Addendum to Finite-size effects on multibody neutrino exchange

The interaction energy of the neutrons due to massless neutrino exchange in a neutron star has recently been proved, using an effective theory, to be extremely small and infrared-safe. Our comment here is of conceptual order: two approaches to compute the total interaction energy density have recently been proposed. Here, we study the connection between these two approaches. From CP invariance, we argue that the resulting interaction energy has to be even in the parameter $b=-G_F n_n /\sqrt{2}$, which expresses the static neutrino potential created by a neutron medium of density $n_n$.Comment: Latex file (Revtex), 9 pages, 1 figure, one reference change

Turboelectric Distributed Propulsion System for NASA Next Generation Aircraft

Next generation aircraft, more specifically NASA aircraft concepts, will include new technologies and make many advancements in fuel economy and noise. However, there are some challenges associated with the latest technologies that NASA is planning to use for the next generation aircraft. For example, these aircraft concepts require large amounts of electrical power to generate the required thrust throughout a notional flight profile. One of the new technologies is using advanced propulsion systems, such as the Turboelectric Distributed Propulsion (TeDP) system, which is significantly different from current aerospace high bypass turbofan based propulsion system. The TeDP propulsion system replaces the traditional turbofan engines with a series of embedded electrical fans. The blended wing body aircraft, N3-X (Boeing 777 class), that NASA proposed will have as many as 14 electric fans mounted on the upper aft surface of the aircraft wings. In addition to improved aircraft efficiency, this propulsion system change will significantly reduce noise generation, and provide the capability of short take-off and landing. A dynamic model of the ducted fan distributed propulsion system was developed and simulated for different notional flight profiles. The results show that the ducted fan distributed propulsion system dynamic model and the control system successfully generate the required thrust for the flights and capture the transient behavior of the system throughout the flight profiles. In addition, the dynamic model was used to model a 50 passenger regional aircraft. This study shows the benefit of both the TeDP system and the flexibility of the developed model. The contribution to knowledge is the evolution of the evaluation model that helps researcher\u27s understand propulsion systems such as the TeDP system of NASA N+3 class aircraft. By identifying and understanding the principal challenges and possibilities provided by the technology, this research further contributes to defining a roadmap of the new technology propulsion system for future research

Implementasi Peraturan Daerah Kota Manado Nomor 20 Tahun 2002 Tentang Penanganan Gelandangan, Pengemis, Tuna Susila Dan Anak Jalanan1

Jenis Penelitian ini adalah bersifat deskriptif kualitatif. Tujuan penelitianadalah untuk mengetahui bagaimana implementasi peraturan daerah kota Manadotentang penangan gelandangan, pengemis, tuna susila dan anak jalanan (studikhusus anak jalanan).Teknik pengumpula data dilakukan dengan beberapa cara yaitu wawancaramendalam arsip/dokumen dari kantor terkait. Adapun informan dalam penelitianini yaitu mewakili Dinas Sosial Kota Manado, LSM/Komunitas/Sanggar yangterkait dengan anak jalanan serta mewakili anak jalanan dan mewakili masyarakat.Teknik analisa data yaitu melalui analisis, komposisi, klasifikasi,dan deskripsimasalah dalam kerangka pembahasan yang telah ditetapkan.Berdasarkan hasil dari penelitian, dapat diketahui bahwa bahwa peraturandaerah nomor 20 tahun 2002 dalam penanganan anak jalanan sudah berjalan baik,namun belum maksimal dalam beberapa hal.Ada beberapa yang ditemukan yangmenyebabkan anak-anak berada di jalanan; ekonomi rendah, kurangnyapemahaman orangtua maupun anak akan gunanya suatu pendidikan, anak-anakmemilih hidup dijalanan yang bebas, dijalanan mereka bisa menghasilkan uangsendiri. Saran bagi pemerintah dapat mendirikan rumah singgah dimanapenanampungan khusus untuk mereka.Rumah singgah disini diharapkan menjadipusat rehabilitasi, dimana anak-anak jalanan diberi suasana dan bekal pelatihanketerampilan, juga pengetahuan tentang norma-norma yang berlaku dalammasyarakat.Pemerintah juga perlu memberikan bantuan sosial serta pemberdayaankeluarga (Perubahan pola pikir dan mental) sehingga hal ini mungkin dapatmencegah anak kembali ke jalanan dan hidup bersama keluarganya

