electrical power or gallons of pure pressurized water. This difference requires the watchful eye of plant management and maintenance personnel, for, unlike the other utilities, the compressed air source and usage is their complete responsibility and not that of the local utilities. Paper published with permission.

A New Algorithm and Computation Approach for Economic Dispatch with Prohibited Operating Zones in Power Systems

2005 ◽  
Vol 23 (4) ◽  
pp. 267-275
Author(s):  
Nurettin Çetinkaya ◽  
Abdullah Ürkmez ◽  
İsmet Erkmen ◽  
Tankut Yalçinöz
Keyword(s):  
Power Systems ◽  
Electrical Power ◽  
Quadratic Function ◽  
Power Production ◽  
Standard Test ◽  
The Other ◽  
Economic Load Dispatch ◽  
Electrical Power Systems ◽  
Prohibited Operating Zones ◽  
Cost Curves

This paper presents a new algorithm and computation approach to solve the economic load dispatch (ELD) in electrical power systems. We applied a new power formula to solve the ELD problem. If production units cost curves are represented properly then ELD becomes more correct. In this respect we assumed that production units have prohibited operating zones. Cost curves of the production units are generally accepted as piece-wise quadratic function. The power production is cheaper since we do not use the production units in the prohibited operating zones. The proposed method and algorithm are compared to other ELD methods on the standard test systems. The proposed method solve the dispatch problem faster than the other ELD methods.

Electric Power Supply of German NPPs: Defence in Depth, Protection Against External Hazards and Retrofitting as a Consequence of the Fukushima Accident

2016 ◽  
Author(s):  
Sebastian A. Meiss
Keyword(s):  
Power Systems ◽  
Power Supply ◽  
Power Plants ◽  
Science And Technology ◽  
Electrical Power ◽  
Regulatory Framework ◽  
Original Design ◽  
Fukushima Accident ◽  
Pressurized Water ◽  
Electric Power Supply

The history of building and operating nuclear power plants (NPPs) in Germany dates back to the late 1950s and will come to an end in 2022. By then all NPPs still in operation will have to shut down in a defined sequence, according to the revisions made to the German Atomic Energy Act as a consequence of the accident at the Fukushima Dai-Ichi NPP. Nine out of 17 NPPs have already been shut down permanently as a consequence. Due to the progress in science and technology, the design of the electrical power supply of German NPPs got more complex and hardened against various scenarios with time. The latest generation of NPPs built in Germany in the late 1980’s — the pressurized water reactor of type Konvoi — was designed with Defence in Depth in mind. They are connected to several voltage levels of the power grid and feature two layers of AC emergency power systems, each of which fulfills the n+2 redundancy criteria. The second of those layers is especially hardened against the influence of certain internal and external events and is part of an emergency control system which can keep the plant in a safe state autonomously for 10 hours under certain conditions. With this being the state of science and technology at that time in Germany, most of the older NPPs in operation had been retrofitted by 2011 with systems that were designed to partially compensate for these plants’ weaker original design. Various events such as the accident at the Chernobyl 4 NPP in 1986 and also the accident at the Fukushima Dai-Ichi NPP in 2011 led to changes in the German regulatory framework and recommendations to the NPPs for further retrofitting activities. In the regime of electrical power supply, the latest changes in requirements and corresponding retrofitting of the NPPs in operation include mobile diesel generators with corresponding, redundant feeding points, an enhanced coping capability for station blackouts with only DC-power left and measures to ensure bringing back AC-power within the available time. In this presentation the author gives an overview over the historic development of the electric design in German NPPs and discuss details of the most recently added requirements on retrofitting — e.g. in the new regulatory framework — to enhance the robustness of the electrical power supply of those NPPs. An update on the progress on the actual retrofitting process of the German NPPs with respect to these new requirements is given.

Voltage Quality in Electrical Power Systems

2001 ◽  
Author(s):  
J. Schlabbach ◽  
D. Blume ◽  
T. Stephanblome
Keyword(s):  
Power Systems ◽  
Electrical Power ◽  
Electrical Power Systems ◽  
Voltage Quality

Enhancement of ADP-induced Platelet Aggregation by Adrenaline in Vivo and Its Prevention

1973 ◽  
Vol 29 (02) ◽  
pp. 490-498 ◽  
Author(s):  
Hiroh Yamazaki ◽  
Itsuro Kobayashi ◽  
Tadahiro Sano ◽  
Takio Shimamoto
Keyword(s):  
Platelet Count ◽  
Platelet Aggregation ◽  
Platelet Rich Plasma ◽  
The Other ◽  
Endothelial Surface ◽  
Important Interaction ◽  
Blood Coagulability ◽  
The Difference

