Adhesive Joint Integrity Monitoring Using the Full Spectral Response of Fiber Bragg Grating Sensors

Although adhesive joining has many advantages over traditional joining techniques, their integrity is more difficult to examine and monitor. Serious structural failures might follow if adhesive joint degradation goes undetected. Available non-destructive examination (NDE) methods to detect defects are helpful in discovering defective joints during fabrication. For long-term monitoring of joint integrity, many of these NDE techniques are prohibitively expensive and time-consuming to carry out. Recently, fiber Bragg grating (FBG) sensors have been shown to be able to reflect strain in adhesive joints and offer an economical alternative for on-line monitoring. Most of the available works relied on the peak shifting phenomenon for sensing and studies on the use of full spectral responses for joint integrity monitoring are still lacking. Damage and disbonding inside an adhesive joint will give rise to non-uniform strain field that may chirp the FBG spectrum. It is reasoned that the full spectral responses may reveal the damage status inside the adhesive joints. In this work, FBGs are embedded in composite-to-composite single lap joints. Tensile and fatigue loading to joint failure have been applied, and the peak splitting and broadening of the full spectral responses from the embedded FBGs are shown to reflect the onset and development of damages. A parameter to quantify the change in the spectral responses has been proposed and independent assessment of the damage monitoring capability has been verified with post-damage fatigue tests.

A First Approach for the Treatment of Galvanic Corrosion and of Load-Bearing Capacity of Clinched Joints

Corrosion is a major cause for the failure of metallic components in various branches of the industry. Depending on the corrosion severity, the time until failure of the component varies. On the contrary, a study has shown that certain riveted metal joints, exposed to a short period of mechanical loading and corrosion, have greater fatigue limits. This study gives rise to the question how different corrosion exposure times affect joint metallic components. In the present research, a theoretical approach is developed in order to evaluate the influence of galvanic corrosion on joint integrity of clinched metal joints. At first, the framework for modeling galvanic corrosion is introduced. Furthermore, a simulative investigation of a clinching point is carried out based on the assumption that corrosion leads to a reduction of the contact area which leads to a local increase in contact pressure. For this purpose, the stiffness values of individual elements in a finite element model are reduced locally in the contact area of the undercut and the contact stress along a path is evaluated. Summarizing, a modeling approach is introduced to investigate corrosion effects on load-bearing behavior of clinched joints.

The Effects of Mechanical Scale on Neural Control and the Regulation of Joint Stability

Recent work has demonstrated how the size of an animal can affect neural control strategies, showing that passive viscoelastic limb properties have a significant role in determining limb movements in small animals but are less important in large animals. We extend that work to consider effects of mechanical scaling on the maintenance of joint integrity; i.e., the prevention of aberrant contact forces within joints that might lead to joint dislocation or cartilage degradation. We first performed a literature review to evaluate how properties of ligaments responsible for joint integrity scale with animal size. Although we found that the cross-sectional area of the anterior cruciate ligament generally scaled with animal size, as expected, the effects of scale on the ligament’s mechanical properties were less clear, suggesting potential adaptations in passive contributions to the maintenance of joint integrity across species. We then analyzed how the neural control of joint stability is altered by body scale. We show how neural control strategies change across mechanical scales, how this scaling is affected by passive muscle properties and the cost function used to specify muscle activations, and the consequences of scaling on internal joint contact forces. This work provides insights into how scale affects the regulation of joint integrity by both passive and active processes and provides directions for studies examining how this regulation might be accomplished by neural systems.

Joint Integrity and Strength CAE Simulation Methodology for PHEV Vehicle Skid Plate Assembly

Battery unit skid plate Joint integrity and Strength are key design attributes to ensure Functionality of vehicle. This paper provides an overview of simulation methodology to predict joint integrity and Strength of Battery unit skid plate. Bolt Joint integrity checked against the maximum vertical each wheel spindle loads, which captures maximum bending and twisting. This is the condition in which bolts can experience high load and bolt slippage should check against this load. Skid plate experiences different loading based on drivability and road profile. To simulate severe off road event condition, Maximum load which skid plate experience, applied, as Point load on skid plate at various critical locations to find the deflection and to make sure skid plate is strong enough to protect underneath battery unit.

Pengaruh Independensi, Pengalaman Kerja, Objektifitas dan Integritas Internal Auditor Terhadap Kualitas Audit (Survey Pada Bank Swasta Nasional Di Wilayah Jawa Barat)

Unqualified opinion (WTP) is a statement given oleh independent auditor. Such statement is proclaimed in froud manner and should be known by public. However, a sound statement given by the auditor does not necessarily mean that the organization is free from corruption, fraud or deceit. The purpose of this research is to examine the significance level of independence, working experience, objectivity and integrity to the audit quality, both partially and jointly. Survey with questionnaire was used during this research. collecting data through questionnaireson the interval auditor in national Banks headquartered in west Java.The sampling technique used purposive sampling approach. Samples were deployed in this study were 100 questionnaires in seven Bank is headquartered in West Java. Data analysis was performed by multiple regression model This study reveals that independent, working experience, objectivity and joint integrity affect audit quality. This study also reveals that partially, working experience and integrity have significance affect on audit quality, while independence and objectivity have little significance on the audit quality.