Hasil untuk "General Works"

José Bragança de Miranda, Carlos Camponez, José Gomes Pinto

Doutorado em Ciências da Comunicação e com a agregação em Teoria da Cultura pela Universidade Nova de Lisboa, José Bragança de Miranda, em entrevista à Biblos, reflete sobre o tema da liberdade, cruzando a Comunicação, a Filosofia, a História e a Política. Refratário às lógicas monistas do pensamento e das organizações, o atual reitor da Universidade Lusófona considera que, a ter existido, o fim da História abriu-se com as Revoluções que conduziram ao controlo do poder absoluto. Reconhecendo que o controlo desse poder não é uma conquista definitiva, José Bragança de Miranda defende, no entanto, que a História mostra que a escolha do pior não se apresenta como uma inevitabilidade para a Humanidade. Por isso, mais do que discutir conceitos como a Liberdade, considera que é importante fazer uso deles, atualizando em cada ínfimo presente o legado de muitos heróis do passado.

Xiaofeng Su, Xiaoli Jiang, Anxin Xu

In China, the implementation of the rural revitalization strategy provides a broad stage for migrant workers to return home to start their own businesses. This study constructs a research framework of “competence – legitimacy – performance.” Through online and offline surveys, this study obtained 477 valid samples from new family farm entrepreneurs in Fujian province of China. By using structural equation model, this study explores the relationship between entrepreneurial competence and family farm entrepreneurial performance. The empirical analysis results show that all the five dimensions of family farm entrepreneurs’ entrepreneurial competence, namely, opportunity recognition competence, network competence, resource acquisition competence, entrepreneurial learning competence, and improvisational competence have positive impacts on family farm entrepreneurial performance. And organizational legitimacy also has a positive impact on family farm entrepreneurial performance. In addition, the mediating effect of organizational legitimacy in opportunity recognition competence, network competence, resource acquisition competence, entrepreneurial learning competence, and family farm entrepreneurial performance are supported by data. However, organizational legitimacy does not play a significant mediating role in the relationship between improvisational competence and family farm entrepreneurial performance. The research findings provide some enlightenment and reflections to family farm entrepreneurs and policy-makers.

Eleanor Wiske Dillon, Sonia Jaffe, Nicole Immorlica et al.

We present evidence from a field experiment across 66 firms and 7,137 knowledge workers. Workers were randomly selected to access a generative AI tool integrated into applications they already used at work for email, meetings, and writing. In the second half of the 6-month experiment, the 80% of treated workers who used this tool spent two fewer hours on email each week and reduced their time working outside of regular hours. Apart from these individual time savings, we do not detect shifts in the quantity or composition of workers' tasks resulting from individual-level AI provision.

Martín Chicolino

El presente estudio monográfico (que se divide en dos artículos que serán publicados consecutivamente en esta revista) está dedicado a estudiar la manera en que Gilles Deleuze abordó el problema psico-político de la dominación y de la violencia psico-sexo-política masculina. Para ello, será necesario partir de la pregunta que interroga acerca de la relación genética que el Patriarcado (en tanto que mega-red de relaciones de alianzas masculinas de sexo-poder) guarda con el Estado (en tanto que forma de organizar la sociabilidad humana) y con el Capitalismo (en tanto que modo de organizar la productividad humana). Con respecto a dicha relación genética, Deleuze postulará, siguiendo al sinólogo marxista Ferenc Tökei, que ‘esclavo liberto’ (antepasado del proletario moderno) fue la personificación social masculina clave en la génesis patriarcal del Capitalismo por el Estado, siendo la explotación psico-sexual de las mujeres (prostitución) una empresa de primer orden para la comprensión de dicha génesis. Según el Esquizoanálisis, la explotación psico-sexual y libidinal es la ratio de la explotación económica y de la dominación de clase. Por eso, no podremos abordar dicha relación genética entre Patriarcado, Estado y Capital (tocante a las violencias masculinas) sin abordar, en esta «Parte I», las críticas de Deleuze/Guattari hacia Marx/Engels: esquizo-análisis ácrata (en tanto que análisis de procesos maquínicos) versus materialismo dialéctico (en tanto que análisis de procesos dialécticos). Ahora bien, ¿acaso el materialismo dialéctico resulta operativo (en la crítica y en la clínica) a la hora de comprender y de caracterizar (y de luchar contra) las violencias psico-sexuales patriarcales masculinas, como por ejemplo, la prostitución? ¿Cómo Marx, Engels, Bebel y Riazánov caracterizaron (desde el materialismo dialéctico) tanto a la prostitución, como a la prostituta, y al prostituyente? ¿No acaban incurriendo en un reduccionismo economicista y cambista (en materia sexual) que torna invisibles las causas patriarcales de la dominación y las violencias masculinas, tornándose incluso su garante insospechado “por izquierda”? Este será el problema central de la «Parte II». Nuestro concepto social de ‘Salud Mental’ depende directamente del modo de caracterizar dichos problemas psico-sexo políticos.

