• Progress in Superconductivity and Cryogenics
• /
• v.21 no.2
• /
• pp.45-49
• /
• 2019

This paper reports comparison between analytic and numerical simulation approaches for calculation of screening current and screening current induced field in a high temperature superconductor magnet. Bean slab model is adopted to calculate screening current and SCF analytically, while the finite element method numerically. A case study of screening current and SCF calculation are conducted with a magnet, a 7 T 68 mm cold-bore multi-width no-insulation GdBCO magnet built and tested by Massachusetts Institute of Technology Francis Bitter Magnet Laboratory. In this study, we assume the magnet is dunked in liquid nitrogen at 77 K. Furthermore, the simulation results are compared in terms of computation time and accuracy. Finally, discussion on the different methods together with the comparison between the calculations and experiment is provided.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.50 no.4
• /
• pp.276-280
• /
• 2005

Low temperature is one of the most severe abiotic stress factors limiting growth, productivity and distribution of winter cereals. Reliable field screening method, which can detect small differences in winter survival, is important for the effective selection and development of plants to identity superior cold tolerant winter cereal genotypes. This study was undertaken to provide improved screening method of winter hardiness in the field by increasing the accuracy in evaluating winter hardiness of barley (Hordeum vulgare L.). We introduced furrow in field screening of winter survival. By sowing the plants at the ridge and base, we could minimize the effect of topographic variation in a field by giving higher and lower level of stress at the same time. This method could be used by breeders to conduct accurate evaluation of winter hardiness by selecting the better treatment, which shows close to normal distribution, among the winter survival rate from the ridge, base and mean survival rate of the two in a screening field.

• 한국초전도학회:학술대회논문집
• /
• 2009.07a
• /
• pp.24-24
• /
• 2009

• Progress in Superconductivity and Cryogenics
• /
• v.2 no.1
• /
• pp.31-34
• /
• 2000

this paper deals with the initial magnetic field decay for a large scale superconducting magnet e.g. NMR/MRI magnet. The high resolution image can not be obained during the periods of the initial field decay. It is known that all superconducting materials have the property of diamagnetism. This diamagnetism is usually explained with the concept of screening current. We assumed that the existence of the screening currebt. we assumed that the existence of the screening current makes the current distribution in the superconducting wire non-uniform. And the initial magnetic field decay is caused steady current state in the view of its pattern. The initial magnetic field decay is caused by the change of the current distribution between the energizing state and persistent current mode. in this paper the theoretical analysis for the current distributions has been introduced for each state. The experiments have been carried out to verify transport currents in order to veperiments, it small at the higher transport current.

• The Korean Journal of Ceramics
• /
• v.5 no.4
• /
• pp.386-389
• /
• 1999

Effect of high voltage screening was examined on mechanical strength of titania ceramics with two different surface roughness. Roughly finished sample showed degraded mechanical strength meaning that the introduced flaw played the role of starting point of mechanical fracture. On such sample, electrically weak parts were eliminated by applying a screening field. Mechanical strength measurement on survived parts revealed that after screening the Weibull plots bended to become a convex curve while plots at high strength region were almost the same. This result means that relatively low mechanical strength parts were eliminated by the electrical method. As a result the Weibull modulus calculated from all the data increased, demonstrating the effect of high voltage screening on titania ceramics containing fracture controlling surface flaws. Roles of the surface flaw such as a common weak spot for both failures are disscussed in relation to the electric field concentration similar to that of mechanical stress.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.52 no.2
• /
• pp.129-133
• /
• 2007

To breed virus resistant rice variety, developing an efficient screening method is the most important. Two screening methods such as field screening and tray screening method have been used, but the efficiency of the field screening method is too low because of environment factors and the that of the tray screening method is good but screening capability is limited with only $200{\sim}300$ lines per year. To overcome those problems, mass screening method using screen house was developed. Barely as host plant of vector insect was grown in screen house in winter season. Then viruliferous insects are spread in the first spring of the initiation year and sustain them annually. Screening of virus resistance was tested two times in a year, the first screening was from April to June and the second from July to September. The virus infected rate of each susceptible varieties was increased to 92% for RSV and 100% for RDV from the second year. Also, this method can evaluate as many as $1,500{\sim}2,000$ pedigree lines in one time compared with the tray screening method. The result indicates that the mass screening method using screen house, which combines the advantages of the field and tray screening methods, is proven to be more efficient and reliable.

