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14 Ergebnisse
Ergebnisse nach Hochschule und Institut
Publikation Event Data Sources for Enterprise Architecture Documentation(Hochschule für Wirtschaft FHNW, 02/2015) Frei, Michael; Hinkelmann, KnutEnterprise Architecture Management (EAM) has become a widely accepted discipline that concerns itself with the alignment of business and information technology (IT) and deals with the increasing complexity of information system (IS) landscapes. It is the practice of documenting the interrelations of business and IT entities by developing a model of the enterprise architecture (EA). This documentation of the EA acts as basis for planning the future architecture and prioritizing the projects that transform the current architecture. Due to globalizing markets and the fast paced evolution of IT, organizations are forced to become agile and frequently adapt their internal architecture in order to stay competitive. Today, the majority of tasks concerning the maintenance of EA documentation are based on manual methods and are connected to huge data collection efforts. This has a negative impact on the quality and reliability of the EA documentation and therefore diminishes the benefits of EAM. The popularly utilized EA frameworks cover the process of keeping the EA documentation up-to-date only marginally. In recent literature, there has been an effort to automate the EA documentation with the use and integration of different productive IS across the company. It was identified that common IS in organizations not only hold data about the EA, but also can contain events that could be used to trigger EA documentation processes. However, only few concrete implementations of automated EA documentation are examined in research or found in practice, because organizations face several challenges when attempting to integrate IS into an automated EA documentation. This thesis identifies possible sources of EA data and EA events in the form of common IS or databases in today’s enterprises. Further, the thesis develops an evaluation catalogue for potential source candidates in order to recommend a set of suitable documentation techniques for each source. A proof of concept through a case-study at a financial institution demonstrates the feasibility and applicability of the catalogue. The proposed data source selection catalogue for EA documentation supports the identification and selection of productive IS and suitable techniques in order to increase the quality of EA documentation11 - Studentische ArbeitPublikation Learning frequent and periodic usage patterns in smart homes(Hochschule für Wirtschaft FHNW, 31.01.2014) Schweizer, Daniel; Wache, Holger; Witschel, Hans FriedrichThis paper discusses how usage patterns and preferences of smart home inhabitants can be learned efficiently. Such patterns as a baseline of what constitutes normal behavior of inhabitants allows future smart homes to autonomously achieve positive effects like comfort increases, energy savings or improved safety for elderly residents in assisted living homes. The approach for learning usage patterns chosen by this research project, which was carried out as a Master Thesis at FHNW, uses frequent sequential pattern mining algorithms to mine the event data available in smart homes. While other authors have already published possible solutions or at least approaches to the problem, the information presented herein is unique because it is based solely on reallife smart home event data and not data collected in a laboratory trial and/or enriched by additional sensors. Furthermore the project does not only propose one solution but compares the performance of different algorithms regarding completeness/correctness of the results, run times as well as memory consumption and elaborates on the shortcomings of the different solutions. To be able to solve the challenge of learning usage patterns, this project followed the research onion framework by Saunders, et al. (2009) and the design science research paradigm by Vaishnavi & Kuechler (2004): after a research design and a literature review was done, the available secondary data was analyzed in depth before different solutions (including a brute-force algorithm specifically designed for this project as well as adaptations of the three established frequent sequential pattern mining algorithms PrefixSpan, BIDE+ and GapBIDE) were designed, implemented as prototypes in Java and benchmarked against each other. The main findings of the benchmarking done with the prototypes and of the project as such were: • With all four algorithms a reasonable amount of frequent sequential patterns can be found with an input parameter set of pattern length = 2-5 events, minimum support = 0.01 – 0.001, overlapping patterns, wildcarding deactivated. • The traditional frequent sequential pattern mining algorithms like PrefixSpan, BIDE+ or GapBIDE need pre- and post-processing to be able to mine smart home event data. Additionally, if different minimum and maximum lengths of patterns shall be mined, those algorithms need to be run multiple times to report the correct support count. • The run times vary greatly for the different algorithms, BIDE+ being the slowest of the four