29,882 research outputs found
Linking Light Scalar Modes with A Small Positive Cosmological Constant in String Theory
Based on the studies in Type IIB string theory phenomenology, we conjecture
that a good fraction of the meta-stable de Sitter vacua in the cosmic stringy
landscape tend to have a very small cosmological constant when
compared to either the string scale or the Planck scale , i.e.,
. These low lying de Sitter vacua tend to be
accompanied by very light scalar bosons/axions. Here we illustrate this
phenomenon with the bosonic mass spectra in a set of Type IIB string theory
flux compactification models. We conjecture that small with light
bosons is generic among de Sitter solutions in string theory; that is, the
smallness of and the existence of very light bosons (may be even the
Higgs boson) are results of the statistical preference for such vacua in the
landscape. We also discuss a scalar field model to illustrate
how this statistical preference for a small remains when quantum loop
corrections are included, thus bypassing the radiative instability problem.Comment: 35 pages, 7 figures; added subsection: Finite Temperature and Phase
Transitio
An investigation of combustion instability in aircraft-engine reheat systems
The principal objective of this study was to examine experimentally
the effects of upstream temperature, velocity, gutter blockage, tailpipe
length, and main and pilot fuel flows, on the form of combustion instability
encountered in aircraft reheat systems which is sometimes referred to as 'buzz'.
Tests were carried out at atmospheric pressure for upstream temperatures of
between 200 and 500°C, and upstream velocities ranging from 140 to 200 ft/sec.
Three values of stabilizer blockage were employed, namely 25, 30 and 35%.
The tailpipe length was varied between 9 and 45 inches. Auto-correlation
techniques were used in the frequency analysis of the buzz waveforms.
It was found that a certain minimum tailpipe length is necessary in
order to produce buzz which is then strengthened as the tailpipe length is
increased. Buzz also becomes more pronounced with an increase in gas velocity
but stabilizer blockage appears to have no discernible effect … [cont.]
Effects of harvesting methods on sustainability of a bay scallop fishery: dredging uproots seagrass and displaces recruits
Fishing is widely recognized to have profound effects on estuarine and marine ecosystems (Hammer and Jansson, 1993; Dayton et al., 1995). Intense commercial and recreational
harvest of valuable species can result in population collapses of target and nontarget species (Botsford et al.,
1997; Pauly et al., 1998; Collie et al. 2000; Jackson et al., 2001). Fishing gear, such as trawls and dredges, that
are dragged over the seafloor inflict damage to the benthic habitat (Dayton et al., 1995; Engel and Kvitek, 1995;
Jennings and Kaiser, 1998; Watling and Norse, 1998). As the growing human population, over-capitalization, and increasing government subsidies of fishing place increasing pressures on marine resources (Myers, 1997), a clear understanding of the mechanisms by which fishing affects coastal systems is required to craft sustainable fisheries management
Analisis Yuridis Penegakan Pasal 351 Kuhp pada Perkelahian Antar Pemain dalam Pertandingan Sepak Bola
Skripsi ini membahas tentang analisa yuridis normatif terhadap perkelahian antar pemain dalam sepak bola. Sepak bola merupakan olahraga masyarakat sedunia yang menggunakan full body contact yang terkadang menjurus ke arah kasar dan keras. Peraturan Manual Liga dibuat sebagai upaya menjaga sportifitas dalam bertanding dan menjaga pemain dari unsur permainan yang keras menjurus kasar. Terkait dengan hal tersebut, permasalahan yang diangkat dalam skripsi ini adalah pakah perkelahian antar pemain dalam suatu pertandingan sepak bola dapat dipidana berdasarkan Pasal 351 KUHP tentang tindak pidana penganiayaan. Tujuan dari pembuatan skripsi ini adalah Untuk mengetahui dan menganalisis apakah perkelahian antar pemain dalam suatu pertandingan sepak bola dapat dipidana berdasarkan Pasal 351 KUHP tentang tindak pidana penganiayaan. Metode pendekatan yang digunakan adalah yuridis normatif kemidian dilakukan analsis secara preskriptif kualitatif.Berdasarkan hasil analsis sumber hukum dapat ditarik kesimpulan bahwa perkelahian antar pemain sepak bola tidak dapat dipidana berdasarkan pasal 351 KUHP karena berdasarkan The Laws of The Game FIFA sepanjang jalannya pertandingan sepak bola 2 x 45 menit itu merupakan kewenangan PSSI. Dan yang berhak memberi sanksi jika ada perkelahian antar pemain dalam pertandingan sepak bola tesebut adalah wasit, berupa kartu kuning dan merah. Selain wasit yang berhak memberi hukuman adalah komisi disiplin PSSI.Menyikapi fakta-fakta tersebut diatas diharap pihak kepolisian tidak mencampuri wilayah hukum PSSI pada saat pertandaingan dalam kurun waktu 2x45 menit karena sesuai dengan peraturan FIFA yang menyebutkan bahwa 2x45 menit di lapangan merupakan wewenang daripada wasit sebagai pengadil di dalam pertandingan tersebut.Kata kunci : Sepakbola, Persatuan Sepakbola Seluruh Indonesia (PSSI), Penganiayaa
Orientation filtering by growth-velocity competition in zone-melting recrystallization of silicon on SiO_2
We describe a method of controlling the in-plane directions of grains in (100)-textured silicon films produced by zone-melting recrystallization over amorphous SiO2. Grains having in-plane orientation within a narrow range are able to grow through an orientation filter consisting of a pattern of crystallization barriers, while grains having other orientations are occluded. The results of experiments using an orientation filter, and the parameters which optimize filter performance, are reported
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