A GaAs MMIC chip-set for 10 to 15GHz radio-links applications

This paper describes the development of a GaAs MMIC chip-set for Ku-band radio-links transmitter. This chip-set includes two circuits, a times-two multiplier 5-7.5GHz to 10-15GHz, and a single side band up-converter. The development and the results of these circuits are analysed. The times-two multiplier is based on a specific balanced configuration leading to a very high level of input frequency suppression at the output (typically 50dBc) on a 2.7mm² chip. The mixer circuit is a broadband build-in single side band mixer of 10mm², with typically 30dBc image suppression

Dynamic Procurement of New Products with Covariate Information: The Residual Tree Method

Problem definition: We study the practice-motivated problem of dynamically procuring a new, short life-cycle product under demand uncertainty. The firm does not know the demand for the new product but has data on similar products sold in the past, including demand histories and covariate information such as product characteristics. Academic/practical relevance: The dynamic procurement problem has long attracted academic and practitioner interest, and we solve it in an innovative data-driven way with proven theoretical guarantees. This work is also the first to leverage the power of covariate data in solving this problem. Methodology:We propose a new, combined forecasting and optimization algorithm called the Residual Tree method, and analyze its performance via epi-convergence theory and computations. Our method generalizes the classical Scenario Tree method by using covariates to link historical data on similar products to construct demand forecasts for the new product. Results: We prove, under fairly mild conditions, that the Residual Tree method is asymptotically optimal as the size of the data set grows. We also numerically validate the method for problem instances derived using data from the global fashion retailer Zara. We find that ignoring covariate information leads to systematic bias in the optimal solution, translating to a 6–15% increase in the total cost for the problem instances under study. We also find that solutions based on trees using just 2–3 branches per node, which is common in the existing literature, are inadequate, resulting in 30–66% higher total costs compared with our best solution. Managerial implications: The Residual Tree is a new and generalizable approach that uses past data on similar products to manage new product inventories. We also quantify the value of covariate information and of granular demand modeling

The impact of inventory management on stock-outs of essential drugs in Sub-Saharan Africa: secondary analysis of a field experiment in Zambia

Objective: To characterize the impact of widespread inventory management policies on stock-outs of essential drugs in Zambia’s health clinics and develop related recommendations. Methods: Daily clinic storeroom stock levels of artemether-lumefantrine (AL) products in 2009–2010 were captured in 145 facilities through photography and manual transcription of paper forms, then used to determine historical stock-out levels and estimate demand patterns. Delivery lead-times and estimates of monthly facility accessibility were obtained through worker surveys. A simulation model was constructed and validated for predictive accuracy against historical stock-outs, then used to evaluate various changes potentially affecting product availability. Findings: While almost no stock-outs of AL products were observed during Q4 2009 consistent with primary analysis, up to 30% of surveyed facilities stocked out of some AL product during Q1 2010 despite ample inventory being simultaneously available at the national warehouse. Simulation experiments closely reproduced these results and linked them to the use of average past monthly issues and failure to capture lead-time variability in current inventory control policies. Several inventory policy enhancements currently recommended by USAID | DELIVER were found to have limited impact on product availability. Conclusions: Inventory control policies widely recommended and used for distributing medicines in sub-Saharan Africa directly account for a substantial fraction of stock-outs observed in common situations involving demand seasonality and facility access interruptions. Developing central capabilities in peripheral demand forecasting and inventory control is critical. More rigorous independent peer-reviewed research on pharmaceutical supply chain management in low-income countries is needed

Chronic wounds consultation by telemedicine between a rehabilitation healthcare center and nursing home or home

Saint-Hélier Rehabilitation Center (pôle MPR Saint-Hélier), located in Rennes, has been selected for a regional telemedicine project in 2014 about chronic wounds.AimTo make care access easier for heavy disabilities patients in nursing homes or at home with chronic wounds.MethodThe members of TLM Pl@ies chronic team are specialist doctors and nurses for wounds. On request, the occupational therapist or dietician involve in the consultation (multidisciplinary approach). A secure videoconference (web) is used.ResultsSince July 2014, over 100 teleconsultations have been done. Targeted population is constituted by patients:– whose access to care is decreased due to moving difficulties;– of which the health care team is crossing difficulties in the care process (wound care but also disability, nutrition..).Seventy percent of requests come from the nursing home, 30% from homes (pressure ulcers stages 3 and 4, arterial ulcers, venous or mixed). Middle age: 78 years (20–101 years). Only 3 patients refused. Time to organize the teleconsultation is on average 13 days. Consultations last on average 25 minutes. In 30% of cases the teleconsultation is extended by a real live training time for the nurse at home guided by the TLM Pl@ies chroniques team. We evaluate professional satisfaction and technical satisfaction. Without teleconsultation, in 77% of cases transportation request for consultation would be made, in 5% hospitalization. In 18% no request would be done.Discussion/conclusionThese first results, encouraging, confirms the interest of specialized consultations in medico-social settings, and telemedicine can be an effective solution

Novel robotic assistive technologies: choosing appropriate training for healthcare professionals

One of the key challenges for the training of healthcare professionals (HCPs) is to maintain a good understanding and knowledge of new assistive technologies (ATs) that are currently on the market [1]. Indeed, at present, available training on ATs is limited and does not meet the practice-related needs of HCPs. It is in this context that the ADAPT European project aims to develop a new AT training programme for healthcare professionals, which will also introduce them to the project’s new AT developments - a smart powered wheelchair and a virtual reality wheelchair-driving simulator. The program consists of six multimodal units; five delivered via e-learning and one through a blended method of e-learning and face-to-face sessions. The development of the content is guided by findings from an earlier literature review and an online survey of AT training needs for HCP’s, both undertaken by the ADAPT cross-national research team, comprised of UK and French experts. The level of technical difficulty increases with successive units in order to train all HCPs to use innovative ATs more widely in their practice. A Learning Management System enables the dissemination of the e-learning AT program. Preliminary results from participant unit-specific evaluations available at this stage are overall positive and encouraging