algorithms. Both GapBIDE and especially PrefixSpan run significantly faster, however, they are outperformed by the brute-force algorithm WSDD developed for this project. • Wildcarding could not fulfill the potential attributed to it at the beginning of the project because no significantly higher support counts can be found with wildcarding being activated. • While WSDD as the fastest algorithms can be recommended without reservations regarding run times, all four benchmarked algorithms showed bad results regarding memory consumption for certain combinations of input parameters. This paper therefore contains six different propositions for lowering the memory consumption, should memory consumption be a concern. • While the aspect of periodic sequential pattern mining was investigated as part of this research project and a manual analysis of the available data showed that periodic patterns exist in smart home events, no satisfactory mining results could be achieved and it is therefore suggested to look into this aspect in a follow-up research project (e.g. by adapting a state-of-the-art periodic (sequential) pattern mining algorithm to the specifics of smart home event data). Overall it can be said that the thesis could prove part of its statement as true: it is possible to learn, in a run-time efficient way, frequent usage patterns and preferences of smart home inhabitants only from event data available within a smart home. With different use cases it could be shown in a theoretical way that the patterns can be used to achieve the aforementioned positive effects like saving electricity or increasing the comfort of smart home inhabitants.11 - Studentische ArbeitPublikation Agility meets Governance of Enterprise IT(Hochschule für Wirtschaft FHNW, 29.10.2014) Diptanshu, Kumar; Asprion, PetraAchievement of continuous competitive advantage in an ever changing business environment together with distinct advancement in technology, require enterprises to consider more efficient ways in their quick responding abilities and in their taking advantage of IT possibilities. Many studies confirmed the important role of Agility and IT/ERP governance in ERP post-implementation phase in this respect. Additionally it was found that agility affects ERP post-implementation phase in various ways and continuous improvement of this phase with customization and business process reengineering plays a vital role for an improved superior agility. Impact and influence of ERP systems in supporting business operations is significant, therefore the effect of post-implementation modification initiatives need to be closely examined. Since these influences of ERP PIP are not adequately studied, there is still gap in the literature regarding this (Oseni et al., 2014). This master thesis addresses the research problem about the lack of knowledge on how IT/ERP governance and agility influences ERP post-implementation phase. To reach this goal, three research questions were identified and a review of the related terms of agility, IT/ERP governance, ERP post-implementation phase and business environment was performed through literature studies. The first question to find the current literature status of ERP post implementation with focus on IT/ERP governance and agility is answered by reviewing of existing literature relating to the topic as an essential first step and foundation when undertaking a research project (Baker, 2000). The second question to find the result about agility affect on ERP post implementation, a qualitative research approach known as Relational Analysis is performed on nine related articles of four selected online journals from last one year. Third question to find the influencing factors impacting the ERP post implementation regard to IT/ERP Governance or/and agility is answered by determining these factors through literature analysis performed on the various related literatures included in foundation. A conceptual research model based on the existing literature is proposed to provide a visual representation of the relationship between the involved concepts. The outcome of the first research question is a table, which summarizes the main literatures topics, focus, and literature support. Outcome of second research question support the mutual promotive relationship between ERP post implementation and agility. Outcome of third question is list of influencing factors impacting ERP post implementation regard to IT/ERP Governance or/and agility. Finally a revised conceptual model is derived to visualize the interpretations of the findings of the research. The findings of the research could be important theoretical contributions to the body knowledge of business information systems. The research has bridged the knowledge gap among agility, IT/ERP governance and post implementation, in relation to the way on how they influence ERP post implementation. This research has specific focus on ERP post implementation with regard to agility and IT/ERP governance.11 - Studentische ArbeitPublikation Critical Infrastructure Information Security Model(Hochschule für Wirtschaft FHNW, 31.01.2015) Schlüter, Michael; Asprion, PetraMalfunction of critical infrastructures have a serious impact on health, safety, security and economic wellbeing