bluuebunny/crossref_metadata_2025_split huggingface dataset:
Energy-Resolved Neutron Imaging using a Delay Line Current-Biased Kinetic-Inductance Detector
Authors: Shishido Hiroaki , Nishimura Kazuma , Dang Vu The , Kojima Kenji M. , Koyama Tomio , Oikawa Kenichi , Harada Masahide , Miyajima Shigeyuki , Hidaka Mutsuo , Oku Takayuki , Soyama Kazuhiko , Aizawa Kazuya , Suzuki Soh Y. , Ishida Takekazu 
Published: August 2020

Abstract
We demonstrate the development of an energy resolved neutron transmission imaging system via a solid-state superconducting detector, called current-biased kinetic-inductance detector (CB-KID). CB-KIDs comprise X and Y superconducting Nb meanderlines with Nb ground plane and a 10B conversion layer, which converts a neutron to two charged particles. High-energy charged particles are able to create quasi-particle hot spots simultaneously in the X and Y meander lines, and thus, the local Cooper pair density in meander lines is reduced temporary. When DC-bias currents are fed into the meander lines, double pairs of voltage pulses are generated at the hot spots and propagate toward both ends of the meander lines as electromagnetic waves. The position of the original hot spot is determined by a difference in arrival times of the two pulses at the two ends for X and Y meander lines, independently. This is so-called the delay-line method, and allows us to reconstruct the two-dimensional neutron transmission image of a test sample with four signal readout lines. We examined the capability of high spatial and energy (wavelength) resolved neutron transmission imaging over the sensor active area of 15 ×15 mm2 for various samples, including biological and metal ones. We also demonstrated the capability for the Bragg edge transmission and an energy-resolved neutron image in which stainless-steel specimens were discriminating from other specimens.
Theory for the response of a superconducting kinetic inductance detector to an electromagnetic wave packet
Authors: Koyama T , Ishida T 
Published: August 2020

Abstract
Voltage pulses generated by local heating due to the irradiation of an electromagnetic (EM) wave packet in a superconducting current-biased kinetic inductance detector are theoretically investigated on the basis of our previous theory [J. Phys. Conf. Ser.
1293, 012050]. The growth and decay of a hot spot created by an EM wave packet is described with the heat diffusion equation coupled with the time-dependent Ginzburg-Landau (TDGL) equation. Variation in the kinetic inductance of the current-biased stripline in the detector induced by a hot spot is explicitly derived. We clarify the characteristic feature in the shape of the voltage pulses.
Kinetic inductance neutron detector operated at near critical temperature
Authors: Dang Vu The , Nishimura Kazuma , Shishido Hiroaki , Harada Masahide , Oikawa Kenichi , Miyajima Shigeyuki , Hidaka Mutsuo , Oku Takayuki , Soyama Kazuhiko , Aizawa Kazuya , Kojima Kenji M , Koyama Tomio , Malins Alex , Machida Masahiko , Ishida Takekazu 
Published: August 2020

Abstract
We previously succeeded in constructing and demonstrating the capability of a neutron imaging system based on a superconducting current-biased kinetic inductance detector (CB-KID). In the present work, we systematically studied the characteristics of the superconducting neutron detector to improve the spatial resolution and detection efficiency. We found that the number of neutron detection events with CB-KID remarkably increased when the detector temperature increased from 4 K to the critical temperature T
c. We observed systematic changes of neutron signals as a function of the detector temperature from 4 K to T
c. We evaluated the detection efficiency of the CB-KID detector, and compared with PHITS Monte Carlo simulations, which modeled the sequential physical processes for the 10B(n,α)7Li reaction, the transport dynamics, and the energy deposition by particles including neutrons, 4He particles, 7Li particles, photons, and electrons.
Development of scanning SQUID microscope system and its applications on geological samples: A case study on marine ferromanganese crust
Authors: Oda H , Kawai J , Usui A , Yamamoto Y , Noguchi A , Miyagi I , Miyamoto M , Fujihira J , Sato M 
Published: August 2020

