Logistic Regression Program Rca
Sep 13, 2015. Logistic regression is a method for fitting a regression curve, y = f(x), when y is a categorical variable. The typical use of this model is predicting y given a set of predictors x. The predictors can be continuous, categorical or a mix of both. The categorical variable y, in general, can assume different values. In study I and 549 patients in study II participated in complete follow-up programs, and long-term PCI outcomes were compared within these groups. The statistical methods included Chi-square or Fisher's exact test, student's t-test, stratification methods, multivariate logistic regression and Cox proportional hazards model.
Methods From 1737 patients undergoing PCI between March 2004 and 2005, those with cardiogenic shock, primary PCI, total occlusions, and multivessel or multi-lesion PCI were excluded. Baseline characteristics and in-hospital outcomes were compared in 408 patients with PCI on proximal LAD versus 133 patients with PCI on proximal LCX/RCA (study I) and 244 patients with PCI on non-proximal LAD (study II). From our study populations, 449 patients in study I and 549 patients in study II participated in complete follow-up programs, and long-term PCI outcomes were compared within these groups. The statistical methods included Chi-square or Fisher's exact test, student's t-test, stratification methods, multivariate logistic regression and Cox proportional hazards model. Results In the proximal LAD vs. Proximal LCX/RCA groups, smoking and multivessel disease were less frequent and drug-eluting stents were used more often (p = 0.01, p.
Stenosis of the proximal segment of the left anterior descending coronary artery (LAD) is a special subgroup of coronary artery disease (CAD), given the high-risk profile that these lesions have alone or in the context of multivessel disease [, ]. Patients with proximal LAD occlusion in association with low left ventricular ejection fraction have been reported to have 19-fold higher mortality than the general population [ ]. The data from previous studies suggest that the outcome after revascularization depends on the distribution of prerevascularization coronary artery disease.
In that regard, the severity and location of LAD involvement have been identified as important determinants of outcome in patients with CAD [ ]. This lesion carries a high risk of restenosis after balloon angioplasty with reported patency rate at six month-follow-up of approximately 75% [ ]. However, some studies have shown that stenting may reduce the rate of restenosis in these lesions in comparison with balloon angioplasty [ ]. Specifically, drug-eluting stents have been shown to be related to significantly reduced restenosis rates compared to bare metal stents [, ]. Numerous studies have investigated the outcome of percutaneous coronary intervention (PCI) and bypass surgery in patients with LAD stenosis [,, ].
Generally, the presence of a proximal LAD stenosis has swayed the cardiologists to refer the patients to coronary artery bypass grafting (CABG) presuming these lesions have an overall higher rate of restenosis than proximal left circumflex or right coronary artery [ ]. However, according to the American College of Cardiology/American Heart Association, only type B2/C lesions of the LAD carry a high risk of target vessel revascularization (TVR) and morbidity [ ] and surgery has been proposed as a better option only for such lesions [ ]. According to the 2003 report from the Iranian Statistical Center, 14100 PCI procedures were performed in 50 hospitals in Iran. Of these, approximately 1700 procedures were carried out in Tehran Heart Center (THC). Because of the clinical significance of the lesions located in proximal LAD, our objective in this study was to evaluate the procedural results, in-hospital and long-term clinical outcomes of PCI on proximal LAD, proximal left circumflex (LCX) or right coronary artery(RCA), and non-proximal LAD.
Study population From a total of 1737 consecutive patients undergoing PCI at THC between March 2004 and March 2005, a patient cohort with PCI for de novo narrowing in the proximal segments of coronary arteries or non-proximal LAD were included in the study. Patients with cardiogenic shock, primary PCI, total occlusions, and multivessel or multi-lesion PCI were excluded. Among the 785 remaining patients: 408 had PCI on proximal LAD, 133 underwent PCI on proximal LCX or RCA, and 244 patients were treated with PCI on non-proximal LAD. In study I (n = 541), we compared the outcomes of PCI on proximal LAD versus proximal LCX/RCA. In study II (n = 652), the outcome of PCI on proximal LAD versus non-proximal LAD were compared. Baseline, clinical, angiographic, and procedural characteristics plus in-hospital outcomes were obtained by research physicians and entered into a computerized database by computer operators. Finally, 449 patients in study I and 549 patients in study II agreed to participate in follow-up programs.
They were monitored by cardiologists 1, 5, and 9 months post angioplasty and once a year thereafter. Patient follow up was done in the clinic or by formal telephone interviews.
Clinical data obtained were: major adverse cardiac events (MACE), including cardiac death, non-fatal myocardial infarction (MI), and TVR (CABG or repeated PCI). The data were recorded in data sheets and later transferred into a computerized database.
This study was approved by the THC Ethics Committee. Informed consent was obtained from patients before enrolment into this study.
Definitions Patients already taking hypertensive medication or those whose average of two blood pressure readings at least five minutes apart in the sitting posture was ≥ 140/90 mmHg were labeled as hypertensive [ ]. Patients with a history of taking antihyperlipidemic drugs, total cholesterol ≥ 200 mg/dl or low density lipoprotein ≥ 130 mg/dl were defined as hypercholestrolemic [ ]. Diabetes mellitus was diagnosed to be present if a patient had a definite history of treated diabetes, fasting plasma glucose ≥ 126 mg/dl or two-hour post-load glucose ≥ 200 mg/dl, based on the guidelines of the American Diabetes Association [ ]. Angina symptoms were defined according to the classification of the Canadian Cardiovascular Society [ ]. Lesion types were noted according to the American College of Cardiology/American Heart Association (ACC/AHA) lesion characteristics classification [ ]. Left ventricular ejection fraction was obtained from cardiac catheterization ventriculograms. Q wave MI was defined as the presence of new Q waves in post-procedure electrocardiograms with a 3-fold increase in MB fraction of creatinine kinase.