of citizens and have therefore to be supremely protected. Today’s cyber threats gain in importance especially for critical infrastructure as they have enormous potential for damage. Critical infrastructures are the backbone of our nation's economy, security and health. Different instruments are available to address various information security topics. Some regulations exist for parts of critical infrastructure sectors. But there is currently no unique security level of critical infrastructure enterprises. Goal of this study is to develop a model for critical infrastructures to prevent and mitigate current cyber risks. Gaps in information security for critical infrastructures were disclosed between available instruments and the needs of critical infrastructure providers. Primary source is based on case study research. Critical infrastructure experts were interviewed to get information about current situations in critical infrastructure enterprises. Books, documentation and journals in the field of information security or critical infrastructure protection are investigated as secondary resources. These sources were used to build a model by prototyping approach, which then was validated by critical infrastructure experts. Analysis of the case study discloses gaps in the area of awareness, cyber risk management, education, funding, regulation and technology. The developed “Critical Infrastructure Information Security Model” describes these areas and shows an improved information security model with focus on cyber risks of critical infrastructures.11 - Studentische ArbeitPublikation Mobile Commerce: Mobile Money Transfer in Ghana(Hochschule für Wirtschaft FHNW, 31.01.2014) Kofi Frimpong, Adasa Nkrumah; Dettling, Walter; Corradini, FlavioMobile money transfer allows people to send money using Short Message Service (SMS). Its low costs, fast speed and no need of having a bank account. The service started in Kenya as MPESA introduced by Safaricom and has since been replicated in other parts of the world especially in developing countries. The service was introduced in Ghana in 2009. Much research has been done in mobile money transfer but mostly focused on the success of MPESA. Very little is known with respect to the service in Ghana. This paper studied the use of mobile money transfer service in Ghana. The study sought to compare the extension and impact of the service as against the successful implementation of Kenya’s MPESA. The objective was to investigate the socioeconomic characteristics of MMT users, their MMT experience, as well as the agents‟ operations. Quantitative and qualitative research method based on the Positivism and the Interpretivism philosophies were used. The survey method using questionnaire was used. The respondents were users and agents of mobile money transfer in Ghana with sample taken from four communities, Ahenkro, Offinso, Buoho, and Kodie, located in the Ashanti region of Ghana. Secondary data was also used. The result of the survey showed that MMT was used to a large extent in Ghana, just as in Kenya; it was concluded that like the survey by Mas & Radcliffe, (2010) which found that 98 percent of users in Kenya were happy with the service, the users in Ghana were equally happy, however, the percentage in Ghana was 88%. Other findings included there were more male users of MMT than female users, the elderly sent mobile money to their younger counterparts, and Formal workers use more mobile money than their informal counterparts; the educational level of the formal senders was higher than the educational level of the corresponding recipient, Siblings are more recipients of mobile money in Ghana; mothers receive more mobile money than fathers; and spouses receive more mobile money than children. Like in Kenya, the popularity and use of mobile phones in Ghana was widespread and reflected the global statistics of mobile phone use; 90% of household owned and could use mobile phone, Unlike in Kenya where M-Ticketing is widely used, the service is not widespread in Ghana. Registration/subscription process was quite mild; however, more efforts needs to be put in place by MNOs in Ghana for effective MMT. Withdrawing money with MMT in Ghana was instant and therefore quite good, there was high usage of the service, cross-net was used in Ghana to a large extent and the main reason was that the recipients were affiliated to a different network, Some of the reasons for the non-use of MMT in Ghana were Complex procedures, delay in withdrawing money, inadequate agents/point of registration, and distrust. Others were inadequate advertisement and illiteracy. On top of the list was inadequate agents/point of registration. There was a high the high proportion of agents who were Senior High School leavers, the agents‟ procedure to becoming MMT agent was found to be well structured, however, their training aspects needed to improvement.11 - Studentische ArbeitPublikation Identity resolution for fraud prevention(Hochschule für Wirtschaft FHNW, 01/2015) Studer, Michael; Witschel, Hans FriedrichThe purpose of this master thesis is to find the best solution for identity resolution between social media networks and bank customers. With the contacts of the identified social media user it should be