Ricci-flat Metrics with U(1) Action and the Dirichlet Boundary-value Problem in Riemannian Quantum Gravity and Isoperimetric Inequalities

The Dirichlet boundary-value problem and isoperimetric inequalities for positive definite regular solutions of the vacuum Einstein equations are studied in arbitrary dimensions for the class of metrics with boundaries admitting a U(1) action. We show that in the case of non-trivial bundles Taub-Bolt infillings are double-valued whereas Taub-Nut and Eguchi-Hanson infillings are unique. In the case of trivial bundles, there are two Schwarzschild infillings in arbitrary dimensions. The condition of whether a particular type of filling in is possible can be expressed as a limitation on squashing through a functional dependence on dimension in each case. The case of the Eguchi-Hanson metric is solved in arbitrary dimension. The Taub-Nut and the Taub-Bolt are solved in four dimensions and methods for arbitrary dimension are delineated. For the case of Schwarzschild, analytic formulae for the two infilling black hole masses in arbitrary dimension have been obtained. This should facilitate the study of black hole dynamics/thermodynamics in higher dimensions. We found that all infilling solutions are convex. Thus convexity of the boundary does not guarantee uniqueness of the infilling. Isoperimetric inequalities involving the volume of the boundary and the volume of the infilling solutions are then investigated. In particular, the analogues of Minkowski's celebrated inequality in flat space are found and discussed providing insight into the geometric nature of these Ricci-flat spaces.Comment: 40 pages, 3 figure

\bbbc P^2 and \bbbc P^{1} Sigma Models in Supergravity: Bianchi type IX Instantons and Cosmologies

We find instanton/cosmological solutions with biaxial Bianchi-IX symmetry, involving non-trivial spatial dependence of the \bbbc P^{1}- and \bbbc P^{2}-sigma-models coupled to gravity. Such manifolds arise in N=1, $d=4$ supergravity with supermatter actions and hence the solutions can be embedded in supergravity. There is a natural way in which the standard coordinates of these manifolds can be mapped into the four-dimensional physical space. Due to its special symmetry, we start with \bbbc P^{2} with its corresponding scalar Ansatz; this further requires the spacetime to be $SU(2) \times U(1)$-invariant. The problem then reduces to a set of ordinary differential equations whose analytical properties and solutions are discussed. Among the solutions there is a surprising, special-family of exact solutions which owe their existence to the non-trivial topology of \bbbc P^{2} and are in 1-1 correspondence with matter-free Bianchi-IX metrics. These solutions can also be found by coupling \bbbc P^{1} to gravity. The regularity of these Euclidean solutions is discussed -- the only possibility is bolt-type regularity. The Lorentzian solutions with similar scalar Ansatz are all obtainable from the Euclidean solutions by Wick rotation

Studi Eksperimen Aliran Melintasi Silinder Sirkular Tunggal Dengan Bodi Pengganggu Berbentuk Silinder Yang Tersusun Tandem Dalam Saluran Sempit Berpenampang Bujur Sangkar

Dalam beberapa aplikasi dunia teknik, bluff body ditempatkan di dalam saluran dengan berbagai pengaturan, misalkan saja penempatan sebuah silinder dengan diameter kecil sabagai pengontrol aliran sebelum melewati bluff body utama. Hal tersebut biasanya dilakukan untuk mengurangi atau mereduksi gaya yang diakibatkan fluida pada bluff body utama. Gaya-gaya yang ditimbulkan antara lain gaya geser, gaya normal, dan gaya hambat. Adapun penggunaan saluran sempit turut mempengaruhi karakteristik fluida. Hal ini yang mendasari adanya eksperimen aliran fluida melintasi silinder sirkular dengan bodi pengganggu ditempatkan di depannya dalam saluran sempit.Penelitian ini bertujuan untuk mempelajari aliran yang melintasi silinder sirkular dalam saluran sempit. Penelitian ini juga melihat pengaruh sebuah bodi pengganggu, yang memiliki rasio d/D=0.16, terhadap reduksi gaya drag yang dapat dilihat dari penurunan pressure drop. Variasi dalam eksperimen ini adalah rasio jarak gap L/D=1.0; 1.5; 2.0; 2.5; 3.0; 3.5; 4.0. Penelitian ini dilakukan secara eksperimental dengan cara meletakkan susunan bodi pengganggu (d=4mm) di depan silinder sirkular (D=25mm) dalam saluran sempit berpenampang bujur sangkar (h=125mm). Pengujian dilakukan di dalam wind tunnel dengan bilangan Reynolds sebesar 1 ×105, 1.28 × 105dan 1.56 × 105. Hasil eksperimen diperoleh adalah Karakteristik aliran berupa pressure drop (∆P) .Dari data tersebut dapatterlihat pengaruh bodi pengganggu terhadap pressure drop

Evaluasi Rasio Keuangan Dan Metode Economic Value Added (Eva) Guna Penilaian Kinerja Keuangan Perusahaan (Studi Pada PT. Hm. Sampoerna, Tbk Dan PT. Gudang Garam, Tbk Ysng Terdaftar Di Bursa Efek Indonesia Periode Tahun 2011 – 2013)

