2,987 research outputs found

    Propuesta de diseño de mobiliario modular para cocina

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    Molinero Nieto, JC. (2012). Propuesta de diseño de mobiliario modular para cocina. https://riunet.upv.es/handle/10251/17615.Archivo delegad

    The influence of the Atlantic and regional climate variability on the long-term changes in gelatinous carnivore populations in the northwestern Mediterranean

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    We investigated potential connections between climate and the population size of gelatinous carnivores in the northwestern Mediterranean. The interannual variability of large- and meso-scale climate factors was related to gelatinous carnivore dynamics by means of a multivariate regression model. Gelatinous carnivore population dynamics integrate the climate-related changes in the northwestern Mediterranean with close correlations between climate and the population size of the Calycophoran siphonophores Chelophyes appendiculata and Abylopsis tetragona and the Hydromedusae Rhopalonema velatum and Solmundella bitentaculata. We show that the sensitivity of particular gelatinous carnivore species to environmental forcing relates to their seasonal appearance and peak of abundance. Our results advocate the occurrence of short time windows, during which gelatinous carnivores appear more sensitive to environmental conditions, and favorable conditions may therefore substantially enhance their annual peaks. Furthermore, there were threshold values from which climate effects on gelatinous carnivores become noticeable, indicating that the climate-gelatinous carnivore relationship intensifies according to the strength of climate forcing. The possibility of using the North Atlantic climate variability for assessing and predicting interannual abundance changes of these organisms in the northwestern Mediterranean is considered

    Linking fisheries, trophic interactions and climate: threshold dynamics drive herring Clupea harengus growth in the central Baltic Sea

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    How multiple stressors influence fish stock dynamics is a crucial question in ecology in general and in fisheries science in particular. Using time-series covering a 30 yr period, we show that the body growth of the central Baltic Sea herring Clupea harengus, both in terms of condition and weight-at-age (WAA), has shifted from being mainly driven by hydro-climatic forces to an inter-specific density-dependent control. The shift in the mechanisms of regulation of herring growth is triggered by the abundance of sprat, the main food competitor for herring. Abundances of sprat above the threshold of ~18 × 1010 ind. decouple herring growth from hydro-climatic factors (i.e. salinity), and become the main driver of herring growth variations. At high sprat densities, herring growth is considerably lower than at low sprat levels, regardless of the salinity conditions, indicative of hysteresis in the response of herring growth to salinity changes. The threshold dynamic accurately explains the changes in herring growth during the past 3 decades and in turn contributes to elucidate the parallel drastic drop in herring spawning stock biomass. Studying the interplay between different stressors can provide fundamental information for the management of exploited resources. The management of the central Baltic herring stock should be adaptive and take into consideration the dual response of herring growth to hydro-climatic forces and food-web structure for a sound ecosystem approach to fisheries

    Multi-level trophic cascades in a heavily exploited open marine ecosystem

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    Anthropogenic disturbances intertwined with climatic changes can have a large impact on the upper trophic levels of marine ecosystems, which may cascade down the food web. So far it has been difficult to demonstrate multi-level trophic cascades in pelagic marine environments. Using field data collected during a 33-year period, we show for the first time a four-level community-wide trophic cascade in the open Baltic Sea. The dramatic reduction of the cod (Gadus morhua) population directly affected its main prey, the zooplanktivorous sprat (Sprattus sprattus), and indirectly the summer biomass of zooplankton and phytoplankton (top-down processes). Bottom-up processes and climate–hydrological forces had a weaker influence on sprat and zooplankton, whereas phytoplankton variation was explained solely by top-down mechanisms. Our results suggest that in order to dampen the occasionally harmful algal blooms of the Baltic, effort should be addressed not only to control anthropogenic nutrient inputs but also to preserve structure and functioning of higher trophic level

