Suchergebnisse

AbstractInventory systems with returns are systems in which there are units returned in a repairable state, as well as demands for units in a serviceable state, where the return and demand processes are independent. We begin by examining the control of a single item at a single location in which the stationary return rate is less than the stationary demand rate. This necessitates an occasional procurement of units from an outside source. We present a cost model of this system, which we assume is managed under a continuous review procurement policy, and develop a solution method for finding the policy parameter values. The key to the analysis is the use of a normally distributed random variable to approximate the steady‐state distribution of net inventory.Next, we study a single item, two echelon system in which a warehouse (the upper echelon) supports N(N ⩾ 1) retailers (the lower echelon). In this case, customers return units in a repairable state as well as demand units in a serviceable state at the retailer level only. We assume the constant system return rate is less than the constant system demand rate so that a procurement is required at certain times from an outside supplier. We develop a cost model of this two echelon system assuming that each location follows a continuous review procurement policy. We also present an algorithm for finding the policy parameter values at each location that is based on the method used to solve the single location problem.

While home visiting programs are among the most widespread interventions to support at-risk families, there is a paucity of research investigating these programs under real-world conditions. The effectiveness of Families First home visiting (FFHV) was examined for decreasing rates of being in care of child welfare, decreasing hospitalizations for maltreatment-related injuries, and improving child development at school entry. Data for 4,562 children from home visiting and 5,184 comparison children were linked to deidentified administrative health, social services, and education data. FFHV was associated with lower rates of being in care by child's first, second, and third birthday (adjusted risk ratio [aRR] = 0.75, 0.79, and 0.81, respectively) and lower rates of hospitalization for maltreatment-related injuries by third birthday (aRR = 0.59). No differences were found in child development at kindergarten. FFHV should be offered to at-risk families to decrease child maltreatment. Program enhancements are required to improve child development at school entry.