495 research outputs found
DC SQUID based on the mesoscopic multiterminal Josephson junction
A theory is offered for a novel device, mesoscopic four-terminal SQUID. The
studied system consists of a mesoscopic four-terminal junction, one pair of
terminals of which is incorporated in a superconducting ring and the other one
is connected with a transport circuit. The nonlocal weak coupling between the
terminals leads to effects of phase dragging and magnetic flux transfer. The
behaviour of a four-terminal SQUID, controlled by the external parameters, the
applied magnetic flux and the transport current is investigated. The critical
current and the current voltage characteristics as functions of magnetic flux
are calculated. In the nonlocal mesoscopic case they depend not only on the
magnitude of the applied flux but also on its sign, allowing measurement of the
direction of the external magnetic field.Comment: 11 pages, 4 figures, presented at the EUCAS 2001 conferenc
Multi-Terminal Superconducting Phase Qubit
Mesoscopic multi-terminal Josephson junctions are novel devices that provide
weak coupling between several bulk superconductors through a common normal
layer. Because of the nonlocal coupling of the superconducting banks, a current
flow between two of the terminals can induce a phase difference and/or current
flow in the other terminals. This "phase dragging" effect is used in designing
a new type of superconducting phase qubit, the basic element of a quantum
computer. Time-reversal symmetry breaking can be achieved by inserting a
pi-phase shifter into the flux loop. Logical operations are done by applying
currents. This removes the necessity for local external magnetic fields to
achieve bistability or controllable operations.Comment: 7 pages, 3 figure
SEGMENTASI CITRA BATIK BERDASARKAN FITUR TEKSTUR MENGGUNAKAN METODE FILTER GABOR DAN K-MEANS CLUSTERING
Batik Pekalongan adalah salah satu kekayaan intelektual dan kebudayaan yang dimiliki oleh Indonesia yang harus dilestarikan dan dilindungi agar tidak diakui oleh bangsa lain. Salah satu cara untuk melestarikan dan melindungi batik Pekalongan adalah dengan melakukan pendataan secara komputerisasi yang berupa pengenalan pola. Dalam pengenalan pola, segmentasi citra merupakan proses yang pertama kali dilakukan sebelum proses selanjutnya yaitu analisis citra. Fungsi utama dari segmentasi citra adalah membagi citra ke dalam bagian-bagian wilayah (sub-regions) yang mempunyai kesamaan fitur antara lain: tekstur, warna, bentuk dan lain sebagainya. Tujuan dari penelitian ini adalah menganalisis hasil segmentasi menggunakan metode Filter Gabor dan K-means Clustering yang digunakan untuk membantu proses awal identifikasi batik Pekalongan berdasarkan fitur tekstur. Pada penelitian ini akan dilakukan pengumpulan data sesuai dengan topik yang diambil melalui observasi, wawancara, dan studi pustaka. Analisis dilakukan untuk menentukan kebutuhan yang berkaitan dengan fungsionalitas dan fasilitas aplikasi yang akan dirancang. Implementasi sistem pada proses segmentasi citra batik Pekalongan yaitu menggunakan Matlab 7.10. Sistem yang dihasilkan kemudian dilakukan pengujian dengan memproses 4 sampel citra dimana 1 sampel diambil 1 jenis citra. Citra akan diproses dan akan dibandingkan berdasarkan kombinasi dari nilai gamma, theta, dan lambda. Pengujian dilakukan dengan menggunakan 4 sampel motif Pekalongan dimana 1 sampel hanya diambil 1 jenis citra dan masing-masing jenis citra akan diuji sebanyak 18 kali. Hasil penelitian yang telah dilakukan dapat disimpulkan bahwa hasil segmentasi citra terbaik berada saat nilai gamma= 0.5, theta= 90, dan lambda= 15 sedangkan jika menggunakan nilai gamma, theta, dan lambda selain itu akan menghasilkan kualitas yang kurang baik. Sehingga hasil segmentasi yang dihasilkan dapat digunakan untuk proses analisis citra
KONTRIBUSI USAHA BUDIDAYA RUMPUT LAUT (Eucheuma cottonii) TERHADAP PENDAPATAN KELUARGA (Studi Kasus Desa Arungkeke, Kecamatan Arungkeke, Kabupaten Jeneponto)
This research aims to find out the amount of income which is earned by seaweed farmers (Eucheuma cottonii) and to figure out the amount of income resulted from seaweed farming business towards the total of family???s income in arungkeke village, arungkeke district, Jeneponto regency. The benefits of this research is to show how far the contribution of seaweed business is at arungkeke village, arungkeke district, Jeneponto regency as information materials and consideration for the government in decision making and potential areas, and also as reference for other students who are interested for the next research. \ud
