Information visibility and its effect on supply chain dynamics

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2000.Includes bibliographical references (p. 61-64).Supply chains are nonlinear dynamic systems, the control of which is complicated by long, variable delays in product and information flows. In this thesis, we present a novel framework for improving the visibility of information in supply chains by reducing the delays in information flow. We first analyze the growth and evolution of production and operations management software over the past three decades, and the current trends in their development, coupled with recent advances in radio frequency technology, wireless communications, data representation methods, and the internet. Information visibility is identified as one of the key elements for successful implementation of any such software. We analyze the dynamics of a supply chain under different scenarios of information visibility and forecasting decisions with the help of simulations. Possible improvements in supply chain costs are identified, provided information visibility. We propose a framework to achieve information visibility in the supply chain using radio frequency tags, tag readers, product identification codes, an object description language, and the internet.by Yogesh V. Joshi.S.M

Adaptive significance of circadian rhythms biological clocks and darwinian fitness in cyanobacteria

This article does not have an abstract

Optimally-balanced Hash Tree Generation in Ad Hoc Networks

Ideally a hash tree is a perfect binary tree with leaves equal to power of two. Each leaf node in this type of tree can represent a mobile node in an ad hoc network. Each leaf in the tree contains hash value of mobile node’s identification (ID) and public key (PK). Such a tree can be used for authenticating PK in ad hoc networks. Most of the previous works based on hash tree assumed perfect hash tree structures, which can be used efficiently only in networks with a specific number of mobile nodes. Practically the number of mobile nodes may not be always equal to a power of two and the conventional algorithms may result in an inefficient tree structure. In this paper the issue of generating a hash tree is addressed by proposing an algorithm to generate an optimally-balanced structure for a complete hash tree. It is demonstrated through both the mathematical analysis and simulation that such a tree is optimally-balanced and can efficiently be used for public key authentication in ad hoc networks

Challenges in Diabetes Care in India : Sheer Numbers, Lack of Awareness and Inadequate Control

Abstract With an estimated 40 million people suffering from the condition, the largest in any country in the world, diabetes has become a major health care problem in India. Recent epidemiological studies from India point to the great burden due to diabetes and its micro and macrovascular complications. This is primarily because the status of diabetes control in India is far from ideal. Based on the available data, the mean glycated hemoglobin levels are around 9% which is at least 2% higher than the goal currently suggested by international bodies. The IMPROVE study has helped identify the barriers to good control of diabetes both among patients as well as physicians in today’s practice. However the recent ACCORD study points to the dangers of overaggressive treatment, especially in high risk in elderly patients. A balanced approach to improve awareness about diabetes and its control both among patients and the medical fraternity is urgent need of the hour in India. The associated risks of tight control in high risk groups should also be kept in mind

A case for multiple oscillators controlling different circadian rhythms in Drosophila melanogaster

A population of the fruit fly Drosophila melanogaster was raised in periodic light/dark (LD) cycles of 12:12 h for about 35 generations. Eclosion, locomotor activity, and oviposition were found to be rhythmic in these flies, when assayed in constant laboratory conditions where the light intensity, temperature, humidity and other factors which could possibly act as time cue for these flies, were kept constant. These rhythms also entrained to a LD cycle of 12:12 h in the laboratory with each of them adopting a different temporal niche. The free-running periods (t) of the eclosion, locomotor activity and oviposition rhythms were significantly different from each other. The peak of eclosion and the onset of locomotor activity occurred during the light phase of the LD cycle, whereas the peak of oviposition was found to occur during the dark phase of the LD cycle. Based on these results, we conclude that different circadian oscillators control the eclosion, locomotor activity and oviposition rhythms in the fruit fly D. melanogaster

The Sheared Central Venous Catheter?

A fractured central venous catheter (CVC) with embolization of the distal fragment may lead to life-threatening complications. We had inserted a right subclavian CVC in a 68-year-old female which upon a follow-up chest X-ray appeared to have been sheared. A guidewire was inserted through the CVC until the J-tip was just beyond the tip of the CVC which were then withdrawn as a single assembly. We suspected that the tip of the guidewire might have been entrapped in the opening of the middle port, which upon withdrawal of the guidewire could have led to CVC folding upon itself and shearing

Studying the effectiveness of mixed models of community based and institutional based interventions for management of severe acute malnourished children

