1,999 research outputs found
Study of Coulomb collisions and magneto-ionic propagation effects on incoherent scatter radar measurements at Jicamarca
In this dissertation, Coulomb collisions and magneto-ionic propagation effects on the incoherent scatter radar measurements have been studied and analyzed in detail. The present study aims at modeling radar observations of the equatorial ionosphere carried out at the Jicamarca Radio Observatory (Lima, Peru) using antenna beams pointed perpendicular to the Earth's magnetic field B.
A Monte Carlo procedure based on the simulation of charged particle trajectories in a magnetized plasma (with suppressed collective interactions) was developed to account for the effects of Coulomb collisions on the shape of the incoherent scatter spectrum. Statistics of simulated electron and ion trajectories, single-particle ACF's, and associated Gordeyev integrals are utilized in the general framework of incoherent scatter spectrum models (e.g., Kudeki and Milla, 2006) to produce theoretical spectra for different plasma configurations. Our simulation method effectively extends the procedure of Sulzer and Gonz??lez (1999) into three dimensions and is valid for all magnetic aspect angles including the direction perpendicular to B. The 3D trajectories, randomized by Coulomb collisions, are described by a generalized Langevin equation with velocity-dependent friction and diffusion coefficients taken from the standard Fokker-Planck collision model of Rosenbluth et al. (1957). A statistical analysis of the simulated trajectories shows that the ion motion is well modeled as a Brownian-motion process with Gaussian displacement distributions (and constant friction and diffusion coefficients), in which case, an analytical expression for the single-ion ACF can be obtained (e.g., Woodman, 1967). However, the simulated electron motions do not fit a Brownian model because the electron displacement distributions in the direction parallel to B are sharper than a Gaussian. To account for these effects on our incoherent scatter spectrum model, a numerical library of electron statistics in an oxygen plasma (single-electron ACF's) had to be developed. The library spans a set of densities, temperatures, and magnetic fields as needed for Jicamarca F-region applications.
The antenna beams used in perpendicular-to-B radar observations at Jicamarca have angular widths of the order of a degree. Within this range of small magnetic aspect angles, different modes of magneto-ionic wave propagation are excited. These characteristic modes vary from linearly polarized in the direction perpendicular to B (Cotton-Mouton regime) to circularly polarized at aspect angles greater than 0.5 deg (Faraday rotation regime). In order to model the magneto-ionic propagation effects on incoherent scatter radar measurements, a computer algorithm based on the Appleton-Hartree equation for electromagnetic wave propagation in a magnetized plasma was developed. Simulation studies show that magneto-ionic propagation effectively modifies the shapes of the radar beams and does have an impact on the incoherent scatter radar measurements because the polarization of the incident and backscattered fields vary as they propagate through the ionosphere.
A soft-target radar equation, which incorporates our collisional incoherent scatter spectrum and magneto-ionic propagation models, is formulated to model the radar measurements collected at Jicamarca. Voltages detected by the radar antenna are represented as the beam-weighted sum of ionospheric backscattered signals corresponding to the range of magnetic aspect angle directions illuminated by the antenna beam. This integration is carried out numerically using a finite-element-like integration method that takes advantage of the slow variation of physical parameters in the direction transverse to the geomagnetic field. The resultant radar model is utilized in the inversion of ionospheric parameters in a three-beam radar experiment conducted at Jicamarca. The experiment interleaves radar observations with perpendicular-to-B and off-perpendicular antenna beams. The data model matches very closely the different features of the measured data; for instance, it predicts the enhancement of the measured power in the direction perpendicular-to-B at ionospheric altitudes where the electron temperature is greater than the ion temperature. F-region electron density and temperature ratio (T_e/T_i) estimates were obtained using a least-squares inversion algorithm. The inversion results show a good agreement with ionosonde data, validating our model for incoherent scatter radar measurements