Non-Q wave MI was defined as a 3-fold increase in MB fraction of creatinine kinase without the development of new Q waves [ ]. Angiographic success was defined as residual stenosis.
Statistical testing was performed by chi-square test or Fisher's exact test (2-tailed) for categorical variables. Student's t-test was used for comparison of continuous variables. Because of the imbalances in some baseline characteristics, the main study results were confirmed by means of stratified analyses and multivariate logistic regression models. Stratification was performed for variables that either had significant imbalance between the groups (p.
Proximal LAD n = 408 Proximal LCX/RCA n = 133 P value (study I) * Non-proximal LAD n = 244 P value (study II) ** Age(yrs) (mean ± SD) 55.36 ± 10.87 56.94 ± 9.7 0.14 55.6 ± 10.88 0.78 Male 285(69.9%) 104(78.2%) 0.06 163(66.8%) 0.41 Diabetes Mellitus 76(19.1%) 33(25.4%) 0. 12 58 (24%) 0.14 Family history of CAD 89(21.8%) 21(15.8%) 0.13 54(22.1%) 0.91 hypercholesterolemia 171(43%) 59(45.4%) 0.63 107(44.2%) 0.76 Current smoker 157(38.5%) 68(51.1%) 0.01 86(35.2%) 0.41 hypertension 132(33.2%) 38(29.2%) 0.4 92(38%) 0.21 Myocardial infarction 138 (33.8%) 38 (28.6%) 0.26 72 (29.5%) 0.25 Prior PCI (Non-target vessel) 15(3.7%) 12(9%) 0.01 7(2.9%) 0.58 Prior CABG 2(0.5%) 2(1.5%) 0.24 1(0.4%) >0.999.
Proximal LAD n = 408 Proximal LCX/RCA n = 133 P value (study I) * Non-proximal LAD n = 244 P value (study II) ** Angiographic characteristics Multivessel disease 110 (33.1%) 64 (61.5%) 45°) 9 (2.2%) 18 (13.5%). Baseline characteristics Table represents selected baseline characteristics of patients treated for proximal stenoses of major epicardial arteries and non-proximal LAD.
Current smoking and prior non-target vessel PCI had a lower frequency in patients with PCI on proximal LAD versus LCX or RCA. However, in patients with PCI on proximal versus non-proximal LAD, the baseline demographic characteristics did not differ. Mean Ejection Fraction was 53.54 ± 9.45% in the proximal LAD versus 53.12 ± 10.24% and 54.35 ± 9.22% in the proximal LCX/RCA and non-proximal LAD groups (p = NS), respectively. In the proximal LAD versus proximal LCX/RCA and non-proximal LAD, the frequency of unstable angina (33.7% vs.
34.8% and 33.7%) and prior MI (33.8% vs. 28.6% and 29.5%) had no statistically significant difference (P = NS). Angiographic and procedural characteristics (Table ) Frequency of type B2/C lesions was similar in the proximal LAD vs. Proximal LCX/RCA and non-proximal LAD groups: (42.8% vs.43.8% and 47.8, p = NS).
Multivessel disease and angulated segments were less frequent in the proximal LAD group. In the proximal LAD versus proximal LCX/RCA group, lesions were longer (16.89 ± 8.1 mm versus 14.68 ± 7.38 mm, p = 0.007) and had lower frequency of proximal segment tortuosity (p = 0.03). However, percentage of lesions smaller than 3 mm in diameter did not differ. On the other hand, in the proximal versus non-proximal LAD group, expectedly, lesions had larger reference vessel diameters.
Stents were used in 99.8% of patients in the proximal LAD versus 98.5% in the proximal LCX/RCA (p = NS) and 96.7% in the non-proximal LAD groups (p = 0.002). Pre- and post-procedural stenosis percentages did not differ significantly in the proximal LAD versus proximal LCX/RCA and non-proximal LAD groups (89.44 ± 8.65% versus 89.15 ± 9.37% and 89.96 ± 8.28%; 0.65 ± 3.24% versus 2.75 ± 13.69% and 1.11 ± 4.51%, p = NS). Patients with PCI on proximal LAD versus proximal LCX/RCA were more commonly treated with drug-eluting stents and had longer stents with smaller diameters. Patients with proximal versus non-proximal LAD stenosis were more often treated with stents, especially the direct stenting technique. In-hospital and late clinical outcomes.
In the proximal LAD group, procedures were angiographically successful in 100% of cases, which was significantly greater than the other two groups. In-hospital events, which occurred only as non-Q wave MI in our cohort, were observed in 8 (2%) in the proximal LAD group, while only 1 patient in the proximal LCX/RCA and non-proximal LAD group (0.8% and 0.4% respectively) displayed such symptoms(P = NS). Procedural success rates were similar in both comparisons (table ).
