Preparing the books to read every day is enjoyable for many people. However, there are still many people who also don't like reading. This is a problem. But, when you can support others to start reading, it will be better. One of the books that can be recommended for new readers is experience and education. This book is not kind of difficult book to read. It can be read and understand by the new readers.

Experience and Education.

The use of recommender systems is an emerging trend today, when user behavior information is abundant. There are many large datasets available for analysis because many businesses are interested in future user opinions. Sophisticated algorithms that predict such opinions can simplify decision-making, improve customer satisfaction, and increase sales. However, modern datasets contain millions of records, which represent only a small fraction of all possible data. Furthermore, much of the information in such sparse datasets may be considered irrelevant for making individual recommendations. As a result, there is a demand for a way to make personalized suggestions from large amounts of noisy data.
Current recommender systems are usually all-in-one applications that provide one type of recommendation. Their inflexible architectures prevent detailed examination of recommendation accuracy and its causes. We introduce a novel architecture model that supports scalable, distributed suggestions from multiple independent nodes. Our model consists of two components, the input matrix generation algorithm and multiple platform-independent combination algorithms. A dedicated input generation component provides the necessary data for combination algorithms, reduces their size, and eliminates redundant data processing. Likewise, simple combination algorithms can produce recommendations from the same input, so we can more easily distinguish between the benefits of a particular combination algorithm and the quality of the data it receives. Such flexible architecture is more conducive for a comprehensive examination of our system.
We believe that a user's future opinion may be inferred from a small amount of data, provided that this data is most relevant. We propose a novel algorithm that generates a more optimal recommender input. Unlike existing approaches, our method sorts the relevant data twice. Doing this is slower, but the quality of the resulting input is considerably better. Furthermore, the modular nature of our approach may improve its performance, especially in the cloud computing context. We implement and validate our proposed model via mathematical modeling, by appealing to statistical theories, and through extensive experiments, data analysis, and empirical studies.
Our empirical study examines the effectiveness of accuracy improvement techniques for collaborative filtering recommender systems. We evaluate our proposed architecture model on the Netflix dataset, a popular (over 130,000 solutions), large (over 100,000,000 records), and extremely sparse (1.1%) collection of movie ratings. The results show that combination algorithm tuning has little effect on recommendation accuracy. However, all algorithms produce better results when supplied with a more relevant input. Our input generation algorithm is the reason for a considerable accuracy improvement.

/pdf/a-distributed-architecture-centric-approach-to-computing-31zmh6iinx.pdf

A distributed, architecture-centric approach to computing accurate recommendations from very large and sparse datasets

Trabajo presentado en el 39th CIESM Congress, celebrado en Venecia, Italia, del 10 al 14 de mayo de 2010

/pdf/biodiversity-of-the-mediterranean-sea-estimates-patterns-and-2mjs6mi5cx.pdf

Biodiversity of the Mediterranean Sea: estimates, patterns and threats

In line with global targets agreed under the Convention on Biological Diversity, the number of marine protected areas (MPAs) is increasing rapidly, yet socio-economic benefits generated by MPAs remain difficult to predict and under debate1, 2. MPAs often fail to reach their full potential as a consequence of factors such as illegal harvesting, regulations that legally allow detrimental harvesting, or emigration of animals outside boundaries because of continuous habitat or inadequate size of reserve3, 4, 5. Here we show that the conservation benefits of 87 MPAs investigated worldwide increase exponentially with the accumulation of five key features: no take, well enforced, old (>10 years), large (>100 km2), and isolated by deep water or sand. Using effective MPAs with four or five key features as an unfished standard, comparisons of underwater survey data from effective MPAs with predictions based on survey data from fished coasts indicate that total fish biomass has declined about two-thirds from historical baselines as a result of fishing. Effective MPAs also had twice as many large (>250 mm total length) fish species per transect, five times more large fish biomass, and fourteen times more shark biomass than fished areas. Most (59%) of the MPAs studied had only one or two key features and were not ecologically distinguishable from fished sites. Our results show that global conservation targets based on area alone will not optimize protection of marine biodiversity. More emphasis is needed on better MPA design, durable management and compliance to ensure that MPAs achieve their desired conservation value.

