• Journal of Korean Ophthalmic Optics Society
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• v.13 no.4
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• pp.1-8
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• 2008

Purpose: We investigated opticians' and the public (including optometry students) opinions about university/college affiliated optical shops. Methods: Opinions about the university/college affiliated optical shops, their positive or negative effects, services range, how to obtain their operation cost, and so on were asked to 50 opticians and 51 public people (including optometry students) by a questionnaire survey, being statistically analysed. Results: Most respondents answered positive opinions about the university/college affiliated optical shops, anticipating better eye test ability of Koean optometry graduates through improved clinical education. Conclusions: The university/college affiliated optical shops are expected to contribute to clinical education and research in Korea. Legal revisions and efforts of each university/college are required.

• Journal of KIISE:Computer Systems and Theory
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• v.30 no.12
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• pp.736-748
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• 2003

Dynamic voltage scaling(DVS), which adjusts the clock speed and supply voltage dynamically, is an effective technique in reducing the energy consumption of embedded real-time systems. The energy efficiency of a DVS algorithm largely depends on the performance of the slack estimation method used in it. In this paper, we propose novel DVS algorithms for periodic hard real-time tasks based on an improved slack estimation algorithm. Unlike the existing techniques, the proposed method can be applied to most priority-driven scheduling policies. Especially, we apply the proposed slack estimation method to EDF and RM scheduling policies. The experimental results show that the DVS algorithms using the proposed slack estimation method reduce the energy consumption by 20∼40 % over the existing DVS algorithms.

• Journal of Astronomy and Space Sciences
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• v.14 no.2
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• pp.297-311
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• 1997

To understand the mass-independent isotopic fractionation effects, thermal decomposition of ozone was performed. Initial oxygen gas was converted to ozone completely. Then, the ozone was decomposed to oxygen at various temperatures ($30~150^{\circ}C$). Isotopic compositions of product oxygen and residual ozone were measured using a stable isotope mass spectrometer. The experimental results were compared with the studies which were performed at the similar conditions. From the raw experimental data, the functions of the instantaneous fractionation factors were calculated by the least square fit. The results clearly showed the temperature dependence. They also showed the pressure dependence and the surface effect. This study may play an important role in the study of ozone decomposition mechanism. It can be applied to explain the mass-independent isotopic pattern found in stratospheric ozone and in meteorites.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2001.04a
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• pp.79-79
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• 2001

백판지는 포장용기로 사용되기 때문에 인쇄적성 이외에 다양한 후가공적성이 요구 된다. V Varnish Coating도 이러한 후가공적성 중의 하나로서 국내 인쇄소에서는 기계 코팅으로 불리 우며, 목적은 표면에 고분자수지 피막을 입힘으로써 인쇄물의 광택을 높여서 상품가치를 높이고 수운침투와 같은 외부환경의 변화로부터 상품을 안전하게 보관하기 위함이다. arnish C Coating은 인쇄기의 마지막 Unit에서 인쇄와 동일한 방식으로 진행되는데, 코팅액의 배합은 인쇄소와 인쇄물에 따라 상이하다. 본 연구는 Varnish Coating(OI하 기계코팅) 광택향상을 통 한 품질개선 목적으로 수행되었다. 기계 코팅의 특 성 을 파 악 하 기 위 해 서 Gas Chromatography / Mass Spectrometer와 FT -IR Sp e ectrometer를 사용하여 성문운석을 실시해본 결과 코팅액으로 사용되는 광택바니스는 아크 랄과 페놀수지를 툴루엔 계열의 용매에 녹인 용액이고, 흐$\mid$석제로 쓰이는 인쇄바니스는 스티 렌수지를 동일한 용매에 녹인 용액으로 조사되었다. 기계코팅광택 저하현상의 원인파악을 위해서 도공층의 공극구조를 Mercury Porosimeter를 이용하여 파악한 결과 기공의 부피가 상 대적으로 크게 나타났다. 위의 결과를 토대로 기계코팅광택 저하는 코팅액이 과도한 기공부피를 갖는 도공층 내부 로 대부분 홉수되고 표면에 적은 양만이 잔류하기 때문으로 판단하고 해결방안은 도공층의 기공부피를 줄이는 쪽으로 정하였다. Mayor Coater와 QC를 이용하여 Coating Color Formula t tion 번경실힘을 진행하여 도공지 물성을 분석하였다. 그 결과 Double Coating의 Top Color에 서 강력한 상호작용을 하는 Protein과 콜레이를 감량 하고 경질탄산칼숨을 배제하여 기공의 부피를 줄인 경우 기계코팅광택 향상효과가 두드러지게 나타났다. 이러한 Lab 실험을 바탕으로 결정된 Color Formulation에 대한 현장실험을 진행하였고 Lab 평가 및 실인쇄 평가 결과 원하는 수준의 기계코팅광택 향상을 얻을 수 있었다. 몇 차례의 현장실험과 Long-Run Test한 제품들에 대한 물성을 문석한 결과 기계코팅굉택은 인쇄 광택과 같은 경향을 나타냈으며 실협실적으로 간단하게 측정되는 물성 중에서 Air Permeability와 강한 음의 상관관계롤 보였다.

