1,822 research outputs found
Evaluation of agricultural ecosystem services in fallowing land based on farmers' participation and model simulation
Fallowing with green fertilizer can benefit agricultural ecosystem services (AES). Farmers in Taiwan do not implement fallow practices and plant green fertilizer because the current subsidy level (46,000 NTperha)istoolowtomanagefallowingThispaperdefinestheobjectiveofgovernmentagriculturepolicyorthefarmer’sobjectiveasmaximizationoffarmproductivityapproximatedtothevalueofsocialwelfareandAESFarmswhichdonotfollowproperfallowingpracticesoftenhavepoorlymaintainedfallowlandorleftfarmlandabandonedThisresultsinnegativeenvironmentalconsequencessuchascutworminfestationsinabandonedlandwhichinturncanaffectcropsinadjacentfarmlandsTheobjectivesofthisstudyaretwofoldFirstitdeterminestheproperfallowingsubsidybasedontheconceptofpaymentforecosystemservicestoenticemorefarmerstoparticipateinfallowingSeconditsimulatesthebenefitofplantinggreenmanureinfallowlandtothesupplyofAESbasedontherateoffarmerswhoarewillingtoparticipateinfallowlandpracticesandessentialparametersthatcanaffectsoilfertilitychangeTheapproachinvolvesaseriesofinterviewsandadevelopedempiricalmodelThevalueofAESwhentherateoffarmerparticipationis100 ) over the value at the current participation rate of 14%. This study further concludes that the appropriate fallowing subsidy has a large positive impact on AES and social welfare (e.g., benefit from food and biofuel supplies) and is seen as a basis of ecological governance for sustainable agro-ecosystems
Shaping citizenship in the classroom:Peer influences on moral disengagement, social goals, and a sense of peer community
Despite the important role of peers in the social process of classroom citizenship, the peer influence related to moral disengagement, social goals, and a sense of peer community remain unclear. To this end, it was examined to what extent youth become similar to their friends in moral disengagement, social goals, and a sense of peer community. Participants were 283 South Korean third to sixth graders (Mage = 9.60 years, SD = 0.97; 51.6% girls) who completed an online survey for moral disengagement, social goals, the sense of peer community and friendship network across the beginning (Time 1) and end (Time 2) of the school semester (September to December). Longitudinal social network analyses indicated that youth became more similar to their friends concerning moral disengagement and a sense of peer community, but did not select friends based on these aspects. The strength of these influence effects varied in terms of different levels of these aspects. Specifically, youth were more likely to become similar to their friends at lower levels of moral disengagement. Youth tended to be similar to the friends' level of sense of peer community. This tendency was relatively strong at the lowest and the highest levels of a sense of peer community. Future research should address the role of friendship in shaping classroom citizenship and the importance of classroom daily teaching practice in youth citizenship development
On the Couplings of Vector Mesons in AdS/QCD
We address, in the AdS/CFT context, the issue of the universality of the
couplings of the rho meson to other hadrons. Exploring some models, we find
that generically the rho-dominance prediction f_\rho g_{\rho H H}=m_\rho^2 does
not hold, and that g_{\rho H H} is not independent of the hadron H. However, we
prove that, in any model within the AdS/QCD context, there are two limiting
regimes where the g_{\rho H H}, along with the couplings of all excited vector
mesons as well, become H-independent: (1) when H is created by an operator of
large dimension, and (2) when H is a highly-excited hadron. We also find a
sector of a particular model where universality for the rho coupling is exact.
Still, in none of these cases need it be true that f_\rho g_\rho=m_\rho^2,
although we find empirically that the relation does hold approximately (up to a
factor of order two) within the models we have studied.Comment: 28 pages, 3 figures. ver 2: Comments about the commutability of two
universal limits in the D3/D7 case corrected. Typos corrected. ver 3:
Substantive revisions of certain calculations, with improved conventions,
correction of typos, clarifications, new formulas, new figures; no changes in
essential results or conclusion
Vertex functions for d-wave mesons in the light-front approach
While the light-front quark model (LFQM) is employed to calculate hadronic
transition matrix elements, the vertex functions must be pre-determined. In
this work we derive the vertex functions for all d-wave states in this model.
Especially, since both of and are mesons, the Lorentz
structures of their vertex functions are the same. Thus when one needs to study
the processes where is involved, all the corresponding formulas for
states can be directly applied, only the coefficient of the vertex
function should be replaced by that for . The results would be useful
for studying the newly observed resonances which are supposed to be d-wave
mesons and furthermore the possible 2S-1D mixing in with the LFQM.Comment: 12 pages, 2 figures, some typos corrected and more discussions added.
Accepted by EPJ
Going abroad: HR policies, national IR systems, and union activity in foreign subsidiaries of U.S. multinationals
Industrial and Labor Relations Review6651149-117
The rare top quark decays in the topcolor-assisted technicolor model
We consider the rare top quark decays in the framework of topcolor-assisted
technicolor (TC2) model. We find that the contributions of top-pions and
top-Higgs predicted by the TC2 model can enhance the SM branching ratios by as
much as 6-9 orders of magnitude. i.e., in the most case, the orders of
magnitude of branching ratios are , , . With the reasonable values of the
parameters in TC2 model, such rare top quark decays may be testable in the
future experiments. So, rare top quark decays provide us a unique way to test
TC2 model.Comment: 14 pages, 4 figure
The creation of large photon-number path entanglement conditioned on photodetection
Large photon-number path entanglement is an important resource for enhanced
precision measurements and quantum imaging. We present a general constructive
protocol to create any large photon number path-entangled state based on the
conditional detection of single photons. The influence of imperfect detectors
is considered and an asymptotic scaling law is derived.Comment: 6 pages, 4 figure
Interpolating between low and high energy QCD via a 5D Yang-Mills model
We describe the Goldstone bosons of massless QCD together with an infinite
number of spin-1 mesons. The field content of the model is SU(Nf)xSU(Nf)
Yang-Mills in a compact extra-dimension. Electroweak interactions reside on one
brane. Breaking of chiral symmetry occurs due to the boundary conditions on the
other brane, away from our world, and is therefore spontaneous. Our
implementation of the holographic recipe maintains chiral symmetry explicit
throughout. For intermediate energies, we extract resonance couplings. These
satisfy sum rules due to the 5D nature of the model. These sum rules imply,
when taking the high energy limit, that perturbative QCD constraints are
satisfied. We also illustrate how the 5D model implies a definite prescription
for handling infinite sums over 4D resonances. Taking the low energy limit, we
recover the chiral expansion and the corresponding non-local order parameters.
All local order parameters are introduced separately.Comment: Corresponds to published version, with some typos correcte
Density functional theory of phase coexistence in weakly polydisperse fluids
The recently proposed universal relations between the moments of the
polydispersity distributions of a phase-separated weakly polydisperse system
are analyzed in detail using the numerical results obtained by solving a simple
density functional theory of a polydisperse fluid. It is shown that universal
properties are the exception rather than the rule.Comment: 10 pages, 2 figures, to appear in PR
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