Ultrasonic propagation velocity across wood fiber direction was measured in wooden bridges in order to investigate the possibility of nondestructive deterioration diagnosis of wooden bridges. The measurements were carried out for three different types of wooden bridges. The periodical measurement was also made for one of them to investigate its secular change. The results were : (1) The histogr...

The effective planning for the renewal of water distribution systems requires accurate quantification of the structural deterioration of water mains. Direct inspection of all water mains in a distribution system is almost always prohibitively expensive. Identifying water main breakage patterns over time is an effective and inexpensive alternative to gauge the structural deterioration of a water...

In this paper a deterministic inventory model with imperfect quality have been developed for deteriorating items with two parameters Weibull distribution deterioration and time dependent holding cost. Shortages are allowed and are completely backlogged. The model has been framed to study the items whose deterioration rate increase with time under permissible delay in payments with imperfect qua...

The paper addresses the problem of maximizing the percentage of on-time jobs in a parallel machine environment with sequence dependent deterioration. The deterioration of each machine (and therefore of the job processing times) is a function of the sequence of jobs that have been processed by the machine. Two machine loading strategies are combined with a set of list scheduling algorithms to so...

Many times it happens that units ordered are not of 100% good quality. A deterministic inventory model with imperfect quality is developed when the deterioration rate is Weibull distribution. Here it is assumed that holding cost is time dependent. The model has been framed to study the items whose deterioration rate increase with time under permissible delay in payments with imperfect quality. ...

in paper (2004) chang studied an inventory model under a situation in which the supplier provides the purchaser with a permissible delay of payments if the purchaser orders a large quantity. tripathi (2011) also studied an inventory model with time dependent demand rate under which the supplier provides the purchaser with a permissible delay in payments. this paper is motivated by chang (2004) ...

In the evaluation of structural reliability, a failure is defined as the event in which stress exceeds a resistance that is liable to deterioration. This paper presents a method to combine the two stochastic processes of deteriorating resistance and fluctuating load for computing the time-dependent reliability of a structural component. The deterioration process is modelled as a gamma process, ...

In structural engineering, a distinction can be made between a structure’s resistance and its stress. A failure may then be defined as the event in which—due to deterioration—the resistance drops below the stress. This paper proposes a method to combine the two stochastic processes of deteriorating resistance and fluctuating load for computing the time-dependent reliability of a structural syst...

We develop a two-warehouse production model with imperfect items. Production rate is taken as the linear combination of on-hand inventory and demand, while demand rate is taken as function of time. Most of the researchers consider that the production rate is independent from the demand rate. In this paper we assume production rate as being dependent on the demand rate, and this assumption is mo...

In underground tunnels or caverns, time-dependent deformation or failure of rock mass, such as extending cracks, gradual rock falls, etc., are a costly irritant and a major safety concern if the time-dependent damage of surrounding rock is serious. To understand the damage evolution of rock mass in underground engineering, an in situ experimental testing was carried out in a large belowground t...