3,536 research outputs found
The Observable Thermal and Kinetic Sunyaev-Zel'dovich Effect in Merging Galaxy Clusters
The advent of high-resolution imaging of galaxy clusters using the
Sunyaev-Zel'dovich Effect (SZE) provides a unique probe of the astrophysics of
the intracluster medium (ICM) out to high redshifts. To investigate the effects
of cluster mergers on resolved SZE images, we present a high-resolution
cosmological simulation of a 1.5E15 M_sun adiabatic cluster using the TreeSPH
code ChaNGa. This massive cluster undergoes a 10:3:1 ratio triple merger
accompanied by a dramatic rise in its integrated Compton-Y, peaking at z =
0.05. By modeling the thermal SZE (tSZ) and kinetic SZE (kSZ) spectral
distortions of the Cosmic Microwave Background (CMB) at this redshift with
relativistic corrections, we produce various mock images of the cluster at
frequencies and resolutions achievable with current high-resolution SZE
instruments. The two gravitationally-bound merging subclusters account for 10%
and 1% of the main cluster's integrated Compton-Y, and have extended merger
shock features in the background ICM visible in our mock images. We show that
along certain projections and at specific frequencies, the kSZ CMB intensity
distortion can dominate over the tSZ due to the large line of sight velocities
of the subcluster gas and the unique frequency-dependence of these effects. We
estimate that a one-velocity assumption in estimation of line of sight
velocities of the merging subclusters from the kSZ induces a bias of ~10%. This
velocity bias is small relative to other sources of uncertainty in
observations, partially due to helpful bulk motions in the background ICM
induced by the merger. Our results show that high-resolution SZE observations,
which have recently detected strong kSZ signals in subclusters of merging
systems, can robustly probe the dynamical as well as the thermal state of the
ICM.Comment: MNRAS, accepted. 13 pages, 9 figure
Characterization of Legacy Sediment variations in accretion and carbon dynamics following dam removal in a recently restored tidal freshwater wetland
Damming disrupts the natural flow of sediment to adjoining water bodies resulting in the accumulation of Legacy Sediments (LS). While the impact of LS inputs has been well investigated in lotic Mid-Atlantic piedmont stream restorations, (i.e. milldam removal 1,2,3,4,5,), there have been few studies investigating LS following dam removal in low-gradient coastal plain streams. The objectives of this study were to quantify spatial and temporal variations of LS characteristics in a low-gradient tidal stream restoration within the lower James River watershed. Secondary objectives were to assess the current temporal and spatial variability in sediment deposition within the recently restored Kimages Creek wetlands and adjacent, unaltered wetlands of Harris Creek to investigate current sedimentation processes in a restoration setting
PENGARUH PERBANDINGAN VOLUME FLUIDA KERJA PADA EVAPORATOR TERHADAP KINERJA THERMAL AXIAL GROOVE HEAT PIPE
Heat pipe adalah sebuah tabung tertutup yang didalamnya terdapat fluida kerja, terdiri dari tiga bagian yaitu evaporator, adiabatic dan kondensor. Ketika beroperasi fluida kerja pada sisi evaporator tervaporasi dengan menyerap panas lingkungan dan kembali terkondensasi dengan melepas panas pada sisi kondensor. Penelitian ini bertujuan untuk menyelidiki pengaruh perbandingan volume fluida kerja (working fluid)dengan volume evaporator terhadap kinerja thermal axial groove heat pipe.
Heat pipe dibuat dari tembaga dengan diameter 12,7 mm dan panjang 500 mm. Daerah evaporator sebagai sisi yang dikenai sumber panas, bagian adiabatis diisolasi sehingga tidak ada pertukaran panas dengan lingkungan dan daerah kondensor dipasang heat sink yang bertujuan untuk membuang panas dari heat pipe ke lingkungan. Variasi Volume working fluida yang digunakan dalam penelitian ini adalah prosentase dari volume bagian evaporator, yaitu 10%, 25%, 40%, 55%,70%, 85% dan 100%. Data yang diperlukan adalah temperatur pada evaporator (Te), temperature bagian kondensor (Tk1, Tk2,Tk3) dan temperature udara (Tu).
