La educación en Colombia, ¿motor de crecimiento o de estancamiento?

Desde 2001 el Banco de la República ha publicado 18 libros en su Colección de Economía Regional, una serie cuyo propósito es divulgar los trabajos mono­gráficos de los investigadores de su Centro de Estudios Económicos Regionales (ceer), en Cartagena. Las obras contienen los más diversos trabajos, muchos de ellos estudios pioneros centrados en la Costa Caribe, sobre temas como las desi­gualdades regionales, la estructura económica, el comercio exterior, la geografía económica y el capital humano, entre otrosincluye referencias bibliográficas (páginas 285- 286)

Ethernet-based timing system for accelerator facilities: The IFMIF-DONES case

This article presents the design of a timing system for accelerator facilities, which relies on a general networking approach based on standard Ethernet protocols that keeps all the devices synchronized to a common time reference. The case of the IFMIF-DONES infrastructure is studied in detail, providing a framework for the implementation of the timing system. The network time protocol (NTP) with software timestamping and the precision time protocol (PTP) with hardware timestamping are used to synchronize devices with sub-millisecond and sub-microsecond accuracy requirements, respectively. The design also considers the utilization of IEEE 1588 high accuracy default PTP profile (PTP-HA) to provide sub-nanosecond accuracy for the most demanding components. Three different solutions for the design of the timing system are discussed in detail. The first solution considers the deployment of one time-dedicated network for each synchronization protocol, while the second one proposes the integration of the synchronization data of NTP and PTP into the networks of the facility. The third solution relies on the single distribution of PTP-HA to all the systems. The final design aims to be fully based on standard technologies and to be cost-efficient, seeking for interoperability and scalability, and minimizing the impact on other systems in the facility. An experimental setup has been implemented to evaluate and discuss the suitability of the solutions for the timing system by studying the synchronization accuracy obtained with NTP, PTP and PTP-HA under different network conditions. It includes a timing evaluation platform that tries to resemble the network architecture foreseen in the facility. The measured results revealed that PTP is the most limiting protocol for the second solution. Using the default PTP configuration, it tolerates less than 20% of maximum bandwidth utilization for symmetric bidirectional flows, and around 30% in the case of unidirectional flows (server to client or client to server), with the current setup and using switches without enabled timing support. This case study provides a better understanding of the trade-off between bandwidth utilization, synchronization accuracy and cost in these kinds of facilities

Intrinsic Water Transport in Moisture-Capturing Hydrogels

Moisture-capturing hydrogels have emerged as attractive sorbent materials capable of converting ambient humidity into liquid water. Recent works have demonstrated exceptional water capture capabilities of hydrogels while simultaneously exploring different strategies to accelerate water capture and release. However, on the material level, an understanding of the intrinsic transport properties of moisture-capturing hydrogels is currently missing, which hinders their rational design. In this work, we combine absorption and desorption experiments of macroscopic hydrogel samples in pure vapor with models of water diffusion in the hydrogels to demonstrate the first measurements of the intrinsic water diffusion coefficient in hydrogel–salt composites. Based on these insights, we pattern hydrogels with micropores to significantly decrease the required absorption and desorption times by 19% and 72%, respectively, while reducing the total water capacity of the hydrogel by only 4%. Thereby, we provide an effective strategy toward hydrogel material optimization, with a particular significance in pure-vapor environments.Schweizerischer Nationalfonds zur F?rderung der Wissenschaftlichen Forschung 10.13039/501100001711Peer Reviewe

Time-sensitive networking for interlock propagation in the IFMIF-DONES facility

In this study, we have proposed the use of time-sensitive networking (TSN) technologies for the distribution of the interlock signals of the machine protection system of the future IFMIF-DONES particle accelerator, required for implementing the protection mechanisms of the different systems in the facility. Such facilities usually rely on different fieldbus technologies or direct wiring for their transmission, typically leading to complex network infrastructures and interoperability problems. We provide insights of how TSN could simplify the deployment of the interlock network by aggregating all the traffic under the same network infrastructure, whilst guaranteeing the latency and timing constraints. Since TSN is built on top of Ethernet technology, it also benefits from other network services and all its related developments, including redundancy and bandwidth improvements. The main challenge to address is the transmission of the interlock signals with very low latency between devices located in different points of the facility. We have characterized our initial TSN architecture prototype, evaluated the latency and bandwidth obtained with this solution, identified applications to effectively shape the attainable determinism, and found shortcomings and areas of future improvements

Measuring semantic gap between user-generated content and product descriptions through compression comparison in e-commerce.