SummaryThe authors previously reported a transient decrease in adhesive platelet count and an enhancement of blood coagulability after administration of a small amount of adrenaline (0.1-1 µg per Kg, i. v.) in man and rabbit. In such circumstances, the sensitivity of platelets to aggregation induced by ADP was studied by an optical density method. Five minutes after i. v. injection of 1 µg per Kg of adrenaline in 10 rabbits, intensity of platelet aggregation increased to 115.1 ± 4.9% (mean ± S. E.) by 10∼5 molar, 121.8 ± 7.8% by 3 × 10-6 molar and 129.4 ± 12.8% of the value before the injection by 10”6 molar ADP. The difference was statistically significant (P<0.01-0.05). The above change was not observed in each group of rabbits injected with saline, 1 µg per Kg of 1-noradrenaline or 0.1 and 10 µg per Kg of adrenaline. Also, it was prevented by oral administration of 10 mg per Kg of phenoxybenzamine or propranolol or aspirin or pyridinolcarbamate 3 hours before the challenge. On the other hand, the enhancement of ADP-induced platelet aggregation was not observed in vitro, when 10-5 or 3 × 10-6 molar and 129.4 ± 12.8% of the value before 10∼6 molar ADP was added to citrated platelet rich plasma (CPRP) of rabbit after incubation at 37°C for 30 second with 0.01, 0.1, 1, 10 or 100 µg per ml of adrenaline or noradrenaline. These results suggest an important interaction between endothelial surface and platelets in connection with the enhancement of ADP-induced platelet aggregation by adrenaline in vivo.

Energy Approximation

2017 ◽  
Author(s):  
Philip Isett
Keyword(s):  
Main Lemma ◽  
The Other ◽  
Coarse Scale ◽  
Continuous Solutions ◽  
Material Derivative ◽  
Energy Variation ◽  
Energy Approximation ◽  
The Difference ◽  
Derivatives Of

This chapter presents the equations and calculations for energy approximation. It establishes the estimates (261) and (262) of the Main Lemma (10.1) for continuous solutions; these estimates state that we are able to accurately prescribe the energy that the correction adds to the solution, as well as bound the difference between the time derivatives of these two quantities. The chapter also introduces the proposition for prescribing energy, followed by the relevant computations. Each integral contributing to the other term can be estimated. Another proposition for estimating control over the rate of energy variation is given. Finally, the coarse scale material derivative is considered.

Pengaruh Unsur Budaya Lokal dalam Ungkapan Berbahasa Perancis

Metahumaniora ◽  
2017 ◽  
Vol 7 (3) ◽  
pp. 378
Author(s):  
Vincentia Tri Handayani
Keyword(s):  
Mental Representation ◽  
Cultural Context ◽  
Oral Tradition ◽  
Minimal Element ◽  
The Other ◽  
Local Culture ◽  
Community Groups ◽  
Cultural Community ◽  
The Difference ◽  
Complex Words

AbstrakFolklor yang menghasilkan tradisi lisan merupakan perwujudan budaya yang lahirdari pengalaman kelompok masyarakat. Salah satu bentuk tradisi lisan adalah ungkapan yangmengandung unsur budaya lokal dalam konstruksinya yang tidak dimiliki budaya lainnya.Ungkapan idiomatis memberikan warna pada bahasa melalui penggambaran mental. Dalambahasa Perancis, ungkapan dapat berupa locution dan expression. Perbedaan motif acuansuatu ungkapan dapat terlihat dari pengaruh budaya masyarakat pengguna bahasa. Sebuahleksem tidak selalu didefinisikan melalui unsur minimal, tidak juga melalui kata-kata,baik kata dasar atau kata kompleks, namun dapat melalui kata-kata beku yang maknanyatetap. Hubungan analogis dari makna tambahan yang ada pada suatu leksem muncul dariidentifikasi semem yang sama. Semem tersebut mengarah pada term yang diasosiasikan danyang diperkaya melalui konteks (dalam ungkapan berhubungan dengan konteks budaya).Kata kunci: folklor, ungkapan, struktur, makna idiomatis, kebudayaanAbstractFolklore which produces the oral tradition is a cultural manifestation born out theexperience of community groups. One form of the oral tradition is a phrase that containsthe elements of local culture in its construction that is not owned the other culture. Theidiomatic phrase gives the color to the language through the mental representation. InFrench, the expression can consist of locution and expression. The difference motivesreference of an expression can be seen from the influence of the cultural community thelanguage users. A lexeme is not always defined through a minimal element, nor throughwords, either basic or complex words, but can be through the frost words whose meaningsare fixed. The analogical connection of the additional meanings is on a lexeme arises fromthe identification of the same meaning. The meaning ‘semem’ leads to the associated termsand which are enriched through the context (in idiom related to the cultural context).Keywords : folklore, idioms, structure, idiom meaning, cultureI PENDAHULUAN

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