Mean follow-up duration was 10.81 ± 3.69 months in total population. Major adverse cardiac events at 9-month follow-up, including cardiac death, MI, and TVR (CABG or repeated PCI) were not significantly different in the proximal LAD versus the other two groups (table ). After stratification for factors that either had significant imbalance between the groups or were clinically important, the MACE rates in the proximal LAD versus proximal LCX/RCA and non-proximal LAD groups were still comparable (table ). Similarly, in multivariate logistic regression models, there was no difference in MACE rates in the proximal LAD versus proximal LCX/RCA (p = 0.85, 95% CI = 0.19–3.89, OR = 0.87) and proximal versus non-proximal LAD groups (p = 0.66, 95% CI = 0.29–2.1, OR = 0.8).
Cox proportional hazards model also did not show any difference in MACE-free survival rates at long-term follow-up (figure ). The main finding that emerges from this study is that long-term outcomes of PCI including MACE in patients with proximal LAD stenosis are similar to patients with proximal LCX or RCA and non-proximal LAD stenosis. Also worth noting from our findings was that angiographic success was higher in patients with proximal LAD stenosis. Management of proximal coronary artery disease is important due to the large areas of myocardium that lie downstream of the stenoses. The proximal LAD artery stenosis represents the most important proximal site for obstructive coronary artery after left main stem lesion disease, as it supplies 40%–50% of the total left ventricular myocardium and could result in ischemia to a large area of myocardium [, ]. Moreover, Patients with a critical stenosis of the proximal LAD segment are particularly prone to adverse effects of MI and, therefore, require a safe and long-term effective method of treatment [ ]. Previous studies have demonstrated that interventional treatment produces are more beneficial than pharmacological treatment in severe proximal LAD artery disease [ ].
However, The results of nonstenting PCI to proximal LAD stenoses has been less satisfactory than procedures in the proximal right/circumflex coronary arteries due to higher rates of restenosis in this area [,, ]. Stenting leads to better clinical outcomes than percutaneous transluminal coronary angioplasty in the treatment of isolated lesions of proximal LAD by reducing the risk of restenosis by about 50% [ ]. In fact, stenting of lesions in the proximal LAD is as effective and safe as treatment of lesions located in distal LAD. Therefore, in the current stenting era, location of the lesion in the LAD is not predictive of worse outcome. Furthermore, when stenting is feasible, it may not be taken into account in the choice of revascularization strategy [ ]. However, the re-intervention rates have been higher after bare-metal stenting than bypass surgery of the proximal LAD [ ]. With the advent of drug-eluting stents, a reduction has been achieved in restenosis rates after stenting in proximal LAD.
This in turn has narrowed the 'reintervention gap' between drug-eluting stents enough to eliminate the major advantage of bypass surgery for the treatment of LAD disease [ ]. In our study, no significant difference was observed in rates of major adverse cardiac events during long-term follow-up in the proximal LAD versus the other two groups. Even after adjusting for factors such as stents, particularly drug-eluting stents, which were used most frequently in the proximal LAD group, no statistical difference was detectible. MACE-free survival rates were also similar between the groups (figure ).
Before our study, Ashby et al had studied the outcomes of stenting in proximal LAD versus proximal LCX/RCA [ ]. In their study, multivariate analysis was conducted to adjust these groups for some baseline differences. However, the main endpoint of this study i.e. Rate of TLR, was still similar in both groups in patients treated with stents. Before that, The Stent Restenosis (STRESS) study had shown that irrespective of the procedure used (balloon angioplasty or stenting), the most important predictors of the larger luminal diameter at follow-up were the size of the luminal diameter after the procedure, the initial reference vessel diameter, and the location of a lesion in a vessel other than LAD [ ]. As a secondary aim, we found that angiographic success rate was higher in patients with proximal LAD stenoses. This may be attributed to better accessibility of lesions and higher frequency of stent use in the proximal LAD group.
However, because of the paucity of procedural failure rates, this effect could not be proven by means of statistical analyses. One of the limitations of this study was the relatively small sample size of patients who had developed complications, which made it difficult to determine the predictors of MACE from the multivariate analysis.
On the other hand, we had to exclude patients with multi-lesion or multivessel percutaneous coronary intervention, because otherwise we would not have been able to attribute MACE to a particular lesion site. Acknowledgements We are grateful to Mahmood Sheikh Fathollahi for assisting us in statistical analyses. This study was funded by Tehran Heart Center, which had role in data collections and preparation of datasets for patients.
The authors were funded by the research department of Tehran Heart Center, Medical Sciences/University of Tehran. Competing interests The author(s) declare that they have no competing interests. Authors' contributions MA designed the study, contributed substantially to the interpretation of data and progression of work, and gave the final approval for publication. MRD conducted the data collection and statistical analyses, and participated in writing of the paper. MA, SEK, AHZ, and MS equally performed the angioplasty procedures and contributed to the interpretation of results.
All authors read and approved the final manuscript. Supplementary material.
Chobanian AV, Bakris GL, Black HR, Cushman WC, Green LA, Izzo JL, Jones DW, Materson BJ, Oparil S, Wright JT, Roccella EJ, Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. National Heart, Lung, and Blood Institute; National High Blood Pressure Education Program Coordinating Committee: Seventh report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure.
2003, 42: 1206-52.
Military Handbooks And Standards Plus NASA and Nuclear Regulatory Commission Documents Pertaining To Reliability And Life Cycle Cost Military Handbooks and Standards along with NASA and Nuclear Regulatory Commission documents pertaining to reliability issues are here for quick search and download as PDF files. Brief summaries of each document are provided.
You can also see a for download. Military Standards ( MIL-STD) are generally imposed requirements and give details on what to do. Military Handbooks ( MIL-HDBK) are generally how to do documents intended to standardize and educate.