/pdf/global-conservation-outcomes-depend-on-marine-protected-2bjbqmu98v.pdf

Global conservation outcomes depend on marine protected areas with five key features

The Mediterranean Sea is a marine biodiversity hot spot. Here we combined an extensive literature analysis with expert opinions to update publicly available estimates of major taxa in this marine ecosystem and to revise and update several species lists. We also assessed overall spatial and temporal patterns of species diversity and identified major changes and threats. Our results listed approximately 17,000 marine species occurring in the Mediterranean Sea. However, our estimates of marine diversity are still incomplete as yet—undescribed species will be added in the future. Diversity for microbes is substantially underestimated, and the deep-sea areas and portions of the southern and eastern region are still poorly known. In addition, the invasion of alien species is a crucial factor that will continue to change the biodiversity of the Mediterranean, mainly in its eastern basin that can spread rapidly northwards and westwards due to the warming of the Mediterranean Sea. Spatial patterns showed a general decrease in biodiversity from northwestern to southeastern regions following a gradient of production, with some exceptions and caution due to gaps in our knowledge of the biota along the southern and eastern rims. Biodiversity was also generally higher in coastal areas and continental shelves, and decreases with depth. Temporal trends indicated that overexploitation and habitat loss have been the main human drivers of historical changes in biodiversity. At present, habitat loss and degradation, followed by fishing impacts, pollution, climate change, eutrophication, and the establishment of alien species are the most important threats and affect the greatest number of taxonomic groups. All these impacts are expected to grow in importance in the future, especially climate change and habitat degradation. The spatial identification of hot spots highlighted the ecological importance of most of the western Mediterranean shelves (and in particular, the Strait of Gibraltar and the adjacent Alboran Sea), western African coast, the Adriatic, and the Aegean Sea, which show high concentrations of endangered, threatened, or vulnerable species. The Levantine Basin, severely impacted by the invasion of species, is endangered as well.

This abstract has been translated to other languages (File S1).

/pdf/the-biodiversity-of-the-mediterranean-sea-estimates-patterns-38y4s7jond.pdf

The Biodiversity of the Mediterranean Sea: Estimates, Patterns, and Threats

http://vliz.be/imisdocs/publications/103771.pdf

The distribution of hydroids (Cnidaria, Hydrozoa) from micro- to macro-scale: Spatial patterns on habitat-forming algae

The Mediterranean hydrozoan fauna (Siphonophora excluded) comprises 400 species; most (68%) occur in the Atlantic Ocean, 20% are endemic to the Mediterranean, 8% are of Indo-Pacific origin, and 4% are non-classifiable. There are 69 nonindigenous (NIS) species in the basin: 44% of these are casual (recorded just one or very few times), 28% established (widely recorded in the basin), 6% invasive (established NIS that are able rapidly or largely to disseminate away from the area of initial introduction, having a noticeable impact on the recipient community), and 22% questionable (of doubtful taxonomic status). Entry through the Suez Canal and range expansion through the Gibraltar Strait, often enhanced by ship traffic, appear to be the main processes for recent species introductions, but uncertainties remain for many NIS. Species additions immediately result in larger local or regional species pools, but the newcomers might impact on populations of native species, altering extinction probabilities. A more reliable evaluation of the species pool can be accomplished by adding new species when they enter the taxonomic record (i.e. the records of any taxon in all types of literature), and by removing species that have not been found for a ‘reasonable’ time (e.g. several decades). Of the 400 non-siphonophoran hydrozoan species known to occur in the Mediterranean Sea, positive records in the last 10 years are available for 156 species (39%), whereas records of the remaining 244 species are older than a decade: 67 species have not been recorded for 41 years, 13 for 31–40 years, 79 for 21–30 years, and 85 for 11–20 years.

