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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Entzug als Endlosschleife?: die Rolle von Sozialarbeitern und Sozialarbeiterinnen bei Entstehung und Vermeidung emotionaler Abhängigkeiten im Suchthilfekontext

Dietze, Claudia 26 January 2024 (has links)
Die Masterarbeit beleuchtet die Entstehung emotionaler Abhängigkeitsverhältnisse zwischen Fachkräften der Sozialen Arbeit im Bereich der Suchtkrankenhilfe und ihren Adressaten. Besonders im Suchthilfebereich sind (anderweitige) Abhängigkeiten als höchst vulnerabel anzusehen, da sie das „Prinzip“ Hilfe zur Selbsthilfe massiv stören und den „Suchtkreislauf“ nicht durchbrechen, sondern (auf anderer Ebene) erhalten können. Ziel der Arbeit ist es, durch Befragung von Fachkräften in unterschiedlichen Einrichtungen das professionsbezogene Bewusstsein menschlicher und kontextueller Abhängigkeiten zu ergründen und Perspektiven wie Möglichkeiten zu sammeln, wie diese Abhängigkeitsverhältnisse abgebaut oder verhindert werden können.:Vorwort 2 Tabellenverzeichnis 5 Einleitung 6 1 Vorangegangenes Praxisforschungsprojekt 8 1.1 Kurzvorstellung 8 1.2 Reaktionen aus der Praxis 10 2 Der theoretische Raum – Zentrale Begriffe 12 2.1 Die (professionelle) Beziehung 12 2.2 Nähe und Distanz 19 2.3 Emotionen und emotionale Abhängigkeit 21 2.4 Empowerment und Ressourcen 25 3 Der praktische Raum – Kontexte Sozialer Arbeit in der Suchthilfe 29 3.1 Das Fachkrankenhaus für Psychiatrie und Psychotherapie 29 3.2 Die Rehabilitationsklinik 33 3.3 Die Adaption/Nachsorge 36 3.4 Die suchtmedizinische Tagesklinik 37 3.5 Die Suchtberatungs- und Behandlungsstelle 39 4 Forschungsdesign 42 4.1 Forschungsfrage, Zielgruppe und Ziel 42 4.2 Aktueller Forschungsstand, Methodik und Feldzugang 43 4.3 Entwicklung des Erhebungsinstruments 45 5 Forschungsdurchführung 49 5.1 Pretest 49 5.2 Durchführung der Interviews 50 5.2.1 Adaption/Nachsorge 50 5.2.2 Psychiatrisches Fachkrankenhaus 51 5.2.3 Rehabilitationsklinik 51 5.2.4 Suchtberatungs- und Behandlungsstelle 52 5.2.5 Suchtmedizinische Tagesklinik 53 5.3 Nachbereitung und Transkription der Interviews 54 5.4 Ressourcen und Herausforderungen 55 6 Der Auswertungsprozess 57 6.1 Vorstellung der Auswertungsmethode 57 6.2 Auswertung der Interviews 58 6.2.1 Interview I: Adaption/Nachsorge 58 6.2.2 Interview II: Psychiatrisches Fachkrankenhaus 66 6.2.3 Interview III: Rehabilitationsklinik 75 6.2.4 Interview IV: Suchtberatungs- und Behandlungsstelle I 82 6.2.5 Interview V: Suchtberatungs- und Behandlungsstelle II 89 6.2.6 (schriftliches) Interview VI: stationäre Entzugsbehandlung 99 6.3 Diskussion der Ergebnisse mit Rückbezug auf die Praxis 101 7 Abschluss 110 7.1 Offene Forschungsfragen mit Ausblick 110 7.2 Zusammenfassung und Fazit 112 Eidesstattliche Erklärung 113 Literaturverzeichnis 114 Anlagenverzeichnis 121
2

Über die Bedeutung queersensibler Suchtberatung: Diskussion am Beispiel zweier ausgewählter Konzeptionen