    Trophic cascades promote threshold-like shifts in pelagic marine ecosystems

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    Fisheries can have a large impact on marine ecosystems, because the effects of removing large predatory fish may cascade down the food web. The implications of these cascading processes on system functioning and resilience remain a source of intense scientific debate. By using field data covering a 30-year period, we show for the Baltic Sea that the underlying mechanisms of trophic cascades produced a shift in ecosystem functioning after the collapse of the top predator cod. We identified an ecological threshold, corresponding to a planktivore abundance of ≈17 × 1010 individuals, that separates 2 ecosystem configurations in which zooplankton dynamics are driven by either hydroclimatic forces or predation pressure. Abundances of the planktivore sprat above the threshold decouple zooplankton dynamics from hydrological circumstances. The current strong regulation by sprat of the feeding resources for larval cod may hinder cod recovery and the return of the ecosystem to a prior state. This calls for the inclusion of a food web perspective in management decisions

    Perancangan Sistem Informasi Pengelola Barang/Inventaris Di Jc Komp

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    Inventory information system is a system used to enter inventory data into the database, so that there are no errors in input, output data, and reporting based on the desired data. based on surveys and interviews with jc comp personnel, information was obtained that the existing system in the jc comp warehouse section is still manual. therefore, the system that will be created by the author is the result of a replication of the existing system in the jc comp warehouse section. in addition to the process of input and output of goods, this information system is also equipped with features for creating data reports, input and output of goods, and searching for goods data by item name. with the inventory information system is expected to be useful for the warehouse parts jc comp. By implementing this system in the jc comp warehouse, it is hoped that it can reduce errors that may occur. this system is also expected to further speed up the process of input, output, and report generation, which in turn will help the jc comp warehouseSistem Informasi Persediaan Barang adalah sebuah sistem yang digunakan untuk memasukkan data-data persediaan barang ke dalam database, sehinggga tidak terjadi kesalahan dalam input, output data, dan pembuatan laporan berdasarkan data yang diinginkan. Berdasarkan survey dan wawancara dengan bagian personalia Jc Komp, didapatkan informasi bahwa sistem yang ada dibagian gudang Jc Komp masih manual. Oleh karena itu, sistem yang akan dibuat oleh penulis adalah hasil replikasi dari sistem yang telah ada dibagian gudang Jc Comp. Selain proses input dan output barang, pada sistem informasi ini juga dilengkapi fitur pembuatan laporan data, input, dan output barang, dan pencarian data barang berdasarkan nama barang. Dengan adanya Sistem Informasi persediaan barang ini diharapkan dapat bermanfaat bagi bagian gudang Jc Komp. Dengan diterapkannya sistem ini pada bagian gudang Jc Comp, maka diharapkan dapat mengurangi kesalahan-kesalahan yang mungkin terjadi. Sistem ini juga diharapkan dapat lebih mempercepat proses input, output, dan pembuatan laporan yang pada akhirnya dapat membantu bagian gudang Jc Komp

    Amenable L-2-Theoretic Methods and Knot Concordance

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    We reveal new structures in the topological knot concordance group. As a key ingredient, we develop obstructions using L-2-theoretic methods for amenable groups in Strebel's class recently introduced by Orr and the author. Concerning (h)-solvable knots, which are defined in terms of certain Whitney towers of height h in bounding 4-manifolds, we show the following: for any n>1, there are (n)-solvable but non-(n. 5)-solvable (and therefore nonslice) knots, which are not detected by prior methods using Cochran-Orr-Teichner L-2-signature obstructions as well as Levine algebraic obstructions and Casson-Gordon invariants.X1197sciescopu

    Dynamics of Network Formation Processes in the Co-Author Model

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    This article studies the dynamics in the formation processes of a mutual consent network in game theory setting: the Co-Author Model. In this article, a limited observation is applied and analytical results are derived. Then, 2 parameters are varied: the number of individuals in the network and the initial probability of the links in the network in its initial state. A simulation result shows a finding that is consistent with an analytical result for a state of equilibrium while it also shows different possible equilibria.Dynamics, Network, Game Theory, Model,Simulation, Equilibrium, Complexity
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