• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.106.1-106.1
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• 2011

The Cu(In,Ga)Se2 (CIGS) thin film solar cells have been achieved until almost 20% efficiency by NREL. These solar cells include chemically deposited CdS as buffer layer between CIGS absorber layer and ZnO window layer. Although CIGS solar cells with CdS buffer layer show excellent performance, the short wavelength response of CIGS solar cell is limited by narrow CdS band gap of about 2.42 eV. Taking into consideration the environmental aspect, the toxic Cd element should be replaced by a different material. Among Cd-free candidate materials, the CIGS thin film solar cells with ZnS buffer layer seem to be promising with 17.2%(module by showa shell K.K.), 18.6%(small area by NREL). However, ZnS/CIGS solar cells still show lower performance than CdS/CIGS solar cells. There are several reported reasons to reduce the efficiency of ZnS/CIGS solar cells. Nakada reported ZnS thin film had many defects such as stacking faults, pin-holes, so that crytallinity of ZnS thin film is poor, compared to CdS thin film. Additionally, it was known that the hetero-interface between ZnS and CIGS layer made unfavorable band alignment. The unfavorable band alignment hinders electron transport at the heteo-interface. In this study, we focused on growing defect-free ZnS thin film and for favorable band alignment of ZnS/CIGS, bandgap of ZnS and CIGS, valece band structure of ZnS/CIGS were modified. Finally, we verified the photovoltaic properties of ZnS/CIGS solar cells.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.8 s.338
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• pp.53-60
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• 2005

Recently, sub-micron CMOS technologies have taken the place of III-V materials in a number of areas in integrated circuit designs, in particular even for the applications of gjgabit optical communication applications due to its low cost, high integration level, low power dissipation, and short turn-around time characteristics. In this paper, a four-channel transimpedance amplifier (TIA) array is realized in a standard 0.35mm CMOS technology Each channel includes an optical PIN photodiode and a TIA incorporating the fully differential regulated cascode (RGC) input configuration to achieve effectively enhanced transconductance(gm) and also exploiting the inductive peaking technique to extend the bandwidth. Post-layout simulations show that each TIA demonstrates the mid-band transimpedance gain of 59.3dBW, the -3dB bandwidth of 2.45GHz for 0.5pF photodiode capacitance, and the average noise current spectral density of 18.4pA/sqrt(Hz). The TIA array dissipates 92mw p in total from a single 3.3V supply The four-channel RGC TIA array is suitable for low-power, high-speed optical interconnect applications.

• The Korean Journal of Pain
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• v.1 no.2
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• pp.154-163
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• 1988

In 1983, Sten H$\ddot{a}$kanson first reported the clinical safety and efficacy of retrogasserian glycerol injection as a treatment of typical trigeminal neuralgia in 96 of 100 patients during a follow-up period of 1~6 years. Since September 1987, we have injected sterile pure glycerol into the trigeminal cistern using an anterior percutaneous approach via the foramen ovale (H$\ddot{a}$rtel route) for treatment of tic douloureux in 12 patients who were suffering from attacks pain of following discontinuation of carbamazepine. The results were as follows; 1) Eight patients were completely free from pain attacks with a single dose of glycerol (0.4 ml). The remaining four patients needed a second dose (0.4 ml) several days later following the single dose. The degree of patient's subjective satisfaction by those injections was very good in 11 and fair in one. 2) During the follow-up period (1~13 months), persistent sensory deficit as determined by the pin prick test, appeared to be mild in 10 and moderate in one patient. There was no sensory deficit in one patient. further attacks of pain from those injections were still noted. 3) As a transient complication, there was headache in all patient, facial hematoma in 4, nausea and vomiting in two each, and vertigo and herpes simplex in one each. In conclusion, we confirmed that the above glycerol injections into the trigeminal cistern were clinically very effective as a treatment of tic douloureux even though the follow-up period was short.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1277-1279
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• 1994

