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1.
This paper profiles the types of research activity that have been published in EJIS from 1997 to 2007. Our analysis includes variables such as the most productive authors, citation analysis, universities associated with the most research publications, geographic diversity, authors’ background, subject areas most often investigated, unit of analysis and research methodologies. The classification of the topics and methodologies used by the most highly published authors will help prospective authors gauge whether their paper is suitable for EJIS. The major geographical source of information system (IS) research published in EJIS is from AIS region 2 (Europe, the Middle East and Africa), but with a substantial AIS region 1 (American-based researchers and universities) and AIS region 3 (Asia–Pacific) contribution. The most common research method used is the case study approach, with other methods such as surveys and library research also used frequently. IS management and IS development are the two most researched IS topics published in EJIS. This research and results reported in this paper are comparable with a previous paper published about the Information Systems Journal. Any further such studies will thus be able to make similar comparisons between these journals and any others that have subsequently been covered in this way. The paper concludes with the need for more substantive research on the topic if journal comparisons are to achieve their potential.  相似文献   

2.
In order to explore scientific writing in Information Systems (IS) journals, we adopt a combination of historical and rhetorical approaches. We first investigate the history of universities, business schools, learned societies and scientific articles. This perspective allows us to capture the legacy of scientific writing standards, which emerged in the 18th and 19th centuries. Then, we focus on two leading IS journals (EJIS and MISQ). An historical analysis of both outlets is carried out, based on data related to their creation, evolution of editorial statements, and key epistemological and methodological aspects. We also focus on argumentative strategies found in a sample of 436 abstracts from both journals. Three main logical anchorages (sometimes combined) are identified, and related to three argumentative strategies: ‘deepening of knowledge’, ‘solving an enigma’ and ‘addressing a practical managerial issue’. We relate these writing norms to historical imprints of management and business studies, in particular: enigma-focused rhetorics, interest in institutionalized literature, neglect for managerially grounded rhetoric and lack of reflexivity in scientific writing. We explain this relation as a quest for academic legitimacy. Lastly, some suggestions are offered to address the discrepancies between these writing norms and more recent epistemological and theoretical stances adopted by IS researchers.  相似文献   

3.
This paper aims to shed light on the dynamics of information systems (IS) as a discipline in the making. We use the ideas of the sociologist Abbott to propose three different stages of a discipline's development: differentiation, competition, and absorption. These stages reflect how disciplines go through different cycles and how they acquire, consolidate or lose elements of knowledge. We map these stages using citation and co-citation analyses of two main IS academic journals (EJIS and MISQ) from 1995 to 2008. Our results indicate that IS is currently in a stage of absorption, with research being consolidated around the theme of ‘IS acceptance’. Dominant models and frameworks related to this theme are predictive and thus lend themselves usable for positivistic and quantitative research. In this stage there is also a healthy degree of variety in IS including dormant elements which could reignite. Implications derived from our findings aim to help in the consolidation and extension of knowledge about IS in both academia and practice.  相似文献   

4.
Instance matching is the problem of determining whether two instances describe the same real-world entity or not. Instance matching plays a key role in data integration and data cleansing, especially for building a knowledge base. For example, we can regard each article in encyclopedias as an instance, and a group of articles which refers to the same real-world object as an entity. Therefore, articles about Washington should be distinguished and grouped into different entities such as Washington, D.C (the capital of the USA), George Washington (first president of the USA), Washington (a state of the USA), Washington (a village in West Sussex, England), Washington F.C. (a football club based in Washington, Tyne and Wear, England), Washington, D.C. (a novel). In this paper, we proposed a novel instance matching approach Active Instance Matching with Pairwise Constraints, which can bring the human into the loop of instance matching. The proposed approach can generate candidate pairs in advance to reduce the computational complexity, and then iteratively select the most informative pairs according to the uncertainty, influence, connectivity and diversity of pairs. We evaluated our approach one two publicly available datasets AMINER and WIDE-NUS and then applied our approach to the two large-scale real-world datasets, Baidu Baike and Hudong Baike, to build a Chinese knowledge base. The experiments and practice illustrate the effectiveness of our approach.  相似文献   

5.
Systems of equations of the form X i =φ i (X 1,…,X n ) (1 i n) are considered, in which the unknowns are sets of natural numbers. Expressions φ i may contain the operations of union, intersection and elementwise addition \(S+T=\{m+n\mid m\in S\), nT}. A system with an EXPTIME-complete least solution is constructed in the paper through a complete arithmetization of EXPTIME-completeness. At the same time, it is established that least solutions of all such systems are in EXPTIME. The general membership problem for these equations is proved to be EXPTIME-complete. Among the consequences of the result is EXPTIME-completeness of the compressed membership problem for conjunctive grammars.  相似文献   