Hasil penelitian menunjukkan bahwa,semakin besar perbandingan volume fluida dengan volume evaporator (100%)untuk semua temperatur, maka akan semakin kecil tahanan thermalnya. Pada semua volume fluida, pada temperatur terendah mempunya tahanan thermal tertinggi dan semakin mengecil nilainya sampai pada saat temperatur terbesar. Kapasitas terbesar dan daya output terbesar adalah pada saat temperatur terbesar
The phase-space density distribution of dark matter halos
High resolution N-body simulations have all but converged on a common
empirical form for the shape of the density profiles of halos, but the full
understanding of the underlying physics of halo formation has eluded them so
far. We investigate the formation and structure of dark matter halos using
analytical and semi-analytical techniques. Our halos are formed via an extended
secondary infall model (ESIM); they contain secondary perturbations and hence
random tangential and radial motions which affect the halo's evolution at it
undergoes shell-crossing and virialization. Even though the density profiles of
NFW and ESIM halos are different their phase-space density distributions are
the same: \rho/\sigma^3 ~ r^{-\alpha}, with \alpha=1.875 over ~3 decades in
radius. We use two approaches to try to explain this ``universal'' slope: (1)
The Jeans equation analysis yields many insights, however, does not answer why
\alpha=1.875. (2) The secondary infall model of the 1960's and 1970's,
augmented by ``thermal motions'' of particles does predict that halos should
have \alpha=1.875. However, this relies on assumptions of spherical symmetry
and slow accretion. While for ESIM halos these assumptions are justified, they
most certainly break down for simulated halos which forms hierarchically. We
speculate that our argument may apply to an ``on-average'' formation scenario
of halos within merger-driven numerical simulations, and thereby explain why
\alpha=1.875 for NFW halos. Thus, \rho/\sigma^3 ~ r^{-1.875} may be a generic
feature of violent relaxation.Comment: 4 pages, 1 fig. Proceedings of Science (SISSA), "Baryons in Dark
Matter Haloes", Novigrad, Croatia, 5-9 October 2004; editors: R.-J. Dettmar,
U. Klein, P. Salucci. The full paper is astro-ph/0506571 (with minus sign in
eq.(2.2) corrected
DIE ANWENDUNG VON DER PREP TECHNIQUE METHODE FÜR DEUTSCH LESEFERTIGKEITEN THEMA ALLTAGSLEBEN IN DER KLASSE XI IPA 2 SMAN 12 SURABAYA
PReP Technique is applied as an alternative method of Reading comprehension to German language. This Method allows students whom can understand the passage clearly and gain the main of a passage. PReP Technique helps students more active and improve cognitive students to present information from Reading Text. The Research is conducted in SMA Negeri 12 Surabaya. The Background of Research is importance of Mental Activation Processes in the Cognitive system, and memory optimization of students in order to show their own abilities. The purpose of this research is to apply the PReP Technique on Reading comprehension in XI IPA 2 SMA Negeri 12 Surabaya in Alltagsleben theme. In this Research, the issues forming the subject matter is: How the PReP Technique can be applied for Germany language reading comprehension for the student of SMA Negeri 12 Surabaya class XI – IPA 2 thema Alltagsleben? the data is the observation of teachers and a students during the PReP Technique method application for Reading comprehension of German language text. The results shows that the process of learning for reading is done using PReP Technique well performing. This is substantiation by the implementation of measures contained in the PReP Technique method application for 5 times the initial Association process, Reflections, Reformation of Knowledge, and Evaluation. By looking at the result of the observation of teachers, enthusiastic student, as well as the results of training given to the students is good enough during the PReP Technique method application. So in this case we will know that the implementation the PReP Technique method application give a positive effect on student’s readiness before reading.