Susobhan Mandal, S. Shankaranarayanan

General relativity and quantum field theory are the cornerstones of our understanding of physical processes, from subatomic to cosmic scales. While both theories work remarkably well in their tested domains, they show minimal overlap. However, our research challenges this separation by revealing that non-perturbative effects bridge these distinct domains. We introduce a novel mechanism wherein, at linear order, spin-2 fields around an arbitrary background acquire \emph{effective mass} due to the spontaneous symmetry breaking (SSB) of either global or local symmetry of complex scalar field minimally coupled to gravity. The action of the spin-2 field is identical to the extended Fierz-Pauli (FP) action, corresponding to the mass deformation parameter $α= 1/2$. We show that this occurs due to the effect of SSB on the variation of the energy-momentum tensor of the matter field, which has a dominant effect during SSB. The extended FP action has a salient feature, compared to the standard FP action: the action has 6 degrees of freedom with no ghosts. For local $U(1)$ SSB, we establish that the effective mass of spin-2 fields is related to the mass of the gauge boson and the electric charge of the complex scalar field. Interestingly, our results indicate that the millicharged dark matter scalar fields, generating dark photons, can produce a mass of spin-2 fields of the same order as the Hubble constant $(H_0)$. Hence, we argue that the dark sector offers a natural explanation for the acceleration of the current Universe.

Claudio Berríos Cavieres

El presente trabajo da cuenta de la presencia del poeta César Vallejo en la revista Amauta (1926-1930), analizando los diferentes escritos allí presentes (poemas, cuento y ensayos). En primer lugar, se establece una reflexión en torno a las vanguardias latinoamericanas, como ejemplo renovador y propio de esta experiencia en el continente. En segundo lugar, se analizan algunos poemas y ensayos de Vallejo en Amauta en relación con la problemática de vanguardia y “nueva poesía” en América Latina. Por último, se analizan los dos últimos trabajos de Vallejo y cómo ellos se insertan en los debates y programas políticos dentro de Amauta.

Paolo Graniero, Paolo Graniero, Mark Khenkin et al.

Perovskite solar cells are the most dynamic emerging photovoltaic technology and attracts the attention of thousands of researchers worldwide. Recently, many of them are targeting device stability issues–the key challenge for this technology–which has resulted in the accumulation of a significant amount of data. The best example is the “Perovskite Database Project,” which also includes stability-related metrics. From this database, we use data on 1,800 perovskite solar cells where device stability is reported and use Random Forest to identify and study the most important factors for cell stability. By applying the concept of learning curves, we find that the potential for improving the models’ performance by adding more data of the same quality is limited. However, a significant improvement can be made by increasing data quality by reporting more complete information on the performed experiments. Furthermore, we study an in-house database with data on more than 1,000 solar cells, where the entire aging curve for each cell is available as opposed to stability metrics based on a single number. We show that the interpretation of aging experiments can strongly depend on the chosen stability metric, unnaturally favoring some cells over others. Therefore, choosing universal stability metrics is a critical question for future databases targeting this promising technology.