Zaun, Maike 22 November 2024 (has links)
Das Ziel dieser Bachelorarbeit ist es, auf Grundlage einer Literaturrecherche den Zusammenhang der beiden Themenkomplexe Queerness und Sucht darzustellen. Einführend werden beide Themen einzeln beleuchtet, um ein einheitliches Ver-ständnis beider Begrifflichkeiten zu schaffen. Auf dieser Basis werden sie im späte-ren Verlauf miteinander verknüpft und es wird dargestellt, inwiefern queere Perso-nen von Sucht bzw. Abhängigkeit betroffen sind. Als Erklärungsansatz wird das Mi-noritätenstressmodell aufgeführt und erläutert. Es werden Studien hinzugezogen, die die erhöhte Häufigkeit von Substanzkonsum und -abhängigkeit bei Queers be-legen und herausgearbeitet, auf welches Zusammenspiel verschiedener Stressoren und Belastungen dies zurückzuführen ist. Davon ausgehend wird abgeleitet, weshalb Queersensibilität innerhalb von Suchtberatungskontexten bedeutsam und notwendig ist. Es werden Kategorien und Indikatoren zu Queersensibilität erarbeitet, die auf institutioneller Ebene wirken und durch die Verankerung in Konzeptionen ihre Wirkung entfalten. Auf dieser Basis werden zwei exemplarische Konzeptionen von Suchtberatungsstellen analysiert, um einen Ist-Zustand zu ermitteln und Möglichkeiten und Grenzen der Berücksichtigung von Queersensibilität zu diskutieren. Bei dieser Arbeit handelt es sich um den Versuch, bei einer noch begrenzten Forschungslage zur Schnittstelle beider Themenbereiche, diese in ihrer Komplexität und Kausalität in Zusammenhang zu setzen. Gleichzeitig soll ein Anreiz für die Weiterentwicklung einer queersensiblen Sozialen Arbeit im Suchtberatungskontext und für weiterführende Forschung gesetzt werden.:1 Einleitung 2 Theoretische Grundlagen im Kontext von Queerness 2.1 Annäherung an den Begriff Queer 2.2 Queersensibilität in einer cis- und heteronormativen Gesellschaft 2.3 Besondere Belastungen von Queers 3 Theoretische Grundlagen im Kontext von Sucht 3.1 Annäherung an den Begriff Sucht 3.2 Ausgewählte Modelle zur Suchtentstehung 3.3 Einordnung der Suchtberatung in das Suchthilfesystem 3.4 Kritische Betrachtung von Sucht und Suchthilfe 4 Über den Zusammenhang von Queerness und Sucht 4.1 Einblick in die aktuelle Forschungslage 4.2 Das Minoritätenstressmodell als Erklärungsansatz 5 Queersensibilität auf institutioneller Ebene 5.1 Die institutionelle Ebene 5.2 Die Konzeption als Instrument der institutionellen Ebene 5.3 Queersensibilität in Konzeptionen 6 Analyse und Diskussion von zwei ausgewählten Konzeptionen 7 Fazit und Ausblick
3

Managing Service Dependencies in Service Compositions

Winkler, Matthias 21 December 2010 (has links) (PDF)
In the Internet of Services (IoS) providers and consumers of services engage in business interactions on service marketplaces. Provisioning and consumption of services are regulated by service level agreements (SLA), which are negotiated between providers and consumers. Trading composite services requires the providers to manage the SLAs that are negotiated with the providers of atomic services and the consumers of the composition. The management of SLAs involves the negotiation and renegotiation of SLAs as well as their monitoring during service provisioning. The complexity of this task arises due to the fact that dependencies exist between the different services in a composition. Dependencies between services occur because the complex task of a composition is distributed between atomic services. Thus, the successful provisioning of the composite service depends on its atomic building blocks. At the same time, atomic services depend on other atomic services, e.g. because of data or resource requirements, or time relationships. These dependencies need to be considered for the management of composite service SLAs. This thesis aims at developing a management approach for dependencies between services in service compositions to support SLA management. Information about service dependencies is not explicitly available. Instead it is implicitly contained in the workflow description of a composite service, the negotiated SLAs of the composite service, and as application domain knowledge of experts, which makes the handling of this information more complex. Thus, the dependency management approach needs to capture this dependency information in an explicit way. The dependency information is then used to support SLA management in three ways. First of all dependency information is used during SLA negotiation the to ensure that the different SLAs enable the successful collaboration of the services to achieve the composite service goal. Secondly, during SLA renegotiation dependency information is used to determine which effects the renegotiation has on other SLAs. Finally, dependency information is used during SLA monitoring to determine the effects of detected violations on other services. Based on a literature study and two use cases from the logistics and healthcare domains different types of dependencies were analyzed and classified. The results from this analysis were used as a basis for the development of an approach to analyze and represent dependency information according to the different dependency properties. Furthermore, a lifecycle and architecture for managing dependency information was developed. In an iterative approach the different artifacts were implemented, tested based on two use cases, and refined according to the test results Finally, the prototype was evaluated with regard to detailed test cases and performance measurements were executed. The resulting dependency management approach has four main contributions. Firstly, it represents a holistic approach for managing service dependencies with regard to composite SLA management. It extends existing work by supporting the handling of dependencies between atomic services as well as atomic and composite services at design time and during service provisioning. Secondly, a semi-automatic approach to capturing dependency information is provided. It helps to achieve a higher degree of automation as compared to other approaches. Thirdly, a metamodel for representing dependency information for SLA management is shown. Dependency information is kept separately from SLA information to achieve a better separation of concerns. This facilitates the utilization of the dependency management functionality with different SLA management approaches. Fourthly, a dependency management architecture is presented. The design of the architecture ensures that the components can be integrated with different SLA management approaches. The test case based evaluation of the dependency management approach showed its feasibility and correct functioning in two different application domains. Furthermore, the performance evaluation showed that the automated dependency management tasks are executed within the range of milliseconds for both use cases. The dependency management approach is suited to support the different SLA management tasks. It supports the work of composite service providers by facilitating the SLA management of complex service compositions.
4

