Decline and repair, and covariate effects

The failure processes of repairable systems may be impacted by operational and environmental stress factors. To accommodate such factors, reliability can be modelled using a multiplicative intensity function. In the proportional intensity model, the failure intensity is the product of the failure intensity function of the baseline system that quantifies intrinsic factors and a function of covariates that quantify extrinsic factors. The existing literature has extensively studied the failure processes of repairable systems using general repair concepts such as age-reduction when no covariate effects are considered. This paper investigates different approaches for modelling the failure and repair process of repairable systems in the presence of time-dependent covariates. We derive statistical properties of the failure processes for such systems

The Role of Boundary Conditions in the Real-Space Renormalization Group

We show that the failure of the real-space RG method in the 1D tight-binding model is not intrinsic to the method as considered so far but depends on the choice of boundary conditions. For fixed BC's the failure does happen. For free BC's we present a new analytical block RG-method which gives the exact ground state of the model and the correct $1/N^2$-law for the energy of the first excited state in the large $N$(size)-limit. We also give a reconstruction method for the wave-functions of the excited states.Comment: LATEX file, 12 pages, 5 figures available upon reques

Black-Hole Uncertainty Entails an Intrinsic Time Arrow. a Note on the Hawking-Penrose Controversy

Any theory that states that the basic laws of physics are time-symmetric must be strictly deterministic. Only determinism enables time reversal of entropy increase. A contradiction therefore arises between two statements of Hawking. A simulation of a system under time reversal shows how an intrinsic time arrow re-emerges, destroying the time reversal, when even slight failure of determinism occurs.Comment: 9 pages, 4 figure

Evaluation of closed cubic failure criterion for graphite/epoxy laminates

An analytical method has been developed to ensure closure of the cubic form of the tensor polynomial strength criterion. The intrinsic complexity of the cubic function is such that special conditions must be met to close the failure surface in three-dimensional stress space. These requirements are derived in terms of non-intersecting conditions for asymptotes and an asymptotic plane. To demonstrate the validity of this approach, closed failure surfaces were derived for two graphite/epoxy material systems (3M SP288-T300 and IM7 8551-7). The agreement of test data with this model clearly shows that it is possible to use a higher order cubic failure theory with confidence

The Failure of "Chinese Intrinsic Form"

Architectural trends in modern China have evolved into four stages over the course of history : from the “Chinese Form” in the 1900s, to the "Chinese Intrinsic Form" in the 1930s, to the "Ethnic Form" in the 1950s, and to the "New Ethnic Form" in the 1980s.“Chinese Intrinsic Form” can be defined as an assembly of interrelated structural components -- wood-like columns, beams and corbel brackets -- of traditional Chinese construction reforming  with a more sophisticated western technology, but in a holistic and unified manner. It mainly employed for administrative buildings, exhibition halls, commemorative buildings, gymnasiums and commercial buildings. A distinctive attribute of “ Chinese Intrinsic Form ” is its general layout of spatial sequence, as determined by the axisymmetric plane composition,  interior configuration, and form of facade.The new era in nationalism promoting began when “Chinese Intrinsic Form” came into being in 1927. The Chinese architects wanted national pride of expression for the semi-colonial society of the day 1 without considering how their thoughts and design might aid or hinder the modern evolution of architecture in China. Or the true aspiration may be obscured through neglect rather than intent. In either event, notable questions arise as to whether the representing implication about "Chinese Intrinsic Form" is more about political or academic.This paper is indent to discuss the historical background of "Chinese intrinsic form" and its architectural cases in order to explore the reasons why it failed

On an intrinsic approach of the guiding-center anholonomy and gyro-gauge-arbitrariness

In guiding center theory, the standard gyro-angle coordinate is associated with gyro-gauge dependence, the global existence problem for unit vectors perpendicular to the magnetic field, and the notion of anholonomy, which is the failure of the gyro-angle to return to its original value after being transported around a loop in configuration space. We analyse these three intriguing topics through the lens of a recently proposed, global, gauge-independent gyro-angle. This coordinate is constrained, and therefore necessitates the use of a covariant derivative. It also highlights the intrinsic meaning and physical content of gyro-gauge freedom and anholonomy. There are, in fact, many possible covariant derivatives compatible with the intrinsic gyro-angle, and each possibility corresponds to a different notion of gyro-angle transport. This observation sheds new light on Littlejohn's notion of gyro-angle transport and suggests a new derivation of the recently-discovered global existence condition for unit vectors perpendicular to the magnetic field. We also discuss the relationship between Cartesian position-momentum coordinates and the intrinsic gyro-angle

In vitro effect of canine hyperimmune sera on TNFa activity

[Introduction]: Septic shock in dogs is caused by cardiovascular and vasomotor failure associated with an uncontrolled intrinsic release of inflammatory mediators [1–5]. The syndrome is characterized by cardiovascular dysfunction, vascular permeability alterations, pulmonary oedema and tissue hypoxia resulting from microthrombi which may culminate in disseminated intravascular coagulation and catastrophic multiple organ failure [6,7]. Systemic bacterial infection, particularly by Gram-negative enterobacteria, haemorrhagic trauma, gastric dilation/volvulus and pancreatitis are the major underlying causes leading tosepsis [8,9]. Because of haemodynamic instability and associated hypovolemia, fluid replacement therapy is generally applied to restore effective circulating volume. The use of fresh frozen plasma has been recommended in cases of coagulopathies as it has been recognized to assist restoration of haemodynamic stability [1,5,10,11]. There is increasing evidence that the drivers of the haemodynamic instability are inflammatory mediators (particularly TNFa) activated primarily by bacterial endotoxin [3,4,12,13]

Using megaproject performance outcomes to enhance decision-making behaviours in civil engineering graduates

A comprehensive review of megaproject performance propositioned the issues leading to project failure as behavioral. Project failure linked cost overruns and schedule delays to acts of delusion and deception, citing the ability to learn lessons, and the misalignment of incentives as influencing factors. A mixed-methods study was designed to gain insight into the decision-making behaviors of undergraduate civil engineers, and the role that education could play in enhancing decision-making. A co-curricular intervention led to qualitative exploration of decision-making in civil engineering undergraduates. Motivation featured heavily, particularly a conflict between interest and enjoyment, and the reward structures of traditional education and industry. Results led to a quantitative measure of intrinsic motivation and critical thinking ability. Findings from the educational environment have implications for industry and led to recommendations regarding the importance of autonomy and relatedness, to a megaproject environment

Damage-imperfection indicators for the assessment of multi-leaf masonry walls under different conditions

The complexity of multi-leaf masonry walls suggests further researches on the dy- namic behaviour mainly characterized by incoherent response between the different layers. The intrinsic discontinuity and the manufacturing imperfections are amplified by the incre- mental damage that triggers different failure mechanisms that affect the dynamic parameters, such as modal shapes, frequencies and damping ratios. The dynamic identification with out- put only methodology has been proposed in this work on different multi-leaf masonry walls subjected to uniaxial compressive load. The responses of full infill, damaged infill and strengthened infill masonry panels with different widespread damage have been recorded. The evolution of the damage scenario changes the modal shapes, the related frequencies and the damping ratios that through the comparison with the data of the initial conditions can de- tect the anomalies and then the intrinsic vulnerabilities. Through the curvature modal shape methods and the structural irregularity indices applied to different phases, it was possible evaluate the imperfection and the induced damage entity