Military/Government ( AD) are archive direction numbers for technical documents which can ( theoretically) be retrieved from the National Technical Information Service. The Nuclear Regulatory Commission documents have these designators: -( nnn) publications by NRC staff NUREG/BR-( nnn) brochures by NRC staff NUREG/CP-( nnn) conference proceedings by NRC staff -( nnn) publications by NRC contractors NUREG/IA-( nnn) publications resulting from International Agreements Easy access to important reliability documents is a service to the reliability community. If you have other reliability and life cycle cost documents you feel should be included, send an Email notice with their URL’s to. Additional MIL-HDBK, MIL-STD, and Defense/Federal specification documents are available from. Need a free r?
A Redundancy Notebook, December 1997. RADC-TR-77-287 The objective of the report is to present in a coherent fashion the information and tools necessary for the evaluation of most types of redundancy design configurations with which a reliability engineer is faced. The report contains a number of alternative evaluation approaches, both classical and unique. Closed form results and algorithms are derived for the evaluation of the reliability of various types of redundant configurations. Storage Reliability Of Missile Material Program, February 1978. Also identified as LC-78-2 This report summarizes analyses on the non-operating reliability of missile ordnance devices.
The objective of the program is the development of non-operating (storage) reliability prediction and assurance techniques for missile materiel. Included are analyses of solid propellant rocket motors, gas generators, igniters, safe and arm devices, and other explosive devices. Reliability models are developed for each component type. Reliability-Centered Maintenance, December 1978. This is also known as the F.
Stanley Nowlan and Howard F. Heap RCM report, or just the Nowlan & Heap report. This book explains basic concepts, principles, definitions, and applications of a logical discipline for development of efficient schedule (preventive) maintenance programs for complex equipment, and the on-going management of such programs. Such programs are called reliability-centered maintenance (RCM) programs because they are centered on achieving the inherent safety and reliability capabilities of equipment at a minimum costs. Department of Defense objective in sponsoring preparation of this document was that it serves as a guide for application to a wide range of different types of military equipment. There are essentially only four types of tasks in a scheduled maintenance program. Mechanics can be asked to: 1.
Inspect an item to detect a potential failure mode. Rework an item before a maximum permissible age is exceeded. Discard an item before a maximum permissible age is exceeded. Inspect an item to find failures that have already occurred but were not evident to the equipment operating crew A central problem addressed in this book is how to determine which types of scheduled maintenance tasks, if any, should be applied to an item and how frequently assigned tasks should be accomplished.
The use of a decision diagram as an aid in this analysis is illustrated. The net result is a structured, systematic blend of experience, judgment, and operational data/information to identify and analyze which type of maintenance task is both applicable and effective for each significant item as it relates to a particular type of equipment. A concluding chapter emphasizes the key importance of having a mutually supportive partnership between the personnel responsible for equipment design and the personnel responsible for equipment maintenance if maximum RCM results are to be achieved.
Appendices are included as follows: 1. Procedures for auditing the development and implementation of an RCM program. A historical review of equipment maintenance evolution.
Techniques of performing actuarial analyses. An annotated bibliography. The Nowlan & Heap report, slightly modified, is available as bound paperback from the book shop from., Date circa 2009, Pages 50 This guide is written as an overview for both the manager and the analyst. It extends coverage of the design for reliability (DFR) process topics identified in ANSI/GEIA-STD-0009 [ Reliability Program Standard for Systems Design, Development, and Manufacturing was adopted on 20 August 2009 for use by the department of Defense(DoD), and the document is available for US$100 from as. This document consists of the following four objectives: 1.
Understand Customer/User Requirements and Constraints; 2. Design and Redesign for Reliability; 3. Produce Reliable Systems/Products; and 4. Monitor and Assess user Reliability].
The Design For Reliability Handbook expands upon the mathematical and engineering process steps required to ensure robust design. While this manual is intended to provide a general understanding of the concepts and principles required, and serve as an outline to robust design, it is not meant to be employed without project specific tailoring. When used in conjunction with project specifications, it should serve as a basis for identification and planning of the appropriate process steps that should be utilized during the design process thus improving the system reliability of fielded systems. AMSAA-TR-652 AMSAA Reliability Growth Guide, September 2000, Pages 205 Reliability growth is the improvement in a reliability parameter over a period of time due to changes in product design or the manufacturing process. It occurs by surfacing failure modes and implementing effective corrective actions. Reliability growth management is the systematic planning for reliability achievement as a function of time and other resources, and controlling the ongoing rate of achievement by reallocation of these resources based on comparisons between planned and assessed reliability values.
To help manage these reliability activities throughout the development life cycle, AMSAA has developed reliability growth methodology for all phases of the process, from planning to tracking to projection. The report presents this methodology and associated reliability growth concepts. [The technique is also referenced in the literature as reliability growth plots, Crow-AMSAA plots, Crow AMSAA plots, CA plots, C-A plots, C/A plots, Duane Plots, etc. See the.] Because of the file sizes, the report is downloadable in sections:: Pages Cover-24 (1.6 Meg): Pages 18-47 (2.1 Meg): Pages 48-86 (2.2 Meg): Pages 87-133 (2.5 Meg): Pages A1-A5 (0.3 Meg): Pages B1-B43 (3.2 Meg): Pages C1-C8 (0.2 Meg): Pages D1-D12 (0.4 Meg): Pages E1-D3 (0.1 Meg) Development Of A Mathematical Tool For Implementation Of Prognostics Based On Life History, October 2003, 100 pages.