This research was held from April to May 2011 in arungkeke village, arungkeke district, Jeneponto regency. The location is chosen intentionally (purposive) by considering those locations are development areas of seaweed farming (Eucheuma cottonii), the largest producers in south Sulawesi. Method of research is survey method; a research takes place directly in the field by taking samples of representative population and using questioner as the source of data. Technique of collecting sample in this research is sample random sampling (taking sample randomly). The sample is taken randomly so that each unit of the population has equal chance to be researched. The number of farmers who run seaweed business in arungkeke village is 153 people. Therefore, the number of samples taken in this research is 22 people. \ud
The result of this research shows that the income from seaweed farming business (Eucheuma cottonii) is Rp. 29.590.121 per year; family???s income (total income) is Rp. 45.135.619 per year. So, the contribution of seaweed farming business (Eucheuma cottonii) towards family???s income (total income) is around 65.51
Factors Affecting Incidence of Uterine Torsion in Egyptian Buffaloes (Bubalus bubalis) and its Response for Rolling
Objective: The present work was planned to study the incidence of uterine torsion in Egyptian buffaloes as well as its prognosis after mechanical treatment.Methods: A total number of 35 buffaloes of different ages, parities and stage of pregnancy with complain of colic and anorexia were included in the present study. These animals were examined rectally to detect stage of pregnancy, degree, direction, duration, location of uterine torsion. Mechanical handling of torsion cases and prognosis of recovered cases was performed. After birth, sex of new born was also recorded.Results: The torsion of uterus mostly occurred in pleuriparous buffaloes (100%) in right side (85.7%) during second half of pregnancy (100%). Most cases were postcervical (85.7%) during the early stage (7 and 8 months). Torsion also may occur during labour (17.4%) where the cervix was dilated after correction. Most cases of uterine torsion occur in stabled animals for long period (97%). The uterine torsion associated with male calves (65.7%) as well as with large size calves (40-50kg) and majority of the calves were in normal position. The first foetal sac expelled in majority of cases was amniotic sac (97%) with few cases of placental retention. Uterine torsion with short duration (1-6 h) usually needs 1-2 rolls only for correction and usually takes 0-6h (100%) for cervical dilatation. Occurrence of uterine torsion for above three days usually did not respond for rolling.Conclusion: Uterine torsion usually occurs in old stabled animal with good BCS during green season at last month of pregnancy. The right sever and post cervical torsion were the most common type of torsion. Rapid diagnosis of uterine torsion within 6 h usually results in good prognosis even in severe cases
Examining the Incidence, Depth and Severity of Food Insecurity among rural Households in Nigeria
A nationally representative sample of 3380 rural households from General Household Survey-panel data that adopt the World Bank Living Standard Measurement Survey (LSMS) technique was used for this study. Based on 2120 kcal Food and Agricultural Organization (FAO) recommended per adult equivalent and USD 0.87 purchasing power parity (PPP), an annual food poverty threshold of (N50, 331.67) equivalent to USD 317.55 per annum was derived for Nigeria. This threshold is the cost for purchasing recommended daily food allowances (RDA) of an adult equivalent for healthy life in rural Nigeria estimated at N138. Despite the fact that agricultural sector employed over 70% of the country’s population overwhelmingly large segment of Nigerians especially farming families in rural areas are the most food insecure. The food security situation in Nigeria was examined using the Foster Greer and Thorbecke (FGT) class of decomposable food poverty measures that satisfy both monotonicity and transfer axioms. The food insecurity indices at national level was reported as (?=0, 46.36, ?=1, 0.43 and ?=2, 1.11 for and ?=0, 42.78, ?=1, 0.348 and ?=2, 7.45) for post-harvest seasons respectively. This implies that almost half of the rural households in Nigeria are food insecure subsisting on less the RDAs, however, depth and severity of food insecurity also differ. Disaggregating the households based geo-political zones and some key socio-economic characteristics, further indicates a significant differences based on the relative size of the coefficient of ?. We conjecture that, the higher incidence of food security during post harvesting season might likely be due to inability of smallholder farmers to utilize their time into non-farm income generating activities due to high demand for labour for farm operations. The study recommends public policies that ensure provision of infrastructure such as roads and boosting farming among rural households. Keywords: Food Insecurity, FGT Index, Rural Households and Nigeri
