Entropic Inequalities for a Class of Quantum Secret Sharing States

It is well-known that von Neumann entropy is nonmonotonic unlike Shannon entropy (which is monotonically nondecreasing). Consequently, it is difficult to relate the entropies of the subsystems of a given quantum state. In this paper, we show that if we consider quantum secret sharing states arising from a class of monotone span programs, then we can partially recover the monotonicity of entropy for the so-called unauthorized sets. Furthermore, we can show for these quantum states the entropy of the authorized sets is monotonically nonincreasing.Comment: LaTex, 5 page

Computationally Secure Hierarchical Self-Healing Key Distribution for Heterogeneous Wireless Sensor Networks

ASTA

Controlled Data Sharing for Collaborative Predictive Blacklisting

Although sharing data across organizations is often advocated as a promising way to enhance cybersecurity, collaborative initiatives are rarely put into practice owing to confidentiality, trust, and liability challenges. In this paper, we investigate whether collaborative threat mitigation can be realized via a controlled data sharing approach, whereby organizations make informed decisions as to whether or not, and how much, to share. Using appropriate cryptographic tools, entities can estimate the benefits of collaboration and agree on what to share in a privacy-preserving way, without having to disclose their datasets. We focus on collaborative predictive blacklisting, i.e., forecasting attack sources based on one's logs and those contributed by other organizations. We study the impact of different sharing strategies by experimenting on a real-world dataset of two billion suspicious IP addresses collected from Dshield over two months. We find that controlled data sharing yields up to 105% accuracy improvement on average, while also reducing the false positive rate.Comment: A preliminary version of this paper appears in DIMVA 2015. This is the full version. arXiv admin note: substantial text overlap with arXiv:1403.212

Mapeo de Actores y Necesidades de Información Agroclimática en los Cultivos de Maíz y Frijol en sitios piloto - Colombia

Este trabajo presenta los resultados del mapeo de actores y necesidades de información agroclimática en los cultivos transitorios de seguridad alimentaria: maíz y frijol arbustivo en sitios piloto en Colombia. A través del mapeo de los actores que transmiten información a los agricultores, la confianza en la información proporcionada, y las necesidades de información para la toma de decisiones, logramos entender el ancho espectro de problemas y prioridades a tomar en cuenta en la producción de estos cultivos, y proponer soluciones útiles, relevantes, confiables, sostenibles y aplicables. Con este enfoque, se llevaron a cabo 27 entrevistas semi-estructuradas con informantes clave y 12 grupos focales con un total de 151 agricultores en los departamentos de Córdoba y Santander. Los resultados evidencian que una de las prioridades de los agricultores es recibir información agroclimática confiable a escala local, que permita tomar mejores decisiones de siembra, variedades, insumos y manejo de suelos y cultivos ante eventos de variabilidad climática. Se evidencia una desconfianza en las instituciones oficiales que transmiten información climática y un sentimiento difuso de falta de interés de las instituciones hacia los pequeños agricultores. Los agricultores se endeudan para lograr producir fríjol arbustivo y maíz o subsidian la producción por otros cultivos, mientras el acceso a un seguro agrícola es limitado. El formato preferido para recibir información climática es a través de mensajes de texto (celular) y mensajes en la radio local. Grupos de interacción presencial o virtual entre agricultores y expertos parecen una alternativa útil y confiable para recibir y compartir información en tiempo real. Sin embargo, los agricultores están interesados en adoptar el manejo agrícola tras un pronóstico si: a) la información es local, b) proviene de una fuente considerada confiable como expertos u otros agricultores, c) se transmite en el momento adecuado para la toma de decisiones y d) si sus efectos son medibles, verificables y validados, por ejemplo, a través de resultados de pilotos o parcelas experimentales en dos años consecutivos. ENGLISH This working paper presents the results of the mapping of actors and of agroclimatic information needs in pilot sites in Colombia for two annual crops, fundamental for food security: maize and bush beans. The mapping of the actors that transmit information to farmers, the confidence the latter have in the information provided, and their information needs for decision-making, allows us to understand the broad spectrum of issues and priorities to be taken into account in the production of these crops, and suggest solutions that are useful, relevant, reliable, sustainable and applicable. Under this assumption, we conducted 27 semi-structured interviews with key informants and 12 focus groups with a total of 151 farmers in the departments of Córdoba and Santander. Results show that one of the priorities of farmers is to receive reliable local agroclimatic information that enables them to take decisions on planting, varieties, inputs, soil and crop management, that address climate variability. We find a generalized distrust of official institutions that transmit weather information, and a feeling that institutions are not interested in smallholders. Farmers resort to indebtedness to produce beans and maize, or subsidize production with cash crops, while access to agricultural insurance is limited. The format preferred to receive weather information is text messages (phone) and information through the local radio. The creation of groups of farmers and experts who interact in person or virtually seem a useful and reliable alternative to receive and share information in real time. However, farmers are only interested in adopting farm management changes after a forecast if: a) the information is local, b) the information is given by a trusted source such as experts or other farmers, c) the information is transmitted at the right time for decision-making d) the effects of taking these decisions are measurable, verifiable and validated, for example, through pilots or results from experimental plots in two consecutive years

