Business process management as the 'killer app' for Petri nets

Since their inception in 1962, Petri nets have been used in a wide variety of application domains. Although Petri nets are graphical and easy to understand, they have formal semantics and allow for analysis techniques ranging from model checking and structural analysis to process mining and performance analysis. Over time Petri nets emerged as a solid foundation for Business Process Management (BPM) research. The BPM discipline develops methods, techniques, and tools to support the design, enactment, management, and analysis of operational business processes. Mainstream business process modeling notations and workflow management systems are using token-based semantics borrowed from Petri nets. Moreover, state-of-the-art BPM analysis techniques are using Petri nets as an internal representation. Users of BPM methods and tools are often not aware of this. This paper aims to unveil the seminal role of Petri nets in BPM.

Authorisation management in business process environments: An authorisation model and a policy model

This thesis provides two main contributions. The first one is BP-TRBAC, a unified authorisation model that can support legacy systems as well as business process systems. BP-TRBAC supports specific features that are required by business process environments. BP-TRBAC is designed to be used as an independent enterprise-wide authorisation model, rather than having it as part of the workflow system. It is designed to be the main authorisation model for an organisation. The second contribution is BP-XACML, an authorisation policy language that is designed to represent BPM authorisation policies for business processes. The contribution also includes a policy model for BP-XACML. Using BP-TRBAC as an authorisation model together with BP-XACML as an authorisation policy language will allow an organisation to manage and control authorisation requests from workflow systems and other legacy systems.

Role-based process view derivation and composition

The process view concept deploys a partial and temporal representation to adjust the visible view of a business process according to various perception constraints of users. Process view technology is of practical use for privacy protection and authorization control in process-oriented business management. Owing to complex organizational structure, it is challenging for large companies to accurately specify the diverse perception of different users over business processes. Aiming to tackle this issue, this article presents a role-based process view model to incorporate role dependencies into process view derivation. Compared to existing process view approaches, ours particularly supports runtime updates to the process view perceivable to a user with specific view merging operations, thereby enabling the dynamic tracing of process perception. A series of rules and theorems are established to guarantee the structural consistency and validity of process view transformation. A hypothetical case is conducted to illustrate the feasibility of our approach, and a prototype is developed for the proof-of-concept purpose.

Sustainable forest management : ecologically sound and socially accepted

This dissertation explored the ecological dimension of ecologically sustainable forest management in boreal forests, and factors of the socio-cultural dimension that affect how the concept of ecologically sustainable forest management is defined. My approach was problem-oriented and generalistic-holistic. I examined associations between the abundances of wildlife groups (grouse, large predators, small predators, ungulates) and Siberian flying squirrels, and their co-occurrence with tree structural characteristics at the regional level. The trade-offs between ecological, social and economic sustainability in forestry were explored at the regional scale. I identified a potential 'shopping basket' of regional indicators for ecologically sustainable forest management, combining the relative abundance of Siberian flying squirrels, a wildlife richness index (WRI) for grouse, diversity indices of saw-timber trees, tree age classes and the proportion of old-growth (> 120 yr) forests. I suggest that the close association between forestry activity, the proportion of young forests (< 40 yr) and a WRI for small predators can be considered as potential 'alarm bells' for regions in which the creation of trade-offs (negative relationships) between economic and ecological components of sustainable forestry is ongoing. Explorative analyses revealed negative relationships between forestry activity and a WRI of 16 game species, the WRI for grouse and tree age diversity. Socially sustainable communities compete less intensively with ecological components of forests than communities where forestry is important. Interestingly, forest ownership types (farmers, other private forest owners, the forestry industry, the State) correlated significantly with the co-occurrence of flying squirrels, grouse and diverse forest structural characteristics rather than, for instance, with the total number of protection areas, suggesting that private forest ownership can lead to increased ecological sustainability. I examined forest actors’ argumentation to identify characteristics that affect the interpretation of ecologically sustainable forest management. Four argumentation frame types were constructed: information, work, experience and own position based. These differed in terms of their emphasis on external experts or own experiences. The closer ecologically sustainable forest management is to the forest actor’s daily life, the more profiled policy tools (counselling, learning through experiences) are needed to guide management behaviour to become more ecologically sound. I illustrated that forest actors interpret, use and understand information through meaningful framing. I analysed the extent to which ecological research information has been perceived in the Forestry Development Centre TAPIO’s recommendations and revised PEFC Finland criteria. We noticed that the political value for decaying wood was much lower in PEFC Finland critera (4 m3) than could be expected as a socially acceptable level (9 m3) or ecologically sound (10-20 m3). I consider it important for scientists to join political discourses and become involved in policy making concerning sustainable forest management to learn to present their results in a way that is reasonable from the user’s perspective.