possible to identify fraud based on circular references of money transactions.The literature shows that identity resolution between multiple offline data sources is well researched. With the emerging social media networks the identity resolution between these networks was also deeply researched. Both problems can be solved by existing solutions. However, identity resolution between offline data and social media networks is not well researched, yet. The thesis is based on design research. In the different phases knowledge was gained trough literature research, interviews and meetings. An artefact was developed to evaluate and optimise the different algorithm variations. The final algorithm was then evaluated with a set of test data. In this work an algorithm is presented, which is able to identify social media users based on bank customer information with an accuracy of 80%. The key to a successful identity resolution lies within the similar data structure of the money transactions of a bank customer and the contacts of a social media profile. The best identity resolution was achieved with different weighting for the different attributes and by the normalisation of the transactions in addition to the normalisation of the name based on the name frequency.The conclusion of this work is that the thesis statement is confirmed. It is possible to correctly identify a person within a social media network based on the information availablefrom a bank customer.11 - Studentische ArbeitPublikation Energy saving in smart homes based on consumer behaviour data(Hochschule für Wirtschaft FHNW, 31.01.2015) Zehnder, Michael; Wache, Holger; Witschel, Hans FriedrichThis paper discusses how energy can be saved in smart homes without lowering the comfort of the inhabitants, based on consumer behaviour data only. A recommender system was designed, that suggests actions for inhabitants without the necessity for installing additional devices, executing manual configuration or having any other interaction with the system. As a consequence of the devastating earthquake and the resulting nuclear disaster that struck Fukushima in March 2011, concerned members of the public and the government agreed on a major reconsideration of the energy policy. However, such a radical rethinking can only be achieved if private households increase their efforts to save energy. Nevertheless, most research approaches conducted in smart homes in the past years, dealt with convenience rather than with sustainability. The aim of this master thesis is to find a way to save energy without causing significant inconveniences for the consumer. Therefore, the following hypothesis was formulated: “It is possible to design a recommender system that can suggest actions in smart homes based on consumer behaviour, which will lower energy usage but not decrease comfort levels”. The approach followed in this paper, is to mine frequent (and/or periodic) patterns in the event data of the inhabitants electricity usages, recorded by a smart home automation system. These patterns are converted into association rules, prioritized and compared with the current behaviour of the inhabitants. If the system detects opportunities to save energy without decreasing the comfort level, it will send a recommendation to the residents. Because the most appropriate research design to prove this hypothesis is design science research, the project follows the methodology to design and implement a functional prototype of a recommender system. At the end of the project, the prototype is evaluated in smart homes under real conditions. The main findings of the project and the concluding field-test of the prototype were: - The project succeeded in identifying possible actions, which can be recommended in smart homes to lower energy usage in smart homes. - Investigations showed how patterns in the behaviour data of the inhabitants can be used to trigger these actions at the right moment, to not lower comfort levels for the inhabitants. - A design has evolved for a recommender system that uses association rules and deterministic finite state machines. - It was identified, that the confidence and the length of a pattern are significant measures to predict if a suggestion does lower comfort or not. Overall, it can be said that this master thesis could verify part of its statement: The prototype demonstrated that it is possible to suggest actions that lower energy usage, but do not decrease comfort levels, while using consumer behaviour data as single source. However, besides the useful recommendations, the system did still recommend actions that did not just lower energy usage, but also the comfort level of the inhabitants. The ratio of useful recommendations, which reached little over 11% during the final test of the prototype, must be increased before broader adaption of the system is possible. Nevertheless, the proof of concept provided by the prototype is the first important step for further research in this field.11 - Studentische ArbeitPublikation Energy Trading in the Smart Stability Network(Hochschule für Wirtschaft FHNW, 30.01.2015) Mettler, Fabian; Wache, HolgerThe current implementation of the electrical grid has not changed since the last 50 years and due to the increase of energy