• Economic and Environmental Geology
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• v.4 no.3
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• pp.113-119
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• 1971

The Daeheung Dolomite Mine, which is about 6km south of Danyang, Chungcheongbugdo, is coincided with almost central portion of the Danyang quardrangle scaled in 1 : 50,000. The purpose of this report is to prepare a information for the economic evaluation on the mine. Geology of the region is composed of worm-eaten limestone, crystalline limestone, crystalline dolomite rock, sandstone and shale from bottom, those are applicable to socalled Dumugol and Maggol formation of Ordovician, and batholithic biotite granite is intruded the west-side of the ditto sedimentary rocks. The dolomite bed, emplaced in bottom of the upper limestone formation, so-called Maggol formation, is about 270m in thickness, and dips $30^{\circ}{\sim}50^{\circ}$ northwest. The facies of the dolomite rock contained many brucite crystals is not only coarse-grained crystalline, but also micro crystalline in contact metasomatic parts. 25 samples were taken from the two series, A and B, in the nearly crossed direction to the strike of the dolomite bed as shown in the geological map. They were chemically analysed on the components of MgO, CaO, and $SiO_2$ as shown in Table 2. The estimate ore reserves total some 107,200,000 metric tons above the 320m level with the following average contents: MgO 21.80%, CaO 29.27% and $SiO_2$ 0.64%. It is caused by brucite minerals that MaO content in the dolomite rock is higher than pure dolomite (21.7%). The dolomite ore is possible in use for magnesian fertilizer, magnesian cement and refractory material, especially the microcrystalline dolomite ore is useful for a refractory material in furnaces of iron industries.

• Archives of design research
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• v.15 no.1
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• pp.327-338
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• 2002

Nowadays, in accordance with our information-oriented society, industries based on digital Technology have been quickly developing all over the world. This industryhas been playing an important role in improving the quality of peoples'lives so far and will continue to do so, both culturally and socially through industrial and economic aspects. Particularly, the electronic game, on e of the representatives, is providing an intensive value-added segment to the entertainment industry. Games are deeply rooted in people's lives and have a big influence on the industry, society and culture, even our life styles. Consequently, this study is investigating change the electronic game by the times and analyzing the game entity. It is based on the research and analysis of the transition of electronic games in each era. From now on, we will look forward, using previous material in an attempt to forecast the right direction of electronic game design in the future.

• Journal of Digital Convergence
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• v.13 no.3
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• pp.209-214
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• 2015

Social network services such as Facebook and Flickr is a very useful service that was the foundation of the Internet. If a state in which the Internet is connected, music, photos, and us to be able to share it freely post such as documents. However, even when the digital information posted in such social network services the user has died, and have been published, it is also used for people who do not intend the bad purposes some problems can occur. Facebook is trying to apply the findings Jed R. Brubaker of UC Irvine University in order to solve this problem. However, in Korea, such efforts, not much appears for now. Therefore, we proposed a method that can be managed by delegated Facebook, safely a Delegator digital information posted on social networking services such as Flickr. Our proposed system, as compared with Jed R. Brubaker and Jeong-Kyung Moon is executed previous studies, we studied a method proposed by the appropriate compensates points shortage is passed through the future research. And I consider to have been proposed a method to safely use posted digital assets in a social network service.

