Analisis Kegagalan Pada Poros Pompa Senstrifugal Semi-Lean Benfield 107 JA Dengan Menggunakan Finite Element Analysis (Studi Kasus: PT Petrokimia Gresik)

PT Petrokimia Gresik dalam memproduksi amoniak sering mengalami gangguan pada pompa 107 JA akibat kerusakan pada poros pompa 107 JA. Berdasarkan data yang terjadi dilapangan pada tahun 2017 sudah terjadi empat kali pergantian poros dengan jangka waktu relatif pendek. Kerusakan yang tercatat pernah terjadi adalah retak, patah dan bengkok pada poros pompa 107 JA. Untuk itu diperlukan analisis lebih lanjut tentang penyebab kegagalan pada poros. Dalam penelitian ini analisis penyebab kegagalan akan difokuskan pada bentuk pola patahan dan pembebanan yang diterima oleh poros. Penelitian ini diawali dengan studi lapangan dan identifikasi permasalahan yang ada, dengan mempelajari cara kerja pompa 107 JA serta bentuk dari patahan poros. Dilanjutkan dengan mengumpulkan data historis dari pompa 107 JA. Data-data tersebut berupa dokumentasi pola patahan, data historis kerusakan yang pernah terjadi pada pompa 107 JA dan spesifikasi dari pompa 107 JA baik itu desain maupun materialnya. Kemudian mempelajari literatur-literatur yang berhubungan dengan kasus yang serupa, lalu mulai dilakukan analisis pada kerusakan yang ada. Analisis dilakukan dengan dua cara, yaitu dengan pengamatan pola patahan secara visual dan cara kedua menggunakan simulasi. Penggunaan simulasi dimulai dari perhitungan analitis torsi poros yang diterima pada kondisi aktual. Kemudian desain poros di modelkan secara 3D dilanjutkan dengan dilakukan simulasi menggunakan finite element analysis software. Setelah dilakukan kedua analisis diatas, dilakukan analisis data dan pembahasan hasil dari simulasi, yang kemudian dapat diambil kesimpulan dan saran dari hasil penelitian. Hasil yang diperoleh pada pengamatan secara visual adalah kerusakan yang terjadi pada poros pompa Benfield 107 JA terjadi dikarenakan patah fatigue yang ditunjukkan dengan adanya crack propagation pada pola patahan. Hasil tegangan maksimum yang diperoleh dari cycles poros hingga mengalami fracture adalah 655 MPa. Nilai ini sama dengan tegangan fatigue limit material 17-4 PH sebesar 655 MPa. Kemudian dilakukan analisis FEA dengan software finite element didapatkan bahwa material mengalami fracture dengan tegangan sebesar 655,28 MPa dan regangan 0,003372 mm/mm saat poros terdefleksi sejauh 0,2793 mm. ======================================================================================================= Production process of ammonia at PT Petrokimia Gresik is often interrupted by 107 JA pump due to the failure of 107 JA pump shaft. According to reported field data in 2017 there has been four shaft replacement reported with a relatively short amount of time. The recorded failure ever occurred was cracked, broken and bent on the 107 JA pump shaft. Further analysis of failure of the pump shaft is required. In this research, failure causation analysis will be focused on the fracture pattern form and the load received by the shaft. This research started with a field study and problem identification by learning about the work mechanism of 107 JA pump on CO2 removal process and the form of shaft fracture. Followed by collecting the historical data of the 107 JA pump. The particular data is a documentation of the fracture pattern, historical data of 107 JA pump failures and specification of JA 107 pump on both the design and the material. The literature related to the same case is learned, and the analysis of the failure started. Analyzing process has been done in two ways, an observation of fracture pattern visually and by using simulation. The use of simulation begin with torsion analytic calculation received on actual condition. Then shaft design modeled in 3D after that run simulation using finite element analysis software. After the two analyzing process above, the data was analyzed and the result of the simulation was discussed. Finally the conclusion and suggestion of the research was made. The result of the visual observation is that the failure on the shaft of the 107 JA Benfield pump occured because of the fatique fracture showed by a crack propagation found on the fracture pattern. The maximum stress received by the shaft cycles to causing fracture is 655 MPa. This value is equal with the 17-4 PH fatique limit material in the amount of 655 MPa. Then the FEA analysis by finite element software obtained that the material can have fracture with a stress amount of 655,28 MPa dan a strain amount of 0,003372 mm/mm during the deflection of the shaft as far as 0,2793 mm