Double Threat - Trauma and PTSD in Adolescents with Substance Use Disorders

Basedow, Lukas Andreas 05 October 2022 (has links)
Background: Substance use disorders (SUDs) are a great burden on adolescent patients and treatment of these patients is often not successful. One reason for this difficulty is the high rate of co-occurring disorders. One disorder that frequently accompanies SUDs in adolescence is a Post-Traumatic Stress Disorder (PTSD). In studies it has often been reported that a large number of patients fulfill diagnostic criteria for both disorders at the same time. Several explanations for this co-occurrence exist: i) A common etiological factor (genetic predisposition, similar neurobiological pathways) might underlie the development of both disorders. ii) Various lifestyle factors that go hand-in-hand with an adolescent SUD (risky sexual behavior, violent dark markets) might expose patients to circumstances that increase the rate of encountered traumatic experiences (TEs) and therefore PTSD. iii) The self-medication hypothesis, where it is posited that adolescents use drugs to medicate their PTSD symptoms, often in a very specific manner, such that particular substances are used to reduce explicit symptoms. One aim explored in this thesis is the relationship between SUD, TEs, and PTSD with regard to differences in SUD severity, patterns of substance use, the role of self-medication and the effects of SUD-specific treatment on PTSD symptomatology. Methods: Five studies are presented in chapters 2 to 6 of this thesis. Chapter 2 contains a study in which the Drug Use Disorder Identification Test (DUDIT) was evaluated for use in a psychiatric adolescent patient population. This was the first study in which the DUDIT in relation to DSM-5 criteria was evaluated, in order to try to establish cut-off scores for the presence of a SUD in adolescents. In chapter 3 an evaluation is presented of the differences in SUD severity between adolescents with a SUD (‘noTE’ group), adolescents with a SUD and a history of TE but not PTSD (‘TE’ group) and adolescents with SUD and co-occurring PTSD (‘PTSD’ group). In the study presented in chapter 4 an investigation of the differences in substance use patterns between the three groups was undertaken, along with an evaluation of the associations between PTSD symptoms and use of specific substances. In chapter 5, the role coping motives play in the relationship between substance and PTSD symptoms was established. Finally, in chapter 6 the results of a pragmatic clinical trial are presented, in which the effects of a group-based treatment manual (the DELTA program) on SUD symptoms, substance use frequency and PTSD symptoms are assessed. Results: Across all included studies in this dissertation, an instrument for the assessment of SUD in adolescents was evaluated. This was used with other instruments, to establish a link between adolescent SUD and increased rates of PTSD and substance use. Furthermore, the connection between SUD and PTSD in adolescence seems to be related to a self-medication motive. Additionally we established a treatment program that reduced SUD symptoms but failed to influence the PTSD symptoms, which indicates treatment specific to one disorder is unlikely to support reductions in the co-occurring disorder. More specifically, the results presented in chapter 2 showed that the DUDIT has excellent discriminant validity and is a valid tool for the assessment of SUD severity in a clinical adolescent population. In chapter 3, it was shown that the prevalence of TEs and PTSD in adolescents with SUD is higher than in the general adolescent population. Furthermore, the PTSD group showed a significantly higher level of SUD severity than the other two groups. In contrast to our expectations, the TE group did not differ significantly with regard to SUD severity from the noTE group. In addition, SUD severity correlated positively with the number of PTSD symptoms in each symptom cluster. The study presented in chapter 4 showed that past-month substance use frequency was nearly the same across groups and across substances, with only the use of methylenedioxymethamphetamine (MDMA) being significantly more frequent and more prominent in the PTSD group compared to the other two. Participants in the PTSD group also reported a significantly earlier age of first substance use compared to participants in the other two groups. Moreover, in this study it was shown that the presence of the avoidance symptom cluster of PTSD was related to a more frequent past-month MDMA use. The findings presented in chapter 5, confirmed the pattern detected for past-month substance use in chapter 4. The PTSD group showed a more frequent MDMA use over the past-year compared to the other two groups. Additionally, the PTSD group reported using substances more frequently for coping reasons, and the frequency of coping use motives was positively correlated with the frequency of past-year MDMA use. In this study, evidence was provided that the relationship between group membership (noTE, TE, PTSD) and MDMA use frequency is in part mediated by the relationship both variables have with coping use motives. In chapter 6 medium-sized but non-significant reductions were shown in SUD symptoms and substance use frequency as a result of the DELTA intervention. Additionally, there was no indication that the treatment program resulted in changes in PTSD symptomatology. Discussion: Several important conclusion can be derived from the studies presented in this thesis. First, a co-occurring PTSD is more prevalent in SUD patients than in the general adolescent population and is associated with higher SUD severity. Second, patients with co-occurring PTSD and SUD are distinguished from SUD patients without PTSD through their increased use of MDMA. Third, the relationship between PTSD and MDMA use is partially mediated by a coping motive, supporting the self-medication hypothesis. Finally, the treatment of co-occurring PTSD and SUD seems to require therapeutic interventions specific for each disorder. The result that PTSD symptoms are not reduced after SUD-specific treatment can be interpreted as support for the self-medication hypothesis as well, in the sense that the treatment of the consequence (SUD) does not affect the preceding factor (PTSD). However, while the above interpretation is consistent with the data presented in this thesis on substance use itself, the associated data on the occurrence of SUDs indicates, that more factors than just self-medication are relevant for the development of a SUD. Furthermore, the results of this thesis do not imply that substance use motivated by self-medication motives is harmless or even beneficial, since there was no way of assessing if self-reported, coping-motivated substance use is successful in reducing symptoms or acute psychopathology. Consequently, in future projects focus should be on developing longitudinal research designs, in order to assess if and how PTSD symptoms develop over time with regard to substance use and how substance use trajectories develop in relation to PTSD symptomatology.
5