In order to increase mission reliability and reduce the logistics footprint, considerable interest is now being focused on the implementation of prognostics. One approach to prognostics is to track usage in terms of mile, hours or cycles, and generate replacement-before-failure rules for components subject to aging whenever the system is preparing to enter a period during which failures must be zealously avoided (e.g., deployments or combat pulses). This report documents the development and notional application of a new tool that implements this approach. The tool, which is an extension of, generates graphs and tables for a variety of metrics that one could use in an interactive decision-making process. Mathematica is a leading commercial software package for performing mathematics.
Key chapters in this report constitute a basic set of electronic templates for applying the new tool. The tool itself is provided in the appendices. Development Of A Mathematical Tool For Implementation Of A Prognosistics Decision-Making Process Based On Component Life History, March 2006, 134 pages. The key benefit of prognostics is that it can be used to reduce failure risks during deployments and missions when failure is particularly disadvantageous and maintenance inconvenient due to the reduced logistics footprint.
One approach to prognostics is to monitor usage in conjunction with an aging model thereby keeping track of remaining component lifetime. This enables one to track usage with on-board sensors and embed an algorithm in on-system logistics software that will automatically generate maintenance alerts and recommendations so that a covered component can likely be replaced before failure as its remaining lifetime decreases and failure risk increases.
An additional benefit of usage-based prognostics is that it can also be used to identify an optimum replacement age that minimizes life cycle costs for components that age, provided the costs of in-service failure are greater than planned replacement which is often the case. This report documents the development and application of a collection of functions written in that can be used to implement usage-based prognostics using life distributions for components that become less reliable with usage. Directs the acquisition details for Department of Defense Programs (which drives life cycle cost and RAM models).
Directs the management principles. Directs procedures for managing all acquisition programs.
For other RAM details see below., 3 August 2005, 266 pages, 4.17 MB This Guide supports the DoD’s fundamental principles ond procedures as documented in DoD Directive 5000.1 and DoD Instruction 5000.2 to acquire quality products that satisfy user needs with measurable improvements to mission capability and operational support in a timely manner, and at a fair and reasonable price. This guide supports that objective by focusing on the four key steps necessary for building systems with the required levels of RAM: 1. Understand and document user needs and constraints, 2. Design and redesign for RAM 3. Produce reliable and maintainable systems, and 4.
Monitor field experience and sustain RAM performance Chapter 1 introduces RAM, what it is, why it is important, current RAM problems in the DoD, and activities appropriate to achieving satisfactory levels. It concludes with a guide for senior management. Chapter 2 provides an overview of the four-step model for achieving RAM, Chapter 3 focuses on Step 1 including RAM metrics, Joint capabilities integration and development, and pre-acquisition activities.
Chapter 4 focuses on Step 2 and scopes successful approaches for designing-in reliability and maintainability. Chapter 5 focuses on Step 3 and expands this discussion through the testing, production and fielding of capabilities. Chapter 6 focuses on Step 4 and addresses methods for sustaining RAM through the operational life and providing lessons learned for the following generation of capabilities. Throughout the document, the guide also highlights the integration of RAM activities with the defense acquisition management framework, the joint capabilities integration and development system, and the systems engineering technical reviews.
Test & Evaluation of System Reliability, Availability, and Maintainability—A Primer, March 1982. The purpose of this primer is to provide instruction in the analytical assessment of system reliability, availability, and maintainability (RAM) performance. This text presents concepts and techniques for designing test plans which can verify that previously established system suitability requirements have been achieved.
Test resource availability may be adversely affected by cost, schedule and operational urgency constraints. In such cases, alternate test plans which represent the most meaningful, timely and cost effective approach, consistent with these constraints, must be develop.
It is essential that all participants understand the critical issues being addressed and the acquisition risks inherent in conducting a limited test program. The design and execution of sound test programs is no accident. It requires numerous hours of research and planning and a thorough understanding of testing techniques, the test system and its operating scenario.
Further, the test results must support the development of realistic performance estimates for the entire production run, after having tested relatively few systems. Herein lies the usefulness of the statistical concepts contained in this text. Topics addressed in this text will familiarize the reader with the statistical concepts relevant to test design and performance assessment. In short, these topics, when combined with common sense and technical expertise formulate the basis of all sound test programs. Maintainability Design Techniques, March 1988.
232 Pages The purpose of this handbook is to provide Army design engineers with guidelines to assist them in incorporating maintainability into Army materiel early in research and development. Information collected from maintenance records provides practical examples—good and bad—that illustrate the design principles that result in maximum maintainability. The designer can use these principles to build maintainability into materiel and thereby contribute substantially to solving the Army’s maintenance problem. Chapter 1 is an introduction to the principle of maintainability, its importance, and methods of achieving it. The following 10 chapters refer to simplification, standardization and interchangeability, accessibility, modularization, identification and labeling, testability and diagnostics techniques, prevention maintenance, human factors, and environmental factors—describe in detail their role in achieving the maintainability principles. Data includes ergonomic details. Root Cause Analysis Guidance Document, February 1992.
DOE Order 5000.3A, “Occurrence Reporting and Processing of Operations Information,” requires the investigation and reporting of occurrences (including the performance of root cause analysis [RCA]) and the selection, implementation, and follow-up of corrective actions. The level of effort expended should be based on the significance attached to the occurrence. Most off-normal occurrences need only a scaled-down effort while most emergency occurrences should be investigated using one or more of the formal analytical models.