Miguel Jaramago

Analizamos en el presente trabajo una estatua del tipo convencionalmente denominado Orante sumerio, depositada en el Museo Arqueológico Nacional (Madrid), y expuesta actualmente en sus salas de Egipto, Nubia y Oriente Próximo. Revisaremos la pieza en detalle, comentando sus características y estado de conservación, haremos una breve referencia al significado que pudo tener en la sociedad en que surgió, y finalmente nos plantearemos su posible origen geográfico y su cronología, así como ciertos elementos que tal vez podrían ser indicios de una discutible antigüedad.

Wencheng Jin, Yimin Lu, Yimin Lu et al.

The upstream of bioenergy industry has suffered from unreliable operations of granular biomass feedstocks in handling equipment. Computational modeling, including continuum-mechanics models and discrete-particle models, offers insightful understandings and predictive capabilities on the flow of milled biomass and can assist equipment design and optimization. This paper presents a benchmark study on the fidelity of the continuum and discrete modeling approaches for predicting granular biomass flow. We first introduce the constitutive law of the continuum-mechanics model and the contact law of the coarse-grained discrete-particle model, with model parameters calibrated against laboratory characterization tests of the milled loblolly pine. Three classical granular material flow systems (i.e., a lab-scale rotating drum, a pilot-scale hopper, and a full-scale inclined plane) are then simulated using the two models with the same initial and boundary conditions as the physical experiments. The close agreement of the numerical predictions with the experimental measurements on the hopper mass flow rate, the hopper critical outlet width, the material stopping thickness on the inclined plane, and the dynamic angle of repose, clearly indicates that the two methods can capture the critical flow behavior of granular biomass. The qualitative comparison shows that the continuum-mechanics model outperforms in parameterization of materials and wall friction, and large-scale systems, while the discrete-particle model is more preferred for discontinuous flow systems at smaller scales. Industry stakeholders can use these findings as guidance for choosing appropriate numerical tools to model biomass material flow in part of the optimization of material handling equipment in biorefineries.

A’am Rifaldi Khunaifi, Arif Supriyadi, Dedy Setyawan

Guru SMAN 1 Pandih Batu belum menggunakan Learning Management System (LMS) secara maksimal sehingga membutuhkan pelatihan dalam menggunakan aplikasi ini.  Tujuan kegiatan ini adalah untuk meningkatkan pemahaman guru mengenai LSM khususnya menggunakan Sevima Edlink.  Metode yang digunakan dalam pelatihan ini adalah demonstrasi, praktek, dan diskusi. Peserta pada kegiatan ini adalah 30 orang guru di SMAN 1 Pandih Batu.  Target pelatihan ini yaitu guru mampu menggunakan Sevima Edlink, pembuatan topik materi,  invite  siswa,  pengunggahan materi pelajaran, dan kuis daring. Hasil dari kegiatan ini menunjukan terjadi peningkatan kemampuan berdasarkan hasil pretest dengan nilai 62,3 meningkat pada hasil postest dengan nilai 80,5. Hasil skor N-Gain menunjukan terjadi peningkatan kemampuan guru sebesar 0,48 dengan kategori sedang. Peserta menilai bahwa pelatihan ini dapat memberikan manfaat berupa peningkatan pengetahuan dan keterampilan diri bagi peserta dengan metode ceramah maupun kegiatan demonstrasi dan peserta juga menilai bahwa pemateri baik ceramah maupun praktek sangat baik dalam penguasaan metode dan materi.

