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Review of Conventional and Innovative Technologies for Fire Retrofitting of Existing Buildings  [PDF]
Farshad Zahmatkesh, Ali M. Memari
Open Journal of Civil Engineering (OJCE) , 2017, DOI: 10.4236/ojce.2017.72014
Abstract: Fire effects can be one of the most harmful conditions that any building may experience throughout its service life. Developing practical protection methods and concepts against potential fire disasters in buildings has been an important consideration in design of buildings in recent decades. Rapid developments in technology have heightened the demand for new and innovative fire protection systems in comparison with conventional and traditional methods. Such a need for new technologies is in particular of greater importance when it comes to existing buildings. Retrofitting an existing building for fire safety is a greater challenge compared with designing a new building using materials and components that have more desirable and superior fire rating to begin with. Furthermore, strategies to design a new building that includes state-of-the-art fire safety features are also different from solutions that may be more suitable for retrofitting an existing building. This paper presents a review of the literature concerning conventional and new or innovative retrofitting methods for fire safety of buildings. Advantages and disadvantages of different fire protection devices and methods as available and understood from the literature are mentioned. Study of fire safety systems shows that each has its drawbacks. Comparison of the results shows that disadvantages of a solitary system for retrofitting against fire can be improved by using a combination of several fire safety concepts or methods simultaneously.
Rational solutions to the Pfaff lattice and Jack polynomials  [PDF]
Mark Adler,Vadim B. Kuznetsov,Pierre van Moerbeke
Physics , 2002,
Abstract: The finite Pfaff lattice is given by commuting Lax pairs involving a finite matrix L (zero above the first subdiagonal) and a projection onto Sp(N). The lattice admits solutions such that the entries of the matrix L are rational in the time parameters t_1,t_2,..., after conjugation by a diagonal matrix. The sequence of polynomial tau-functions, solving the problem, belongs to an intriguing chain of subspaces of Schur polynomials, associated to Young diagrams, dual with respect to a finite chain of rectangles. Also, this sequence of tau-functions is given inductively by the action of a fixed vertex operator. As examples, one such sequence is given by Jack polynomials for rectangular Young diagrams, while another chain starts with any two-column Jack polynomial.
Effects of Foundation Models on Jack-up Site Assessment  [cached]
ZHANG Jian,TANG Wenxian,SU Shijie,SU Shijie
Advances in Natural Science , 2012, DOI: 10.3968/j.ans.1715787020120504.688
Abstract: In order to investigate effects of different foundation models on jack-up site assessment, numerical simulation of a jack-up is presented based on fix joint, pin joint, linear springs and elastic-plastic model. The hull, leg, hull-leg connection is modelled using equivalent beam, beam element, spring element, respectively. Environmental loads, such as steady current, wind, wave, inertial load and buoyancy, are also included in the numerical model. Static and natural frequency extraction analysis of the jack-up is then performed in elevated condition. Finally, static and natural response rules are proposed for the four foundation models. The results show that, the horizontal hull displacement, maximum leg stress, loads on spudcan B and horizontal moment on spudcan A decrease as the rotational stiffness increases, while the natural frequency, vertical load and horizontal load on spudcan A increase with the increasing rotational stiffness. And the responses for elastic-plastic model are close to the pin joint. The proposed modelling and analyzing method is effective and reliable, which could provide guidance for jack-up development and assessment. Key words: Jack-up; Fix joint; Pin joint; Linear springs; Elastic-plastic model; Numerical simulation
Jack polynomials, generalized binomial coefficients and polynomial solutions of the generalized Laplace's equation  [PDF]
S. Chaturvedi
Physics , 1997, DOI: 10.1142/S0217732398000772
Abstract: We discuss the symmetric homogeneous polynomial solutions of the generalized Laplace's equation which arises in the context of the Calogero-Sutherland model on a line. The solutions are expressed as linear combinations of Jack polynomials and the constraints on the coefficients of expansion are derived. These constraints involve generalized binomial coefficients defined through Jack polynomials. Generalized binomial coefficients for partitions of $k$ upto $k=6$ are tabulated.
FUNCTIONAL REQUIREMENTS FOR STABILITY OF JACK UP DRILLING RIGS ON WORKING POSITION  [PDF]
Damir Zadravec,Zdenko Kri?tafor
Rudarsko-Geolo?ko-Naftni Zbornik , 2008,
Abstract: Jack up drilling platforms are offshore drilling units composed by drilling rig situated on naval structure without self propelling device. Jack up drilling rigs are units used for drilling and completion of deep well bores in offshore oil and gas exploration industry or field development. By reaching the theoretical center of gravity and equilibrium while towing and balance of acting forces on the unit while operations on location ensures the stability and safe mode of operations of entire unit. Penetration of legs spud cans in sea bad produced by weight of unit and acting of preload force, depending on geotechnical characteristics, type and bearing capacity of sea bad, and taking in consideration working environmental forces which acts on unit (wind, waves, sea current, ice, snow) ensures proper foundation, environmental forces balancing and safe mode of operations.