Potensi Pemanfaatan Ekosistem Pesisir Pantai Labuhan Haji Lombok Timur sebagai Daerah Ekowisata
Penelitian ini bertujuan untuk menganalisis potensi-potensi yang dimiliki oleh ekosistem pesisir pantai Labuhan Haji Lombok Timur untuk dikembangkan menjadi daerah ekowisata. Metode penelitian yang digunakan adalah analisis deskriptif melalui kegiatan kajian pustaka/ literature yang dilakukan untuk mendapatkan informasi terkait dengan judul penelitian. Hasil analisis menunjukkan bahwa ekosistem pesisir pantai Labuhan Haji memiliki potensi yang besar dalam memberikan jasa/ layanan ekosistem khususnya jasa kebudayaan dari ekosistem tersebut. Potensi yang dimiliki diantaranya memiliki bentang alam indah yang banyak dimanfaatkan oleh wisatawan yang ingin melihat keindahan matahari saat terbit, pantai dengan ombak yang tidak terlalu tinggi, dikelilingi oleh persawahan dan perkebunan masyarakat yang masih alami. Banyaknya potensi yang dimiliki oleh ekosistem pesisir Pantai Labuhan Haji yang didukung oleh peran serta masyarakat sebagai pengelola dan wisawatan untuk memelihara dan menjaga ekosistem tersebut dari kerusakan ataupun terhadap pencemaran lingkungan mennyebabkan ekosistem pesisir pantai Labuhan Haji tepat jika dikembangkan sebagai salah satu daerah ekowisata yang ada di Lombok Timur. Kata Kunci: Ekosistem pesisir, Jasa kebudayaan Ekosistem, Ekowisata. Abstact This study aims to analyze the potentials possessed by the coastal ecosystem of Labuhan Haji Lombok Timur to be developed into ecotourism area. The research method used is descriptive analysis through literature review activities / literature conducted to obtain information related to the title of research. The results of the analysis indicate that the coastal ecosystem of Labuhan Haji has great potential in providing ecosystem services / services, especially the cultural services of the ecosystem. Potentials of which have beautiful landscapes are widely used by tourists who want to see the beauty of the sun when rising, the beach with a wave that is not too high, surrounded by rice fields and plantations that are still natural communities. The number of potency possessed by coastal ecosystem of Labuhan Haji Beach which supported by society participation as manager and wisawatan to maintain and maintain the ecosystem from damage or to environmental pollution mennyebabkan coastal ecosystem Labuhan Haji precisely if developed as one of ecotourism area in Lombok East
Analisis Partisipasi Masyarakat dalam Pembangunan Sumber Daya Manusia di Desa Gadingkulon, Kecamatan DAU, Kabupaten Malang
: People participation analysis in human resource development in Gadingkulon village is an important thing in order to improve human resource skills by involving people participation actively in each development process.The research use qualitative approach with data collection technique via interview, observation, and documentation, while informer in this research is village government and society by taking samples using snowball sampling. To test data validity, researcher uses technique triangulation. Data analysis is done by data reduction, data serve, and conclusion taking. Research result are: 1) people participation in human resource development in Gadingkulon village, whether in human resource development planning or human resource development application is huge, but in supervising level, it needs optimization; 2) method in improving people participation in developing human resource through education or health are: cooperating with outside party, whether government or private institution to facilitate people in giving training and education, also educated people participation to actualize each skill and knowledge possessed.
