• Journal of Magnetics
• /
• v.10 no.3
• /
• pp.103-107
• /
• 2005

Magnetotransport is a prerequisite to realization of electronic operation of spintronic devices and it would be more useful if realized at room temperature. The effects of Be codoping on GaMnAs on magnetotransport were investigated. Mn flux was varied for growth of precipitated GaMnAs layers under a Be flux for degenerate doping via low-temperature molecular beam epitaxy. Magnetotransport as well as ferromagnetism at room temperature were realized in the precipitated GaAs:(Mn,Be) layers. Codoping of Be was shown to promote formation of MnGa clusters, and annealing process further stabilized the cluster phases. The room-temperature magnetic properties of the layers originate from the ferromagnetic clusters of MnGa and MnAs embedded in GaAs. The degenerately doped metallic GaAs matrix allowed the visualization of the magnetotransport through anomalous Hall effect.

• Proceedings of the KIEE Conference
• /
• 2000.07b
• /
• pp.1083-1086
• /
• 2000

In this paper a development of 10KVA series-parallel compensated UPS is shown, which has high input power factor and sinusoidal output voltage regulation capability. Compared to conventional cascaded UPS, the size can be reduced significantly with high quality input and output waveforms. The front converter and the main inverter can be considered decoupled, hence the front converter and the main inverter can be designed independent of each other. In this paper, analysis and experimental results for an 10 KVA prototype are presented.

• Nuclear Engineering and Technology
• /
• v.42 no.6
• /
• pp.662-669
• /
• 2010

To develop the manufacturing methods for the blanket first wall (FW) of the International Thermonuclear Experimental Reactor (ITER) and to verify the integrity of the joint, Be/Cu mockups were fabricated and tested at the KoHLT-1 (Korea Heat Load Test facility), a graphite heater facility located at the Korea Atomic Energy Research Institute (KAERI). Since Be and Cu joining is the focus of the present study, the fabricated mockups had a CuCrZr heat sink joined with three Be tiles as an armor material, unlike the original ITER blanket FW, which has a stainless steel structure and coolant tubes. Hot isostatic pressing (HIP) was carried out at $580^{\circ}C$ and 100 MPa for 2 hours as the method for Be/Cu joining. Three interlayers, namely, $1{\mu}mCr/10{\mu}mCu$, $1{\mu}mTi/0.5{\mu}mCr/10{\mu}mCu$, and $5{\mu}mTi/10{\mu}mCu$ were applied as a coating to the Be tiles by a physical vapor deposition (PVD) method. A shear test was performed with the specimens, which were fabricated by the same methods as those used to fabricate the mockups. The average values were 125 MPa to 180 MPa, and the samples with the $1{\mu}mCr/10{\mu}mCu$ interlayer showed the lowest value. No defect or delamination was found in the joints of the mockups by the developed ultrasonic test using a flat-type probe with a 10 MHz frequency and a 0.25 inch diameter. High heat flux (HHF) tests were performed at $1.0\;MW/m^2$ heat flux for each mockup using the given conditions, and the results were analyzed by ANSYS-CFX code. For the test criteria, an expected fatigue lifetime about 1,000 cycles was obtained by analysis with ANSYS-mechanical code. Mockups using the interlayers of $1{\mu}mTi/0.5{\mu}mCr/10{\mu}mCu$ and $5{\mu}mTi/10{\mu}mCu$ survived up to 1,100 cycles over the required number of cycles. However, one of the Be tiles in the other two mockups using the $1{\mu}mCr/10{\mu}mCu$ interlayer was detached during the screening test, and others were detached by discharge after 862 cycles. The integrity of the joints using the proposed interlayers was proven by the HHF test, but the other interlayer requires more study before it can be used for the joining of Be to Cu. Moreover, it was confirmed that the measured temperatures agreed well with the analysis temperatures, which were used to estimate the lifetime and that the developed facility showed its capability of the long time operation.

• Journal of the Korea Society of Computer and Information
• /
• v.22 no.10
• /
• pp.151-157
• /
• 2017

In the case of uploading privacy information of an information owner in the Internet, the information owner may want to deliver the privacy information itself or remove such information from the search list in order to prevent third parties from accessing the privacy information of the information owner. Such a right to be forgotten may collide with the freedom of expression of a third party. The right to be forgotten, which originates from the self-determination right on privacy information based on Article 10 and 17 of the Constitution and the freedom of expression, which is based on Article 21 thereof are all relative basic rights and are both limited by Item 2 under Article 37 of the same law, which is the general limitation provision for the basic rights. Therefore, when the right to be forgotten and the freedom of expression collides, it is not possible to give priority to one of the those unilaterally. It depends on the nature of the case at hand to find a natural balance for the harmonious solution for both parties. The criteria can be the sensitivity to the privacy of the information owner caused by the disclose of the privacy information, the public benefits such information may serve, the social common good that could be expected by the disclosure of the privacy information and the damages suffered in terms of the personal interest caused by the disclosure of the information, in a comprehensive manner.