6.
Information systems, which are responsible for driving many processes in our lives (health care, the web, municipalities, commerce and business, among others), store information in the form of logs which is often left unused. Process mining, a discipline in between data mining and software engineering, proposes tailored algorithms to exploit the information stored in a log, in order to reason about the processes underlying an information system. A key challenge in process mining is discovery: Given a log, derive a formal process model that can be used afterward for a formal analysis. In this paper, we provide a general approach based on satisfiability modulo theories (SMT) as a solution for this challenging problem. By encoding the problem into the logical/arithmetic domains and using modern SMT engines, it is shown how two separate families of process models can be discovered. The theory of this paper is accompanied with a tool, and experimental results witness the significance of this novel view of the process discovery problem.  相似文献   

7.
In this research we studied the assimilation process of a technological innovation (i.e. technovation) called Radio Frequency Identification (RFID). Like many other technovations, RFID is considered as a revolutionary one, but its assimilation is an evolutionary process. Here, we extended the conventional assimilation theories and initiated an intellectual argument by introducing extension as an important stage of assimilation, which is contextual and highly relevant for RFID assimilation process. Data for the empirical tests were collected via survey from 221 livestock farms in Australia that are using RFID for livestock identification and tracing. We examined ten Technology-Organization-Environmental (TOE) factors on four stages of RFID assimilation process. Empirical results, based on Partial Least Square (PLS)-based Structural Equation Modelling (SEM), suggest that assimilation of RFID technovation does involve four stages: initiation, adoption, routinization, and extension. We also found that one single factor may have different effect on different stages of assimilation, which may even be different directioned. For instance, external environmental uncertainty has a positive impact on RFID adoption while it has a negative impact on RFID extension. The paper discusses the results and practical implications in detail.  相似文献   

8.
We say that an s-subset of codewords of a code X is (s, l)-bad if X contains l other codewords such that the conjunction of these l words is covered by the disjunction of the words of the s-subset. Otherwise, an s-subset of codewords of X is said to be (s, l)-bad. A binary code X is called a disjunctive (s, l) cover-free (CF) code if X does not contain (s, l)-bad subsets. We consider a probabilistic generalization of (s, l) CF codes: we say that a binary code is an (s, l) almost cover-free (ACF) code if almost all s-subsets of its codewords are (s, l)-good. The most interesting result is the proof of a lower and an upper bound for the capacity of (s, l) ACF codes; the ratio of these bounds tends as s→∞ to the limit value log2 e/(le).  相似文献   

9.
A new representation is proved of the solutions of initial boundary value problems for the equation of the form u xx (x, t) + r(x)u x (x, t) ? q(x)u(x, t) = u tt (x, t) + μ(x)u t (x, t) in the section (under boundary conditions of the 1st, 2nd, or 3rd type in any combination). This representation has the form of the Riemann integral dependent on the x and t over the given section.  相似文献   

10.
We study the properties of possible static, spherically symmetric configurations in k-essence theories with the Lagrangian functions of the form F(X), X?,α ?,α. A no-go theorem has been proved, claiming that a possible black-hole-like Killing horizon of finite radius cannot exist if the function F(X) is required to have a finite derivative dF/dX. Two exact solutions are obtained for special cases of kessence: one for F(X) = F 0 X 1/3, another for F(X) = F 0|X|1/2 ? 2Λ, where F 0 and Λ are constants. Both solutions contain horizons, are not asymptotically flat, and provide illustrations for the obtained nogo theorem. The first solution may be interpreted as describing a black hole in an asymptotically singular space-time, while in the second solution two horizons of infinite area are connected by a wormhole.  相似文献   

