Evaluating data freshness in large scale replicated databases

There is nowadays an increasing need for database replication, as the construction of high performance, highly available, and large-scale applications depends on it to maintain data synchronized across multiple servers. A particularly popular approach, used for instance byFacebook, is the MySQL open source database management system and its built-in asynchronous replication mechanism. The limitations imposed by MySQL on replication topologies mean that data has to go through a number of hops or each server has to handle a large number of slaves. This is particularly worrisome when updates are accepted by multiple replicas and in large systems. It is however difficult to accurately evaluate the impact of replication in data freshness, since one has to compare observations at multiple servers while running a realistic workload and without disturbing the system under test. In this paper we address this problem by introducing a tool that can accurately measure replication delays for any workload and then apply it to the industry standard TPC-C benchmark. This allows us to draw interesting conclusions about the scalability properties of MySQL replication

Improved PWM A/D conversion technique: working principle and model validation

Analog-to-digital conversion plays a central role in any application of digital sensors and sensor systems that require an interface between analog devices, namely analog sensors, and digital devices, namely, microprocessors, digital signal processors or microcontrollers. With the advent of smart sensing, the integration of signal conditioning, analog-to-digital and digital data processing in single hardware devices became a reality. Moreover, the usage of low-cost discrete A/D conversion techniques for applications that are not critic in terms of accuracy, resolution or conversion rate, are considering increasingly mixed hardware and software A/D solutions tailored for specific application demands. In this context, this chapter presents a discrete low-cost A/D conversion solution based on pulse width modulation particularly suited for microcontrollers' integration with smart sensing devices.info:eu-repo/semantics/publishedVersio

The Urban Campus of A Coruña: Citizen Demand and Urban Project

[Resumo] La consecución de centros superiores de enseñanza ha sido una constante demanda de la ciudad de A Coruña, conformándose como un proyecto colectivo que se materializó en 1947 con la inauguración de los primeros edificios de la Ciudad Escolar, ubicada en la zona de Riazor y constituida por una serie de espacios libres y edificios de uso docente. Una ambiciosa propuesta urbana de creación de un conjunto universitario elaborada por el arquitecto Antonio Tenreiro, devino en la construcción de cuatro edificios proyectados por él: la Escuela de Magisterio, el Instituto de Enseñanzas Medias, la Escuela de Comercio y la Escuela de Náutica.[Abstract] The city of A Coruña had long been clamoring for the establishment of institutions of higher education. This demand was materialized in 1947 with the opening of the first buildings belonging to the college campus located in the Riazor area, with facilities that included open spaces and buildings to be used exclusively as classrooms. This ambitious urban project for a university complex designed by the architect Antonio Tenreiro resulted in the construction of four buildings: the School of Education, a High School, the Business School and the Naval Academy

Use of the short form glasgow composite measure pain scale in the assessment of canine patients presenting in shock

