Search results for "97"

Zvaigžņotā Debess: 2001, Pavasaris (171)

2001

Contents: J.Ikaunieks and G.Petrov. Plan of the Radio interferometer of the Astrophysical Laboratory of the LAS ; Z.Alksne and L.Reiziņš. Astronomical Calculations by Electronic Computer ; Z.Alksne, A.Alksnis. The First Decade of the Hubble Space Telescope ; Z.Alksne. Both a Planet and a Dust Disk Orbit Iota (ι) Horologii ; Z.Alksne. The Story of Sakurai’s Star is Continuing ; J.Jaunbergs. Space News on the Web ; I.Vilks. Spaceflight. Period of Great Success (1961-1973) ; I.Abakumov. From History of the Photographic Observations of Earth Artificial Satellites ; M.Kūle. Attitude to Person: Modern Variations ; K.Bērziņš. On Friendly Terms with Cosmology: Basic Principles and Models of the Uni…

Unified understanding of intrinsic and extrinsic controls of dissolved organic carbon reactivity in aquatic ecosystems

2022

Despite our growing understanding of the global carbon cycle, scientific consensus on the drivers and mechanisms that control dissolved organic carbon (DOC) turnover in aquatic systems is lacking, hampered by the mismatch between research that approaches DOC reactivity from either intrinsic (inherent chemical properties) or extrinsic (environmental context) perspectives. Here we propose a conceptual view of DOC reactivity in which the combination of intrinsic and extrinsic factors controls turnover rates and determines which reactions will occur. We review three major types of reactions (biological, photochemical, and flocculation) from an intrinsic chemical perspective and further define t…

PV Reconfiguration Systems: a Technical and Economic Study

2017

Dynamical electrical array reconfiguration strategies for grid-connected PV systems have been proposed as solution to improve energy production due to the mismatch effect of PV plants during partial shading conditions. Strategies are based on the use of dynamic connections between PV panels given by the employment of switches that allow for each panel the series, parallel or exclusion connections, physically changing the electrical connections between the related PV modules, consequentially modifying the layout of the plant. Usually the cost of the dynamic matrix is not taken into account. This novel work evaluates the economic advantages obtained by the use of reconfiguration strategies in…

MODELOS DE REPRESENTACIÓN DE LA DIVERSIDAD ÉTNICA EN LA SERIE MIRACULOUS: LAS AVENTURAS DE LADYBUG Y CAT NOIR

2021

The discussions around the role of the media in the dissemination of stereotypes through social representations have been reignited and the need for a positive media representation of ethnic diversity is recognized. Considering how the media functions as a parallel school and that children are the most vulnerable to these messages, we question what models of representation of ethnic diversity are transmitted in the children's 21st century TV series? To answer this question, we use critical discourse analysis as a methodology to access the discourses implicit in the story. We find that ethnic diversity falls on characters of color, migrants, and secondary actions.Therefore, inequalities aree…

New Microbe Killers: Self-Assembled Silver(I) Coordination Polymers Driven by a Cagelike Aminophosphine

2019

New Ag(I) coordination polymers, formulated as [Ag(&micro

Leo Ruuskanen - elämä ja taide

2002

Analysis of Energy Consumption Performance towards Optimal Radioplanning of Wireless Sensor Networks in Heterogeneous Indoor Environments

2014

In this paper the impact of complex indoor environment in the deployment and energy consumption of a wireless sensor network infrastructure is analyzed. The variable nature of the radio channel is analyzed by means of deterministic in-house 3D ray launching simulation of an indoor scenario, in which wireless sensors, based on an in-house CyFi implementation, typically used for environmental monitoring, are located. Received signal power and current consumption measurement results of the in-house designed wireless motes have been obtained, stating that adequate consideration of the network topology and morphology lead to optimal performance and power consumption reduction. The use of radiopl…

Dimensional analysis and stage-discharge relationship for weirs: a review

2017

Deducing the weir flow stage-discharge relationship is a classical hydraulic problem. In this regard Buckingham’s theorem of dimensional analysis can be used to find simple and accurate formulas to obtain the rating curves of different weir types. At first, in this review paper the rectangular weir that is a very common hydraulic structure is studied. It is indicated that the crest shape, approach channel width, obliquity (angle between the weir crest and the direction normal to the flow motion) and vertical inclination (pivot weir) are the key-parameters affecting the flow over the rectangular weirs. The flow over the triangular, labyrinth, parabolic, circular, elliptical, and W-weirs are …

Testing mechanical characteristics of chestnut stakes used in bed sills for stream restoration

2017

Using of wood elements for constructing bed sills in Mediterranean streams, where the banks are not protected by tree vegetation, needs an evaluation of biological and mechanical characteristics for evaluating both the wood durability and the effectiveness of the stream restoration project. Very few studies have dealt both with the decay of mechanical characteristics of wood elements employed for stream restoration works and with the changes over time of physical and chemical wood characters. In this paper, for a wood and stone bed sill located in a stream having no shaded banks, the changes of physical and chemical characters detected after 12, 18, 24, 30, 36, 42 and 48 months on chestnut …

Redesign of a Rural Building in a Heritage Site in Italy: Towards the Net Zero Energy Target

2017

In order to achieve the ambitious objective of decarbonising the economy, it is mandatory, especially in Europe and in Italy, to include the retrofitting of existing buildings. In a country where a large share of existing buildings have heritage value, it is important to design effective retrofit solutions also in historical buildings. In this context, the paper describes the experience of re-design of an existing rural building located in Sicily, inside the ancient Greeks' “Valley of the Temples”. An energy audit was performed on the building, and its energy uses were thoroughly investigated. A building model was developed in the TRNSYS environment and its performances validated. The valid…