U12-type Spliceosome: Localization and Effects of Splicing Efficiency on Gene Expression

The removal of non-coding sequences, introns, is an essential part of messenger RNA processing. In most metazoan organisms, the U12-type spliceosome processes a subset of introns containing highly conserved recognition sequences. U12-type introns constitute less than 0,5% of all introns and reside preferentially in genes related to information processing functions, as opposed to genes encoding for metabolic enzymes. It has previously been shown that the excision of U12-type introns is inefficient compared to that of U2-type introns, supporting the model that these introns could provide a rate-limiting control for gene expression. The low efficiency of U12-type splicing is believed to have important consequences to gene expression by limiting the production of mature mRNAs from genes containing U12-type introns. The inefficiency of U12-type splicing has been attributed to the low abundance of the components of the U12-type spliceosome in cells, but this hypothesis has not been proven. The aim of the first part of this work was to study the effect of the abundance of the spliceosomal snRNA components on splicing. Cells with a low abundance of the U12-type spliceosome were found to inefficiently process U12-type introns encoded by a transfected construct, but the expression levels of endogenous genes were not found to be affected by the abundance of the U12-type spliceosome. However, significant levels of endogenous unspliced U12-type intron-containing pre-mRNAs were detected in cells. Together these results support the idea that U12-type splicing may limit gene expression in some situations. The inefficiency of U12-type splicing has also promoted the idea that the U12-type spliceosome may control gene expression, limiting the mRNA levels of some U12-type intron-containing genes. While the identities of the primary target genes that contain U12-type introns are relatively well known, little has previously been known about the downstream genes and pathways potentially affected by the efficiency of U12-type intron processing. Here, the effects of U12-type splicing efficiency on a whole organism were studied in a Drosophila line with a mutation in an essential U12-type spliceosome component. Genes containing U12-type introns showed variable gene-specific responses to the splicing defect, which points to variation in the susceptibility of different genes to changes in splicing efficiency. Surprisingly, microarray screening revealed that metabolic genes were enriched among downstream effects, and that the phenotype could largely be attributed to one U12-type intron-containing mitochondrial gene. Gene expression control by the U12-type spliceosome could thus have widespread effects on metabolic functions in the organism. The subcellular localization of the U12-type spliceosome components was studied as a response to a recent dispute on the localization of the U12-type spliceosome. All components studied were found to be nuclear indicating that the processing of U12-type introns occurs within the nucleus, thus clarifying a question central to the field. The results suggest that the U12-type spliceosome can limit the expression of genes that contain U12-type introns in a gene-specific manner. Through its limiting role in pre-mRNA processing, the U12-type splicing activity can affect specific genetic pathways, which in the case of Drosophila are involved in metabolic functions.

Developing a Multidisciplinary Process View of IFC Standardization

The industry foundation classes (IFC) file format is one of the most complex and ambitious IT standardization projects currently being undertaken in any industry, focusing on the development of an open and neutral standard for exchanging building model data. Scientific literature related to the IFC standard has dominantly been technical so far; research looking at the IFC standard from an industry standardization per- spective could offer valuable new knowledge for both theory and practice. This paper proposes the use of IT standardization and IT adoption theories, supported by studies done within construction IT, to lay a theoretical foundation for further empirical analysis of the standardization process of the IFC file format.