Abstract
We present developments and applications of a high resolution scanning superconducting quantum interference device (SQUID) microscope for imaging magnetic field of geological samples at room temperature. A directly coupled low-temperature SQUID with a 200 μm × 200 μm pickup loop was mounted on a sapphire rod and separated from room temperature by a sapphire window. The environmental noise of the SQUID was successfully reduced by subtracting the signal of an additional reference SQUID placed inside a cryostat. The resulting system noise level was estimated to be about 50 pT. A geological thin section could be placed on a non-magnetic sample holder with an XYZ stage for scanning in an area of 100 mm × 100 mm. The minimum achievable distance from the SQUID to the sample is measured as ∼200 µm. An application of the SSM to a marine ferromanganese crust successfully provided beautiful stripe patterns in the magnetic images. The patterns could be correlated to the history of geomagnetic field reversals. The boundaries of the magnetic polarity domains were useful guides for the estimation of the deposition age by correlation with the standard geomagnetic polarity timescale. The established age model gave an average growth rate of ∼2.7 mm/Ma, which is consistent with that obtained by radiometric dating using 10Be (∼2.6 mm/Ma).
Electronic Design Automation tools for superconducting circuits
Authors: Fourie Coenrad J 
Published: August 2020

Abstract
Superconducting integrated circuits have long been completely handcrafted or at best designed with a loose collection of tools that require manual manipulation of data and design transfer between tools. Electronic Design Automation (EDA) software development requires significant investment of resources to track the evolution of integrated circuit fabrication processes, which has only been possible commercially for highly successful semiconductor integrated circuit processes. The IARPA SuperTools project which started in 2017 is the largest known investment to date made in superconducting EDA tool development. SuperTools is divided into two main categories: high-level tools for the synthesis of digital logic circuits, clock networks and placed-and-routed layouts for systems such as processors with millions of logic gates; and physical-level tools for the design, simulation, optimisation, verification, layout and parameter extraction of devices and digital logic cells with the inclusion of fabrication process simulation. In this paper the modules developed for the ColdFlux project under SuperTools are discussed from device modelling to chip tape-out. Progress on parameter extraction tools is highlighted.
A two-step routing method with wire length budgeting for PTL routing of SFQ logic circuits
Authors: Kitamura K , Takagi K , Takagi N 
Published: August 2020

Abstract
A PTL routing method for large-scale SFQ logic circuits is proposed. In this method, a routing problem is solved in two steps; global routing and detailed routing. In the global routing, a routing region is split into rectangular subregions and paths connecting them are obtained. Wire length budgeting is introduced into the global routing for allocating sufficient amount of routing resources to each net considering wire length matching in the detailed routing. In the detailed routing, exact wiring routes are determined based on a solution of the global routing and wire length matching is performed at each subregion. The global routing with wire length budgeting is formulated and an algorithm for it is proposed. In the proposed global routing algorithm, initial routes are searched at first using the rip-up and reroute technique, and then, routing resource distribution is calculated by constructing a flow-graph and solving a max-flow problem. If distribution of routing resources fails, global route extension is conducted to allocate additional routing resources to nets. The routing resource distribution and the global route extension are repeated until sufficient resources are allocated to all nets. As a design example, a 16 bit Sklansky adder was designed using the proposed method. Wire length matching in detailed routing was succeeded and the target frequency of 50 GHz was achieved.
Prototyping new type Bi2Sr2CaCu2O8+x devices using a consumer-oriented inkjet printer
Authors: Yamada Y , Okamoto T 
Published: August 2020

Abstract
We have tried the microfabrication of Bi2Sr2CaCu2O8+x (Bi2212) thin films. The thin films were prepared by the metal-organic decomposition method. The photoresist was printed on the thin films using a consumer-oriented inkjet printer. Filling a black cartridge with resist diluted 3 times with ethanol and printing with 80% black can minimize both the scattering of the resist and the areas where the resist is not on. After etching the thin films with citric acid, the photoresist was stripped with NaOH. Under the printing and etching conditions in this report, the resist width was about 0.05 mm wider than the desired width, and the undercut width was about 0.08 mm. We succeeded in forming a bridge of about 75 μm.
Complex research of the unclosed HTS shield for improving homogeneity of the magnetic field
Authors: Kulikov E , Dorofeev G L , Kozlowski K , Tomków L , Drobin V M 
Published: August 2020