Marta Branco Guerreiro

Najeeb Ullah, Behnam Ababaei, Karine Chenu

The frequency of heat shocks during grain filling of wheat crops across the Australian wheatbelt has significantly increased over the last 30 years. These post-flowering heat events significantly reduce wheat yields with a relatively greater impact on grain size than grain number. A controlled environment study was conducted to assess the impact of post-flowering heat shocks on wheat recombinant inbred lines SB062 and SB003. Plants were submitted to 7-day heat shocks (33/21 °C day/night temperature) at different periods during grain filling. Heat shocks significantly accelerated leaf senescence, with a greater impact on older leaves and for mid post-flowering stresses. Overall, the tolerant line (SB062) could maintain leaf greenness longer than the sensitive line (SB003), especially when submitted to heat stress. Further, heat shocks during early-to-mid grain filling reduced the grain size and weight. While the impact on developing grains was significant in SB003, no significant effect of post-flowering heat was observed on leaf senescence nor on grain size in the tolerant line SB062. Delayed leaf senescence appeared to play a role in maintaining grain size under heat stress. The research findings will assist improving crop models for post-flowering heat effects and developing techniques for screening heat tolerant wheat lines. Increased post-flowering assimilate production through sustained leaf greenness could improve the performance of wheat crops in increasingly warmer environments.

Natalia A. Drovaleva

Numerous papers have been written on the topic of portrait creation in literature, viewing it both directly and indirectly, however it remains a topical issue up to this day. It is evidently necessary to systemize the data, gathered by numerous literary research on the portrait characteristics. In this regard, it appears productive to point out the theoretical and methodological particularities of researching a character’s appearance in literature, the existing research notions on the portrait in fiction literature and visual arts and the notable peculiarities of creating a character’s appearance, using examples from prose works of the Silver Age specifically. This period saw the rise of tendencies that consisted of moving away from an actual depiction of reality and the obligatory establishment of connections between external and internal features of the character. By examining various scholarly theories, the author points out that as a result of close attention to the artistic portrait, typical for the end of the 20th century, many works of that period that studied the particularities of characters’ appearance mirrored the notions about graphic and artistic portraits. Traditionally the portrait was researched in connection with the general history of art, and its depicting and artistic function was being actualized. However, it is not the primary function of the portrait, even if it could prove to be productive to research it in the case of painting writers or writing painters (for example M.A. Voloshin and K.A. Korovin). The author draws a specific conclusion that it would be impractical to distinguish a portrait as a closed integrity, and that the phrase “appearance visualization” seems to be the most fitting for describing the portrait features in works of fiction, as opposed to the literary portraits in biographical literature that portray and recreate the image of an existing person.

Leena Ahmad Alfarani, Seham Saleh Alnafea

This study aimed to identify the extent of, as well as the obstacles encountered, while using artificial intelligence technologies in enrichment programs in Saudi gifted and talented centres. A descriptive analytical approach was used and applied to a sample of 104 supervisors, managers, and teachers at these facilities. A questionnaire was employed. The results showed: 1. A response from the sample’s participants revealed that ‘the extent of using artificial intelligence technology in enrichment programs in Saudi talented centres’ reached 84.3%, indicating a strong level of approval among the members of the sample. 2. The sample’s participants’ responses showed that the ‘obstacles of artificial intelligence technology in enrichment programs in Saudi talented centres’ reached 80.2%, also indicating a strong level of agreement among the sample members. There were no statistically significant differences among the individuals using artificial intelligence techniques in the enrichment programs in the talented centres in Saudi Arabia. This is according to the following variables: the educational sector (boys and girls), the nature of the work in the talented centres, the years of experience in the field, the age of the participants, as well as the educational and academic qualifications in the fields of the participating talent.

Liliana Gonçalves

Neste trabalho, descrevemos não só as diversas formas de dar feedback aos aprendentes, neste caso chineses, após a realização de uma tarefa escrita, mas também o processo que adotámos para tornar o trabalho de correção mais eficiente e eficaz. Assim, na parte mais teórica deste estudo, abordamos o feedback dado pelos pares (colegas de turma) e o feedback que envolve o docente, não só escrito (direto e indireto), mas também face a face. Na parte prática deste trabalho, analisáamos como o ‘método’ de correção e de reescrita adotado torna o processo mais reflexivo e ponderado, verificando-se não só o melhoramento dos textos, mas também a retenção de aspetos compreendidos e corrigidos, ainda que essa retenção não seja total na maioria dos casos.