Energy Requirements for Quantum Data Compression and 1-1 Coding

By looking at quantum data compression in the second quantisation, we present a new model for the efficient generation and use of variable length codes. In this picture lossless data compression can be seen as the {\em minimum energy} required to faithfully represent or transmit classical information contained within a quantum state. In order to represent information we create quanta in some predefined modes (i.e. frequencies) prepared in one of two possible internal states (the information carrying degrees of freedom). Data compression is now seen as the selective annihilation of these quanta, the energy of whom is effectively dissipated into the environment. As any increase in the energy of the environment is intricately linked to any information loss and is subject to Landauer's erasure principle, we use this principle to distinguish lossless and lossy schemes and to suggest bounds on the efficiency of our lossless compression protocol. In line with the work of Bostr\"{o}m and Felbinger \cite{bostroem}, we also show that when using variable length codes the classical notions of prefix or uniquely decipherable codes are unnecessarily restrictive given the structure of quantum mechanics and that a 1-1 mapping is sufficient. In the absence of this restraint we translate existing classical results on 1-1 coding to the quantum domain to derive a new upper bound on the compression of quantum information. Finally we present a simple quantum circuit to implement our scheme.Comment: 10 pages, 5 figure

Industry 4.0 and smart data as enablers of the circular economy in manufacturing: Product re-engineering with circular eco-design

The digital transformation of manufacturing firms, in addition to making operations more efficient, offers important opportunities both to promote the transition to a circular economy and to experiment with new techniques for designing smarter and greener products. This study integrates Industry 4.0 technologies, smart data, Life Cycle Assessment methodology, and material microstructural analysis techniques to develop and apply a circular eco-design model that has been implemented in the Italian ceramic tile manufacturing industry. The model has been initially adopted in a simulation environment to define five different scenarios of raw material supply, alternative to the current production one. The scenarios were then validated operationally at laboratory scale and in a pilot environment, demonstrating that a proper selection of raw material transport systems significantly improves the environmental performance of the ceramic product. Both the results of the laboratory tests and of the pre-industrial experiments have demonstrated the technological feasibility of the solutions identified with circular eco-design, enabling the re-engineering of the ceramic product as the fifth of the 6Rs of the circular economy. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