Hydrozoan species richness in the Mediterranean Sea: past and present

Paraphyletic and polyphyletic taxa in the hydroidomedusae result in part from the traditional assignment of similar species to separate genera according to presence or absence of the medusa stage. Medusa reduction is widespread in the Antho- and Leptomedusae and has occurred repeatedly in the same clade. Petersen raised this issue for the Anthomedusae-Capitata, with a thorough taxonomic re-arrangement of the whole group. Advancing knowledge of life cycles allows identification of poly- and paraphyly in other hydrozoan groups, so that phylogenetic interpretation of some "anomalies" in the classification of Antho- and Leptomedusae is possible. Most difficult cases are those leading to "inconsistent" evolution. It is here stressed that the "inconsistency" is due to different rates of change of the two main morphs of the cycle, whereas it is obvious that the species as a whole evolve consistently. The cases of supposed inconsistent evolution considered here are: Zancleidae vs. Corynidae (similar hydroids - different medusae); Anthomedusae vs. swimming gonophores (different hydroids - similar medusae); Clytia vs. Obelia (similar hydroids - different medusae); Stomotoca vs. Hydrichthys (similar hydroids - different medusae); Zancleidae vs. Teissieridae (different hydroids - similar medusae); Clytia vs. Phialella (different hydroids - similar medusae); Mitrocomium-Campalecium vs. Encheilota-Lovenella (different hydroids - similar medusae); Eutima-Eirene vs. Eugymnanthea (similar hydroids - different medusae). In some cases the resemblances are due to convergence, in other cases it is possible to recognize homologies. Resolution of paraphylies, however, may prove difficult. Laomedea, for instance, could represent paedomorphic species of both Clytia and Obelia species, since the hydroids are similar and the difference resides almost exclusively in the gonothecal content. Taxonomy must represent phylogenetic relationships among taxa, but has also to be a useful tool to name taxa and one of its included aims is nomenclatural stability. These two goals are difficult to achieve in hydroidomedusan systematics, especially because the rate of discovery of new taxa and of new life cycle types is still so high that the overall picture is far from being completed. For the sake of stability, it is suggested not to emend generic distinctions leading to supposed paraphyly until the features of the species of such genera have been fully studied.

Classification and phylogeny in the Hydroidomedusae (Hydrozoa, Cnidaria)

The Basking Shark Hall was recently inaugurated in the Marine Biology Museum “Pietro Parenzan” (University of Salento). This provided opportunities to address subjects such as plankton or filter feeding, which are usually disregarded in Marine Biology displays. A questionnaire was administered to visitors (537 students, 9–18 years old) at 3 different times: before the visit to the Basking Shark Hall, immediately after, and after 3 months. Apart from the general trend of positive results emerging from the questionnaires, and a typical progressive diminishing of the acquired information over time, the results highlighted a lack of previous information, the different learning behaviors of males and females, and a different receptivity according to age. The data obtained will be used in elaborating strategies for future didactic proposals in the Marine Biology Museum.

http://www.giurisprudenza.unisalento.it/c/document_library/get_file?uuid=d631e444-ab83-4c5e-b6c3-4cf3f0d2fb4e&groupId=40294311

A Summative Evaluation of Science Learning: A Case Study of the Marine Biology Museum “Pietro Parenzan” (South East Italy)

Epiphytism is a strategy by which opportunistic species such as hydroids, escape the intense levels of competition in marine hard bottom communities. Species of the macroalgae Cystoseira have a seasonal turnover of the frond, and we hypothesise that epiphytic hydroids colonising such an unstable substrate might show some degree of specialisation. Here the first systematic study on hydroid-Cystoseira communities is presented. In particular, the seasonal and spatial distribution of epiphytic hydroids on three species of Cystoseira at two sites of different wave exposure at Porto Cesareo (Ionian Sea/Italy) were investigated. Thirty-two hydroid species were recorded which are well known from other substrates and thus are not specific to Cystoseira; dominant species were all thecates. The influence of biological factors such as competition and the structure and abundance of the host, seem to have little influence on the hydroid community. The factors of greatest influence were mostly abiotic: sedimentation rate, nutrient levels, temperature and most especially water movement. The importance of water movement was evident in the higher colonisation of algal stems, higher hydroid frequency, larger colonies, reduced colony height, species composition, and distribution on the stems at the wave-exposed site.

/pdf/structure-of-an-epiphytic-hydroid-community-on-cystoseira-at-4na9tyzyf7.pdf

Ferdinando Boero

Papers

The distribution of hydroids (Cnidaria, Hydrozoa) from micro- to macro-scale: Spatial patterns on habitat-forming algae

Hydrozoan species richness in the Mediterranean Sea: past and present

Classification and phylogeny in the Hydroidomedusae (Hydrozoa, Cnidaria)

A Summative Evaluation of Science Learning: A Case Study of the Marine Biology Museum “Pietro Parenzan” (South East Italy)

Structure of an epiphytic hydroid community on Cystoseira at two sites of different wave exposure