• Korean Journal of Materials Research
• /
• v.27 no.12
• /
• pp.695-698
• /
• 2017

ZnMgBeGaO/Ag/ZnMgBeGaO multilayer structures were sputter grown and characterized in detail. Results indicated that the electrical properties of the ZnMgBeGaO films were significantly improved by inserting an Ag layer with proper thickness (~ 10 nm). Structures with thicker Ag films showed much lower optical transmission, although the electrical conductivity was further improved. It was also observed that the electrical properties of the multilayer structure were sizably improved by annealing in vacuum (~35 % at $300^{\circ}C$). The optimum ZnMgBeGaO(20nm)/Ag(10nm)/ZnMgBeGaO(20nm) structure exhibited an electrical resistivity of ${\sim}2.6{\times}10^{-5}{\Omega}cm$ (after annealing), energy bandgap of ~3.75 eV, and optical transmittance of 65 % ~ 95 % over the visible wavelength range, representing a significant improvement in characteristics versus previously reported transparent conductive materials.

• Radiation Oncology Journal
• /
• v.6 no.2
• /
• pp.151-154
• /
• 1988

To answer the question whether last clonogenic cell should be eradicated for the tumor to be controlled, radiation tumor control study was performed using microscopic tumors of variable sizes ranging from 101 to 10s tumor cells. $TCD_{50}'s$ estimated from experimental data were 14.8, 27. 1, 42.4, 49.9 and 65.5 Gy for $10^1,\;10^2,\;10^3,\;10^4\;and\;10^4$ tumor cells, respectively. Theoretical calculations, assuming that all the clonogenic cells should be inactivated, were 15.65, 8.50, 40.97, 53.41 and 65.85 Gy. From this well matched data, it can be concluded that all the clonogenic cells should be eradicated for tumor control, at least in this tumor model.

• Transactions of Materials Processing
• /
• v.10 no.7
• /
• pp.565-572
• /
• 2001

It is well known that a multicomponent $Zr_{4l.2}Ti_{13.8}Cu_{12.5}Ni_{10}Be_{22.5}$ bulk metallic glass alloy shows good bulk glass forming ability due to its high resistance to crystallization in the undercooled liquid state. DSC and XRD have been performed to confirm the amorphous structure of the master alloy. To investigate the mechanical properties and deformation behavior of the bulk metallic $Zr_{4l.2}Ti_{13.8}Cu_{12.5}Ni_{10}Be_{22.5}$ alloy, a series of compression tests has been carried out at the temperatures ranging from $351^{\circ}C$ to $461^{\circ}C$at the various initial strain rates from $2{\times}10^4s^1$ to $2{\times}10^2s^1$. Three types of nominal stress-strain curves have been identified such as linear stress-strain relationship meaning fracture at maximum stress, plastic deformation including stress overshoot and steady-state flow, plastic deformation without stress overshoot depending on the strain rate and test temperature. Also DSC analysis for the compressed specimens was carried out to investigate the change of structure, thermal stability and crystallization behavior for the various test conditions.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2006.03a
• /
• pp.1032-1037
• /
• 2006

This thesis studied effects of the excavation around railroads on the deformation of the lateral ground and neighboring railroads. The conclusions of the study are as follows. 1. When the depth of excavationis 10m, the influential area should be 35m for soft clay, 20m for normal clay, 15m for hard clay, 15m for loose sand, 12m for slightly dense sand, and 8m for dense sand. 2. When the influential area is 10m, the allowable excavation depth should be 2.5m for soft clay, 4.8m for normal clay, 7.5m for hard clay, 7.2m for loose sand, 8.8m for slightly dense sand, and 10m for dense sand. 3. When the influential area is 20m, the allowable excavation depth should be 4.5m for soft clay, and up to 10m for the other five kinds of soil. 4. When the influential area is 30m, the allowable excavation depth should be 7.5m for soft clay, and up to 10m for the other five kinds of soil. 5. When the influential area is 35m, the allowable excavation depth should be up to 10m for all kinds of soil.

• Tunnel and Underground Space
• /
• v.10 no.3
• /
• pp.316-319
• /
• 2000

Stress variation due to size variation and the eccentricity of ring type tensile specimen was analyzed by FLAC program. To get the stable tensile strength the ratio of inner to outer ring diameter should be within a certain range. Diameter ratio of 0.3 was suggested to be adequate. It seemed to be difficult to determine the tensile strength because of stress distortion if eccentricity exceeded some limit. To limit the error in 10%, lateral and axial eccentricity was analyzed to be in the limits of 3% and 10%, respectively.

• International Commerce and Information Review
• /
• v.10 no.4
• /
• pp.395-416
• /
• 2008

The advance information for oceangoing cargoes destined to th United States enable CBP to evaluate the potential risk of smuggling WMD and to facilitate the prompt release of legitimate cargo following its arrival in the Unites States. On January 1, 2008, CBP promulgate regulations, also known as 10+2 rule, to require the electronic transmission of additional data elements for improved high-risk targeting, including appropriate security elements of entry data for cargo destined to the United States by vessel prior to loading of such cargo on vessels at foreign seaports. The potential impact to an importer's international supply chain will be as follows ; Firstly, importers will take incremental supply chain costs and filing costs. Secondly, anticipate delay in shipment of containerized cargo. Thirdly, importers could be charged fines if they fail to file and file inaccurate or missing data. Companies exporting to the United States should be interested in 10+2 rule, analyze their current processes and procedures to ensure that they are prepared to handle the additional filing requirements of 10+2 rule. And they should focus on how 10+2 impacts their supply chain in terms of costs and sourcing. They will be necessary to revise service legal agreements with their forwarders, customs brokers or carriers in order to meet filing requirements of 10+2 rule.