In the structure of ZnO/nip-SiC: H/metal substrate amorphous silicon (a-Si:H) solar cells, the effects of inserting a rear textured ZnO in the p-SiC:H/metal interface and a graded bandgap buffer layer in the i/p-SiC:H have been analysed by computer simulation. The incident light was taken to have an intensity of $100mW/cm^2$(AM-1). The thickness of the a-Si:H n, ${\delta}$-doped a-SiC:H p, and buffer layers was assumed to be $200{\AA},\;66{\AA}$, and $80{\AA}$, respectively. The scattering coefficients of the front and back ZnO were taken to be 0.2 and 0.7, respectively. Inserting the rear buffer layer significantly increases the open circuit voltage($V_{oc}$) due to reduction of the i/p interface recombination rate. The use of textured ZnO markedly improves collection efficiency in the long wavelengths( above ${\sim}550nm$ ) by back scattering and light confinement effects, resulting in dramatic enhancement of the short circuit current density($J_{sc}$). By using the rear buffer and textured ZnO, the i-layer thickness of the ceil for obtaining the maximum efficiency becomes thinner(${\sim}2500{\AA}$). From these results, it is concluded that the use of textured ZnO and buffer layer at the backside of the ceil is very effective for enhancing the conversion efficiency and reducing the degradation of a-Si:H pin-type solar cells.

• Journal of the Korean Arthroscopy Society
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• v.13 no.2
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• pp.174-178
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• 2009

Purpose: We introduce arthroscopic assisted core decompression for humeral head osteonecrosis. Operative technique: After diagnostic shoulder arthroscopy is performed using posterior and anterior portal, we make a 2 cm lateral skin incision approximately 3 cm distal to 1/3 of lateral margin of the acromion and place short gray cannula to prevent adjacent soft tissue injury when insert guide pin. Under C-arm fluoroscopic and arthroscopic guidance, 3 to 4 guide pins are inserted toward the necrotic area. Then we perform drilling using 7.0 mm reamer. Conclusion: We believe this technique is a less invasive approach and avoids the complications comparing to deltopectoral approach. Arthroscopic assisted core decompression is an effective procedure in management of early stage of the humeral head osteonecoris.

• Nuclear Engineering and Technology
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• v.53 no.1
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• pp.44-60
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• 2021

In this paper, we validate the decay heat calculation capability via a two-step method to analyze spent nuclear fuel (SNF) discharged from pressurized water reactors (PWRs). The calculation method is implemented with a lattice code STREAM and a nodal diffusion code RAST-K. One of the features of this method is the direct consideration of three-dimensional (3D) core simulation conditions with the advantage of a short simulation time. Other features include the prediction of the isotope inventory by Lagrange non-linear interpolation and the use of power history correction factors. The validation is performed with 58 decay heat measurements of 48 fuel assemblies (FAs) discharged from five PWRs operated in Sweden and the United States. These realistic benchmarks cover the discharge burnup range up to 51 GWd/MTU, 23.2 years of cooling time, and spanning an initial uranium enrichment range of 2.100-4.005 wt percent. The SNF analysis capability of STREAM is also employed in the code-to-code comparison. Compared to the measurements, the validation results of the FA calculation with RAST-K are within ±4%, and the pin-wise results are within ±4.3%. This paper successfully demonstrates that the developed decay heat calculation method can perform SNF back-end cycle analyses.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.6 no.9
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• pp.81-90
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• 2016

Recently drones have become popular enough to be one of the hobby. The drone refers to an unmanned aerial vehicle which can fly and be steered by a radio wave without a pilot and it has a airplane or helicopter shape. The drone was first started to be used from military purpose, but its usage has been expanded to the private such as construction site, crop-dusting, field discovery, freight shipping and drones to prevent cheating. However the drone that we can see often in the market is expansive, hard to be repaired when it broken down and has a discomfort of the short flight time. In this paper, to solve an uncomfortable talk on the cheap 8-bits microcontrollers ATmega128 Using drone for implementation. Axes gyroscope and accelerometers mcu between posture an attitude control, communications through drone control, pid. Receiver input them into transmitter signals of movements to control drone c the programming was implemented in on the basis of language. drone using ATmega128 microcontroller is possible hovering, By utilizing a pin that are not required for control it can be used as a drone for a variety of uses.