A discussion of methodologies, instructions, and worksheets in this document guides the analysis of occurrences as specified by DOE Order 5000.3A. DOD-STD-1686 concerning electrostatic discharge see DOD-HDBK-263, and which is described below. Hardware Diagnostic Test System Requirements, June 1985, Pages 11 ( This is NOT an authentic copy) This document establishes the general procedures, terms and conditions governing the preparation and completion of a hardware diagnostic test system (HDTS).
The purpose of this Standard is to establish the development criteria for the preparation and completion of the hardware diagnostic test system for systems, subsystems, and equipments. Defense System Software Development, February 1988, Pages 49 This standard establishes uniform requirements for software development that are applicable throughout the system life cycle.
The requirements of this standard provide the basis for Government insight into a contractor’s software development, testing and evaluation efforts. This standard is not intended to specify or discourage the use of any particular software development method. The contractor is responsible for selecting software development methods (for example, rapid prototyping) that best support the achievement of contract requirements. This standard, together with the other DOD and military documents referenced in Section 2, provides the means for establishing, evaluating, and maintaining quality in software and associated documentation. Data Item Descriptions (DIDs) applicable to this standard are listed in Section 6. These DIDs describe a set of documents for recording the information required by this standard. Production of deliverable data using automated techniques is encouraged.
Per DODD 5000.43, Acquisition Streamlining, this standard must be appropriately tailored by the program manager to ensur that only cost-effective requirements are cited in defense solicitations and contracts. Tailoring guidance can be found in DOD-HDBK-248, Guide for Applicable and Tailoring of Requirements for Defense Material Acquisitions.
The is available. Also available is the. The referenced document is also available below along with the. Software Quality Program, 29 April 1988, 15 pages, supersedes MIL-S-52779. This standard contains requirements for the development, documentation, and implementation of a software quality program. This program includes planning for and conducting evaluations of the quality of software, associated documentation, and related activities, and planning for and conducting the follow-up activities necessary to assure timely and effective resolution of problems., System Engineering Fundamentals, January 2001, 222 pages. This book provides a basic, conceptual-level description of engineering management disciplines that relate to the development and life cycle management of a system.
For the non-engineer it provides an overview of how a system is developed. For the engineer and project manager it provides a basic framework for planning and assessing system development. The book is divided into four parts: Introduction; Systems Engineering Process; Systems Analysis and Control; and Planning, Organizing, and Managing.
Review Guide For Criticality Safety Evaluations, September 1999. This Department of Energy Standard is approved for use by all DOE criticality safety personnel. It contains guidelines that should be followed when reviewing Criticality Safety Evaluations that were developed by DOE Contractors to demonstrate the safety of fissile materials handling at DOE Non-Reactor Nuclear Facilities. Adherence to these guidelines will enhance consistency and uniformity of review of Criticality Safety Evaluations across the DOE complex and compliance with either DOE Order 5480.24 or DOW Order 420.1 requirements. Metallic Materials And Elements For Aerospace Vehicle Structures, Rev MIL-HDBK-5H, 1 December 1988. 1653 pages (37 Meg PDF file size!) [Metallic Materials Properties Development and Standardization (MMPDS) prepared by Battelle makes MIL-HDBK-5 obsolete and MMPDS-03 is the current version available in 6 volumes for US$599 for hard copy or US$499 for downloads—please note MMPDS-03 is covered under US Copyright—see for further information.] MIL-HDBK-5H is intended primarily as a source of design allowables, which are those strength properties of metallic materials and elements (primarily fasteners) that are widely used in the design of aerospace structures.
These metallic materials include all systems potentially useful in aerospace and aircraft applications, including those involving reinforcing components. This document also contains information and data for other properties and characteristics, such as fracture toughness strength, fatigue strength, creep strength, rupture strength, fatigue-crack propagation rate, and resistance to stress corrosion cracking. The use of this type of information is not mandatory. In addition to the properties of the materials and elements themselves, there are some of the more commonly used methods and formulas by which the strengths of various structural elements or components are calculated. In some cases, the methods presented are empirical and subject to further refinements. Configuration Management Guidance, Rev A, 7 February 2001. 221 pages (1.4 Meg PDF file size) This handbook provides guidance to DoD managers assigned the responsibility for configuration management on how to ensure the application of product and data configuration management to defense materiel items, in each phase of their life cycle.
Acquisition practices, including the manner in which CM is specified in a contract, and the process of monitoring contractor application are evolving as the result of two interacting transistions. Lists Of Standard Microcircuit Drawings, March 2008, 861 pages The Standard Microcircuit Drawing Program (SMDP) is directly under the auspices of the DoD Parts Management Program (PMP). The PMP is implemented by, “Parts Management.” Sampling Procedures And Tables For Life And Reliability Testing (Base on Exponential Distribution), April 1960. 78 Pages (6 Meg PDF file size) Also referred to as H-108) This handbook has been prepared to meet a growing need for the use of standard sampling procedures and tables for life and reliability testing in Government procurement, supply, and maintenance quality control operations as well as in research and development activities where applicable. A characteristic feature of most life tests is that the observations are ordered in time to failure. If, for example, 20 radio tubes are placed on life test, an t 1 denotes the time where the i th tube fails, the data occur in such a way that t 1 ≤ t 2 ≤≤ t 20.
