Optimal Capital Income Taxation in a Two-Sector Economy

We extend the celebrated Chamley-Judd result of zero capital income tax and show that the steady state optimal capital income tax is nonzero, in general. In particular, we find that the optimal plan involves zero capital income tax in investment sector and a nonzero capital income tax in consumption sector. In a two sector neoclassical economy, interdependence of labour and capital margins allows the government to choose an optimal policy that involves nonzero tax on capital income. The distortion created by capital income tax in consumption sector can be undone by setting different rates of labour income taxes. The optimal plan thus involves zero capital income tax in both sectors only if optimal labour income taxes are equal. This may not be the optimal policy if marginal disutility of work is different across sectors and/or the social marginal value of capital is different across sectors. The difference in social marginal value of capital can be undone by setting different labour income taxes across sectors. We also show that if the government faces a constraint of keeping same capital and labour income tax rates across sectors, optimal capital income tax is nonzero

On Policy Relevance of Ramsey Tax Rules

The Ramsey approach to optimal taxation and Ramsey tax rules have amassed substance in economic theory. However, they are often criticized on grounds of practicality, fairness, feasibility and some other aspects of designing actual tax policy. This paper presents a collection of these views; it discusses how closely or remotely Ramsey rules are followed in designing tax policy. It presents some recent tax reforms in the US and in the UK that have closely, if not completely, followed the principle of distortion minimization. Despite the widely speculated difficulty associated with mapping normative tax rules into positive policy design, it is possible to implement taxes that have strong correspondence to Ramsey tax formulas. This paper also discusses why some implemented tax rules lack onsistency with Ramsey principles, or why it is often difficult to establish correspondence between some implemented taxes and Ramsey tax rules

Effects of initial compression stress on wave propagation in carbon nanotubes

An analytical method to investigate wave propagation in single- and double- walled carbon nanotubes under initial compression stress is presented. The nanotube structures are treated within the multilayer thin shell approximation with the elastic properties taken to be those of the graphene sheet. The governing equations are derived based on Flugge equations of motion. Frequency equations of wave propagation in single and double wall carbon nanotubes are described through the effects of initial compression stress and van der Waals force. To show the effects of Initial compression stress on the wave propagation in nanotubes, the symmetrical mode can be analyzed based on the present elastic continuum model. It is shown that the wave speed are sensitive to the compression stress especially for the lower frequencies.Comment: 12 pages, 4 figure

A bound for the eigenvalue counting function for Krein--von Neumann and Friedrichs extensions

For an arbitrary open, nonempty, bounded set $\Omega \subset \mathbb{R}^n$, $n \in \mathbb{N}$, and sufficiently smooth coefficients $a,b,q$, we consider the closed, strictly positive, higher-order differential operator $A_{\Omega, 2m} (a,b,q)$ in $L^2(\Omega)$ defined on $W_0^{2m,2}(\Omega)$, associated with the higher-order differential expression $$\tau_{2m} (a,b,q) := \bigg(\sum_{j,k=1}^{n} (-i \partial_j - b_j) a_{j,k} (-i \partial_k - b_k)+q\bigg)^m, \quad m \in \mathbb{N},$$ and its Krein--von Neumann extension $A_{K, \Omega, 2m} (a,b,q)$ in $L^2(\Omega)$. Denoting by $N(\lambda; A_{K, \Omega, 2m} (a,b,q))$, $\lambda > 0$, the eigenvalue counting function corresponding to the strictly positive eigenvalues of $A_{K, \Omega, 2m} (a,b,q)$, we derive the bound $$N(\lambda; A_{K, \Omega, 2m} (a,b,q)) \leq C v_n (2\pi)^{-n} \bigg(1+\frac{2m}{2m+n}\bigg)^{n/(2m)} \lambda^{n/(2m)} , \quad \lambda > 0,$$ where $C = C(a,b,q,\Omega)>0$ (with $C(I_n,0,0,\Omega) = |\Omega|$) is connected to the eigenfunction expansion of the self-adjoint operator $\widetilde A_{2m} (a,b,q)$ in $L^2(\mathbb{R}^n)$ defined on $W^{2m,2}(\mathbb{R}^n)$, corresponding to $\tau_{2m} (a,b,q)$. Here $v_n := \pi^{n/2}/\Gamma((n+2)/2)$ denotes the (Euclidean) volume of the unit ball in $\mathbb{R}^n$. Our method of proof relies on variational considerations exploiting the fundamental link between the Krein--von Neumann extension and an underlying abstract buckling problem, and on the distorted Fourier transform defined in terms of the eigenfunction transform of $\widetilde A_{2} (a,b,q)$ in $L^2(\mathbb{R}^n)$. We also consider the analogous bound for the eigenvalue counting function for the Friedrichs extension $A_{F,\Omega, 2m} (a,b,q)$ in $L^2(\Omega)$ of $A_{\Omega, 2m} (a,b,q)$. No assumptions on the boundary $\partial \Omega$ of $\Omega$ are made.Comment: 39 pages. arXiv admin note: substantial text overlap with arXiv:1403.373

Liberalization, bankers’ motivation and productivity: a simple model with an application