Description Logics with Concrete Domains and Functional Dependencies

Lutz, Carsten, Miličić, Maja 31 May 2022 (has links)
Description Logics (DLs) with concrete domains are a useful tool in many applications. To further enhance the expressive power of such DLs, it has been proposed to add database-style key constraints. Up to now, however, only uniqueness constraints have been considered in this context, thus neglecting the second fundamental family of key constraints: functional dependencies. In this paper, we consider the basic DL with concrete domains ALC(D), extend it with functional dependencies, and analyze the impact of this extension on the decidability and complexity of reasoning. Though intuitively the expressivity of functional dependencies seems weaker than that of uniqueness constraints, we are able to show that the former have a similarly severe impact on the computational properties: reasoning is undecidable in the general case, and NExpTime-complete in some slightly restricted variants of our logic.
6

Prevalence of Use, Abuse and Dependence of Illicit Drugs among Adolescents and Young Adults in a Community Sample

Perkonigg, Axel, Lieb, Roselind, Wittchen, Hans-Ulrich 03 December 2012 (has links) (PDF)
Prevalence findings for 1995 of illicit drug use as well as DSM-IV abuse and dependence are reported from a representative population sample of 3,021 respondents from Munich, Germany, aged 14–24 years. Results are based on personal interviews using the M-Composite International Diagnostic Interview (M-CIDI) with its DSM-IV diagnostic algorithms. Findings indicate that more than 30% of the adolescents and young adults are or have been using one or more illicit drugs at least once in their life. Men were slightly more likely to ever use drugs and used them more frequently than women. Cannabinoids were by far the most frequently used type of drug, followed by various stimulating drugs and hallucinogens. There is also considerable polysubstance use among 14- to 24-year-olds. Criteria for DSM-IV abuse without dependence were met by 4.1% of all men and 1.8% of all women, a dependence syndrome of any type of illicit drug was diagnosed in 2.5% of the men and 1.6% of the women. Cumulative age of onset incidence analyses suggest that substance use starts early, in about one-third before the age of 16 years and continues to rise for most drugs throughout adolescence and young adulthood. Overall these findings suggest that substance use and substance disorders are more prevalent than suggested in most previous German studies.
7