• Korean Journal Plant Pathology
• /
• v.1 no.2
• /
• pp.115-121
• /
• 1985

To improve methods of screening rice cultivars with field resistance to bacterial leaf blight, testing plant inoculation and neighbor plant inoculation were compared by using 33 rice cultivars. In the testing plant inoculation method, field resistance was evaluated by measuring the leaf areas diseased on the new leaves expanded after the inoculation. Varietal differences in field resistance were recognized more clearly by the testing plant inoculation method than by the neighbor plant inoculation method. Highly significant correlation was observed between the results of the two methods. Some rice cultivars such as, Seomjin, Hangangchal, Taebaeg, Samgang, Milyang 42, Asominori, Java 14, Chugoku 45 and 70X-46 showed remarkable field resistance to bacterial leaf blight. The testing plant inoculation method appeared desirable for screening rice cultivars for the qualitative and field resistance to bacterial leaf blight because of using less labor and less field area than neighbor plant inoculation.

• Journal of Korean Society for Quality Management
• /
• v.33 no.4
• /
• pp.88-95
• /
• 2005

Multistage screening is a common practice when a component has a critical effect on the function of the assembly. A defect in a component might incur malfunction of an electronic device, resulting in a great amount of loss. Multistage screening, including duplicated screening inspections, may provide a good solution for this problem when inspection errors are present. In the company studied here, the manufacturing process of the multiple layer chip capacitor includes two-stage screening. In the first stage, screening inspection is performed repeatedly until no defects are found in the lot. In the second stage, sampling inspection is performed by a group of experts prior to shipment. In this article, we review the procedure used in the field and suggest a revised model of the multiple screening procedure and solution method for this situation. The usefulness of the proposed model is discussed through a practical example.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.15 no.9
• /
• pp.3458-3481
• /
• 2021

Existing methods for blind identification of linear block codes without a candidate set are mainly built on the Gauss elimination process. However, the fault tolerance will fall short when the intercepted bit error rate (BER) is too high. To address this issue, we apply the reverse algebra approach and propose a novel "two-step-screening" algorithm by solving the linear error equations on the binary Galois field, or GF(2). In the first step, a recursive matrix partition is implemented to solve the system linear error equations where the coefficient matrix is constructed by the full codewords which come from the intercepted noisy bitstream. This process is repeated to derive all those possible parity-checks. In the second step, a check matrix constructed by the intercepted codewords is applied to find the correct parity-checks out of all possible parity-checks solutions. This novel "two-step-screening" algorithm can be used in different codes like Hamming codes, BCH codes, LDPC codes, and quasi-cyclic LDPC codes. The simulation results have shown that it can highly improve the fault tolerance ability compared to the existing Gauss elimination process-based algorithms.

• Journal of Genetic Medicine
• /
• v.5 no.1
• /
• pp.7-14
• /
• 2008

Twenty years have passed since a prenatal screening for Down syndrome and neural tube defect was applied to obstetric field. The Quad test (AFP, hCG, uE3, Inhibin-A) of the second trimester and the combination test (PAPP-A, hCG, NT) of the first trimester became popular now. The recent trend of prenatal screening is to combine these two screening tests together in order to increase a detection rate of Down syndrome. Three types of screening methods are introduced as follows; integrated test, sequential test and contingent test. In addition to combination of each test, an incorporation of characteristic ultrasound findings of Down syndrome is suggested for its risk calculation. The absence of fetal nasal bone would be a very useful marker especially in the first trimester screening test. According to a change of way calculating risk of Down syndrome, obstetrician's role will be more increased not by passive participation, but by active participation using ultrasound in risk calculation.