Óscar Javier Barrera Aguilera

Reseña del libro: Toledo Tello, Sonia (2019). Espacios sociales en una región agraria del norte de Chiapas (siglos XIX-XXI). San Cristóbal de Las Casas, Chiapas: CIMSUR-UNAM.

Matej Sárený

In the paper we study propagation of light in general relativity through a spacetime filled with cold plasma with infinite conductivity. We use the geometric optics based on Synge's approach. As the main result we provide a formula for calculation of spectral flux of radiation emitted from a pointlike source. The formula employs connecting vectors that are obtained by integrating the ray deviation equation along the reference ray connecting the source and observation event. As a byproduct we formulate Etherington's reciprocity theorem with the inclusion of plasma, interrelating angular size distance and luminosity distance. We also discuss the Liouville theorem and its formulation in terms of connecting vectors.

I Ketut Budaraga, Ramaiyulis Ramaiyulis, Ellyza Nurdin et al.

Jajanan, makanan dan kantin sehat sehat merupakan kebutuhan anak-anak sekolah yang punya andil besar dalam menumbuhkan generasi berprestasi kedepan. Permasalahan sekarang ini sering ketersediaan jajanan, makanan dan kantin sehat kurang tersedia khususnya di sekolah SMA 2 Batang Anai sehingga perlu dilakukan penyuluhan. Tujuan kegiatan penyuluhan ini memberikan informasi masalah jajanan,makanan dan kantin sehat kepada anak-anak sekolah, pengelola kantin masyarakat sekitar sekolah yang berjualan di sekolah. Metode yang digunakan menggunakan metode ceramah dan tanya jawab (diskusi). Kegiatan diadakan aula SMA 2 Batang Anai pada tanggal 7 Januari 2019 diikuti oleh 30 peserta. Hasil penyuluhan menunjukkan peserta sangat antosias mengikuti kegiatan ini sampai selesai. Harapan peserta agar kegiatan ini berlanjut secara terus menerus setiap awal tahun. Kata kunci : Penyuluhan, jajanan, makanan, sehat, sekolah

Daniel Blixt, Manuel Hohmann, Martin Krššák et al.

It is known that one can formulate an action in teleparallel gravity which is equivalent to general relativity, up to a boundary term. In this geometry we have vanishing curvature, and non-vanishing torsion. The action is constructed by three different contractions of torsion with specific coefficients. By allowing these coefficients to be arbitrary we get the theory which is called `new general relativity'. In this note, the Lagrangian for new general relativity is written down in ADM-variables. In order to write down the Hamiltonian we need to invert the velocities to canonical variables. However, the inversion depends on the specific combination of constraints satisfied by the theory (which depends on the coefficients in the Lagrangian). It is found that one can combine these constraints in 9 different ways to obtain non-trivial theories, each with a different inversion formula.

Johan Bengtsson

In 1945 Einstein concluded that [1]: "The present theory of relativity is based on a division of physical reality into a metric field (gravitation) on the one hand, and into an electromagnetic field and matter on the other hand. In reality space will probably be of a uniform character and the present theory be valid only as a limiting case. For large densities of field and of matter, the field equations and even the field variables which enter into them will have no real significance.". The dichotomy is resolved by introducing a complex Randers metric with a real valued scalar field and complex valued vector field, providing a unified mathematical framework for gravitation & electromagnetism for which the resulting theory's predictions agree with General Relativity; to leading order in the gravitational constant. Hence, the related experimental results validate both theories; and the former theory's metric solutions are free of spurious singularities, because its stress-energy tensor includes the energy & momentum for the gravitational field; like e.g. Maxwell's stress-energy tensor contains the electromagnetic field.