Relationship Between The Impedance Matrix And The Transfer Matrix With Specific Reference To Symmetrical, Reciprocal And Conservative Systems

Impedance matrix and transfer matrix methods are often used in the analysis of linear dynamical systems. In this paper, general relationships between these matrices are derived. The properties of the impedance matrix and the transfer matrix of symmetrical systems, reciprocal systems and conservative systems are investigated. In the process, the following observations are made: (a) symmetrical systems are not a subset of reciprocal systems, as is often misunderstood; (b) the cascading of reciprocal systems again results in a reciprocal system, whereas cascading of symmetrical systems does not necessarily result in a symmetrical system; (c) the determinant of the transfer matrix, being ±1, is a property of both symmetrical systems and reciprocal systems, but this condition, however, is not sufficient to establish either the reciprocity or the symmetry of the system; (d) the impedance matrix of a conservative system is skew-Hermitian.

Vortex dislocations in wake-type flow induced by spanwise disturbances

Vortex dislocations in wake-type flow induced by three types of spanwise disturbances superimposed on an upstream velocity profile are investigated by direct numerical simulations. Three distinct modes of vortex dislocations and flow transitions have been found. A local spanwise exponential decay disturbance leads to the appearance of a twisted chainlike mode of vortex dislocation. A stepped spanwise disturbance causes a streamwise periodic spotlike mode of vortex dislocation. A spanwise sinusoidal wavy disturbance with a moderate waviness causes a strong unsteadiness of wake behavior. This unsteadiness starts with a systematic periodic mode of vortex dislocation in the spanwise direction followed by the spanwise vortex shedding suppressed completely with increased time and the near wake becoming a steady shear flow. Characteristics of these modes of vortex dislocation and complex vortex linkages over the dislocation, as well as the corresponding dynamic processes related to the appearance of dislocations, are described by examining the variations of vortex lines and vorticity distribution. The nature of the vortex dislocation is demonstrated by the substantial vorticity modification of the spanwise vortex from the original spanwise direction to streamwise and vertical directions, accompanied by the appearance of noticeable vortex branching and complex vortex linking, all of which are produced at the locations with the biggest phase difference or with a frequency discontinuity between shedding cells. The effect of vortex dislocation on flow transition, either to an unsteady irregular vortex flow or suppression of the Kaacutermaacuten vortex shedding making the wake flow steady state, is analyzed. Distinct similarities are found in the mechanism and main flow phenomena between the present numerical results obtained in wake-type flows and the experimental-numerical results of cylinder wakes reported in previous studies.

Enhancing Kerr nonlinearity via spontaneously generated coherence

A theoretical investigation is carried out into the effect of spontaneously generated coherence on the Kerr nonlinearity of general three-level systems of Lambda, ladder, and V-shape types. It is found, with spontaneously generated coherence present, that the Kerr nonlinearity can be clearly enhanced. In the Lambda- and ladder-type systems, the maximal Kerr nonlinearity increases and at the same time enters the electromagnetically induced transparency window as the spontaneously generated coherence intensifies. As for the V-type system, the absorption property is significantly modified and therefore enhanced Kerr nonlinearity without absorption occurs for certain probe detunings. We attribute the enhancement of Kerr nonlinearity mainly to the presence of an extra atomic coherence induced by the spontaneously generated coherence.

Controlling the group velocity in a five-level K-type atomic system

The properties of a five-level K-type system are investigated. With the controlling fields, the properties of the dispersion and absorption of the system are changed greatly. The system can produce anomalous dispersion regions with absorption and normal dispersion regions with absorption or transparency. Furthermore, the group velocity can be varied from subluminal to superluminal by varying the intensity of the controlling field and the probe detunings in principle. (C) 2008 Elsevier B.V. All rights reserved.

Transmission matrices and lumped parameter models for continuous systems

The use of transmission matrices and lumped parameter models for describing continuous systems is the subject of this study. Non-uniform continuous systems which play important roles in practical vibration problems, e.g., torsional oscillations in bars, transverse bending vibrations of beams, etc., are of primary importance.

A new approach for deriving closed form transmission matrices is applied to several classes of non-uniform continuous segments of one dimensional and beam systems. A power series expansion method is presented for determining approximate transmission matrices of any order for segments of non-uniform systems whose solutions cannot be found in closed form. This direct series method is shown to give results comparable to those of the improved lumped parameter models for one dimensional systems.