Estado del arte de los productos de información climática en Colombia

Este trabajo presenta el inventario del estado del arte de los productos de información climática en Colombia. Se espera que este documento se convierta en una guía, para conocer la oferta de información climática disponible en internet, que es relevante en la toma de decisiones agrícolas, identificando cuáles son sus principales usuarios y cuáles son los mecanismos de flujo de información utilizados. La metodología que orienta este documento se basa en el informe técnico, realizado por CATIE, sobre el estado del arte de los productos de información agroclimática en América Central (CATIE, 2015). Con este enfoque, La información fue colectada a través de búsquedas sistemáticas en el buscador web de Google con palabras clave. Adicionalmente, se realizó la revisión de las páginas Web de organismos como el servicio meteorológico y Ministerios de agricultura y de ambiente, y del sector publico/privado como: gremios, corporaciones y centro de investigación. Los resultados muestran aproximadamente 17 instituciones generando información climática, agroclimática y de seguridad alimentaria para Colombia. La mayoría de publicaciones con información agroclimática de forma periódica proviene de instituciones como IDEAM, CENICAFÉ, CENICAÑA y CIAT-CCAFS vinculadas a los cultivos de interés y difundida por AGRONET, páginas web de cada institución y redes sociales. Se recomienda tener un sistema unificado de consulta (metadato y mapa) sobre información de todas las estaciones meteorológicas activas en el territorio nacional, dada la dificultad para encontrar la información. El ámbito geográfico de las publicaciones abarca en muchos casos la escala nacional, pero se encuentra distintas publicaciones para las principales ciudades, enfoque en departamentos específicos. El tipo de usuarios a los cuales se dirige la información son, en su mayoría para técnicos o servicios de extensión, pero se encuentran algunas publicaciones enfocadas para agricultores a través de boletines en formato físico y medios audiovisuales. Se encontraron varias publicaciones con recomendaciones para apoyar la toma de decisiones en el sector agropecuario, ya sea por cultivos o por región productiva. La periodicidad de las publicaciones varía desde información en tiempo real, corto plazo (días), análisis decadales e información mensual. Se percibe en reuniones con diferentes usuarios de información climática un alto nivel de desconocimiento sobre toda la oferta y utilidad de dicha información para la toma de decisiones en el sector agropecuario

ESSVCS: an enriched secret sharing visual cryptography

Visual Cryptography (VC) is a powerful technique that combines the notions of perfect ciphers and secret sharing in cryptography with that of raster graphics. A binary image can be divided into shares that are able to be stacked together so as to approximately recover the original image. VC is a unique technique in the sense that the encrypted message can be decrypted directly by the Human Visual System (HVS). The distinguishing characteristic of VC is the ability of secret restoration without the use of computation. However because of restrictions of the HVS, pixel expansion and alignment problems, a VC scheme perhaps can only be applied to share a small size of secret image. In this paper, we present an Enriched Secret Sharing Visual Cryptography Scheme (ESSVCS) to let the VC shares carry more secrets, the technique is to use cypher output of private-key systems as the input random numbers of VC scheme, meanwhile the encryption key could be shared, the shared keys could be associated with the VC shares. After this operation, VC scheme and secret sharing scheme are merged with the private-key system. Under this design, we implement a (k; t; n)-VC scheme. Compared to those existing schemes, our scheme could greatly enhance the ability of current VC schemes and could cope with pretty rich secrets

Local, reliable and timely agro-climatic information: a requirement of Colombian farmers

Awareness of climatic information relevant for future decisions through climatic forecasts is not enough to support farmer’s decision-making. It is necessary to look for agricultural management alternatives that allow farmers to adapt to climatic conditions and implement efficient and sustainable management systems, within a framework of effective communication with farmers (Jones, 2003; Pulwarty et al., 2003). In Latin America are very few the initiatives related to climatic forecasts. The Project “Agroclimatic services and food security information for improved decision-making – AgroClimas” aims to support private and public sector actors in Colombia, Guatemala and Honduras to implement and use agro-climatic risk management tools, validated and adjusted to the needs of final users. This info note presents results from a mapping of actors and agro-climatic information needs in crops important for food security (maize and bush beans), in pilot sites of the project in Colombia. The hypothesis underlying the study is that through mapping actors who transmit information (climatic, prices, technical and financial) to farmers, knowing if this information is considered reliable, identifying unattended information needs and preferred formats to receive it that would support production decisions, one can devise useful, relevant, reliable, sustainable applicable solutions