• Corrosion Science and Technology
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• v.11 no.6
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• pp.275-279
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• 2012

Ni-W alloy deposits have lately attracted the interest as an alternative surface treatment method for hard chromium electrodeposits because of higher wear resistance, hardness at high temperature, and corrosion resistance. This study deals with influences of process variables, such as electodeposition current density, plating temperature and pH, on the internal stress of Ni-W nanocrystalline deposits. The internal stress was increased with increasing the applied current density. With increasing applied current density, the grain size of the deposit decreases and concentration of hydrogen in the deposit increases. The subsequent release of the hydrogen results in shrinkage of the deposit and the introduction of tensile stress in the deposit. Consequently, for layers deposited at high current density, cracking occurs readily owing to high tensile stress value. By increasing the temperature of the electrodeposition from $60^{\circ}C$ to $80^{\circ}C$, the internal stress was decreased. It seems that an increase in the number of active ions overcoming the activation energy at elevated temperature caused a decline in the concentration polarization and surface diffusion. It decreased the level of hydrogen absorption due to the lessened hydrogen evolution reaction. Therefore, the lower level of hydrogen absorption degenerated the hydride on the surface of the electrode, resulting in the reduction of the internal stress of the deposits. By increasing the pH of the electrodeposition from 5.6 to 6.8, the internal stress in the deposits were slightly decreased. It is considered that the decrease in internal stess of deposits was due to supply of W complex compound in cathode surface, and hydrogen ion resulted from decrease of activity.

• The Korean Journal of Pain
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• v.2 no.1
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• pp.21-25
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• 1989

For the simple operations of the perineal region, caudal, epidural and saddle blocks of analgesia are preferable anesthesia techniques in men. But, if the operations shoud be delayed or the physicians are willing to observe and manipulate the patients for a couple of days, as in the ureteral stone manipulation, continuous epidural analgesia will be a reliable method. The authors have observed 36 male patients of ureteral calculi with continuous lumbar epidural analgesia for the purpose of elimination of an undesirable pain sensation which was associated with the transurethral cystoscopic manipulation. The results were as follows: 1) In most cases, the anesthetics used were 1% lidocaine 20 ml through the $L_{3-4}$ and $L_{4-5}$ interspace with 4~6cm of catheter tip advancement mainly to cephalad. 2) There was no motor weakness or paralysis in the lower extremities except some numbness and paresthesia on the perineal area. 3) Besides the various minor complications, there were no problems in respiration with small doses of morphine extradurally. 4) Among them, four cases of ureteral calculi dropped into the bladder spontaneously due to the epidural technique during transportation of the patients from the pain clinic to the urology out-clinic. One case of calculi was dropped by the aid of instrumentation at the ward, and twelve cases of calculi were removed directly by Dormia stone basket in the scopic room. For the remaining patients, we deduced that their calculi was be evacuated out because there were no complaints were notified after discharge.

• The Korean Journal of Pain
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• v.22 no.2
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• pp.167-170
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• 2009

Pharmacological management is the first choice for treatment of the trigeminal neuralgia patients; however, if this mode of treatment fails a minimally invasive procedure should be performed. One of the most commonly used procedures is conventional radiofrequency lesioning of the Gasserian ganglion. Despite its popularity and success rate, this technique has disadvantages such as diminished corneal reflex, masseter weakness, numbness and anesthesia dolorosa. As a result, many studies have been conducted in an attempt to find a better method of treating trigeminal neuralgia. We report here a case of a trigeminal neuralgia patient that was treated with pulsed radiofrequency lesioning of the supraorbital and supratrochlear nerve due to pain in the frontal head that was refractory to the pharmacological treatments. Following the procedure, the Visual Analogue Scale score for pain decreased to 1-2/10 and the pain relief persisted for 7 months. These results indicate that pulsed radiofrequency treatment of the peripheral nerve may be useful for trigeminal neuralgia patients that do not respond to pharmacological treatments.