Elements for Response Time Statistics in ERP Transaction Systems

We present some measurements and ideas for response time statistics in ERP systems. It is shown that the response time distribution of a given transaction in a given system is generically a log-normal distribution or, in some situations, a sum of two or more log-normal distributions. We present some arguments for this form of the distribution based on heuristic rules for response times, and we show data from performance measurements in actual systems to support the log-normal form. Deviations of the log-normal form can often be traced back to performance problems in the system. Consequences for the interpretation of response time data and for service level agreements are discussed.Comment: revtex, twocolumn, 8 pages, 13 figures. figures replaced by coloured version

On (In)security: A conversation on education and intergenerational dialogues

This paper presents a Q&A conversation held at the Performance Philosophy Biennial in Amsterdam, 2019. Three presentations responded to the conference call of ‘intervening in the habit of academia as a place for mature or adult voices,’ by exploring ways of making space for children’s voices. Connected by a focus on intergeneration dialogues, children’s disruption and the possibilities of empowerment, both within education and within familial structures, the three presentations opened a discussion about interpellation, sensitivity and (in)security. This paper presents this discussion in a reworked and extended format, offering insight into the presentations on the day, the subsequent conversation and the overarching questions that these dialogues provoke

A Importância das relações interpessoais na escola: alicerce para uma gestão democrática

This article addresses the importance of interpersonal relationships for school management. Considering that the manager's activity is not developed alone, but in a team, with the involvement of several people, it is necessary that the techniques of interpersonal relationships be used as a tool in the school environment. We carried out a qualitative, descriptive field research, using direct observation in an educational environment in two state schools in the municipality of Sobral - CE. Where the subjects were the teachers and directors of the mentioned schools. Finally, it was found that the knowledge of interpersonal relationships is an important factor in the manager's performance to perform his activities well, since it will help him to control his emotions in interpersonal relationships within the group he coordinates, favoring the production a good working environment, a fact that encourages those who are led, generating positive and productive results.Este artigo aborda a importância das relações interpessoais para a gestão escolar. Considerando que a atividade do gestor não se desenvolve de modo solitário, mas em equipe, com o envolvimento de diversas pessoas, é necessário que as técnicas das relações interpessoais sejam utilizadas como ferramenta no ambiente escolar. Realizamos uma pesquisa de campo, tipo qualitativo, descritivo, utilizando-se da observação direta em ambiente educacional em duas escolas estaduais do município de Sobral - CE. Onde os sujeitos foram os professores e diretores das escolas mencionadas. Constatou-se, por fim, que o conhecimento das relações interpessoais é fator importante na atuação do gestor para exercer bem suas atividades, uma vez que irá ajudá-lo no controle de suas emoções nas relações interpessoais dentro do grupo que coordena, favorecendo a produção de bom ambiente de trabalho, fato este que incentiva os liderados gerando resultados positivos e produtivos

Efficient iPS Cell Production with the MyoD Transactivation Domain in Serum-Free Culture

A major difficulty of producing induced pluripotent stem cells (iPSCs) has been the low efficiency of reprogramming differentiated cells into pluripotent cells. We previously showed that 5% of mouse embryonic fibroblasts (MEFs) were reprogrammed into iPSCs when they were transduced with a fusion gene composed of Oct4 and the transactivation domain of MyoD (called M3O), along with Sox2, Klf4 and c-Myc (SKM). In addition, M3O facilitated chromatin remodeling of pluripotency genes in the majority of transduced MEFs, including cells that did not become iPSCs. These observations suggested the possibility that more than 5% of cells had acquired the ability to become iPSCs given more favorable culture conditions. Here, we raised the efficiency of making mouse iPSCs with M3O-SKM to 26% by culturing transduced cells at low density in serum-free culture medium. In contrast, the efficiency increased from 0.1% to only 2% with the combination of wild-type Oct4 and SKM (OSKM) under the same culture condition. For human iPSCs, M3O-SKM achieved 7% efficiency under a similar serum-free culture condition, in comparison to 1% efficiency with OSKM. This study highlights the power of combining the transactivation domain of MyoD with a favorable culture environment

Numerical Study on Roadway Stability under Weak Geological Condition of PT Gerbang Daya Mandiri Underground Coal Mine in Indonesia

This paper aims to assess the roadway stability of the PT Gerbang Daya Mandiri (GDM) underground coal mine. A numerical analysis method using 3D finite difference code (FLAC 3D) was used to investigate the failure zone behavior of the roadway at various overburden depths (50 m, 100 m, 200 m, and 300 m). The outcome of this research was the most appropriate support system of the roadway. The results of numerical analyses indicated that the excavation depth affected the thickness of failure zone, and the capacity of the support system was significantly associated with an increase of the overburden depth. Steel set, cablebolt, and rockbolt supports were assessed in this paper. The steel set is selected as the main support system in GDM coal mine, and it is effective to stabilize the roof and sidewalls of the roadway until 200 m depth. As the failure zone becomes larger at the deeper sites, the cablebolt support is introduced to control the floor stability, and the use of rockbolt in combination with steel set is suggested to support the roof and sidewalls

Structure-property relationships in glass reinforced polyamide, part 2: The effects of average fiber diameter and diameter distribution

We present the results of an extensive study of the influence of average fibre diameter and the width of the diameter distribution on the performance of injection moulded glass-fibre reinforced polyamide 66. In the average fibre diameter range from 9-18m dry-as-moulded (DaM) composite unnotched impact and tensile strength decreased significantly. The composite notched impact performance and tensile modulus showed little dependence on fibre diameter. The influence of broadening the fibre diameter distribution by blending glass fibre samples of different average diameter was found to be particularly negative on the level of composite unnotched impact when compared at equal number average diameter. After hydrolysis treatment the composite tensile strength and modulus exhibited a large drop compared to the DaM results. In contrast, the unnotched impact results became insensitive to fibre diameter after hydrolysis. The average level of unnotched impact after hydrolysis was sufficiently high to show an increase over DaM when the fibre diameter was above 14m. Residual fibre length correlated significantly with fibre diameter with a lower average length for thinner fibres. The interfacial shear strength was found to be in the range of 26-34 MPa for DaM composites. There was a highly significant inverse correlation between the DaM interfacial strength and the average fibre diameter. It is shown that results from both tensile and unnotched impact measurements can be brought back to single trend lines by using a Z average value for the average fibre diameter which is more heavily weighted to the thicker fibres in the distribution