Knowledge Reuse Through Electronic Knowledge Repositories: An Empirical Study And Ontological Improvement Effort For The Manufacturing Industry

Knowledge management adoption is growing, and will continue to grow in no small part because of its recent inclusion into the ISO 9001 quality standard. As organizations look towards ways in which to manage their knowledge, the codification of explicit knowledge through Knowledge Management Systems (KMS) and Electronic Knowledge Repositories (EKRs) will undoubtedly gain more interest. An EKR is a form of KMS that emphasizes the codification and storage of organizational expertise for the purposes of Knowledge Reuse (KRU). Unfortunately, the factors surrounding KRU are not well understood. While previous studies have viewed EKR usage from a narrow perspective, a broader and interconnected view of KRU via EKRs has yet to emerge. Additionally, while there have been numerous benefits linked to EKRs, there are still issues that limit their utility, particularly in the manufacturing arena where information complexity and geography have made it increasingly difficult to share knowledge. Hence, this research employed a two pronged approach. First, using a multi-theoretical perspective to model KRU via EKRs, a quantitative study was conducted and identified several socio-technical factors that predicted greater KRU. These factors had not been previously modeled within the context of KRU via EKRs, and hence add to both the theoretical and practical implications of the domain. Additionally, the KRU construct was also tied to a back end resulting outcome view that was informed by the Expectation Confirmation Model (ECM). Through this view, the research quantitatively validated that KRU not only predicted greater performance, but also impacted greater knowledge sharing and continuance of use. This ancillary benefit helps to reinforce the importance of EKRs in that additional gains are manifested along with the core component of KRU. Second, the research extended the capability of manufacturing EKRs by developing a holistic design and process based ontology that connects key concepts within these domains to provide an overall interconnected view. Additionally, to ensure the relevance of the ontology, a mature and globally recognized industry standard was used as the basis to develop it. The ontology was then formalized and tested via Semantic Web tools: Protege, RDF, and SPARQL. The results demonstrate an improved approach to knowledge recall by providing rich and accurate query returns. The ability to use standalone and federated queries to effectively cull the complexity of this interconnected domain is an enhancement to keyword based and traditional relational database approaches. Additionally, to assist with greater industry adoption a systematic and constructive approach for developing and operationalizing the ontology is provided. Finally, in the spirit of the program in which this dissertation is presented, rounding out the research effort are broader organizational management recommendations for overall knowledge management. Referencing industry targeted literature and syncing them with findings from these two research efforts, several pragmatic and sequentially logical approaches to knowledge management are offered

Where I’m From: Internal Manifestations Among Cambodian Women Using The Expressive Arts A Literature Review

Chronic mental illness has affected many Cambodian people, but, culturally, Cambodians aren’t accustomed to opening up and discussing their feelings, rather defining mental illness to craziness and seeking help is presumed taboo. Thus, Cambodians are often reluctant to talk about their experiences and/or their related illnesses. Though Cambodians have experienced inconceivable suffering and violence during the Khmer Rouge era, for the purpose of this thesis, I will be discussing the role of Cambodian women and investigate the extent of what they’ve witnessed and experienced. Cambodian women have suffered through many years of trauma and grief, during and after the Khmer Rouge regime, but have yet to fully explore the root of their mental health issues. All trauma involves loss, whether it be loss of safety or security, world-view, or the loss of a person by death or other types of separation. Characteristics of grief tend to overlap with those of trauma experience. It is important to remember that the way people grieve and process that grief varies from one person to the next. One of the questions I am asking in this capstone thesis exploration is: Could it be that sometimes the brain’s way of protecting us is to block out painful memories to teach us how to survive. This literature review will be examined and organized into four parts: writings about Cambodian women, trauma, grief, expressive arts therapy and how it relates to this population. Existing research supports the benefits of using Expressive Arts Therapy with Cambodian women who are finding their way to not only cope, but to discover everlasting tools to bring about healing into their everyday lives

Ga^+ beam lithography for nanoscale silicon reactive ion etching

By using a dry etch chemistry which relies on the highly preferential etching of silicon, over that of gallium (Ga), we show resist-free fabrication of precision, high aspect ratio nanostructures and microstructures in silicon using a focused ion beam (FIB) and an inductively coupled plasma reactive ion etcher (ICP-RIE). Silicon etch masks are patterned via Ga^+ ion implantation in a FIB and then anisotropically etched in an ICP-RIE using fluorinated etch chemistries. We determine the critical areal density of the implanted Ga layer in silicon required to achieve a desired etch depth for both a Pseudo Bosch (SF_6/C_4F_8) and cryogenic fluorine (SF_6/O_2) silicon etching. High fidelity nanoscale structures down to 30 nm and high aspect ratio structures of 17:1 are demonstrated. Since etch masks may be patterned on uneven surfaces, we utilize this lithography to create multilayer structures in silicon. The linear selectivity versus implanted Ga density enables grayscale lithography. Limits on the ultimate resolution and selectivity of Ga lithography are also discussed