Background: Children with severe acute malnutrition (SAM) have nine times higher risk of dying than well- nourished children. Child malnutrition can be managed by community based approach (80-85% SAM children) and institution based approach (10-15% SAM children). The objective of the study is to know the effectiveness of the mixed interventions to improve the nutritional status of the children (0-6 yrs), to decrease the prevalence of malnutrition in the children attending ICDS in Rajkot city for combating child malnutrition. Methods: A baseline survey of total registered 26578 children was carried out at 330 anganwadis and 701 SAM children were identified till the end of June 2014. A model of mixed interventions i.e. i) Community based management consisting of special food program, monthly health checkup and treatment and health education to parents, ii) Institution based management of SAM children with complication was planned and implemented since July 2014.Results: 701 children were identified as SAM at the beginning of the intervention while 160 children were SAM at the end of March 2015. The difference in the proportion of SAM children before and after intervention was statistically significant. An improvement of 80.9% in the status of SAM children was seen among boys while 74.1% was seen among girls.Conclusion: Convergence of Health and ICDS activities, high risk approach, community based and institutional management and community awareness in combating the malnutrition showed significant effect. This model can be replicated elsewhere and sustainability may be ensured for long term results.

Ooty occultations of 76 radio sources

Positional and structural information derived from lunar occultations observed at 327 MHz is presented for 76 radio sources, most of them of flux density less than 2×10-26Wm-2Hz-1. Only 16 sources are optically identified. Two of the stronger sources in the list, viz. PKS 1417-19 and MSH 16-205 have a head-tail type of radio structure. PKS 1417-19 appears to be associated with a small chain of faint galaxies. It is interesting that a close group of five radio sources, each with flux density ≥0.5 f.u. appears to be physically associated with the cluster Zw 0210.1 + 1857. One of the five sources coincides with a 19-mag BSO, while none of the other four is identified with an optical object on the basis of positional agreement

The equivalence of four extensions of context-free grammars

There is currently considerable interest among computational linguists in grammatical formalisms with highly restricted generative power. This paper concerns the relationship between the class of string languages generated by several such formalisms, namely, combinatory categorial grammars, head grammars, linear indexed grammars, and tree adjoining grammars. Each of these formalisms is known to generate a larger class of languages than context-free grammars. The four formalisms under consideration were developed independently and appear superficially to be quite different from one another. The result presented in this paper is that all four of the formalisms under consideration generate exactly the same class of string languages

Chemical and environmental vector control as a contribution to the elimination of visceral leishmaniasis on the Indian subcontinent: cluster randomized controlled trials in Bangladesh, India and Nepal

<p>Abstract</p> <p>Background</p> <p>Bangladesh, India and Nepal are working towards the elimination of visceral leishmaniasis (VL) by 2015. In 2005 the World Health Organization/Training in Tropical Diseases launched an implementation research programme to support integrated vector management for the elimination of VL from Bangladesh, India and Nepal. The programme is conducted in different phases, from proof-of-concept to scaling up intervention. This study was designed in order to evaluate the efficacy of the three different interventions for VL vector management: indoor residual spraying (IRS); long-lasting insecticide treated nets (LLIN); and environmental modification (EVM) through plastering of walls with lime or mud.</p> <p>Methods</p> <p>Using a cluster randomized controlled trial we compared three vector control interventions with a control arm in 96 clusters (hamlets or neighbourhoods) in each of the 4 study sites: Bangladesh (one), India (one) and Nepal (two). In each site four villages with high reported VL incidences were included. In each village six clusters and in each cluster five households were randomly selected for sand fly collection on two consecutive nights. Control and intervention clusters were matched with average pre-intervention vector densities.</p> <p>In each site six clusters were randomly assigned to each of the following interventions: indoor residual spraying (IRS); long-lasting insecticide treated nets (LLIN); environmental management (EVM) or control. All the houses (50-100) in each intervention cluster underwent the intervention measures. A reduction of intra-domestic sand fly densities measured in the study households by overnight US Centres for Disease Prevention and Control light trap captures (that is the number of sand flies per trap per night) was the main outcome measure.</p> <p>Results</p> <p>IRS, and to a lesser extent EVM and LLINs, significantly reduced sand fly densities for at least 5 months in the study households irrespective of type of walls or whether or not people shared their house with cattle. IRS was effective in all sites but LLINs were only effective in Bangladesh and India. Mud plastering did not reduce sand fly density (Bangladesh study); lime plastering in India and one Nepali site, resulted in a significant reduction of sand fly density but not in the second Nepali site.</p> <p>Conclusion</p> <p>Sand fly control can contribute to the regional VL elimination programme; IRS should be strengthened in India and Nepal but in Bangladesh, where vector control has largely been abandoned during the last decades, the insecticide treatment of existing bed nets (coverage above 90% in VL endemic districts) could bring about an immediate reduction of vector populations; operational research to inform policy makers about the efficacious options for VL vector control and programme performance should be strengthened in the three countries.</p