Abstract
Homogeneous magnetic fields are required in different applications. The resolution of MRI techniques depends on the quality of the magnetic field, as well as the efficiency of electron cooling systems used at particle accelerators. Unclosed magnetic shield made of superconducting tapes is able to nullify the radial component of a solenoidal magnetic field, forming the long region of the homogeneous magnetic field. The shield is a lengthwise winding made from YBCO tapes are wound along a carcass generatrix. Then it is positioned coaxially inside an electromagnet. The measurements were carried out under quasistationary conditions, magnetic fields up to 1 kG at 77K. This paper discusses the design of the superconducting shield and presents experimental and numerical studies into the homogeneity of the magnetic field in solenoids with the superconducting shield.
Experimental study on temperature distribution measurement of an optical fiber encapsulated coil in liquid nitrogen
Authors: Lv Y Y , Jiang J J , Wang L B , Li Z Y , Hong Z Y 
Published: August 2020

Abstract
Fast quench detection technique is extremely important for high temperature superconducting (HTS) applications, especially HTS magnets. As one of potential candidates, the method based on distributed optical fiber sensors were suggested recently. To keep HTS tape structure intact and reduce thermal propagation time from HTS tape to optical fiber, a method that optical fiber is encapsulated in HTS tape edge along the length direction could be satisfied. In this paper, an optical fiber encapsulated tape (OF-tape) was successfully fabricated. To verify the feasibility of temperature measurement for this tape, a coil wound with OF-tape and a distributed temperature sensor (DTS) system were prepared. The main results show that temperature of the coil can be measured accurately in air and in liquid nitrogen. After suffering impulse currents with peak values of 570 A and durations of 1, 2, and 3 s, temperature rises of the coil are 98.5, 137.8, and 271.0 K, respectively. Moreover, the highest temperature appears from 3.6 m to 21.7 m of the coil when it suffers the impulse current of 460 A/3 s.
Heat leak of cryogenic pipe for superconducting dc power transmission line (SCDC)
Authors: Yamaguchi Sataro , Kanda Masae , Ivanov Yury 
Published: August 2020

Abstract
Main loss of the superconducting DC power transmission line (SCDC) comes from the heat leak of the cryogenic pipe because of no internal heat generation in the dc cable. It should be minimized to realize the high performance of SCDC. The heat leak of the cryogenic pipe depends on the ambient temperature, and when it is high, the heat leak is also high. Therefore, we estimated the sensitivity of the heat leak for the ambient temperature at first, and estimated the effect of this for the distance between the cryogenic stations. The major process of the heat leak is the heat transfer through the multi-layer insulation (MLI) and the second process is the thermal conduction of the support leg of the inner pipe in our design. The MLI is made from the multi-layers of the aluminium-coated thin film (ACTF) with the spacer, and the support leg is made of the glass fiber reinforced plastic (GFRP). The aluminium layer reflects the infrared light highly to reduce the heat transfer by radiation, and the spacer can prevent the direct contact with the ACTF. Therefore, the weight of the MLI should be light to minimize the thermal transfer of the spacer. We tested various types of MLI to find the optimum MLI structure experimentally. Usually, the measurement of the heat leak is not easy in an actual cryogenic pipe and we need the long experiment time and a relatively large instrument to evaluate the heat leak. However, since we need to evaluate many MLIs, we developed the different way to estimate the heat leak through the MLI by a small experimental device. To find the optimum MLI, we started to test three samples of the MLI supplied from Kaneka Corp., and measured the temperature of the MLI. Since the heat capacity of MLI is low, we used the 50-micron meters thermocouple (TC) and attached it to measure the temperature of the MLI carefully. The result of the experiment shows that we found that the net type of the spacer is better than the spacer used in Ishikari project, and the heat leak would be half of the Ishikari project. We also measured the thermal conductivity of two test samples of GFRP to reduce the heat conductions of the support leg. The thermal conduction of these two GFRPs are almost 1/2 to 1/4 of the recommended values of the NIST. Because of these efforts to reduce the heat leak of the cryogenic pipe, we can expect the target values of the heat leak is a half of the Ishikari project in the next project, and if we can reach this value, we can extend the distance of the cryogenic stations to ∼100km actually on the earth. The values of this distance is important to transfer the electricity for all over the world like the gas and oil pipeline in the present time.
Heat leak measurement of the cryogenic pipe for the superconducting power transmission at different surface temperatures
Authors: Watanabe Hirofumi , Takeuchi Toru , Miyake Katsuya , Yamaguchi Satarou 
Published: August 2020