Four types of lumped parameter models are evaluated on the basis of the uniform continuous one dimensional system by comparing the behavior of the frequency root errors. The lumped parameter models which are based upon a close fit to the low frequency approximation of the exact transmission matrix, at the segment level, are shown to be superior. On this basis an improved lumped parameter model is recommended for approximating non-uniform segments. This new model is compared to a uniform segment approximation and error curves are presented for systems whose areas very quadratically and linearly. The effect of varying segment lengths is investigated for one dimensional systems and results indicate very little improvement in comparison to the use of equal length segments. For purposes of completeness, a brief summary of various lumped parameter models and other techniques which have previously been used to approximate the uniform Bernoulli-Euler beam is a given.

Características microbiológicas e clínicas das infecções por Acinetobacter spp. e Pseudomonas aeruginosa em Unidade de Terapia Intensiva Cardíaca de um Hospital Universitário do Rio de Janeiro

As infecções em cirurgia cardíaca ainda apresentam um cenário importante nas infecções associadas à assistência a saúde (IAAS), favorecendo ao paciente à aquisição de infecções por micro-organimos multirreristentes. Este trabalho teve como objetivo avaliar o perfil de resistência a antimicrobianos, verificar a presença de genes que codificam as enzimas dos tipos oxacilinases e metalo-beta-lactamases e descrever as características demográficas e clínicas dos pacientes colonziados/infectados por Acinetobacter spp. e P.aeruginosa internados no Centro de Terapia Intensiva Cardíaca do HUPE no período de 2005 a 2010. A maioria das 46 amostras de Acinetobacter spp e das 35 de P.aeruginosa foram de origem respiratória seguido de sangue. A maioria das amostras de A. baumannii apresentou altos percentuais de resistência a: ceftazidina, cefepime, piperacilina-sulbactam, ciprofloxacin, ceftriaxona e CIM ≥32 μg/mL para os carbapenêmicos. Uma amostra foi resistente a Polimixina B. O gene blaOXA-23 foi detectado em 65% das amostras e uma amostra apresentou o gene blaOXA-24. Não foram detectados os genes blaOXA-58-like e blaOXA-143. Para P. aeruginosa os percentuais de resistência para todos os antimicrobianos foram inferiores a 32%. Quatro amostras apresentaram resistência intermediária a polimixina B e nenhum gene de resistência foi detectado. Os prontuários dos pacientes foram analisados a fim de associar as características clínicas com os processos infecciosos identificados e seu desfecho clínico. Na análise por tipo de micro-organismo associado ao processo infeccioso à idade acima de 70 anos, DM e uso da ventilação mecânica por tempo prolongado foi maior no grupo dos pacientes que apresentaram infecção por P.aeruginosa. O IAM, a ICC em internações anteriores e suas complicações (choque cardiogênico e arritmia) tiveram impacto na mortalidade na série de pacientes (p<0,05). A insuficiência renal entre todas as comorbidades foi à única que teve associação com a mortalidade (OR= 8,3). Não houve associação entre a mortalidade e o micro-organismo que causou a infecção (Acinetobacter spp. p=0,3 e P.aeruginosa p=0,2) ou a resistência a carbapenêmicos (p=0,5). Foram observados dois casos de mediastinte por Acinetobacter spp. e dois por P. aeruginosa sendo um achado inédito no Brasil até o momento.

Avaliação de biocidas no controle da corrosão microbiologicamente induzida do aço carbono 1020 por bactérias redutoras de sulfato