Investigating the relationship between negative relative accommodation recovery and high neutral retinoscopy

Negative Relative Accommodation (NRA) is a common subjective protocol used by many practitioners to assess a patient\u27s ability to reduce accommodation relative to a nearpoint vergence demand of 40 centimeters. High Neutral retinoscopy (HN) is an objective test that utilizes a similar procedural protocol and vergence demand, also to assess a patient\u27s ability to relax accommodation. During HN, excessive plus power is slowly decreased so that the patient must reduce accommodation in order to clear letters at a nearpoint distance of 50 centimeters. For reasons including examiner preference, difficulty of testing, confidence with endpoints or patient cooperation, HN is not a commonly utilized test. Although both NRA and HN assess how well a patient can actively release accommodation, HN requires the patient to clearly locate and identify letters alphabetically during the examination, adding a cognitive component. As a result, HN provides more of a real life (and arguably more practical) assessment of accommodative relaxation than NRA, and can provide valuable information in instances when a patient presents with problems that may be related to hyper-responsive accommodative. The purpose of this study is to determine if NRA recovery can confidently substitute for High Neutral retinoscopy when HN results are desired. Statistical analysis reveals an insignificant correlation between the net values of predicted versus actual HN net values (R=~ 0 .184) as determined by the equation -0.004076 1 (NRA recovery net) + 1.600883 15. From a clinical perspective, the errors of predicted HN to true HN results was within 0.37 diopters if specific clinical features were ruled out. The results of this study suggest that an examiner may elect to use a predicted HN net value based on the NRA recovery net value when only an approximation is desired, and only when latent hyperopia and a tendency for an accommodative lead under binocular conditions has been first ruled out

Using Risk-Tracing Snowball Approach to Increase HIV Case Detection Among High-Risk Populations in Cambodia: An Intervention Study

Background: Early HIV diagnosis and initiation onto antiretroviral therapy may prevent ongoing spread of HIV. Risk Tracing Snowball Approach (RTSA) has been shown to be effective in detecting new HIV cases in other settings. The main objective of this study is to evaluate the effectiveness of RTSA in increasing the rate of newly identified HIV cases among high-risk populations. Our second objective was to evaluate the effectiveness of RTSA, as compared to the walk-in group, in increasing the number of HIV tests and early case detection. Methods: This study was conducted from April 1 to September 30, 2016 at two NGO clinics in Phnom Penh, Cambodia. Respondent driven sampling method was adapted to develop RTSA to reach high-risk populations, including key populations and the general population who have social connections with key populations. Bivariate and multivariate logistic regression analyses were conducted. Results: During the implementation period, 721 clients walked in for HIV testing (walk-in group), and all were invited to be seeds. Of the invited clients, 36.6% agreed to serve as seeds. Throughout the implementation, 6195 coupons were distributed to seeds or recruiters, and resulted in 1572 clients visiting the two clinics with coupons (RTSA group), for a coupon return rate of 25.3%. The rate of newly identified HIV cases among the RTSA group was significantly lower compared to that in walk-in group. However, the highest number of newly identified HIV cases was found during the implementation period, compared to both pre- and post-implementation period. Although statistically not significant, the mean CD4 count of newly identified HIV cases detected through RTSA was almost 200 cells/mm3 higher than that in the walk-in group. Conclusions: Although the rate of newly identified HIV cases among the RTSA group was lower than that in the walk-in group, the inclusion of RTSA in addition to the traditional walk-in method boosted new HIV case detection in the two participating clinics. A higher mean CD4 count for the RTSA group may reveal that RTSA may be able to detect HIV cases earlier than the traditional walk-in approach. Further research is needed to understand whether RTSA is a cost-effective intervention to prevent ongoing spread of the HIV among high-risk populations in Cambodia

Applied Epidemiology in Cambodia.