Proponents of financial liberalization argue that deregulation motivates bankers to increase their effort and operate at a higher level of efficiency and productivity. Sceptics, however, see that liberalization engenders economic instability and banking crises, and impedes growth. Bank efficiency and productivity, following liberalization, is extensively examined. Nonetheless, the core issue of bankers’ self-motivation remains implicitly assumed and unaddressed. Does liberalization self-motivate bankers and increase their efforts and productivity? This paper models bank productivity from this perspective and evaluates what proportion of banks’ total factor productivity is accounted for by the self-motivated productivity of bankers. We provide a micro-founded framework for the analyses of bankers’ optimal level of effort and effort-driven productivity. Our model also captures banks’ unit input-output prices, optimal wages, bank spread and the overall cost of bank services – measures that are important in evaluating reform policies. We assess the financial liberalization of Nepal as a test case and find that (i) bankers’ efforts and productivity have notably improved in Nepal, although banking services have become costly, and (ii) bank spread has moderately declined in recent years. Our approach is parametric which differs from DEA, hence complements the literature. We hope this analytical framework will be useful to evaluate reform episodes elsewhere

Regeneration of begonia plantlets by direct organogenesis

The economic importance of ornamentals worldwide suggests a bright future for ornamental breeding. Rapid progress in plant molecular biology has great potentials to contribute to the breeding of novel ornamental plants utilizing recombinant DNA technology. The plant cell, tissue or organ culture of many ornamental species and their regeneration are essential for providing the material and systems for their genetic manipulation, and this is therefore the first requirement of genetic engineering. In this research, different concentration of BA (0.0, 0.5, 1.0, 2.0 mgl(-1) with NAA ( 0.0, 0.5, 1.0 mgl(-1)) and BA (0.0, 0.5, 1.0, 2.0 mgl(-1)) with IAA ( 0.0, 0.5, 1.0, mgl(-1)) were investigated to optimize regeneration of Begonia elatior cv. Toran orange. The best regeneration and growth were obtained from the media containing 2.0 mgl(-1) BA and 1.0 mgl(-1) NAA (70%) followed by 1.0 mgl(-1) BA and 0.5 mgl(-1) NAA (50%), 1.0 mgl(-1) BA and 1.0 mgl(-1) NAA (20%) in BA - NAA combination. The media with BA - IAA combination showed that the best regeneration was 0.5 mgl(-1) BA and 0.5 mgl(-1) IAA (43%) followed by 0.5 mgl(-1) BA and 1.0 mgl(-1) IAA (23%)

Mobil haberleşme combo antenleri için genişband elektromanyetik sönümlendirici

Mobile network operators (MNOs) have to sustain the interworking of different generations of mobile technologies in different frequency bands. On the other hand, electromagnetic (EM) pollution, which is caused mainly by the mobile devices and mobile network base stations, also raises public health concerns. Thus, MNOs use combo antennas, which encapsulate multiple antenna rods in a single radome. In this study, the authors propose a broadband electromagnetic absorber for the mobile network base station (BS) combo antennas. They have merged the multi-layer Jaumann absorber (JA) and Salisbury screen principles along with the merits of off-the-shelf micrometric and millimetric graphite and nanometric carbon black. Advanced silver and nickel coated nanometric cenospheres were also used to decrease the absorber thickness and to improve EM scattering and absorption. And finally, silver fabric was used as the salisbury screen with novel perpendicular threads into the absorber body as heat sink. After the laboratory tests, the absorber has also been tested in the field. The application of the absorber has reduced the unwanted radio frequency (RF) signal around 18 dB in the tested frequency range without any network affecting disturbances or without any noticeable antenna pattern deformation with only a thickness of ninety millimeters. Such an absorber may also help containing the unwanted spread of electromagnetic waves from BS antennas; and, in return, decrease the overall mobile network RF noise and electromagnetic pollution both in uplink and downlink frequency bands.Mobil Şebeke İşletmecileri (MŞİ) farklı jenerasyon mobil teknolojilerinin farklı sıklık aralıklarında düzgün çalışmasını sağlamak zorundadırlar. Öte yandan, elektromanyetik (EM) kirlilik, ki daha çok mobil telefonlar ve mobil baz istasyonları tarafından kaynaklanır, toplumda sağlık kaygıları yaratmaktadır. Bu sebeple, MŞİler birçok anten çubuğunu tek bir radomeda saklayan combo antenleri kullanmaktadırlar. Bu çalışmada, araştırmacılar mobil şebeke baz istasyonu combo antenleri için genişband bir elektromanyetik sönümlendirici önermektedirler. Araştırmacılar bunun için çok katmanlı Jaumann sönümlendirme (JS) ve Salisbury ekranlama prensiplerini mikrometrik ve milimetrik grafit ve nonametrik karbon siyahı malzemeleri üzerine uygulamıştır. Buna ek olarak, ileri teknoloji gümüş ve nikel kaplanmış seramik kürecikler de sönümlendirici kalınlığını azaltmak üzere EM saçılımını arttırmak ve sönümlenmeyi iyileştirmek için kullanılmıştır. Son olarak, gümüş kaplı naylon kumaş da salisbury ekranlamasının en yenilikçi şekli ile sönümlendiriciye dik iplikçiklerle yerleştirilerek ısınma sorununu çözmüştür. Laboratuvar testlerinden sonra, sönümlendirici sahada test edilmiştir. Doksan milimetre kalınlığındaki bir sönümlendirici uygulaması istenmeyen radyo frekans (RF) sinyalini mobil şebekenin çalışmasını engellemeden ve anten yayınım şeklini değiştirmeden 18 dB azalmiştir. Bu tip bir sönümlendirici istenmeyen elektromanyetik dalgaların yayılmasını engellemeye yardımcı olabilir ve bütün mobil şebeke RF gürültüsünü ve EM kirliliğini her iki yayın yönünde de azaltabilir