Bactérias redutoras de sulfato (BRS) são os principais micro-organismos envolvidos na corrosão microbiologicamente induzida (CMI). Estas bactérias reduzem o sulfato, tendo como resultado a produção de H2S, o que pode influenciar os processos anódico e catódico na corrosão de materiais metálicos em ambientes marinhos, óleos e solos úmidos. Uma das formas de prevenir e controlar esse tipo de corrosão é a adição de biocidas ao meio corrosivo. Esta dissertação tem como objetivo avaliar o uso de biocidas no controle da CMI do aço AISI 1020 por BRS. Para isto, o comportamento da CMI no aço foi avaliado em água do mar sintética, em condições de anaerobiose, na ausência e na presença de uma cultura mista contendo BRS. Um biocida natural (óleo de alho) e outro comercial (glutaraldeído) foram utilizados para controlar a corrosão causada por estas bactérias. Duas formas de adição de biocida foram avaliadas: antes da formação do biofilme e após sua formação na superfície do metal. O crescimento microbiano na superfície do aço foi avaliado através da quantificação das BRS sésseis, pelo método do número mais provável (NMP). O comportamento eletroquímico do aço, na ausência e na presença de BRS e também para os ensaios com biocidas, foi estudado através das técnicas de espectroscopia de impedância eletroquímica (EIE) e polarização potenciodinâmica, sempre usando água do mar sintética como meio eletrolítico. A formação de biofilme e de produtos de corrosão na superfície do aço foi observada através da microscopia eletrônica de varredura (MEV). Os resultados mostraram que o aço exposto ao meio contendo BRS apresentou um processo corrosivo mais acelerado, quando comparado aos sistemas na ausência de micro-organismo. Esse processo foi evidenciado por um decréscimo na magnitude do arco capacitivo, nos ensaios de EIE, e um aumento da densidade de corrente de corrosão (Icorr), nos ensaios de polarização. Na análise de MEV, foi possível observar a formação de corrosão localizada após a remoção do biofilme da superfície. Os ensaios com biocidas, adicionados antes da formação de biofilmes, mostraram uma redução no número de bactérias sésseis, quando comparados com os ensaios sem biocida realizados pelo mesmo período de tempo (7 dias). Foi verificado também um decréscimo do processo corrosivo do aço, evidenciado através de aumento nos arcos capacitivos, nos ensaios de EIE e pelos menores valores de Icorr nos ensaios de polarização, quando comparados com o biofilme formado sem biocidas, nas mesmas condições. Apesar de não ter inibido completamente o crescimento das BRS sésseis, o óleo de alho apresentou maior redução no processo corrosivo quando comparado ao glutaraldeído, indicando sua possível aplicação como biocida natural nestas condições. Os ensaios realizados com biocidas adicionados após a formação do biofilme mostraram que o glutaraldeído apresentou alta eficácia em reduzir o número de células sésseis. Já o óleo de alho exibiu uma ação menos efetiva, sugerindo que este composto não conseguiu penetrar completamente a matriz do biofilme. Entretanto, ambos causaram aceleração do processo corrosivo do aço no meio estudado após 7 dias de exposição

Effects of annealing ambient on the formation of compensation defects in InP

Positron annihilation lifetime (PAL) and photoinduced current transient spectroscopies (PICTS) have been employed to study the formation of compensation defects in undoped InP under different annealing processes with pure phosphorus (PP) ambience and iron phosphide (IP) ambience, respectively. The different annealing ambiences convert the as-grown n-type undoped InP into two types of semi-insulating (SI) states. The positron average lifetimes of as-grown InP, PP SI-InP, and IP SI-InP are found to be 246, 251, and 243 ps, respectively, which are all longer than the bulk lifetime of 240 ps, indicating the existence of vacancy-type positron-trapping defects. For as-grown InP, VInH4 complexes are the dominant defects. They dissociate into VInHn(0less than or equal tonless than or equal to3) acceptor vacancies under PP ambience annealing, compensating the residual shallow donors and turning the material semi-insulating. In forming IP SI-InP, diffusion of iron into V-In complexes under IP ambience annealing produces the substitutional compensation defect Fe-In, causing a shorter positron average lifetime. The PICTS measurements show that a group of vacancy-type defects has been suppressed by iron diffusion during the annealing process, which is in good agreement with the PAL results. (C) 2003 American Institute of Physics.