In meeting the Master of Philosophy in Applied Epidemiology (MAE)'s, I completed two of my core projects at the Institute Pasteur of Cambodia (IPC), a non-governmental organization. The other two core projects I completed at the Ministry of Health's Cambodian Communicable Disease Control Department (CCDC), where I was later deployed to support Coronavirus Disease 2019 (COVID-19) contact tracing and surveillance. In this thesis, I demonstrate how I met the core competencies of the MAE program. In late November and early December 2019, a provincial health department notified CCDC about what they called a food poisoning event that had affected more than 200 people, and resulted in two deaths in a residential facility in a province of Cambodia. We conducted a case-control study. We found a strong association between eating cucumbers and illness. However, laboratory analysis failed to detect a causative agent. Toxicology testing was not conducted, and therefore we were unable to rule out contamination of the cucumbers. This project is described in chapter two, "An outbreak of unknown etiology associated with fresh cucumbers in a residential facility in Cambodia, 2019". We aimed at describing how malaria has evolved spatially from 2006 to 2019. We undertook a secondary analysis of existing malaria data from all public health facilities in Cambodia between 2006 and 2019 in combination with metadata. Overall, incidence fluctuated between 1.5 and 7.4 cases/1000 inhabitants per year. Malaria clusters were detected in seven northern provinces, along borders. We recommended that interventions aimed at preventing new infections of Plasmodium vivax and relapses should be prioritized. All confirmed malaria cases should be reported to Health Management Information System to avoid misleading trends. This project is detailed in chapter three, "Malaria in Cambodia: retrospective analysis of a changing epidemiology 2006-2019." I implemented and evaluated the RAI2 surveillance system as part of activities associated with a funded malaria project. Nine attributes, adapted from the US CDC guideline 2001, were used to assess the performance of the system. Usefulness was described based on the outcome of the evaluation of the other eight attributes. Simplicity, flexibility, acceptability, and stability were assessed using a short online survey with health center staff. Sensitivity, positive predictive value, data quality, and timeliness were assessed using document review and data from the RAI2 surveillance system. Findings suggested that the RAI2 surveillance system was simple, flexible, stable, timely but did not meet its primary objective. We recommended that the RAI2 surveillance system should be integrated into the national malaria information system and moved to be a real-time data collection. Additional exposure variables should be captured. I placed this project in chapter four, "Using Kobo Toolbox as a malaria project-based surveillance system in Cambodia: surveillance evaluation." My final project was to estimate the proportion of COVID-19 cases that were asymptomatic and understand how the asymptomatic transmission may occur. I analyzed data from 22 cases as part of a cluster of returned travelers, with what was believed to be a common exposure site. Their 491 uninfected contacts and ten infected contacts were also included in the analysis. The findings suggested asymptomatic cases made up a larger proportion of total cases within the cluster. This project is described in chapter five, "Coronavirus Disease 2019 asymptomatic transmission: A cluster review in Cambodia, 2020." Finally, other required activities presented in this thesis include an oral presentation, a scientific manuscript submitted to a peer-review journal, a literature review, a summary for a layperson, lessons learned from the field, and teaching

Effets d'additifs polymériques sur les cinétiques de précipitation de carbonate de calcium en présence de matières en suspension et de matériaux de corps d'échange thermique : applications aux circuits de refroidissement industriels

Ces travaux de thèse portent sur l’effet d’additifs polymériques sur les cinétiques de précipitation de carbonate de calcium en présence de matières en suspension (MES) et de surfaces de matériaux représentatifs des corps d’échange thermique mis en oeuvre dans les circuits de refroidissement industriels (CRF). Pour mener cette étude à l’échelle du laboratoire un dispositif à composition constante est mis au point pour reproduire les conditions d’exploitation d’un CRF. En absence d’inhibiteur, la vitesse de croissance des cristaux de CaCO3 augmente avec l’augmentation de la concentration en MES dans l’eau circulant dans le CRF. Dans la gamme de températures opérationnelles du CRF, la vitesse de croissance cristalline augmente avec l’augmentation de la température. La performance d’inhibition de la croissance des cristaux deCaCO3 de cinq additifs, en présence de semences de calcite est évaluée. L’homopolymère acrylique (HA) appartenant à la famille des additifs « conventionnels » et l’acide polyaspartique (PASP) de la famille des additifs « verts » présentent les meilleures performances. Le taux d’inhibition décroît avec l’augmentation de la température. Sur les cinq additifs, quatre sont des inhibiteurs de la croissance (acide citrique, HA, copolymère carboxylique, PASP) et un est un inhibiteur de la nucléation (acide polyépoxysuccinique PESA). L’utilisation d’un mélange d’inhibiteur de nucléation (PESA) et d’un inhibiteur de croissance, en particulier le PASP, a permis de rallonger le temps de latence apparent de la croissance de CaCO3 (supérieur à 18 heures) temps que l’on peut comparer au temps de séjour de l’eau dans un CRF, tout en assurant un taux d’inhibition de la croissance de 85 à 89 %. Le temps de latence apparent augmente avec l’augmentation de la concentration en PESA dans le mélange. L’inhibition de la croissance résulte de l’adsorption des molécules d’additif polymérique sur les sites de de croissance des cristaux suivant le modèle d’adsorption de Langmuir. Les matériaux PVC constitutifs de corps d’échange thermique mis en contact avec la solution sursaturée en présence de semences de calcite conduisent également à des vitesses de croissance cristalline supérieures à celle observée sur les semences de calcite. La présence d’additif polymérique HA a permis d’inhiber la croissance cristalline sur la surface du PVC d’environ 90 %. L’inhibition de la croissance cristalline sur la surface du PVC résulte également de l’adsorption des molécules d’additif sur les sites actifs. A l’échelle industrielle, des essais ont été menés sur des installations pilotes dans des conditions similaires à celles utilisées en laboratoire. Les résultats ont été simulés à l’aide du logiciel CooliSS (Cooling circuit Simulation Software) développé par EDF R&D en utilisant une loi locale d’inhibition, proposée à partir des données locales acquises en laboratoire et des mesures de dépôt sur des coupons de matériaux introduits dans les pilotes à différents endroits du circuit. Les facteurs d’efficacité de l’additif polymérique dépendent de la nature de matériau (Inox et PVC) et de la présence de MES dans le CRF. Une meilleure corrélation entre les résultats expérimentaux obtenus sur les installations pilotes et ceux simulés par le logiciel CooliSS est obtenue pour des facteurs d’efficacité respectifs de 0,753 pour le matériau d’inox (condenseur) et 0,785 pour le matériau PVC (garnissage dans le réfrigérant atmosphérique). Cependant, les améliorations de la sensibilité de la simulation restent à apporter en agissant sur la relation entre ces facteurs d’efficacité et la concentration en ME