The significance of user-generated content as a source for business intelligence and analytics has been on the rise since the inception of electronic commerce platforms and has been solidified in the wake of the pandemic due to the prominence of electronic commerce as a sales channel. The prevailing approach to harnessing unstructured data involves the utilization of Artificial Intelligence; however, there exist simpler alternatives capable of yielding valuable information. This article introduces a methodology grounded in information theory to quantify the semantic disparity between the consumer community and product descriptions. This disparity can result in potential misunderstandings in the dialogue among consumers, and incidental costs in the dialogue between consumers and vendors. One plausible explanation for this disparity is that the terminology employed by consumers may possess different meanings compared to that utilized by product description writers. Our methodology employs large corpora of consumer reviews and product descriptions to quantify this semantic disparity across multiple electronic commerce domains through the implementation of random word exchanges and compression. Furthermore, we utilize neural word embeddings to identify specific words exhibiting the greatest semantic drift between reviews and descriptions, thereby providing lexical examples of these gaps. Our findings indicate that lower levels of lexical-semantic gap are associated with better consumer satisfaction

Crecimiento urbano (1965-2005) y sellado antropogénico del suelo en el municipio de Alacant

En la Comunitat Valenciana el cambio en los usos del suelo provocado por la urbanización acelerada ha sido especialmente intenso en los centros metropolitanos costeros; llanos litorales que acogen los suelos con mayor capacidad de uso agrícola y que concentran la mayor parte de la población y las actividades económicas. En este trabajo se analiza la dinámica espacio-temporal de los usos urbanos durante la segunda mitad del siglo XX en el municipio de Alacant, perteneciente al entorno metropolitano de Alacant-Elx. El estudio, metodológicamente, se ha desarrollado en un entorno SIG. A partir de fotogramas aéreos correspondientes a las fechas de 1956, 1985, 1998 y 2005 y mediante métodos de análisis cartográficos con Sistemas de Información Geográfica, se han establecido los cambios acumulativos de los usos urbanos del suelo a escala detallada (1:10.000). Las tipologías de usos seleccionadas han sido tres, dos de ellas urbanas y una tercera no urbana. Las áreas urbanas en las que la superficie construida es superior al 80% se han considerado de Alta Densidad (UAD), clasificándose como Urbanas de Baja Densidad (UBD) las inferiores al 80%. La diferencia entre las dos clases urbanas responde al mayor o menor porcentaje de vegetación o suelo desnudo en la matriz construida. Los resultados muestran la gran expansión de los usos urbanos y el consecuente retroceso de los agrícolas y forestales. El ritmo de crecimiento fue especialmente rápido durante el periodo 1998-2005. Estos cambios se relacionan con las dinámicas económicas y demográficas regionales. La población se ha multiplicado por 3 en los últimos 50 años, mientras que el área dedicada a usos urbanos del suelo se ha quintuplicado durante el mismo periodo. Así, la superficie construida, que representaba 995 ha (4,95% del municipio) en 1956, alcanzaba 4.977 ha (24,75%) en 2005.In the Comunitat Valenciana, land use changes caused by urban growth have affected especially the metropolitan cities of the coastal plains. In these areas the soils often are highly productive and can support an intensive and profitable agricultural system. Most the population, infrastructures, economic activities of the region are concentrated in these urban centres. This paper analyses the spatial and temporal dynamics of the urban use during the second half of the 20th century in the municipality of Alacant, which is located in the Mediterranean metropolitan area of Alacant-Elx, Spain. Urban growth was analyzed in a GIS framework. Photo interpretation of aerial photographs dated from 1956, 1985, 1998 and 2005 was performed to establish the urban use changes at a detailed scale (1:10,000). The land use/cover classes were high-density urban use - UAD- (when built-up area was higher than 80% of the digitized unit) and low-density urban use -UBD- (built-up area lower than 80%). The difference between the two urban classes depends of more or less presence of vegetation or bare soil on the built-up matrix. Results show a very large transformation to urban use mainly since 1998. These changes are linked with the regional economical and demographical dynamics. The population of Alacant is currently 3 times higher than 50 years ago and the built-up area is 5 times higher than in 1956. Whereas in 1956 only 995 ha (4.95 % of the total area) were occupied by urban use, in 2005 this land use covered 4,977 ha (24.75 %)