11.
This paper considers a conflict situation on the plane as follows. A fast evader E has to break out the encirclement of slow pursuers P j1,...,j n = {P j1,..., P jn }, n ≥ 3, with a miss distance not smaller than r ≥ 0. First, we estimate the minimum guaranteed miss distance from E to a pursuer P a , a ∈ {j 1,..., j n }, when the former moves along a given straight line. Then the obtained results are used to calculate the guaranteed estimates to a group of two pursuers P b,c = {P b , P c }, b, c ∈ {j 1,..., j n }, bc, when E maneuvers by crossing the rectilinear segment P b P c , and the state passes to the domain of the game space where E applies a strategy under which the miss distance to any of the pursuers is not decreased. In addition, we describe an approach to the games with a group of pursuers P j1,... jn , n ≥ 3, in which E seeks to break out the encirclement by passing between two pursuers P b and P c , entering the domain of the game space where E can increase the miss distance to all pursuers by straight motion. By comparing the guaranteed miss distances with r for all alternatives b, c ∈ {j 1,..., j n }, bc, and a ? {b, c}, it is possible to choose the best alternative and also to extract the histories of the game in which the designed evasion strategies guarantee a safe break out from the encirclement.  相似文献   

12.
Tree patterns represent important fragments of XPath. In this paper, we show that some classes \({\mathcal{C}}\) of tree patterns exhibit such a property that, given a finite number of compatible tree patterns \({P_1, \ldots, P_n\in \mathcal{C}}\), there exists another pattern P such that P 1, . . . , P n are all contained in P, and for any tree pattern \({Q\in \mathcal{C}}\), P 1, . . . , P n are all contained in Q if and only if P is contained in Q. We experimentally demonstrate that the pattern P is usually much smaller than P 1, . . . , P n combined together. Using the existence of P above, we show that testing whether a tree pattern, P, is contained in another, \({Q\in \mathcal{C}}\), under an acyclic schema graph G, can be reduced to testing whether P G , a transformed version of P, is contained in Q without any schema graph, provided that the distinguished node of P is not labeled *. We then show that, under G, the maximal contained rewriting (MCR) of a tree pattern Q using a view V can be found by finding the MCR of Q using V G without G, when there are no *-nodes on the distinguished path of V and no *-nodes in Q.  相似文献   

13.
Given a tree T=(V,E) of n nodes such that each node v is associated with a value-weight pair (val v ,w v ), where value val v is a real number and weight w v is a non-negative integer, the density of T is defined as \(\frac{\sum_{v\in V}{\mathit{val}}_{v}}{\sum_{v\in V}w_{v}}\). A subtree of T is a connected subgraph (V′,E′) of T, where V′?V and E′?E. Given two integers w min? and w max?, the weight-constrained maximum-density subtree problem on T is to find a maximum-density subtree T′=(V′,E′) satisfying w min?≤∑vV w v w max?. In this paper, we first present an O(w max? n)-time algorithm to find a weight-constrained maximum-density path in a tree T, and then present an O(w max? 2 n)-time algorithm to find a weight-constrained maximum-density subtree in T. Finally, given a node subset S?V, we also present an O(w max? 2 n)-time algorithm to find a weight-constrained maximum-density subtree in T which covers all the nodes in S.  相似文献   

14.
We consider a class of graphs G(n, r, s) = (V (n, r),E(n, r, s)) defined as follows:
$$V(n,r) = \{ x = ({x_{1,}},{x_2}...{x_n}):{x_i} \in \{ 0,1\} ,{x_{1,}} + {x_2} + ... + {x_n} = r\} ,E(n,r,s) = \{ \{ x,y\} :(x,y) = s\} $$
where (x, y) is the Euclidean scalar product. We study random subgraphs G(G(n, r, s), p) with edges independently chosen from the set E(n, r, s) with probability p each. We find nontrivial lower and upper bounds on the clique number of such graphs.
  相似文献   

15.
Resource-conscious technologies for cutting sheet material include the ICP and ECP technologies that allow for aligning fragments of the contours of cutouts. In this work, we show the mathematical model for the problem of cutting out parts with these technologies and algorithms for finding cutting tool routes that satisfy technological constraints. We give a solution for the problem of representing a cutting plan as a plane graph G = (V,F,E), which is a homeomorphic image of the cutting plan. This has let us formalize technological constraints on the trajectory of cutting the parts according to the cutting plan and propose a series of algorithms for constructing a route in the graph G = (V,F,E), which is an image of an admissible trajectory. Using known coordinates of the preimages of vertices of graph G = (V,F,E) and the locations of fragments of the cutting plan that are preimages of edges of graph G = (V,F,E), the resulting route in the graph G = (V,E) can be interpreted as the cutting tool’s trajectory.The proposed algorithms for finding routes in a connected graph G have polynomial computational complexity. To find the optimal route in an unconnected graph G, we need to solve, for every dividing face f of graph G, a travelling salesman problem on the set of faces incident to f.  相似文献   

