10,240 research outputs found
A density-functional theory investigation of cluster formation in an effective-potential model of dendrimers
We consider a system of particles interacting via a purely repulsive,
soft-core potential recently introduced to model effective pair interactions
between dendrimers, which is expected to lead to the formation of crystals with
multiple occupancy of the lattice sites. The phase diagram is investigated by
density-functional theory (DFT) without making any a priori assumption on the
functional form of the density profile or on the type of crystal lattice. As
the average density is increased, the system displays first a transition
from a fluid to a bcc phase, and subsequently to hcp and fcc phases. In the
inhomogeneous region, the behavior is that found in previous investigations of
this class of cluster-forming potentials. Specifically, the particles arrange
into clusters strongly localized at the lattice sites, and the lattice constant
depends very weakly on , leading to an occupancy number of the sites
which is a nearly linear function of . These results are compared to
those predicted by the more widespread approach, in which the DFT minimization
is carried out by representing the density profile by a given functional form
depending on few variational parameters. We find that for the model potential
studied here, the latter approach recovers most of the predictions of the
unconstrained minimization.Comment: 22 pages, 7 figures. To appear in a Festschrift Issue of Transactions
of The Royal Norwegian Society of Sciences and Letters (DKNVS) dedicated to
Johan Hoye on his 70th birthda
Global business and human rights: the UN ânorms on the responsibility of transnational corporations and other business enterprises with regard to human rightsâ - a requiem
On 11 June 2011, the United Nations Human Rights Council endorsed the âGuiding Principles for Business and Human Rightsâ as a new set of guiding principles for global business designed to provide a global standard for preventing and addressing the risk of adverse impacts on human rights linked to business activity. This outcome was preceded by an earlier unsuccessful attempt by a Sub-Commission of the UN Commission on Human Rights to win approval for a set of binding corporate human rights norms, the so called âNorms on the Responsibilities of Transnational Corporations and Other Business Enterprises with Regard to Human Rightsâ. This article identifies and discusses the reasons why the Norms eventually failed to win approval by the then UN Commission on Human Rights. This discussion is important in order to understand the difficulties in establishing binding âhard lawâ obligations for Transnational Corporations with regard to human rights within the wider framework of international law. It is crucial to understand possible motives as well as the underlying rationale which lead first to the adoption and then the rapid abandoning of the Norms: such a discussion will also shed light on the prospects and trends of concepts of indirect, vague voluntarism of business human rights compliance, as well as on prospects of finding alternative solutions, and finally the rationale and effect of the âGuiding Principles for Business and Human Rightsâ
Penerapan Metode Karya Wisata Untuk Meningkatkan Kemampuan Berbahasa Pada Anak TK A TK Negeri Pembina Nganjuk Tahun 2017
Penelitian ini dilatarbelakangi oleh kemampuan anak dalam berbahasa khusunya berbicara yang kurang berkembang secara maksimal.Hal ini karena kurangnya variasi metode yang digunakan guru dalam pembelajaran berbahasa.Metode karyawisata merupakan cara pembelajaran yang membawa atau mengikut sertakan anak untuk mengunjungi suatu tempat diluar kelas secara langsung guna mempelajari, mengamati, suatu obyek secara langsung sesuai dengan keadaan yang sesungguhnya. Metode ini merupakan salah satu metode yang dapat digunakan untuk mengembangkan kemampuan berbahasa. Tujuan dari penelitian ini adalah untuk mengetahui pengaruh metode karya wisata terhadap kemampuan berbahasa pada anak TK A, TKNegeri Pembina Nganjuk Kec.Nganjuk Kab Nganjuk, tahun 2017.Penelitian ini menggunakan rancangan Penelitian Tindakan Kelas dengan menggunakan metode karyawisata untuk mengembangkan kemampuan berbahasa anak dengan mengikuti alur pokok 2 siklus :siklus pertama merupakan identifikasi masalah, dilanjutkan alternative pemecahan masalah dan rencana tindakan, pelaksanaan tindakan, kemudian diobservasidan dianalisa terakhir penulis akan melakukan refleksi, dan dilanjutkan pada siklus berikutnya.Penelitian ini dilaksanakan di TK Negeri Pembina Nganjuk Kab.Nganjuk, tahun 2018. Dari hasil analisis data dengan penerapan metode karyawisata sangat baik untuk metode pendidikan di TK Negeri Pembina Nganjuk ,Kab.Nganjuk, diperoleh hasil ketuntasan kemampuan berbahasa dari 15 anak diperoleh 13 anak telah mencapai ketuntasan kemampuan. Hal ini mencapai tingkat ketuntasan yaitu 86,67% melampaui tingkat ketuntasanyang diharapkan yaitu75%, karena pada umumnya anak usia TK gemar melihat langsung dan mendengarkan cerita yang disampaikan baik oleh guru, kakak maupun ibunya. Dan guru harus mampu mengupayakan ada nya interaksi dengan siswa, dengan demikian maka akan membiasakan anak berbicara, yang mana pada akhirnya akan membiasakan anak berani mengungkapkan fikiranya dengan bahasa
Aspects of the moduli space of instantons on and its orbifolds
We study the moduli space of self-dual instantons on . These
are described by an ADHM-like construction which allows to compute the Hilbert
series of the moduli space. The latter has been found to be blind to certain
compact directions. In this paper we probe these, finding them to correspond to
a Grassmanian, upon considering appropriate ungaugings. Moreover, the ADHM-like
construction can be embedded into a gauge theory with a known gravity
dual. Using this, we realize in (part of) the instanton moduli
space providing at the same time further evidence supporting the
duality. Moreover, upon orbifolding, we provide the ADHM-like construction of
instantons on as well as compute its Hilbert
series. As in the unorbifolded case, these turn out to coincide with those for
instantons on .Comment: 65 page
Self-consistent Ornstein-Zernike approximation for three-dimensional spins
An Ornstein-Zernike approximation for the two-body correlation function
embodying thermodynamic consistency is applied to a system of classical
Heisenberg spins on a three-dimensional lattice. The consistency condition
determined in a previous work is supplemented by introducing a simplified
expression for the mean-square fluctuations of the spin on each lattice site.
The thermodynamics and the correlations obtained by this closure are then
compared with approximants based on extrapolation of series expansions and with
Monte Carlo simulations. The comparison reveals that many properties of the
model, including the critical temperature, are very well reproduced by this
simple version of the theory, but that it shows substantial quantitative error
in the critical region, both above the critical temperature and with respect to
its rendering of the spontaneous magnetization curve. A less simple but
conceptually more satisfactory version of the SCOZA is then developed, but not
solved, in which the effects of transverse correlations on the longitudinal
susceptibility is included, yielding a more complete and accurate description
of the spin-wave properties of the model.Comment: 32 pages, 12 figure
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