Dissertação de Mestrado Integrado em Medicina VeterináriaThe short form of Glasgow Composite Measure Pain Scale (CMPS-SF), a previously validated decision-making tool is increasingly used in practice for the assessment of pain in dogs. However, few studies have considered the application of a pain scoring system in patients presenting in emergency situations. This study aimed to evaluate if pain scoring with the Glasgow CMPS-SF was effective in identifying pain in patients in shock. A prospective study (November 2014 to January 2015), within a first opinion and specialty intensive care service was developed. A total of 31 client-owned dogs (16 females and 15 males) that presented as primary emergencies or transfers. When admitted to the study, all dogs were examined by a veterinarian or registered veterinary nurse. Patients were classified and grouped as Shock (S) or Not Shock (NS) on basis of their shock index (SI). The shock status was defined a priori if the SI was higher than 1.0. Regardless of group, all patients had their pain assessed with the Glasgow CMPS-SF and by a Board Eligible Internist or a Emergency and Critical Care specialist, blinded to both pain score and SI values. Dogs in shock numbered 18/31 dogs within the not shock group numbered 13/31. Mean age of dogs in the S group was 4.6 years (0.2 – 10) and in the NS group was 8.3 years (1 – 16); a significant difference existed in age between groups (p-value<0.05). Median pain score of the S group was 5 (0 – 17) and on the NS group was 3 (1 – 15). There was no significant difference on pain scores between the groups (p-value>0.05) and between the clinicians’ perception of pain between groups (p-value>0.05). A significant difference was present between pain scores and the clinicians’ opinion on pain (p-value=0.014), including within the shock group (p-value=0.0021). Cohen’s kappa statistic within the shock group was 0.47, which can be interpreted as weak to moderate agreement between the Glasgow CMPS-SF and the clinician opinion on pain. Within the NS group the differences between the pain scores and the clinician’ opinion on pain were not statistically significant (p-value>0.05). These results do not support an acceptable agreement between the Glasgow CMPS-SF and an experienced veterinarians evaluation of pain in patients presenting in shock. Therefore, further investigation into the relevance of the used pain assessment tool in emergency and shock patients is recommended before use in the objective monitoring of this subset of patients.RESUMO - USO DA FORMA ABREVIADA DA ESCALA COMPOSTA DA DOR DE GLASGOW EM CÃES COM APRESENTAÇÃO DE CHOQUE - O reconhecimento e avaliação de dor em doentes veterinários pode ser desafiante, especialmente nos que se encontram em estado crítico. A já validada forma abreviada da Escala Composta da Dor de Glasgow (CMPS-SF) é, cada vez, mais utilizada em ambiente clínico na avaliação da dor aguda em cães. Contudo, poucos estudos têm considerado a aplicação de um sistema de avaliação de dor em doentes que se apresentam em situação de emergência. Foi desenvolvido um estudo experimental com o propósito de avaliar se a pontuação obtida com a CMPS-SF seria capaz de identificar dor em doentes que se apresentassem em choque. O estudo prospetivo desenvolveu-se numa clínica de primeira opinião e com serviço de cuidados intensivos (entre Novembro de 2014 e Janeiro de 2015). Foram incluídos no estudo 31 cães, admitidos em situação de emergência ou como referências, tendo sido examinados por um médico veterinário ou uma enfermeira veterinária. Os doentes foram classificados como estando em choque (S) ou não (NS) com base no seu índice de choque (IC). O estado de choque foi definido quando IC>1.0. Todos os doentes foram avaliados quanto à dor pela utilização da CMPS-SF e através de um exame físico realizado por um candidato a Internista ou um especialista em Emergências e Cuidados Intensivos, desconhecedores da pontuação obtida com a escala de CMPS-SF e do IC. O nível de significância estabelecido foi de 0.05. O grupo de cães em choque incluiu 18 cães e o grupo de não choque incluiu 13. A idade média dos animais no grupo S foi de 4.6 anos e no grupo NS foi de 8.3. As diferenças de idade observadas entre os grupos foram consideradas estatisticamente significativas (pvalue< 0.05). A pontuação média de dor no grupo S foi 5 e no grupo N.S. foi 3. As diferenças observadas na pontuação de dor entre os dois grupos grupos não foi considerada significativa (p-value>0.05). A perceção da dor pelos médicos veterinários nos dois grupos também não foi considerada significativa (p-value>0.05). Considerou-se significativa a diferença observada entre as pontuações de dor e a perceção de dor dos médicos veterinários (p-value=0.014), incluíndo no grupo S (p-value=0.0021). No grupo S, a concordância entre métodos foi de 0.47, interpretada como fraca a moderada. Face aos resultados obtidos, sugerem-se mais estudos relativos à precisão da utilização de escalas de dor em doentes que se apresentem em emergência e em condições de choque, antes que estas escalas possam ser recomendadas neste tipo de doentes

Rethinking History through Communication. The "public sphere" as a civic "imagined community" in late 19th century Portugal

info:eu-repo/semantics/publishedVersio

Inventarios post-mortem y riqueza campesina en Extremadura. Aproximación metodológica

Importancia que los inventarios post mortem tienen como fuente para conocer y evaluar la riqueza campesina, durante los siglos XVI, XVII y XVIII, y sus relaciones con otras fuentes documentales

Foundation fieldbus : from theory to practice

This paper describes the main characteristics of the Foundation Fieldbus (FF) technology considering both communication levels, namely H1 and H2, which have bit rates of 31.25 K and 100 Mbit/s, respectively. Several details about the physical layer, communication stack and user layer will be highlighted. Topics related with the configuration of instruments, as well as the design and implementation of supervision software, based on a LabVIEW interface, will be presented. A pilot plant that includes temperature, pressure, level and flow variables will be used to test and validate the capabilities of FF systems. Experimental results will be analyzed, their meaning discussed and the overall performance evaluated