16.
We prove that any balanced incomplete block design B(v, k, 1) generates a nearresolvable balanced incomplete block design NRB(v, k ? 1, k ? 2). We establish a one-to-one correspondence between near-resolvable block designs NRB(v, k ?1, k ?2) and the subclass of nonbinary (optimal, equidistant) constant-weight codes meeting the generalized Johnson bound.  相似文献   

17.
An outer-connected dominating set in a graph G = (V, E) is a set of vertices D ? V satisfying the condition that, for each vertex v ? D, vertex v is adjacent to some vertex in D and the subgraph induced by V?D is connected. The outer-connected dominating set problem is to find an outer-connected dominating set with the minimum number of vertices which is denoted by \(\tilde {\gamma }_{c}(G)\). In this paper, we determine \(\tilde {\gamma }_{c}(S(n,k))\), \(\tilde {\gamma }_{c}(S^{+}(n,k))\), \(\tilde {\gamma }_{c}(S^{++}(n,k))\), and \(\tilde {\gamma }_{c}(S_{n})\), where S(n, k), S +(n, k), S ++(n, k), and S n are Sierpi\(\acute {\mathrm {n}}\)ski-like graphs.  相似文献   

18.
Credit-assignment schemas are widely applied by providing fixed or flexible credit distribution formulas to evaluate the contributions of coauthors of a scientific publication. In this paper, we propose an approach named First and Others (F&O) counting. By introducing a tuning parameter α and a weight β, two new properties are obtained: (1) flexible assignment of credits by modifying the formula (with the change of α) and applying preference to the individual author by adjusting the weights (with the change of β), and (2) calculation of the credits by separating the formula for the first author from others. With formula separation, the credit of the second author shows an inflection point according to the change of α. The developed theorems and proofs concerning the modification of α and β reveal new properties and complement the base theory for informetrics. The F&O schema is also adapted when considering the policy of ‘first-corresponding-author-emphasis’. Through a comparative analysis using a set of empirical data from the fields of chemistry, medicine, psychology, and the Harvard survey data, the performance of the F&O approach is compared with those of other methods to demonstrate its benefits by the criteria of lack of fit and coefficient of determination.  相似文献   

19.
This paper introduces α-systems of differential inclusions on a bounded time interval [t0, ?] and defines α-weakly invariant sets in [t0, ?] × ?n, where ?n is a phase space of the differential inclusions. We study the problems connected with bringing the motions (trajectories) of the differential inclusions from an α-system to a given compact set M ? ?n at the moment ? (the approach problems). The issues of extracting the solvability set W ? [t0, ?] × ?n in the problem of bringing the motions of an α-system to M and the issues of calculating the maximal α-weakly invariant set Wc ? [t0, ?] × ?n are also discussed. The notion of the quasi-Hamiltonian of an α-system (α-Hamiltonian) is proposed, which seems important for the problems of bringing the motions of the α-system to M.  相似文献   

20.
Design of rectangular concrete-filled steel tubular (CFT) columns has been a big concern owing to their complex constraint mechanism. Generally, most existing methods are based on simplified mechanical model with limited experimental data, which is not reliable under many conditions, e.g., columns using high strength materials. Artificial neural network (ANN) models have shown the effectiveness to solve complex problems in many areas of civil engineering in recent years. In this paper, ANN models were employed to predict the axial bearing capacity of rectangular CFT columns based on the experimental data. 305 experimental data from articles were collected, and 275 experimental samples were chosen to train the ANN models while 30 experimental samples were used for testing. Based on the comparison among different models, artificial neural network model1 (ANN1) and artificial neural network model2 (ANN2) with a 20-neuron hidden layer were chosen as the fit prediction models. ANN1 has five inputs: the length (D) and width (B) of cross section, the thickness of steel (t), the yield strength of steel (f y), the cylinder strength of concrete (fc). ANN2 has ten inputs: D, B, t, f y, fc, the length to width ratio (D/B), the length to thickness ratio (D/t), the width to thickness ratio (B/t), restraint coefficient (ξ), the steel ratio (α). The axial bearing capacity is the output data for both models.The outputs from ANN1 and ANN2 were verified and compared with those from EC4, ACI, GJB4142 and AISC360-10. The results show that the implemented models have good prediction and generalization capacity. Parametric study was conducted using ANN1 and ANN2 which indicates that effect law of basic parameters of columns on the axial bearing capacity of rectangular CFT columns differs from design codes.The results also provide convincing design reference to rectangular CFT columns.  相似文献   

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