Estudio de actividad de una maquina enderezadora de aros deportivos semiautomático para el sector automotriz del cantón El Triunfo

El desarrollo de este tema se basa en un estudio de factibilidad de una maquina enderezadora de aros deportivos semiautomático para el sector automotriz del Cantón El Triunfo el cual es un negocio innovador y ademas surge de la necesidad de un local en la que realicen corrección de los daños

Análisis del desarrollo de un centro de respuesta nacional para la República Oriental del Uruguay

Se describen los modelos organizacionales identificados en [Kill03] con el objetivo de unificar la terminología y obtener conocimiento en las formas de organización más comúnmente utilizadas por CSIRTs establecidos. Asimismo se describen las principales ventajas y desventajas de cada modelo y se señalan las situaciones a las que mejor se adapta cada uno. Los diferentes modelos organizacionales son presentados con diferente grado de profundidad y detalle. El detalle es mayor para el modelo Equipo de Seguridad, por ser una forma de organización de hecho muy difundida en nuestro medio, y para el modelo Coordinador por ser el que se ajusta a las características del futuro CERT nacional. Finalmente se compara la canasta de servicios y otras características del futuro CERT nacional con los modelos descritos, verificándose que se ajusta al modelo de CSIRT Coordinador

Comparison of early-, late-, and non-participants in a school-based asthma management program for urban high school students

<p>Abstract</p> <p>Background</p> <p>To assess bias and generalizability of results in randomized controlled trials (RCT), investigators compare participants to non-participants or early- to late-participants. Comparisons can also inform the recruitment approach, especially when working with challenging populations, such as urban adolescents. In this paper, we describe characteristics by participant status of urban teens eligible to participate in a RCT of a school-based, web-based asthma management program.</p> <p>Methods</p> <p>The denominator for this analysis was all students found to be eligible to participate in the RCT. Data were analyzed for participants and non-participants of the RCT, as well as for students that enrolled during the initially scheduled recruitment period (early-participants) and persons that delayed enrollment until the following fall when recruitment was re-opened to increase sample size (late-participants). Full Time Equivalents (FTEs) of staff associated with recruitment were estimated.</p> <p>Results</p> <p>Of 1668 teens eligible for the RCT, 386 enrolled early, and 36 enrolled late, leaving 1246 non-participants. Participants were younger (p < 0.01), more likely to be diagnosed, use asthma medication, and have moderate-to-severe disease than non-participants, odds ratios (95% Confidence Intervals) = 2.1(1.7-2.8), 1.7(1.3-2.1), 1.4(1.0-1.8), respectively. ORs were elevated for the association of late-participation with Medicaid enrollment, 1.9(0.7-5.1) and extrinsic motivation to enroll, 1.7(0.6-5.0). Late-participation was inversely related to study compliance for teens and caregivers, ORs ranging from 0.1 to 0.3 (all p-values < 0.01). Early- and late-participants required 0.45 FTEs/100 and 3.3 FTEs/100, respectively.</p> <p>Conclusions</p> <p>Recruitment messages attracted youth with moderate-to-severe asthma, but extending enrollment was costly, resulting in potentially less motivated, and certainly less compliant, participants. Investigators must balance internal versus external validity in the decision to extend recruitment. Gains in sample size and external validity may be offset by the cost of additional staff time and the threat to internal validity caused by lower participant follow-up.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT00201058">NCT00201058</a></p

Using Vignette-Based Methodology to Examine Study Recruitment in Older African American Adults: A Methods Paper.