demand the stability of the electrical grid is strongly affected which can result in power cuts respectively blackouts, brownouts or poor quality. One of the main reasons of these issues is the current design of the electrical grid, which is designed for centralized power production in big power plants from where the customers are served with electrical energy. In the case that one of these power plans has an outage, the impact is huge because it could affect several major cities or worse, e.g. the Northeast blackout of 2003. This paper proposes an approach to improve the stability of the electrical grid through decentralized networks and energy trading. The idea is to decrease the deviation from the schedule of the power plant operators and to create an economic incentive for homeowners. This is achieved by tradable goods, which are traded in such a network. This paper presents a model of a decentralized network, which consists of several smart houses with data taken from real consumers. The model or rather trading process is implemented with the multiagent framework JADE that allows implementing a distributed network with different type of participants. The trading process works in a way that a leader is elected in the beginning of the process. Once the leader is elected, all other participants inform the leader in short time intervals about their energy demands and their offers. An offer corresponding here to a tradable good such as receiving energy from a photovoltaic system, storing energy in a battery or switching on a boiler. In each interval, respectively cycle, the leader calculates the deviation from the schedule according to the schedule and the energy demands of the participants. When the deviation from the schedule is greater than zero, the leader looks for the best offers to decrease the deviation. Hereby, a participant gets paid when the leader accepts its offer. According to the findings and results in this thesis, it is feasible to improve the stability of the electrical grid and to create an economic incentive for homeowners. While smart houses with a battery help to reduce the deviation from the schedule immensely, introduce smart houses with a photovoltaic system fluctuation and therefore increase the deviation. On the other side, smart houses with a photovoltaic system get more profit than houses with a battery because the produced energy of photovoltaic system has to be used at any price. Although, this thesis shows that energy trading can improve the stability of the electrical grid and create an economic incentive for homeowners at the same time. A concrete business model is missing, which describes how such a decentralized network can be introduced and sold to homeowners. Furthermore the simplifications of the energy demand forecast function and the leader election in this thesis are to be considered.11 - Studentische ArbeitPublikation Variant Management for Software Applications for Public Administrations(Hochschule für Wirtschaft FHNW, 22.07.2016) Gryzlak, Karin; Hinkelmann, KnutNowadays, software is getting more complex due to upcoming requirements from customers. It is therefore necessary to handle the variants of a software system’s different components and to know what customer uses which component and/or variant. In the area of public administrations, the requirements differ as they are not just influenced by the needs of a company but also by laws and regulations. The purpose of variant management is to handle customer-specific parts for different customers within one system. In order to handle such variants, different concepts can be applied. However, although variant management can be used for every kind of software, it needs to be adapted to the specific case of software for public administrations. This research thesis illustrates how feature trees can be extended and adapted to represent the elements of the specific case of variant management for public administration software. The starting point are software product lines (SPL) with the concept of feature trees for describing a system. Adding elements like influencers or rules to the concept of feature trees and extending it with new relations such as requires shows that it is possible to model variants in an area with specific requirements. Modelling a system with the extended feature model allows finding and retrieving variants for individual customers. A model based on feature trees for an application used in public administrations with all relevant features and relations is developed. The investigated application is a message based register with data about residents on cantonal level. The development is based on results of interviews with employees of a company that develops software for public administrations. In order to evaluate the model, actual results of queries are compared to expected results. Queries are used to retrieve information from the modelled application based on a specific syntax. To find out if the approach could be applicable and useful in practice, some of the practitioners are consulted.11 - Studentische ArbeitPublikation Modelling Language for Domain-Specific Decisions in Healthcare(Hochschule für Wirtschaft FHNW, 20.02.2017) Sibold, Pascal; Hinkelmann, Knut11 - Studentische Arbeit