• Journal of Korean Foot and Ankle Society
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• v.11 no.2
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• pp.160-165
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• 2007

Purpose: Good results using minimal invasive hallux valgus surgery has been reported recently. We evaluate the usefulness of linear distal metatarsal osteotomy with minimal skin incision in mild and moderate hallux valgus deformity. Materials and Methods: Twenty-eight patients (thirty-one cases) who had mild to moderate hallux valgus deformity and underwent linear distal metatarsal osteotomy using minimal skin incision were evaluated between February 2005 and February 2006. Hallux-metatarsophalangeal-interphalangeal scale of AOFAS (American Orthopaedic Foot and Ankle Society) score was used as clinical evaluation. Preoperative, postoperative, after pin removal, and final follow up plain radiographs were used as radiologic evaluation. Results: Twenty-six cases (83%) among thirty-one cases showed more than average satisfaction, Average AOFAS score were improved from 63.2 points (range 45-74 points) to 86.4 points (range 67-93 points). Preoperative radiologic index of IMA $14.0^{\circ}$ (range $10-18^{\circ}$), HVA $30.2^{\circ}$ (range $19-39^{\circ}$), DMAA $13.8^{\circ}$ (range $5-23^{\circ}$) were improved postoperatively as IMA $8.3^{\circ}$ (range $5-10^{\circ}$), HVA $10.5^{\circ}$ (range $2-20^{\circ}$), DMAA $7.2^{\circ}$ (range $0-14^{\circ}$) correctively. Mean operative time was 15.5 minutes (range 11-18 minutes) and mean operative time was 5.6 days (range 2-8 days). Conclusion: Despite small skin incision and short operative time and admission period, linear distal metatarsal osteotomy with minimal skin incision showed similar results with conventional distal metatarsal osteotomy. Thus, it was thought to be useful operation in mild and moderate hallux valgus deformity.

• Clinics in Shoulder and Elbow
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• v.14 no.1
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• pp.94-98
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• 2011

Purpose: We present a case of anterior glenoid rim comminuted fracture that was treated with arthroscopic reduction and an AO headless compression screw (HCS) fixation. Materials and Methods: A 31-year old man complained of left shoulder pain after falling down on stairs. The anterior glenoid comminuted fragments were arthroscopically reduced. Fixation with an AO HCS was done after placement of 1.1 mm Kirschner wire as a guide pin through a standard cannulated anterosuperior portal. Results: Twelve months after the operation, union of the fracture was achieved and the range of motion was fully recovered. He did not complain of any discomfort during his activities of daily living. Conclusion: An AO HCS had various screw sizes and this was good for fixation of a small glenoid fracture and a long drill bit and screw driver were useful for fixation of deep seated glenoid fracture. A short guide wire could be replaced by a 1.1 mm K-wire. An AO HCS was useful for fixation of an anterior glenoid rim comminuted fracture.

• 한국노년학
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• v.34 no.2
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• pp.247-258
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• 2014

The aim of this study was to investigate the influence of resilience and depression on suicidal ideation in elderly. The survey was conducted by 335 subjects (aged 65 to 70 years old; both gender) living in Daegu and Gyeongbuk district. Data were collected through interview-based questionnaires which were constructed to include the general characteristics(8 items), suicidal ideation(19 items), depression(15 items), and resilience(27 items). Collected data were analyzed by frequency, t-test, one-way ANOVA, and regression analysis. The present results showed that the main general factors affecting the resilience of elderly were age, the type of dwelling, pin money, and health. The influencing factors on suicidal ideation were health status, depression level, and the resilience in elderly. In particular, the suicidal ideation was more affected by self-regulation and affirmation of the subcategory in resilience. In conclusion, the resilience and depression is need to be considered as one of the main factors for decreasing the suicidal ideation in elderly.