477 research outputs found
Boiler for generating high quality vapor
Boiler supplies vapor for use in turbines by imparting a high angular velocity to the liquid annulus in heated rotating drum. Drum boiler provides a sharp interface between boiling liquid and vapor, thereby, inhibiting the formation of unwanted liquid droplets
Gravitational Collapse of a Homogeneous Scalar Field in Deformed Phase Space
We study the gravitational collapse of a homogeneous scalar field, minimally
coupled to gravity, in the presence of a particular type of dynamical
deformation between the canonical momenta of the scale factor and of the scalar
field. In the absence of such a deformation, a class of solutions can be found
in the literature [R. Goswami and P. S. Joshi, arXiv:gr-qc/0410144],
%\cite{JG04}, whereby a curvature singularity occurs at the collapse end state,
which can be either hidden behind a horizon or be visible to external
observers. However, when the phase-space is deformed, as implemented herein
this paper, we find that the singularity may be either removed or instead,
attained faster. More precisely, for negative values of the deformation
parameter, we identify the emergence of a negative pressure term, which slows
down the collapse so that the singularity is replaced with a bounce. In this
respect, the formation of a dynamical horizon can be avoided depending on the
suitable choice of the boundary surface of the star. Whereas for positive
values, the pressure that originates from the deformation effects assists the
collapse toward the singularity formation. In this case, since the collapse
speed is unbounded, the condition on the horizon formation is always satisfied
and furthermore the dynamical horizon develops earlier than when the
phase-space deformations are absent. These results are obtained by means of a
thoroughly numerical discussion.Comment: 17 pages, 17 figure
Loop quantum effect and the fate of tachyon field collapse
We study the fate of gravitational collapse of a tachyon field matter. In
presence of an inverse square potential a black hole forms. Loop quantum
corrections lead to the avoidance of classical singularities, which is followed
by an outward flux of energy.Comment: Contribution to the conference of Loops'11, Madri
Sequestering atmospheric CO<sub>2</sub> inorganically:a solution for Malaysia's CO<sub>2</sub> emission
Malaysia is anticipating an increase of 68.86% in CO2 emission in 2020, compared with the 2000 baseline, reaching 285.73 million tonnes. A major contributor to Malaysia's CO2 emissions is coal-fired electricity power plants, responsible for 43.4% of the overall emissions. Malaysia's forest soil offers organic sequestration of 15 tonnes of CO2 ha(-1) year(-1). Unlike organic CO2 sequestration in soil, inorganic sequestration of CO2 through mineral carbonation, once formed, is considered as a permanent sink. Inorganic CO2 sequestration in Malaysia has not been extensively studied, and the country's potential for using the technique for atmospheric CO2 removal is undefined. In addition, Malaysia produces a significant amount of solid waste annually and, of that, demolition concrete waste, basalt quarry fine, and fly and bottom ashes are calcium-rich materials suitable for inorganic CO2 sequestration. This project introduces a potential solution for sequestering atmospheric CO2 inorganically for Malaysia. If lands associated to future developments in Malaysia are designed for inorganic CO2 sequestration using demolition concrete waste, basalt quarry fine, and fly and bottom ashes, 597,465 tonnes of CO2 can be captured annually adding a potential annual economic benefit of (sic)4,700,000.</p
MODEL PEMBELAJARAN PROBLEM BASED LEARNING DALAM PENINGKATAN HASIL BELAJAR IPS (STUDI PENELITIAN TINDAKAN KELAS DI SMP NEGERI 2 TOLITOLI)
Penelitian ini bertujuan untuk meningkatkan hasil belajar IPS melalui model problem based learning pada siswa kelas IX SMP Negeri 2 Tolitoli tahun pelajaran 2018/2019. Subjek penelitian Tindakan kelas ini adalah siswa kelas IX SMP Negeri 2 Tolitoli tahun pelajaran 2018/2019 sebanyak 35 siswa sebagai subjek penerima tindakan, sedangkan untuk subjek pelaku tindakan adalah guru IPS kelas IXA selaku guru, teman sejawat selaku subjek yang melakukan observasi proses pembelajaran, Kepala Sekolah selaku subjek sumber data. Metode pengumpulan data dilakukan melalui teknik tes, observasi dan dokumentasi. Penelitian Tindakan ini dilakukan dalam dua siklus, tiap-tiap siklus terdiri dari: perencanaan, tindakan, pengamatan dan refleksi. Hasil penelitian ini menunjukkan bahwa penggunaan model pembelajaran problem based learning dapat meningkatkan hasil belajar IPS siswa kelas IX A SMPN 2 Tolitoli tahun pelajaran 2018/2019. Hal ini dapat dilihat dari nilai rata-rata hasil belajar IPS siswa juga mengalami peningkatan yaitu sebelum Tindakan sebesar 70,88 pada siklus I sebesar 74,80 dan pada siklus II sebesar 85,37. Selain itu, presentase ketuntasan belajar siswa, yaitu sebelum tindakan sebesar 34,28%, pada siklus I sebesar 74,80% dan pada siklus II sebesar 94,28%.Kata Kunci: Problem based learning dan hasil belajar IPS sisw