The natural course of cannabis use, abuse and dependence over four years: a longitudinal community study of adolescents and young adults

Sydow, Kirsten von, Lieb, Roselind, Höfler, Michael, Sonntag, Holger, Wittchen, Hans-Ulrich 05 April 2013 (has links) (PDF)
Objectives: To determine incidence and patterns of natural course of cannabis use and disorders as well as cohort effects in a community sample of adolescents and young adults. Method: Cumulative incidence and patterns of cannabis use and disorders were examined in a prospective longitudinal design (mean follow-up period=42 months) in a representative sample (N=2446) aged 14–24 years at the outset of the study. Patterns of cannabis use, abuse and dependence (DSM-IV) were assessed with the Composite International Diagnostic Interview (M-CIDI). Results: (1) Cumulative lifetime incidence for cannabis use (at second follow-up): 47%; 5.5% for cannabis abuse, 2.2% for dependence. (2) Men used and abused cannabis more often than women. (3) The majority of the older participants (18–24 years at baseline) had reduced their cannabis use at follow-up, while younger participants (14–17 years at baseline) more often had increased their use and developed abuse or dependence. (4) The younger birth cohort (1977–1981) tended to start earlier with substance (ab)use compared to the older birth cohort (1970–1977). (5) Cannabis use was associated with increasing rates of concomitant use of other licit and illicit drugs. Conclusions: Cannabis use is widespread in our sample, but the probability of developing cannabis abuse or dependence is relatively low (8%). The natural course of cannabis use is quite variable: about half of all cannabis users stopped their use spontaneously in their twenties, others report occasional or more frequent use of cannabis.
8

Wie stabil sind Drogenkonsum und das Auftreten klinisch-diagnostisch relevanter Mißbrauchs- und Abhängigkeitsstadien bei Jugendlichen? / Stability of cannabis use, abuse and dependence patterns in a community sample of adolescents

Wittchen, Hans-Ulrich, Höfler, Michael, Perkonigg, Axel, Sonntag, Holger, Lieb, Roselind 23 October 2012 (has links) (PDF)
Anhand einer prospektiven epidemiologischen Verlaufsstudie an einer repräsentativen Bevölkerungsstichprobe von ursprünglich 14- bis 17jährigen Jugendlichen (N=1395) werden die Häufigkeit und die Verlaufsmuster des Konsums, des Mißbrauchs und der Abhängigkeit von Cannabis untersucht. Die Jugendlichen wurden persönlich mit Hilfe eines Interviews befragt, wobei als diagnostisches Instrument das M-CIDI mit seinen DSM-IV Algorithmen verwendet wurde. Die Ergebnisse aus der Basiserhebung ergaben, daß 1995 etwa 20% aller 14- bis 17jährigen - in der Mehrzahl wiederholt - Cannabis probiert hatten und 6% der Population einen regelmäßigen Gebrauch aufweisen. Die Einjahres-Inzidenz (= Auftreten neuer Fälle) für den Cannabisgebrauch der nun 15- bis 19jährigen betrug zum Zeitpunkt der Nachuntersuchung 20,1% für die Männer und 16,3% für die Frauen. Für den regelmäßigen Gebrauch wurden Inzidenzraen von 12% (Männer) und 8,4% (Frauen) ermittelt. Die Stabilität des Konsumverhaltens zwischen der Basis- und der Nachuntersuchung war relativ hoch un stieg mit höherem Initialkonsum an. Angesichts der hohen Gebrauchsrate von 32,4% bei den 15- bis 19jährigen bei der Nachuntersuchung ergab sich im Vergleich zu anderen psychotropen Substanzen eine relativ niedrige Prävalenz für Mißbrauch und Abhängigkeit (4%). Das Vorliegen einer Diagnose bei der Erstuntersuchung weist allerdings eine relativ hohe Stabilität über die Nachuntersuchungskette auf. / The paper examines the prevalence, incidence and stability patterns of cannabis use and dependence in a prospective epidemiological study of a random community sample of adolescents, aged 14 to 17 years (N=1395) at time 1. Assesments are based on personal interviews by trained clinical psychologists using the computerized DSM-IV lifetime and 12-month change version of the M-CIDI. Results indicate that in 1995 every fifth person aged 14 to 17 years had used cannabis at least once and 6% reported regular use. The 12-month incidence rates (i.e. proportion of the sample reporting first cannabis use in the last year) among subjects, 15 to 19 years of age at time 2, was high, with 20,1% of males and 16,3% of females reporting first use. The incidence of regular use was 12,0% (males) and 8,4% (females). The stability of consumption patterns from time 1 to time 2 was high. Increasing with higher initial consumption. Given the reexamined samples overall high cannabis consumption rates of 32,4%, the prevalence of clinically manifest DSM-IV abuse and dependence was low in comparison to other psychologic drugs (4%). However there was remarkable diagnostic stability over time in this age group of those with an initial diagnosis at time 1 receiving a diagnosis again at time 2.
9