The same kind of ordered observations will occur whether the problem under consideration deals with the life of electric bulbs, the life of electronic components, the life of all bearings, or the length of life of human beings after they are treated for a disease. The examples just given all involved ordering in time. In destructive testing involving such situations as the current needed to blow a fuse, the voltage needed to break down a condenser, the force needed to rupture a physical material, the test can often be arranged in such a way that every item in the sample is subjected to precisely the same stimulus (current, voltage, stress). If this is done, then clearly the weakest item will be observed to fail first, the second weakest next, etc.
While the random variable considered mostly in this handbook is time to failure, it should be emphasized, however, that the methodology provided herein can be adapted to the testing situations mentioned above where the random variable is current, voltage, stress, etc. Statistical Procedures For Determining Validity Of Suppliers’ Attributes Inspection, 6 May 1960. (2.8 meg PDF file size) Also referred to as H-109. The purpose of this handbook is to provide appropriate statistical tests and tables of critical values to Department of Defense procurement inspection and quality control activities for use in determining the validity of suppliers’ inspection records when sampling inspection by attributes is specified. Such records serve to assure the consumer that only supplies conforming with technical requirements are being offered for acceptance.
Also see: Sampling Procedures and Tables for Inspection by Attributes. Reliability Growth Management, 14 June 2011, 149 Pages, (2.4 Meg PDF file size) This guide provides an understanding of the concepts and principles of reliability growth. Guidelines and procedures to be used in managing reliability growth are also presented. This guide is not intended to serve as a reliability growth plan to be applied to a program without any tailoring. Discrete Mathematics Ensley Pdf Free. When used in conjunction with knowledge of the system and its acquisition program, it will allow for the development of a reliability growth management plan that results in a final system that meets its requirements and lowers the life cycle costs of the fielded system.
[MIL-HDBK-189B Reliability Growth Management, 29 April 2010, Withdrawn because it was approved prior to full document coordination. It is released as MIL-HDBK-189C.] Reliability Growth Management, 10 September 2009. (5.6 Meg PDF file size—contains many different growth models) This handbook provides procuring activities and development contractors with an understanding of the concepts and principles of reliability growth, advantages of managing reliability growth, and guidelines and procedures to be used in managing reliability growth. It should be noted that this handbook is not intended to serve as a reliability growth plan to be applied to a program without any tailoring. This handbook, when used in conjunction with knowledge of the system and its development program, will allow the development of a reliability growth management plan that will aid in developing a final system that meets its requirements and lowers the life cycle cost of the fielded systems. It should be pointed out that this handbook is not intended to cover software reliability growth testing and planning, rather the intent only is to include software failures or incidents coincident as they occur and apply to the failure definition/scoring criteria from testing applicable to addressing reliability growth tracking. Reliability Growth Management, 13 February 1981.
(5.2 Meg PDF file size) This handbook provides procuring activities and development contractors with an understanding of the concepts and principles of reliability growth, advantages of managing reliability growth, and guidelines and procedures to be used in managing reliability growth. It should be noted that this handbook is not intended to serve as a reliability growth plan to be applied to a program without any tailoring.
This handbook, when used in conjunction with knowledge of the system and its development program, will allow the development of a reliability growth management plan that will aid in developing a final system that meets its requirements and lowers the life cycle cost of the fielded systems. [This document describes the Duane method of reliability growth and becomes the Duane AMSAA methodology which today is described as the Crow-AMSAA reliability growth model.] Reliability Prediction Of Electronic Equipment, January 1990. (15.3 Meg PDF file size) The purpose of this handbook is to establish and maintain consistent and uniform methods for estimating the inherent reliability (i.e., the reliability of a mature design) of military electronic equipment and systems. It provides a common basis for reliability predictions during acquisition programs for military electronic systems and equipment.
It also establishes a common basis for comparing and evaluating reliability predictions of related or competitive designs. The handbook is intended to be used as a tool to increase the reliability of the equipment being designed. The application of this handbook contains two methods of reliability prediction – “Part Stress Analysis” in Sections 5 through 23 and “Parts Count” in Appendix A. These methods vary in degree of information needed to apply them. The Part Stress Analysis Method requires a greater amount of detailed information and is applicable during the later design phase when actual hardware and circuits are being designed.
The Parts Count Method requires less information, generally part quantities, quality level, and the application environment. This method is applicable during the early design phase and during proposal formulation.
In general, the Parts Count Method will usually result in a more conservative estimate (i.e., higher failure rate) of system reliability than the Parts Stress Methods. Rome Laboratory – ORACLE is a computer program developed to aid in applying the part stress analysis procedure of MIL-HDBK-217. Based on environmental use characteristics, piece part count, thermal and electrical stresses, subsystem repair rates and system configuration, the program calculates piece part, assembly and subassembly failure rates.
It also flags overstressed parts, allows the user to perform tradeoff analyses and provides system mean-time-to failure and availability. The ORACLE computer program software (available in both VAX and IBM compatible PC versions) is available at replacement tape/disc cost to all DoD organizations, and to contractors for application on specific DoD contracts as government furnished property (GFP) A statement of terms and conditions may be obtained upon written request to: Rome Laboratory/ERSR, Griffiss AFB, NY. [ see software tool] Reliability/Design Thermal Applications, January 1978, 697 Pages. (54 Meg file size!) This handbook has been prepared specifically to guide engineers in the thermal design of electronic equipment with improved reliability. The primary purposes are: to permit engineers and designers, who are not heat transfer experts, to design electronic equipment with adequate thermal performance with a minimum of effort; to assist heat transfer experts, who are not electronic experts; to aid designers in better understanding the thermal selection of Department of Defense specification and standards for equipment; and to assist Navy personnel in evaluating thermal design during the various stages of equipment procurement and development.