This study aims to determine the financial performance of the company\u27s financial PT. HM Sampoerna and PT Gudang Garam year period 2011-2013 based on the analysis of financial ratios and the Economic Value Added as well as to determine the differences between the financial performance of the company\u27s financial ratio analysis by the method of EVA. This study took two tobacco companies of all cigarette companies listed on the Stock Exchange for the sample, namely PT. HM Sampoerna and PT. Gudang Garam. The results of this study showed that based on the analysis of financial ratios, each maisng ratios contained in the financial ratios indicate that the financial performance of PT. HM Sampoerna is much better than the financial performance of PT. Gudang Garam. The calculation of EVA method to determine the financial performance, it is known that from each of the components contained in the EVA method showed that the financial performance of PT. HM Sampoerna is also better than the financial performance of PT. Gudang Garam. Measurement of financial ratio analysis as well as by using EVA has the same end result, namely PT. HM Sampoerna, which has a better financial performance than PT. Gudang Garam

Convergence or disparity? A cross-country analysis of corporate social responsibility reporting for banking industry in Nordic countries and China

This research investigates the corporate social responsibility (CSR) reporting for banking industry in Nordic countries and China, and compares the convergence and disparity of disclosed CSR information across these two regimes. The study encompasses a sample of eight largest commercial banks by total assets in Nordic countries and China over a 5-year period of 2013–2017. We employ a disclosure index approach to assess the contents of CSR reporting based on eight categories and a total of 60 CSR indicators. The results indicate that Nordic banks have a higher overall disclosure level of CSR information than Chinese banks, and significantly ahead of their counterparts with respect to the international commitment, and a wider coverage of addressing stakeholders’ needs. In contrast, CSR reporting in Chinese banks put greater emphasis on national public policy and philanthropic activities. Nevertheless, all sample countries share a convergence on underlining the importance of complying with applicable laws and regulations. The study findings assert that the convergence and disparity of CSR reporting across countries is relevant to pre-existing socio-political institutions the firms can rely on. This research probes into an unexplored research territory by comparing the CSR reporting between banks from a so-called Nordic business-society model and a Confucian-tradition model. Hence, it entails some important policy prescriptions for the concerned administrators and corporate practitioners in the sample countries.info:eu-repo/semantics/publishedVersio

Correlation between Leptin with Diastolic Function in Young Adult Obesity

Background: Obesity is one of the global health problems with increasing prevalence, and the complication is related to the alteration of the left ventricle. An obese person without symptoms has impaired diastolic function compares to a normal population, but the mechanism is still unclear. One of the evolving theories is caused by chronic inflammation, characterized by the increase of proinflammatory adipocytokines in an obese person. Leptin is a chronic inflammatory marker which is synthesized by all adipose tissues and has a positive correlation with the body mass index. Leptin level are influenced by age except young adult group. The aim of this study is to investigate the correlation between leptin level and diastolic function of the left ventricle in youngadult obese.Method: This study was conducted in a single centre with cross-sectional design. The subject of this study consists of all young adult obese, worked in Dr. Hasan Sadikin General Hospital, between June-August 2018. The diastolic function of the left ventricle was measured by examining the ventricle relaxation (E/mean e’) by tissue doppler imaging method. The examination of leptin level was done by sandwich-ELISA testmethod. Pearson correlation test was done to assess the correlation between those two.Result: This study consisted of 38 patients with the mean of age 30.75±7.25 years old, 68% were males. The mean score of E/mean e’ was 6.49±3.02 ng/mL and the median of leptin was 13.95 (9.1–25.4) mg/L. After data log transformation of leptin was done, there was a significant positive correlation (r= 0.5892, p<0.001) between leptin level and E/mean e’.Conclusion: There was a significant correlation between the level of leptin and diastolic function of the left ventricle in young adult obese

Nuttier (A)dS Black Holes in Higher Dimensions

We construct new solutions of the vacuum Einstein field equations with cosmological constant. These solutions describe spacetimes with non-trivial topology that are asymptotically dS, AdS or flat. For a negative cosmological constant these solutions are NUT charged generalizations of the topological black hole solutions in higher dimensions. We also point out the existence of such NUT charged spacetimes in odd dimensions and we explicitly construct such spaces in 5 and 7 dimensions. The existence of such spacetimes with non-trivial topology is closely related to the existence of the cosmological constant. Finally, we discuss the global structure of such solutions and possible applications in string theory.Comment: latex, 30 pages, added reference

Generalized Second Law of Thermodynamics in Extended Theories of Gravity

By employing the general expression of temperature $T_{h}=|\kappa|/2\pi = \frac{1}{2\pi \tilde{r}_{A}}(1-\frac{\dot{\tilde{r}}_{A}}{2H\tilde{r}_{A}})$ associated with the apparent horizon of a FRW universe and assuming a region of FRW universe enclosed by the apparent horizon as a thermal system in equilibrium, we are able to show that the generalized second law of thermodynamics holds in Gauss-Bonnet gravity and in more general Lovelock gravity.Comment: 10 page