• Progress in Superconductivity and Cryogenics
• /
• v.16 no.1
• /
• pp.1-5
• /
• 2014

We calculated the resonance tunneling energy band in the BCS gap for Type-II superconductor in which periodic potential is generated by external magnetic flux. In this model, penetrating magnetic flux was assumed to be in a fixed lattice state which is not moving by an external force. We observed the existence of two subbands when we used the same parameters as for the $Nd_{1.85}Ce_{0.15}CuO_X$ thin film experiment. The voltages at which the regions of negative differential resistivity (NDR) started after the resonant tunneling ended were in a good agreement with the experimental data in the field region of 1 T - 2.2 T, but not in the high field regions. Discrepancy occurred in the high field region is considered to be caused by that the potential barrier could not be maintained because the current induced by resonant tunneling exceeds the superconducting critical current. In order to have better agreement in the low field region, more concrete designing of the potential rather than a simple square well used in the calculation might be needed. Based on this result, we can predict an occurrence of the electromagnetic radiation of as much difference of energy caused by the 2nd order resonant tunneling in which electrons transit from the 2nd band to the 1st band in the potential wells.

• Publications of The Korean Astronomical Society
• /
• v.30 no.2
• /
• pp.507-509
• /
• 2015

This work aims to study the evolution of galaxies, located in the dense environment of the NGC 4095 compact group, which have recession velocities 6,000 < v ($km\;s^{-1}$) < 8,000. Imaging observations for BV $R_c$ broad-band, and [$S\small{II}$] and red-continuum narrow-band were carried out with the 2.4 m Thai National Telescope (TNT) at Doi Inthanon, Chiang Mai, Thailand. The sample contains 13 galaxies, consisting of 8 spirals, 4 ellipticals and 1 irregular morphological type. Late type galaxies tend to be bluer than early type galaxies. The results show that most of the late type galaxies have ongoing star formation activity, which could be triggered by galaxy-galaxy or tidal interactions, and that young massive stars in these galaxies cause their colors to be bluer than the early type galaxies.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.10A
• /
• pp.1015-1022
• /
• 2007

In this paper, dual-band digital codec for UHF(Ultra High Frequency) and MW(Micro Wave) is proposed for an RFID reader system. Most RFID systems have been supported only one protocol. But, There are many protocols of each bandwidth. Especially, UHF bandwidth which is widely used on the globe consists of A,B,C type, and more standards will be established. Recently, Since an interest about mobile RFID system is increasing, the RFID system with more than one protocol will be need. Therefore, this paper suggests a dual-band digital codec with UHF and MW bands for an RFID reader system. Standards used in this system are 18000-6C and 18000-4 standards. The digital codec is synthesize by the Quartus II compiler. Target device is EPC20Q240C8 which is family of CycloneII. Main Clock is 19.2MHz and elements of FPGA which is used for the system is 18,752.

• Journal of The Korean Astronomical Society
• /
• v.19 no.2
• /
• pp.69-89
• /
• 1986

The global morphology and geometric parameters of 39 barred galaxies are investigated, by using isophote map and isodensity tracings obtained from detailed surface photometry with the Kiso V-band plates. The observed results are as follows: i) There is no strong indication that the ratio of bar length to disk size is correlated with Hubble type, except that the largest bars appear in the SBb galaxies. ii) The mean value of axial ratios of bars is $2.0{\pm}0.4$ and there is a trend that early type galaxies have smaller axial ratios than late type galaxies. iii) About 15% of early type barred galaxies(Sb0-SBb) have triaxial bulges.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.27 no.3
• /
• pp.178-183
• /
• 2014

Recently, various type of nanomaterials such as nanorod, nanowire, nanotube and their core/shell nanostructures have attracted much attention in photocatalyst due to their unique properties. Among them, Type-II core/shell heterostructures have extensively studied because it has exhibited improved electrical and optical properties against their single-component nanostructure. Such structures are expected to offer high absorption efficiency and fast charge transport due to their stepwised energetic combination and large internal surface area. Thus, it has been considered as potential candidates for high efficient photocatalytic activity. In this work, we introduce a novel chemical conversion process to synthesize Type-II ZnO/ZnSe core/shell heterostructures. A plausible conversion mechanism to ZnO/ZnSe core/shell heterostructres was proposed based on SEM, XRD, TEM and XPS analysis. The ZnO/ZnSe heterostructures exhibited excellent photocatalytic activity toward the decomposition of RhB dye compared to the ZnO nanorod arrays due to enhanced light absorption and the type-II cascade band structure.

• Journal of Korean Foot and Ankle Society
• /
• v.15 no.1
• /
• pp.18-21
• /
• 2011

Purpose: To evaluate the clinical and radiological results of internal fixation with tension band wiring for the fracture at the base of fifth metatarsal bone. Materials and Methods: From January 2008 to December 2009, 15 cases with displaced fracture at the base of fifth metatarsal were analyzed and average follow up period was 13.8 months. Lawrence classification was used to classify fracture type. We evaluated clinical results by American Orthopedic Foot Ankle Society (AOFAS) midfoot score and radiological results by union time. Complications was also checked. Results: According to classification, zone I fracture were 11 cases and zone II fracture were 4 cases. Bony union was achieved in all cases after 7 weeks. In the final follow-up, average AOFAS score was 94. There were no complications except hardware irritation. Conclusion: Satisfactory results were obtained after tension band wiring for the fifth Metatarsal base fracture in zone I fracture or comminuted zone II fracture for which it is not easy to be fixed with screw.

• The Academic Congress of Korean Shoulder and Elbow Society
• /
• 2005.03a
• /
• pp.66-66
• /
• 2005

• The Bulletin of The Korean Astronomical Society
• /
• v.30 no.2
• /
• pp.40.2-40.2
• /
• 2005

• Clinics in Shoulder and Elbow
• /
• v.1 no.1
• /
• pp.66-71
• /
• 1998

The fractures of lateral end of clavicle can be treated by conservative or operative treatment, but many authors report the higher rate of non-union with conservative treatment and that the operative treatment is more effective for the type II fractures. The authors reviewed and analysed 15 cases of lateral end fracture of clavicle which had been treated at Department of Orthopedic Surgery, Kyungpook National University Hospital from 1991 to 1996. The results were as follows; 1. Among the 15 patients, male was 6,female 9 and the average age was 46.2 years ranged from 21 to 72 years. 2. According to the classification by Rockwood, type II a was 8 cases and II b was 7 cases. 3. We treated operatively 12 cases, 9 cases with tension band wiring and 3 cases with intramedul-Iary K-wire fixation. And we treated conservatively 3 cases with Velpeau cast, but I case of nonunion was treated with tension band wiring. 4. The average follow-up was 3.2 years ranged from 2.1 to 4.7 years. 5. The functional results were evaluated with Weitzman's classification. 6. In the operatively treated cases, there were 4 cases(30.7%) in excellent, 7 cases(53.8%) in good and 2 cases(15.3%) in fair result. But, in the conservatively treated cases, there were 2 cases in good and I case in poor result, and the poor case did not united and had open reduction and internal fixation. 7. In conclusion, the operative treatment revealed good functional results in most cases (10/12) and early open reduction and internal fixation was better method than conservative treatment.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.2 no.2
• /
• pp.83-94
• /
• 1994

Performance test result on prototype car equipped with low-band type active suspension system is reported. Control theory is explained first. Simulation for feasibility and parameter tuning, control module test using hydraulic exciter and test run, and performance evaluation of the test car on test track are reported successively. Emphasis was put on modification of control theory which caused many unexpected problems in actual implementation.