Mobilité géographique des étudiants en médecine ayant choisi la médecine générale à l'issue des épreuves classantes nationales : description et déterminants du choix de la subdivision

After the national ranking exam, medical students have the possibility to move geographically with the choice of subdivision. The objective was to analyze the future general practitioner trainees’ geographic mobility depending on the characteristics of the students on one hand and of the subdivisions on the other. Specifying the logic governing these choices seemed important in the current demographic context of general practice. The studied population (n=9274) consisted of all students (ministry’s database) who have chosen general practice discipline from the national ranking exams from 2004 to 2009. Several groups were defined according to the type of migration: the groups "chosen migration" and "forced migration" depending on the student’s ranking position, if it allows him to stay within his initial subdivision or not ; and the group "no migration". These groups have been compared for each year, according to 15 variables characterizing students (gender, adjacency with the new subdivision...) and subdivisions (hours of sunshine, density of general practitioners, migration, economic indicators...) using mixed models with a random intercept. Mobility affected 38% of students. The most attractive subdivisions were those in southern of France and Paris. Every year, two variables have significantly impacted the two migrations "chosen" and "forced": sunshine and density of GPs. In choosing their subdivision, future GPs favored an heliotropic logic that accentuates the current imbalances in medical demography.À l'issue des épreuves classantes nationales (ECN), les étudiants de médecine ont une occasion de mobilité géographique par le choix de leur subdivision d’internat. Notre objectif était d’analyser cette mobilité chez les futurs internes de médecine générale en fonction des caractéristiques, d’une part des étudiants, et d’autre part des subdivisions. Préciser les logiques qui président à ces choix paraissait important dans le contexte démographique actuel de la médecine générale. La population analysée (n=9274) est l’ensemble des étudiants (base du ministère) ayant choisi la discipline médecine générale à l'issue des ECN de 2004 à 2009. Plusieurs groupes ont été définis selon leur type de migration : les groupes "migration choisie" et "migration forcée" selon que l’étudiant a un rang de classement lui permettant de rester dans sa subdivision d’origine ou pas ; et le groupe "absence de migration". Ces groupes ont été comparés pour chaque année, selon 15 variables caractérisant les étudiants (sexe, proximité de la nouvelle subdivision…) et les subdivisions (ensoleillement, densité de médecins généralistes, solde migratoire, indicateurs économiques…) à l'aide de modèles mixtes à intercept aléatoire. La mobilité a concerné 38% des étudiants. Les subdivisions les plus attractives ont été celles du sud et Paris. Chaque année, deux variables ont distingué de manière significative les deux migrations "choisies" et "forcées" : l'ensoleillement et la densité de médecins généralistes. Dans le choix de leur subdivision, les futurs généralistes privilégient une logique héliotrope qui accentue les déséquilibres actuels de la démographie médicale

On the Spectral Behavior and Normalization of a Resonance-Free and High-Frequency Stable Integral Equation

The combined field integral equation (CFIE) used for solving scattering and radiation problems, although a resonance-free formulation, suffers from an ill-conditioning that strongly depends on the frequency and discretization density, both in the low- and high-frequency regime, resulting in slow convergence rates for iterative solvers. This work presents a new preconditioning scheme for the CFIE that cures the low-and the high-frequency as well as the dense discretization breakdown. The new preconditioner for the CFIE is based on a spherical harmonics analysis and the proper regularization with Helmholtz-type operators. Numerical results have been obtained to prove the effectiveness of this new formulation in real scenarios