若尔盖自然保护区高原林蛙(Rana kukunoris)扩散模型与景观连接分析

揭示水体中繁殖的两栖动物在异质性景观中的空间扩散特点，探讨景观面积丧失和破碎化对于两栖动物的影响，为两栖动物的保护提供理论依据。本文以四川西北部若尔盖湿地自然保护区的高原林蛙(Rana kukunoris)为研究对象，通过运用地理信息系统及建立景观模型等方法，在分析若尔盖湿地自然保护区范围内现有景观格局的基础上，建立了高原林蛙的景观扩散模型，并模拟了“沼泽→草甸”的湿地逆演化过程下高原林蛙的空间分布与景观连接的变化特点。主要结果是： 1．若尔盖湿地自然保护区呈典型的沼泽—草甸式斑块—基质景观格局。草甸面积占整个景观面积的79.42%，景观蔓延度指数（CONTAG）为79.00远离最小值0而更趋向于最大值100，面积和景观蔓延度指数表明草甸是整个景观中面积占绝对优势且景观连接好的类型，构成了景观的基质，对景观的动态格局演变起主导作用。沼泽面积仅占整个景观面积的18.08%，但却是整个景观中斑块数目最多的单元，占所有斑块数的82.9%。因此沼泽斑块与草甸基质之间的动态结构对高原林蛙的扩散起着决定性的作用。 2．空间扩散模型表明，其它类型的景观不但扩展了高原林蛙的活动范围，而且也为高原林蛙在不同沼泽斑块间的连接提供了通道。高原林蛙的空间扩散区域使得彼此间成斑块化隔离状分布的沼泽形成了潜在景观功能连接，促进了不同斑块间物种的交流。小型沼泽作为垫脚石（stepping-stone），使得整个景观中的相隔距离较远的大型斑块联结为一个功能整体，促进了高原林蛙在整个景观中的相互动态联系。 3．模拟“沼泽→草甸”的湿地逆演化过程表明，大量小型沼泽湿地的消失将会 对在沼泽中繁殖并扩散到其它景观类型中去的高原林蛙造成潜在影响。逆演化过程不仅使沼泽斑块的分布范围，沼泽源斑块的面积和空间扩散面积减少，而且对景观连接也有很大影响。小型沼泽的消失，将使得景观斑块的功能连接变小，使得依靠小型沼泽作为跳板的动物在沼泽斑块之间的移动将变得更加困难。 本文是对生境丧失与破碎化影响下两栖动物的行为反应的一种尝试。影响模型的因素很多，包括动物对各种类型景观的偏好程度，地理数据的精度，及模型的可靠程度都是制约模型准确度的因素。 The spatial diffusion of water—breeding amphibian through heterogeneous landscape and the effects of landscape losing and fragmentation to amphibian were the core theory of the landscape ecology of amphibian. Geographical information system (GIS) and landscape model were used to model the diffused area of Rana kukunoris in Zoige Wetland Natural Reserve. Model was also used to analysis the spatial distribution variation of R. kukunoris and the change of landscape connectivity when simulated the retrogressive succession of landscape. The main results are below: 1. There was peatland—meadow pattern which was typical patch—matrix landscape pattern in Zoige Natural Reserve. The meadow area occupied 79.42% of the entire landscape area, contagion index (CONTAG) was 79.00 which was far away the minimum value (0) but tend to the maximum value (100). Both of these showed that meadow was the largest part and the most continue units. It was shown that meadow was matrix of the landscape, which evolved the leading role to the landscape dynamic pattern. Though their area only occupies 18.08% of entire landscape area, peatlands were according to 82.9% of the total patches. Dynamic of the pattern between peatlands and meadows decided the spatial diffusion of R. kukunoris. 2．The model indicated that the other types of landscape not only expanded diffusion of R. kukunoris, but also have provided the potential channels for frog's connections among different peatlands. The spatial diffusion zone of R. kukunoris forced isolated patch peatlands to be potential landscape functional connectivity. The small peatlands, as stepping-stone, made the large peatlands connect as a functional one and promoted the integrated and dynamic connectivity of R. kukunoris in the whole landscape. 3. The simulation of “peatlands→meadows”retrogressive succession process indicated that the decrease of small peatlands will have potential effect to R. kukunoris because they must bred in peatlands and diffuse to other type of the landscape. Retrogressive succession process not only made the decrease of distribution of peatlands, patches number of peatlands and diffused area of R. kukunoris, but also reduced the connectivity among source patches. As stepping-stone, the disappearance of small peatlands will made the migration of R. kukunoris among patches more difficult. The model was an experiment of the amphibian behavior reaction to habitat losing and fragmentation. There were many factors that could influence the accuracy of model, such as the preference of animals to each type of landscape, the geographical data precision, reliable degree of model.