Abstract
The heat leak of the cryogenic pipe constituting a transmission line of the superconducting power transmission depends on the surface temperature of the cryogenic pipe, because the heat leak is mainly caused by the radiative and conductive heat transfers. The heat leak of the cryogenic pipe for the superconducting power transmission has been measured with respect to its surface temperature ranging from -3 to 53 °C to investigate the effect of the surface temperature variation and to obtain data for the installation of cables in different places with different environmental conditions. The cryogenic pipe used for the measurements has two inner pipes, called cable pipe and return pipe, in a single outer pipe. For the cable pipe the heat leak of 0.82 W/m at -3 °C increases to 1.27 W/m at 51°C, while for the return pipe the heat leak of 0.46 W/m at -3 °C increases to 0.94 W/m at 51°C. The heat leak increases smoothly with the surface temperature, which can be well reproduced by a formula based on the temperature dependences of the radiative and conductive heat transfers. The heat leak by the conductive heat transfer is discussed based on the experiments and the calculations.
Evaluation of the operation efficiency of implemented highway project
Authors: Ellk Dunya Sahib , Adil Hanan 
Published: August 2020

Abstract
Traffic congestion is a considerable problem that big cities face and has undesirable consequences such as uncomfortable usage of roads, car accidents, worsening of performance of road networks, air pollution and economic issues. Therefore, governments have been planning to solve this problem and reduce the traffic congestion level (1). Recently, it is observed that Baghdad city has suffered from severe daily traffic congestion. The key reasons include the great increase in the number of private cars and the deterioration of public transit services. The planners tend to building new highways, such as overpasses and underpasses, to accommodate the increase in the traffic volume and alleviate congestion. However, it is noted that this problem has been persisted in several locations in Baghdad city even after the operation of the new overpasses and underpasses. It means that the implemented projects have not efficient in achieving their aim. Thus, it has been important to investigate the reasons behind this failure. This study focused on evaluating the efficiency performance of two selected overpasses at the Al-Shaab quarter and at the Bab al-Muadam place as the congestion is still in its highest level there, especially at peak hours. A traffic analysis study was accomplished involving a collection of traffic data in the two locations and analysing them using the HCS2000 program in order to specify the reasons of poor performance. It was found that level of service is F after construction, therefore the paper proposed number of alternative suggestions to develop their performance.
Stability analysis of geosynthically piled foundation earth dam; a case study: Sombar dam
Authors: Akhtarpour Ali , Mahmood Mohammed Sh , Alali Ameer 
Published: August 2020

Abstract
The use of drains in a regular grid and required depth in the soil are reduced the time of drainage process and soil consolidation considerably. Sombar dam is a project to use optimum seawater flow and flood control to provide agricultural water as well as to develop the area under cultivation of the existing dam in Gholaman village as well as the city of Raz in north Khorasan province, Iran. The purpose of this research is assessing the influence of vertical geotextile drainage (length and spacing), for different permeability ratios (ky/kx), on the dam stability during the construction using GeoStudio2012 software. The analysis is performed using models of Mohr-Coulomb and modified cam clay. The results show that there is a significant effect of the drains for the studied parameters. After 24 months with maximum drain depth (24m) and minimum drain spacing (2m) the values of the studied parameters are closer to each other.
Futurity scenario of water resources management in Bahr An-Najaf basin in Iraq
Authors: Omran Hassan Ali , Mahmood Mohammed Sh , Kadhem Ali Abbas 
Published: August 2020