Selection of the Capillary Tubes for Retrofitting in Refrigeration Appliances
A.S. Raut,U.S.Wankhede
International Journal of Engineering Science and Technology , 2011,
Abstract: Retrofitting the refrigeration appliances using the capillary tube is reviewed in this paper. If the refrigerant is changed in the existing system, the COP of the system will be affected. It is necessary to do some modifications in the existing system and retrofit it. Changes in compressor design are too complicated and expensive. Hence modification in capillary tube dimensions is preferred so as to compensate for theperformance of the system.
Vehicle jack with wedge mechanism
Sunday A. Oke
Maejo International Journal of Science and Technology , 2008,
Abstract: In many developing countries, particularly Nigeria,the high cost of production of a vehicle jack and the prevailing economic situation has made the commercial production of vehicle jacks difficult. Thus, the development of an appropriate technology for a vehicle jackwould be of vital utility to vehicle users. This paper presents the design and construction of a low-price, simple mechanical jack with wedge mechanism to provide a lift of about 160 mm with a self-locking capability for both small- and medium-sized vehicles. The design calculationsinvolve the evaluation of applied force required, the screw shaft design, and the lift head design analysis. The fabricated jack was tested on some small and medium vehicles, which resulted in a good lift without any pre-manual lifting. The jack weighs about 4 kg and costs about N1000 per unit.
Energy retrofitting design of existing building stock. The case study of social housing La riqualificazione energetica e architettonica del patrimonio edilizio recente. Il caso dei quartieri di edilizia residenziale pubblica
Annarita Ferrante,Elena Cattani,Nicola Bartolini,Giovanni Semprini
In_Bo : Ricerche e Progetti per il Territorio, la Città e l'Architettura , 2012, DOI: 10.6092/issn.2036-1602/3489
Abstract: Within the current discussion on the feasibility of energy retrofitting buildings’ operations, the pilot-study experience developed in the district Corticella in Bologna offers an updated review of the possible methods and techniques to be applied to reduce the energy consumption in existing buildings. In particular, the re-design of buildings, starting from the basic hypothesis of standard interventions, such as insulation and replacement of windows, has been further developed to envisage higher transformation scenarios such as the volumetric adds-on and roof-top elevations; these solutions are shown as possible means to: i) enhance the technical and economic feasibility of the retrofitting actions; ii) compensate the stiffness of existing building types; iii) promote adaptable, flexible, user-centred solutions as possible tools for communication with the human being, as “technical guides” to help the increase of his knowledge and awareness on energy-conscious behaviour. Nell’ambito dell’attuale riflessione sulla fattibilità degli interventi di riqualificazione energetica, l’esperienza condotta nel quartiere Corticella a Bologna propone una revisione aggiornata dei metodi e delle tecnologie finalizzate al contenimento energetico degli edifici. In particolare, a partire da ipotesi di intervento standard, come isolamento e sostituzione degli infissi, nella riqualificazione degli edifici sono state ipotizzate soluzioni di incremento volumetrico; tali soluzioni sono indicate come possibili strumenti per: i) potenziare la fattibilità tecnico-economica delle opere di trasformazione; ii) superare la rigidezza dei tipi edilizi esistenti; iii) promuovere soluzioni adattabili, flessibili, rivolte all’utenza, utilizzandole come mezzo di comunicazione con la componente umana, come “guida” tecnica per elevarne il grado di conoscenza e consapevolezza in materia di risparmio energetico.
Practice of Integration for the Intelligent Analysis Platform
情报分析平台的集成化实践

Wang Xiaomei,Wu Qingqiang,Han Tao,
王小梅
,吴清强,韩涛

现代图书情报技术 , 2007,
Abstract: Based on analysis of system functionality of the current intelligence analysis tools,this paper details the basic design and integration study for the intelligent analysis platform.Meanwhile,the paper provides solutions to users' requirements combining existing analysis tools and ongoing study for this platform.
Jack vertex operators and realization of Jack functions  [PDF]
Wuxing Cai,Naihuan Jing
Mathematics , 2011, DOI: 10.1007/s10801-013-0438-9
Abstract: We give an iterative method to realize general Jack functions from Jack functions of rectangular shapes. We first show some cases of Stanley's conjecture on positivity of the Littlewood-Richardson coefficients, and then use this method to give a new realization of Jack functions. We also show in general that vectors of products of Jack vertex operators form a basis of symmetric functions. In particular this gives a new proof of linear independence for the rectangular and marked rectangular Jack vertex operators. Thirdly a generalized Frobenius formula for Jack functions was given and was used to give new evaluation of Dyson integrals and even powers of Vandermonde determinant.
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