Feasibility and outcome of substitution treatment of heroin-dependent patients in specialized substitution centers and primary care facilities in Germany: A naturalistic study in 2694 patients

Wittchen, Hans-Ulrich, Apelt, Sabine M., Soyka, Michael, Gastpar, Markus, Backmund, Markus, Gölz, Jörg, Kraus, Michael R., Tretter, Felix, Schäfer, Martin, Siegert, Jens, Scherbaum, Norbert, Rehm, Jürgen, Bühringer, Gerhard 11 April 2013 (has links) (PDF)
Background: In many countries, buprenorphine and methadone are licensed for the maintenance treatment (MT) of opioid dependence. Despite many short-term studies, little is known about the long-term (12-month) effects of these treatments in different settings, i.e. primary care-based (PMC) and specialized substitution centers (SSCs). Objectives: To describe over a period of 12 months: (1) mortality, retention and abstinence rates; (2) changes in concomitant drug use, somatic and mental health; and (3) to explore differences between different types of provider settings. Methods: 12-Month prospective-longitudinal naturalistic study with four waves of assessment in a prevalence sample of N= 2694 maintenance patients, recruited from a nationally representative sample of N= 223 substitution physicians. Results: The 12-month retention rate was 75%; the mortality rate 1.1%. 4.1% of patients became “abstinent” during follow-up. 7% were referred to drug-free addiction treatment. Concomitant drug use decreased and somatic health status improved. No significant improvements were observed for mental health and quality of life. When controlling for initial severity, small PMC settings revealed better retention, abstinence and concomitant drug use rates. Conclusion: The study underlines the overall 12-month effectiveness of various forms of agonist MT. Findings reveal relatively high retention rates, low mortality rates, and improvements in most 12-month outcome domains, except for mental health and quality of life. PMC settings appear to be a good additional option to improve access to MTs.
10

Advancing the discovery of unique column combinations

Abedjan, Ziawasch, Naumann, Felix January 2011 (has links)
Unique column combinations of a relational database table are sets of columns that contain only unique values. Discovering such combinations is a fundamental research problem and has many different data management and knowledge discovery applications. Existing discovery algorithms are either brute force or have a high memory load and can thus be applied only to small datasets or samples. In this paper, the wellknown GORDIAN algorithm and "Apriori-based" algorithms are compared and analyzed for further optimization. We greatly improve the Apriori algorithms through efficient candidate generation and statistics-based pruning methods. A hybrid solution HCAGORDIAN combines the advantages of GORDIAN and our new algorithm HCA, and it significantly outperforms all previous work in many situations. / Unique-Spaltenkombinationen sind Spaltenkombinationen einer Datenbanktabelle, die nur einzigartige Werte beinhalten. Das Finden von Unique-Spaltenkombinationen spielt sowohl eine wichtige Rolle im Bereich der Grundlagenforschung von Informationssystemen als auch in Anwendungsgebieten wie dem Datenmanagement und der Erkenntnisgewinnung aus Datenbeständen. Vorhandene Algorithmen, die dieses Problem angehen, sind entweder Brute-Force oder benötigen zu viel Hauptspeicher. Deshalb können diese Algorithmen nur auf kleine Datenmengen angewendet werden. In dieser Arbeit werden der bekannte GORDIAN-Algorithmus und Apriori-basierte Algorithmen zum Zwecke weiterer Optimierung analysiert. Wir verbessern die Apriori Algorithmen durch eine effiziente Kandidatengenerierung und Heuristikbasierten Kandidatenfilter. Eine Hybride Lösung, HCA-GORDIAN, kombiniert die Vorteile von GORDIAN und unserem neuen Algorithmus HCA, welche die bisherigen Algorithmen hinsichtlich der Effizienz in vielen Situationen übertrifft.

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