Keywords : Pre Reading Plan (PReP) Technique, Reading, German language tex
BAGIAN WARISAN BAGI ANAK ANGKAT MENURUT KETENTUAN HUKUM ISLAM DAN HUKUM POSITIF DI INDONESIA
Salah satu tujuan utama dari perkawinan adalah untuk menyambung keturunan. Akan tetapi tidak semua pasangan suami isteri dapat memiliki anak. Ketidakberadaan anak dapat menjadi salah satu pemicu ketidakharmonisan hubungan rumah tangga. Sehingga untuk mempertahankan keutuhannya, suami isteri melakukan pengangkatan anak. Dalam pengangkatan anak tentu akan menimbulkan akibat hukum. Terlebih lagi di dalam hukum di Indonesia, pengangkatan anak dilakukan menurut hukum Islam, hukum Adat (hukum Adat yang dimaksud adalah hukum Adat Jawa Tengah), dan hukum Perdata. Dimana ketiga sistem hukum tersebut tentu saja akan menimbulkan akibat hukum yang berbeda-beda. Akibat hukum tersebut berkaitan dengan status dan kedudukan anak angkat yang meliputi hubungan keluarga, hubungan perwalian, hubungan waris, serta hubungan-hubungan lainnya. Mengenai hubungan waris, di Indonesia masih bersifat pluralisme diantaranya hukum waris Islam, hukum waris Adat dan hukum waris dalam Kitab Undang-Undang Hukum Perdata. Sehingga dengan beragamnya hukum waris yang berlaku tersebut, turut menyebabkan perbedaan terhadap bagian waris yang diperoleh anak angkat
Sengketa Perbatasan Wilayah Kashmir dalam Perspektif Hukum Internasional
Riadhi Alhayyan 090200029 Kashmir border dispute was very influential and disturbing in the South Asia region, because the dispute involves two major states of India and Pakistan. The bickering two countries fighting over kashmir region as the territory continues and has attracted a lot of attention from various countries in the settlement of the dispute. Kashmir border dispute has put a serious challenge for analysts and policy makers because the conflict is complex and heterogeneous. Kashmir, the disputed territory that lies at the foot of the Himalayas, under the rule of the three countries. Jammu-Cash Society ¬ hmir entered Indian territory, while the people of Ladakh and Jammu-Kashmir-Pakistan respectively controlled by China and Pakistan. Among the three, only the Jammu-Kashmir's turbulent and demanding independence. The research method with normative legal research or legal research literature conducted by examining the literature material, and empirical legal research. The study used the law is normative legal research or collectively, the literature study (library research) with the acquisition of secondary data sourced cider magazines, books, journals, newspapers, online websites, and other library documents. Analysis of the data used is qualitative analysis, ie data obtained and subsequently systematically compiled and then analyzed qualitatively in order to achieve clarity issues to be discussed and the results are set forth in the form of a thesis. Based on the results of the study authors that the status area Kashmir under International law is in dispute, as India and Pakistan both claim Kashmir as their territory. But the ruler of Kashmir when it was a Hindu, would prefer to join with India, so that Kashmiris are now split into two, Pakistan and Kashmir Kashmir India. Kashmir struggle in a dilemma. If using peaceful means and approach to politics, India claimed that the people of Kashmir have accepted the status quo, to be a part of India. Kashmir territorial dispute and the Kashmir conflict occurs because of a conflict of interest between the two countries and the political power that is manifested through unilateral claims of India and Pakistan. Including religious factor, Pakistan claims that the khasmir is a muslim majority area integral for Pakistan while also claiming in kashmir hindu community are integrated with India. Factors as well as border, it is located in the teritory of Kashmir Indian authorities, however, a dispute can not be separated from the colonial regime that tends to make the inter-state border artificially, meanings the colonial regime tends to create a new border regime without notice in the interests of natural factors such as ethnicity,and socio-cultural condition. Solution to solve the Kashmir region between India struggle with Pakistan should be implemented bilateral relations between the two countries. UN and SAARCsebaiknya entitles India and Pakistan over the Kashmir region in accordance with the location of each region. So there is no reason for India and Pakistan to fight each other for control of the Kashmir region as a whole. In addition, the United Nations and the SAARC should be decisive in resolving the Kashmir conflict annexation. For countries that do not abide by the decision of the United Nations and the SAARC should be subject to strict law.
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