Keywords: Participation, Development, Human Resourc
Herrerillo común – Cyanistes caeruleus (Linnaeus, 1758)
Aves - Orden Passeriformes - Familia Paridae en la Enciclopedia Virtual de Vertebrados Españoles, http://www.vertebradosibericos.org/. Versiones anteriores: 30-06-2005; 9-03-2007; 12-03-2008; 28-09-2012A comprehensive review of the natural history of the Blue tit Cyanistes caeruleus in Spain.Peer reviewe
Evaluasi Program GEMERLAP di Desa Candisari Kecamatan Sambeng: Studi Deskriptif pada Kelompok Tani Holtikultura “Godong Ijo Sejahtera” ( Evaluation of GEMERLAP Program in Candisari Village, Sambeng Subdistrict: Descriptive Study of Horticultural Farmers '
AbstractThis research aims to evaluate the program of the Movement to Build a Village Based Society Economy inCandisari village, Sambengsub district. This descriptive research employed a qualitative approach. Theinformants were determined purposively. Research data were collected through observation, interview, anddocumentation. Data were analyzed by using interactive analysis of Miles and Huberman which consistedof data reduction, data presentatio n, and drawing conclusion. To test data validity, researchers used sourcetriangulation. The theory used in evaluating the Movement to Build a Village Based Society Economy wasWilliam N Dunn's evaluation theory. Based on the findings, from the six William N Dunn criteria used toevaluate, only two were fulfilled namely leveling and accuracy. While the other four criteria, namelyeffectiveness, efficiency, adequacy, and responsiveness were still poor. This condition was due to severalfactors, namely the la ck of optimal effort of government in implementing the program and overcoming theepidemics. This condition happened because the Calina Papaya program was not included in the RoadMap of the Office of Food Crops, Plantation, and Horticulture.Keywords:pro gram evaluation , GEMERLA
Renormalized coordinate approach to the thermalization process
We consider a particle in the harmonic approximation coupled linearly to an
environment. modeled by an infinite set of harmonic oscillators. The system
(particle--environment) is considered in a cavity at thermal equilibrium. We
employ the recently introduced notion of renormalized coordinates to
investigate the time evolution of the particle occupation number. For
comparison we first present this study in bare coordinates. For a long ellapsed
time, in both approaches, the occupation number of the particle becomes
independent of its initial value. The value of ocupation number of the particle
is the physically expected one at the given temperature. So we have a Markovian
process, describing the particle thermalization with the environment. With
renormalized coordinates no renormalization procedure is required, leading
directly to a finite result.Comment: 16 pages, LATEX, 2 figure
GIS, GPS, and Remote Sensing Technologies in Extension Services: Where to Start, What to Know
The rapid development and integration of spatial technologies such as Geographic Information Systems, the Global Positioning System, and remote sensing, have created many new tools for Extension professionals, but have also widened the digital divide, leaving many with little understanding of the technology and potential applications. This article presents examples of Extension-related applications of GIS-GPS-RS technologies and discusses how to go about learning more and determining if these technologies would be useful. Examples and recommendations are taken from the literature and from the authors\u27 own experience
The feasibility of wireless capsule endoscopy in detecting small intestinal pathology in children under the age of 8 years: a multicentre European study.
Objective: To systematically evaluate the feasibility and methodology to carry out wireless capsule endoscopy (WCE) in children <8 years to define small intestinal pathology.
Design: Prospective European multicentre study with negative prior investigation.
Patients and interventions: 83 children aged 1.5–7.9 years were recruited. Initially, all were offered “swallowing” (Group 1) for capsule introduction. If this failed endoscopic placement (Group 2) was used and the Roth net, Advance or custom-made introducers were compared.
Outcome measures: Primary endpoint: to determine pathology; secondary endpoint: comparison of capsule introduction methods.
Results: Capsule introduction: 20 (24%) children aged 4.0–7.9 years (mean, 6.9 years; 14 male) comprising Group 1 were older (p<0.025) than 63 (76%) aged 1.5–7.9 years (mean, 5.25 years; 30 male) forming Group 2. Complications: Roth net mucosal trauma in 50%; no others occurred. The available recording apparatus was inappropriate for those <3 years. Indications: gastrointestinal bleeding: n = 30 (16 positive findings: four ulcerative jejunitis, four polyps, two angiodysplasia, two blue rubber blebs, two Meckel’s diverticula, one anastomotic ulcer, one reduplication); suspected Crohn’s disease: n = 20 (11 had Crohn’s disease); abdominal pain: n = 12 (six positive findings: three Crohn’s disease, two lymphonodular hyperplasia, one blue rubber bleb); protein loss: n = 9 (four lymphangectasia); malabsorption: n = 12 (seven positive findings: six enteropathy, one ascaris). No abnormalities overall: 45%.
Conclusion: WCE is feasible and safe down to the age of 1.5 years. 20 children >4 years swallowed the capsule. The Advance introducer proved superior for endoscopic placement. The pathologies encountered showed age specificity and, unlike in adolescents, obscure gastrointestinal bleeding was the commonest indication
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