This handbook recommends and presents electronic parts stress analysis methods which lead to the selection of maximum safe temperatures for parts so that the ensuing thermal design is consistent with the required equipment reliability. These maximum parts temperatures must be properly selected since they are the goals of the thermal design, a fact with is often overlooked. Many thermal designs are inadequate because improper maximum parts temperatures were selected as design goals. Consequently, the necessary parts stress analysis procedures have been emphasized. Life Cycle Cost In Navy Acquisitions, April 1983. (3.4 Meg file size) This handbook provides basic information on life cycle cost analysis as a management tool for controlling and reducing total costs.
The emphasis is on what the life cycle cost techniques are rather than on how to implement them. The intent is to furnish an overview of the points to address and the procedures to use when performing life cycle cost analysis so that the analyst, wheatear government or contractor, will be better able to conform to the acquisition manger’s objectives. Without going into great depth, those issues of most interest to the beginner are discussed, thus making this handbook particularly used as an initial step in learning about and understand life cycle cost in Navy acquisitions. These issues are: a.
What is life cycle cost b. What are the objectives and requirements of life cycle cost c. What costs are relevant and significant d. What are the analysis procedures e. What data sources and estimating techniques should be used f. When and how to choose or develop a computerized model Experience has show that these are the most pressing questions for those who are undertaking their first life cycle costing effort, and a document which addresses these questions can, in some measure, help to instill a cost management discipline which will result in more efficient cost reduction and cost control efforts in Navy acquisitions. Electrostatic Discharge Control Handbook For Protection Of Electrical And Electronic Parts, Assemblies and Equipment (Excluding Electrically Initiated Explosive Devices), July 1994.
(15.1Meg PDF file size) This handbook provides guidance, not mandatory requirements, for the establishment and implementation of an Electrostatic Discharge (EDS) Control Program in accordance with the requirements of MIL-STD-1686. Nanny Mania 2 Free Download No Time Limit. This document is applicable to the protection of electrical and electronic parts, assemblies and equipment from damage due to ESD.
It does not provide information for the protection of electrically initiated explosive devices. Various segments of industry are aware of the damage static electricity can impose on metal oxide semiconductor (MOS) parts. The sensitivity of other parts to electrostatic discharge damage has also become evident through use, testing, and failure analysis. Trends in technology utilizing new materials, processes and design techniques, including increased packaging densities result in some parts being more susceptible to ESD. Electrical and electronic parts which have been determined to be ESD sensitive (ESDS) include: microelectronic discrete and integrated semiconductor devices; thick and thin film resistors, chips and hybrid devices; and piezoelectric crystals.
Subassemblies, assemblies and equipment containing these parts are also ESDS. Materials which are prime generators of electrostatic voltages include, but are not limited to, common plastics such as polyethylene, vinyls, foam, polyurethane, synthetic textiles, fiberglass, glass, rubber, and other commonly used materials. Damaging electrostatic voltage levels are commonly generated by contact and subsequent separation of these materials by industrial processes and personnel movement. Electrical Grounding For Aircraft Safety, 1 November 1983 with change notices for 29 June 1990.
(14.4 Meg PDF file size) The purpose of this handbook is to provide aircraft maintenance personnel with the information required for electrical safety grounding of each type of operational aircraft in the U.S. Navy inventory. In addition, this handbook provides background information pertaining to the operational concerns for aircraft grounding, static electricity theory and how it affects aircraft, and techniques used for measurement of grounding points. Life Cycle Cost Model For Defense Materiel Systems Data Collection Workbook, February 1984. (29.5 Meg PDF file size) This handbook describes the elements to be considered in determining the life cycle cost of a materiel system. These cost elements and cost factors form the input and output structure of the Life Cycle Cost Model for Defense Materiel Systems. The handbook is meant to be a workbook for determining life cycle costs.
Normally, a subset of the cost structure contained in this handbook and the Model will be prescribed for any given procurement. The emphasis is on what costs should be considered in developing life cycle cost estimates for controlling and reducing total costs. The handbook and the Model are specifically designed to give the analyst and the program manger complete control over the subset of the Model’s cost elements which is applicable to the system being costed and to select the most appropriate cost estimating methodology for each cost element. A Guide for DOD-STD-2168 Defense System Software Quality Program, December 1990. This handbook describes the intent of DOD-STD-2168’s requirements, interprets those requirements, and provides recommendations for applying the standard on a software acquisition or support contract. See above and below.
A Tailoring Guide for DOD-STD-2167A, Defense System Software Development, August 1989, 210 Pages. This handbook provides guidance to Government program managers and other program office staff responsible for tailoring for a software development or support contract. It explains key concepts of DOD-STD-2167A, presents tailoring considerations for DOD-STD-2167A, and describes how to tailor the standard and its associated Data Item Descriptions. Electronic Reliability Design Handbook, October 1998. This Handbook provides procuring activities and development contractors with an understanding of the concepts, principles, and methodologies covering all aspects of electronic systems reliability engineering and cost analysis as they relate to the design, acquisition, and deployment of DoD equipment/systems. The sections include.