This studys objective was to assess which caring recruitment behaviors correlate with the successful recruitment of older African-American adults-a two-step cross-sectional design employing a vignette-based survey methodology. Kristen Swansons middle-range theory of caring was used to guide the examination of African-American adults (65 years of age and older) perceptions of research-study-recruiter recruitment behaviors. This studys main findings are twofold: Step&nbsp;1: Seven of ten invited experts identified major revisions of the two core vignettes, written at an eighth-grade reading level and high school comprehension. Step 2: A 51% response rate yielded findings that this methodology successfully captured older African-American adults perception of research study recruiters behavioral characteristics during the recruitment process. Older African-Americans who received the hypothetical caring vignette were twice as likely to indicate their willingness to enroll in a research study with a high commitment (i.e., brain donation) compared to their counterparts who received the hypothetical uncaring recruitment scenario. Vignette-based survey methodology holds promise as a tool for informing the recruitment of older African-American adults and other minorities into federally funded health-related research studies

Recruitment, Retention, and Intervention Outcomes from the Dedicated African American Dad (DAAD) Study.

A significant proportion of African American (AA) fathers live in households apart from their young children. This living arrangement&nbsp;can have detrimental effects for children, families, and fathers. One hundred seventy-eight (n = 178) AA fathers, not residing with their 2-6-year-old children, were enrolled in a randomized trial to test the Building Bridges to Fatherhood (BBTF) program against a financial literacy comparison condition. BBTF is an intervention that was developed collaboratively with a fathers advisory council of AA fathers who oversaw all aspects of program development. Based upon advisory council feedback, short video scenes captured fathers interacting with their children, their childrens mothers, and other fathers. These video scenes were used to jump start the discussion around fatherhood, parenting, communication, and problem solving during the intervention group meetings. The actors in the video scenes were recruited from the community. Two trained group leaders, using a standardized group leader manual, delivered the intervention. The Money Smart Financial Literacy Program (MSFLP), which served as the comparator, was also delivered by AA men. Program satisfaction was high in both conditions. Even so recruitment and retention challenges influenced the ability to detect father and child outcomes. This study informs the participation of vulnerable urban AA fathers in community-based fatherhood intervention research and provides insight into bolstering engagement in studies focused on this population

A group think tank as a discourse coalition to promote minority nursing faculty retention.

BACKGROUND: The nursing profession will need one million more nurses by 2024, yet nursing schools are turning away applicants due to insufficient numbers of nursing faculty. Likewise, minority nursing faculty are needed in order to attract diverse nursing students who can then address health care disparities. PURPOSE: The purpose of this paper is to describe the use of a group think tank (GTT) as a mentoring strategy for supporting the recruitment and retention of minority nursing faculty. METHOD: Guided by Kotters theory of change, this paper describes the application of the GTT approach with 5 African American (AA) faculty, one AA doctoral student and a cross-cultural mentor. FINDINGS: Results are presented based upon the metrics typically used to support career advancement, promotion and/or tenure. DISCUSSION: The GTT is a promising mentoring model that can be used to integrate cross-cultural and peer mentoring into academic communities to support diversity in academia

Análisis del desarrollo de un centro de respuesta nacional para la República Oriental del Uruguay

Se describen los modelos organizacionales identificados en [Kill03] con el objetivo de unificar la terminología y obtener conocimiento en las formas de organización más comúnmente utilizadas por CSIRTs establecidos. Asimismo se describen las principales ventajas y desventajas de cada modelo y se señalan las situaciones a las que mejor se adapta cada uno. Los diferentes modelos organizacionales son presentados con diferente grado de profundidad y detalle. El detalle es mayor para el modelo Equipo de Seguridad, por ser una forma de organización de hecho muy difundida en nuestro medio, y para el modelo Coordinador por ser el que se ajusta a las características del futuro CERT nacional. Finalmente se compara la canasta de servicios y otras características del futuro CERT nacional con los modelos descritos, verificándose que se ajusta al modelo de CSIRT Coordinador