Thermal properties of Malaysian cohesive soils
The thermal properties of soils surrounding energy piles are required for the efficient and optimal design of shallow geothermal energy pile systems. In this study, the thermal conductivity, thermal resistivity and volumetric specific heat of two types of Malaysian cohesive soil were obtained through a series of laboratory experiments using a thermal needle probe. This study was conducted to determine the effect of moisture content on the thermal conductivity, thermal resistivity and volumetric specific heat values of the cohesive soil at a given value of soil density. For soils with low to medium moisture content, a linear increase in the thermal conductivity and volumetric heat capacity was observed as the moisture content gradually increased, while the thermal resistivity values of the soil had decreased. Meanwhile, for soils with high moisture content, the thermal conductivity was observed to have decreased, and a marked increase was seen in the thermal resistivity. This is due to the disruption of the thermal flow continuity in the soil matrix with the presence of moisture in the soil which adversely affects the thermal conductivity
Multiplierz: An Extensible API Based Desktop Environment for Proteomics Data Analysis
BACKGROUND. Efficient analysis of results from mass spectrometry-based proteomics experiments requires access to disparate data types, including native mass spectrometry files, output from algorithms that assign peptide sequence to MS/MS spectra, and annotation for proteins and pathways from various database sources. Moreover, proteomics technologies and experimental methods are not yet standardized; hence a high degree of flexibility is necessary for efficient support of high- and low-throughput data analytic tasks. Development of a desktop environment that is sufficiently robust for deployment in data analytic pipelines, and simultaneously supports customization for programmers and non-programmers alike, has proven to be a significant challenge. RESULTS. We describe multiplierz, a flexible and open-source desktop environment for comprehensive proteomics data analysis. We use this framework to expose a prototype version of our recently proposed common API (mzAPI) designed for direct access to proprietary mass spectrometry files. In addition to routine data analytic tasks, multiplierz supports generation of information rich, portable spreadsheet-based reports. Moreover, multiplierz is designed around a "zero infrastructure" philosophy, meaning that it can be deployed by end users with little or no system administration support. Finally, access to multiplierz functionality is provided via high-level Python scripts, resulting in a fully extensible data analytic environment for rapid development of custom algorithms and deployment of high-throughput data pipelines. CONCLUSION. Collectively, mzAPI and multiplierz facilitate a wide range of data analysis tasks, spanning technology development to biological annotation, for mass spectrometry-based proteomics research.Dana-Farber Cancer Institute; National Human Genome Research Institute (P50HG004233); National Science Foundation Integrative Graduate Education and Research Traineeship grant (DGE-0654108
Implementasi Metode Kriptografi Advanced Encryption Standard (AES) untuk Proteksi Pesan Audio
This study is to solve the problem Cryptographic techniques used to protect and maintain the confidentiality of audio messages by changing audio messages into audio messages that cannot be played by doing the encryption process and can be played back after the audio message is decrypted. To protect audio messages, it is used in the process of encrypting and decrypting audio messages using the Advanced Encryption Standard (AES) method. The Advanced Encryption Standard (AES) uses symmetric key block passwords with varying key sizes of 128 bits, 192 bits, and 256 bits. The Advanced Encryption Standard (AES) method used is 128 bit key size and there are 10 rounds in the process of encryption and decryption. Audio messages that have been encrypted using the Advanced Encryption Standard (AES) method cannot be played by parties who do not know the key to encrypt and decrypt the audio message. Audio messages are protected and protected from irresponsible parties who want to damage or just listen to the audio message
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