Prediction of surface roughness in hard milling of AISI D2 tool steel
This paper presents a study of the development of a surface roughness model in end milling of hardened
steel AISI D2 using PVD TiAIN coated carbide cutting tool. The hardness of AISI D2 tool lies within the
range of 56-58 HRe. The independent variables or the primary machining parameters selected for this experiment were the cutting speed, feed, and depth of cut. First and second order models were developed using Response Surface Methodology (RSM). Experiments were conducted within specified ranges of the parameters. Design-Expert 6.0 software was used to develop the surface roughness equations as the predictive models. Analysis of variance (ANOVA) with 95% confidence interval has indicated that the
models are valid in predicting the surface roughness of the part machined under specified condition
Site adaptations of Acanthogyrus (Acanthosentis) tilapiae: Observations through light and scanning electron microscopy
Acanthogyrus (Acanthosentis) tilapiae parasites were collected from the intestines of 300 fish belonging to three tilapia species sourced at the River Nile, Giza, Egypt. The proboscis of the parasite was characterized by three rows of hooks that curved towards the posterior of the body. The first row is supported by unmodified hooks. The parasite tegument has a series of alternative folds and a large number of pores. Sensory ganglia are located on the surface of the proboscis and body. Acanthogyrus (Acanthosentis) tilapiae provokes an aggressive host response indicated by hyperplasia of the intestinal goblet cells and focal eosinophil infiltrations. This acanthocephalan parasite shows a highly modified adaptation to its site of host infection
Quasiclassical Theory of Spontaneous Currents at Surfaces and Interfaces of d-Wave Superconductors
We investigate the properties of spontaneous currents generated at surfaces
and interfaces of d-wave superconductors using the self-consistent
quasiclassical Eilenberger equations. The influence of the roughness and
reflectivity of the boundaries on the spontaneous current are studied. We show
that these have very different effects at the surfaces compared to the
interfaces, which reflects the different nature of the time reversal symmetry
breaking states in these two systems. We find a signature of the ``anomalous
proximity effect'' at rough d-wave interfaces. We also show that the existence
of a subdominant order parameter, which is necessary for time reversal symmetry
breaking at the surface, suppresses the spontaneous current generation due to
proximity effect at the interface between two superconductors. We associate
orbital moments to the spontaneous currents to explain the ``superscreening''
effect, which seems to be present at all ideal d-wave surfaces and interfaces,
where d_{xy} is the favorite subdominant symmetry.Comment: 13 pages, 17 postscript figure
Transient Semi-Circular Lid-Driven Cavity Flow using Non- Uniform Structured Grid Method with Upwind Scheme
In this article, two-dimensional lid-driven cavity flow in a semi-circular cavity is simulated using a non-uniform finite different method with structured grid. NavierStokes and continuity equations are simplified using a non-dimensional streamfunction– vorticity approach. A Reynolds number of 1000 is used and the vorticity and streamfunction contour plot is monitored with convergence criteria of 1x10-7 set to both the vorticity and the streamfunction value. The result shows that the primary vortex moves from the upper left cavity corner to the upper right corner, while the magnitude of the streamfunction grows at the primary vortex center. The primary vortex size decreases steadily as the time increases. This phenomenon is greatly affected by the increasing size of the secondary vortex at the lower left. Slight changes of vortex size are observed as the flow achieves a steady state condition. Validation of the simulation results shows the current value deviation from the established result is less than 5%. In future, it is recommended to use a better numerical method so that the simulation is more stable and so that the calculation time can be reduced
- …