Monopole excitations of baryons in the Nambu - Jona-Lasinio soliton model

We investigate the monopole excitations of the soliton in the Nambu--Jona--Lasinio model. By studying the solutions to the corresponding Bethe--Salpeter equation in the background of the soliton we exclude the existence of real large amplitude fluctuations. This allows us to treat the collective coordinate for the monopole excitations, which parametrizes the extension of the soliton, in the harmonic approximation. The canonical quantization of this coordinate yields a spectrum which agrees reasonably well with the empirical data for the Roper resonance, N(1440), and the corresponding one for the Delta, \Delta(1600). We also comment on going beyond the harmonic approximation

Strange Nucleons and Hyperons as Chiral Solitons in the NJL Model

In the chirally symmetric Nambu--Jona-Lasinio model baryons are described as chiral solitons of mesonic quark--antiquark bound states. Hyperons are investigated in two complementary pictures: the bound state approach of Callan and Klebanov and the collective approach of Yabu and Ando. The latter is used to compute the strange vector form factors of the nucleon providing estimates for the strange electric mean square radius and the strange magnetic moment of the nucleon.Comment: 3 pages, latex, no figures, uses menu95.sty (appended), talk at Sixth International Symposium on ``Meson-Nucleon Physics and the Structure of the Nucleon'', Blaubeuren/Tuebingen, Germany, July 10-14, 1995, to be published in the $\pi N$ Newslette

Strangeness content of the nucleon within the NJL soliton model

We investigated the form factors of the nucleon associated with the nonet vector current in the framework of the generalized Yabu--Ando approach to the chiral soliton of the Nambu--Jona--Lasinio model. We introduce a variational parameter to improve the predictions for the baryon mass splittings and, in addition, we take into account $1/N_c$ rotational corrections to accommodate the empirical isovector magnetic moment of the nucleon. We find that the strange magnetic moment lies between -0.05 and 0.25.Comment: 3 pages, LaTeX file. Talk given at the conference: Hadron 95, July 9th-14th, 1995, Mancheste

Finite-size effects on multibody neutrino exchange

The effect of multibody massless neutrino exchanges between neutrons inside a finite-size neutron star is studied. We use an effective Lagrangian, which incorporates the effect of the neutrons on the neutrinos. Following Schwinger, it is shown that the total interaction energy density is computed by comparing the zero point energy of the neutrino sea with and without the star. It has already been shown that in an infinite-size star the total energy due to neutrino exchange vanishes exactly. The opposite claim that massless neutrino exchange would produce a huge energy is due to an improper summation of an infrared-divergent quantity. The same vanishing of the total energy has been proved exactly in the case of a finite star in a one-dimensional toy model. Here we study the three-dimensional case. We first consider the effect of a sharp star border, assumed to be a plane. We find that there is a non- vanishing of the zero point energy density difference between the inside and the outside due to the refraction index at the border and the consequent non-penetrating waves. An analytical and numerical calculation for the case of a spherical star with a sharp border confirms that the preceding border effect is the dominant one. The total result is shown to be infrared-safe, thus confirming that there is no need to assume a neutrino mass. The ultraviolet cut-offs, which correspond in some sense to the matching of the effective theory with the exact one, are discussed. Finally the energy due to long distance neutrino exchange is of the order of $10^{-8} -- 10^{-13} GeV per neutron$, i.e. negligible with respect to the neutron mass density.Comment: Latex file (Revtex), 34 pages, 8 postscripted figure

Investigation of Selectively-Reinforced Metallic Lugs

An investigation of the effects of material and geometric variables on the response of U-shaped band-reinforced metallic lugs was performed. Variables studied were reinforcement, adhesive and metallic lug mechanical properties, hole diameter, reinforcement and adhesive thickness, and the distance from the hole s center to the end of the lug. Generally, U-shaped band reinforced lugs exhibited superior performance than non-reinforced lugs, that is higher load at the conventional lug design criteria of four percent hole elongation. Depending upon the reinforcement configuration the increase in load may be negligible to 15 or 20 percent. U-shaped band reinforcement increases lug load carrying capability primarily through two mechanisms; increasing the slope of the response curve after the initial knee and restraining overall deformation of the metallic portion of the lug facilitating increased yielding of metallic material between the hole and the edge of the metallic portion of the lug

NRQCD Results on Form Factors

We report results on $f_B$ and semi-leptonic $B$ decay form factors using NRQCD. We investigate $1/M$ scaling behavior of decay amplitudes. For $f_B$ Effect of higher order relativistic correction terms are also studied.Comment: 9 pgs. 10 figures. Latex2e. espcrc2.sty included. Talk presented at the Internatioal Workshop "LATTICE QCD ON PARALLEL COMPUTERS", March 1997, Tsukub