Abstract
By using water resources management techniques for planning, improvement and supply, optimal use of the available water inside Iraq will achieve. This paper focuses on the management of water resources in Bahr Al-Najaf region, Najaf, Iraq for the expected future water resources and demands. These resources and demands are adopted with continued demands from the current situation to study the adequacy of water resource quantities in the study area. The authors try to answer the question that is the resources are enough or must provide other quantities of surface water and groundwater? and what amount? The results of the study indicate that there is a shortage that occurs in the futurity scenario of 55Mm3 and it is related to the tourism sector. The shortage of water quantity of the futurity scenario can be covered by drilling new wells by portion reach to 85%.
Evaluation of Hybrid-Modified Asphalt Mixtures Performance Using Bending Beam Rheometer
Authors: Abed Mohammed A , Abed Alaa H 
Published: August 2020

AbstractThis study elucidate a test methodology to execute the creep tests to assess the performance of the hot asphalt mixture (HMA) beams by utilizing the bending beam rheometer (BBR) and explain the most issues related to performing this test. Firstly, a comprehensive samples preparation technique has illustrated and the experimental data were presented to evaluate the reliability of this technique. To perform this test, one aggregate gradation and two types of polymer modifiers with three percent of modification for each type of polymers were used. However, experimental results showed that decreasing the testing temperature by an increment of 10 oC can reduce the deflection by 95.6, and 99.13%. Decreasing the temperature from 25 to 15 and 10 oC can increase the creep stiffness by 12.6 and 36.6 time. Which indicate that temperature was a predominant factor affecting the most responses of the hot asphalt Mixtures. besides polymer modification significant effect on the stiffness which is clear that using 4, 6, and 8 % of SBS can increase the creep stiffness by 9.8, 44.6 and 196 % respectively. Although, the hybrid modification had been increased the creep stiffness for asphalt mixtures by 16.3, 72.5, and 186.7% respectively.
Monte carlo simulation for stability of finite slope subjected to earthquake loading
Authors: Al-Gharrawi Asaad M. B. , Abdul-Husain Husain Ali 
Published: August 2020

Abstract
Analysis of finite slopes is a common practical problem which faces the geotechnical engineering. The aim of the slope analysis is to predict the safety factor against shear failure of the slope which is the ratio between the resisting and the disturbing forces developed along an assumed slip surface. Presence of seismic forces due earthquake lead to more critical situation. The deterministic approaches are employed for this purpose. These approaches do not take into account the uncertainty related to soil properties and/or seismic loads in their procedures. In the present work, a probabilistic approach is adopted using the Monte Carlo simulation technique to study the effect of uncertainty due to soil properties (unit weight, angle of internal friction and cohesion) and seismic accelerations (vertical and horizontal). The results of the work demonstrate that the use of probabilistic approach will yield more accurate results for estimating the safety factor and then economic design of the slope. Also, the results reveal that the statistical properties for the soil shear strength parameters have significant impact on the standard deviation of the output (factor of safety), while the soil unit weight and horizontal acceleration have small effect. However, the vertical acceleration has no effect on it. On other hand, the mean of the output distribution does not affect by the statistical parameters of all input variables. All cases simulated in this study give reliability index (RI) less than 3. Hence, RI values indicate that there are unsatisfactory level of safety for the slope subjected to seismic loading. Finally, the soil shear strength parameters have the same positive significant impact on the safety factor. But, the soil properties and the coefficient of the horizontal acceleration should be selected carefully in the stability analysis due to the effect of their uncertainty on the analysis results.