• Journal of Korean Society of Steel Construction
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• v.22 no.5
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• pp.477-485
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• 2010

Various monitoring sensors are used to predict and detect structural damage. Smart sensors, such as glass-fiber sensors, PZT, and MEMS, among others, have replaced traditional sensors. They are now being used in many areas. This study aims to predict the damage by measuring the PZT voltage attached on the specimen by the applied impact load. In the experiment to detect damages in beam connection, simple $H-400{\times}200{\times}8{\times}13$ beams were spliced with bolts. The results of FFT between PZT sensor and accelrometer were compared to measure the sensitivity of the PZT sensor. The damage to the beam was presumed by loosening the bolt, and then the damage measurement was accompanied. Secondly, a steel $PL600{\times}65{\times}5.8$ plate beam was fabricated for the purpose of experimenting on damage measurement. Impact loading test on three different locations was carried out. Damage width varied between 6~42mm on both sides by cutting, using a steel saw. The ratio of frequencies before and after the damage was computed to quantify the damage level by using FFT, and the change in mode pattern with the increased damage was investigated to measure the damage.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.139.2-139.2
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• 2013

6" Multi-crystal Silicon wafer has etched suing a remote - type RF Dielectric barrier discharge (RF DBD) at atmospheric pressure. DBD source is composed of Al electrode and coated Al2O3 dielectric as function of Ar/NF3 gas combination and input power used 13.56 MHz power supply. Ar gas flow rate is changed from 2 to 10 Slm, and NF3 flow rate is changed from 0.2~1 slm. At the result, NF3 flow rate Si etching rate also increase whit the increasing of NF3 flow rate But at 2 slm etching rate was decrease. In this experience, Max etching rate is 2.3 ${\mu}m/min$ when the scan time is 45 sec.

• Journal of the Korean Applied Science and Technology
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• v.40 no.6
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• pp.1289-1297
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• 2023

In this study, NF Complex of 0%, 0.5%, 2.5%, 12.5%, and 100% was prepared by complexing and extracting Indian gooseberry, Rosa multiflora Thunberg roots, and saw palmetto fruit in a ratio of 5:1:1. The manufactured NF Complex was applied to bleached sample hair and then compared and analyzed with damaged hair. To confirm the improvement effect, tensile strength, gloss, absorbance, and brightness were measured. As a result of the measurement, the tensile strength increased. The gloss content decreased by 100%, but the remaining content increased. The change in absorbance was minimal. There was also a change in brightness, but it was minimal. It was confirmed that there is a significant difference in the average value of NF Complex, and it is judged necessary to study various ratios in the future.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.43 no.5
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• pp.318-323
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• 2017

Objectives: Mandibular angle reduction or reduction genioplasty is a routine well-known facial contouring surgery that reduces the width of the lower face resulting in an oval shaped face. During the intraoral resection of the mandibular angle or chin using an oscillating saw, unexpected peripheral nerve damage including inferior alveolar nerve (IAN) damage could occur. This study analyzed cases of damaged IANs during facial contouring surgery, and asked what the basic standard of care in these medical litigation-involved cases should be. Materials and Methods: We retrospectively reviewed a total of 28 patients with IAN damage after mandibular contouring from August 2008 to July 2015. Most of the patients did not have an antipathy to medical staff because they wanted their faces to be ovoid shaped. We summarized three representative cases according to each patient's perceptions and different operation procedures under the approvement by the Institutional Review Board of Seoul National University. Results: Most of the patients did not want to receive any further operations not due to fear of an operation but because of the changes in their facial appearance. Thus, their fear may be due to a desire for a better perfect outcome, and to avoid unsolicited patient complaints related litigation. Conclusion: This article analyzed representative IAN cutting cases that occurred during mandibular contouring esthetic surgery and evaluated a questionnaire on the standard of care for the desired patient outcomes and the specialized surgeon's position with respect to legal liability.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.91-91
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• 2009

태양전지의 전극소성 시 알루미늄 후면 전극이 실리콘으로 확산되어 후면전계(Back Surface Field)를 형성한다. 후면 패시베이션층은 후면반사율을 높여 내부광흡수경로를 늘리고 후면재결합속도를 감소시킨다. 본 논문은 후면 패시베이션층이 알루미늄 후면전계 형성에 미치는 영향 및 온도에 따른 변화를 관찰하였다. 절삭손상(Saw damage)이 제거된 실리콘 기판의 후면에 패시베이션층이 없는 것과 후면 패시베이션층으로 사용되는 실리콘 산화막을 형성시킨 시편을 제작하였다. 알루미늄 후면전극을 스크린 인쇄 후 소성온도를 달리하여 실리콘과 알루미늄과의 반응을 비교하였다. 주사전자현미경(SEM)을 사용하여 시편의 단면사진으로부터 소성온도에 따른 실리콘과 알루미늄간의 반응 여부를 관찰하였고, 열분석을 통해 반응 온도를 조사하였다. 패시베이션층이 없는 경우에는 약 $600^{\circ}C$부터 실리콘과 알루미늄간의 반응이 시작되었고, 패시베이션층이 있는 경우에는 약 $700^{\circ}C$부터 반응이 시작되는 결과를 얻었다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.977-980
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• 2004

본 논문에서는 저가 고효율 태양전지를 제작하기 위하여 p형 다결정 실리콘 기판을 사용하여 수산화 칼륨(KOH)이 포함된 용액에 Saw damage 과정 후 불산이 함유된 용액에 전기화학적 양극산화 과정으로 실리콘 웨이퍼 표면에 요철을 형성하여 다공성 실리콘을 형성 하였다. 본 논문은 전기화학적 에칭방법으로 기존의 진공장비로 제작된 반사방지막의 반사율만큼 감소된 다공성 실리콘 반사방지막을 형성하였다. 전자빔 증착기(e-beam evaporator)로 단층으로 형성된 $TiO_2$의 반사방지막은 400-1000 nm의 파장 범위에서 4.1 %의 평균 반사율을 가졌으며, 양극산화과정으로 형성된 다공성 실리콘은 400-1000 nm의 파장의 범위에서 4.4 %의 평균 반사율을 가졌다. 본 연구는 태양전지의 반사방지막 형성을 기존의 제작 방법보다 간단하고 저렴한 방법으로 접근하여 태양전지의 변환효율을 상승하는데 목적을 두었다.

• International Journal of Highway Engineering
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• v.19 no.3
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• pp.11-18
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• 2017

PURPOSES : This study investigates the effect on concrete pavement accordance with the curing methods in cool weather and supports the best method in the field. METHODS : Two field tests evaluated the curing methods of concrete pavement in cool weather. Firstly, five curing methods were tested, including normal curing compound, black curing compound, bubble sheet, curing mat, and curing mat covered with vinyl. Concrete maturity was compared from temperature data. Secondly, normal curing compound and curing mat with vinyl, which showed the best performance, were compared in terms of maturity and join condition index. RESULTS:From the field tests, it is an evident that curing mat with vinyl accelerated the concrete strength. Therefore, it is possible to conduct saw-cut works in cool weather, which minimizes damage on concrete at joint. CONCLUSIONS : For concrete pavement in cool weather, using curing mat with vinyl as the curing method could overcome the strength delay. Therefore, strength and durability problems on concrete at joint due to cool weather would be fewer in the future.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.28 no.1
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• pp.53-60
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• 2018

Cryptographic algorithms are being standardized globally, and the security of cryptographic algorithms has been well proven. However, there is a need for an improved verification method to verify that the existing verification method is correctly implemented according to the standard, because there is a weakness in implementation and it can cause serious damage. Therefore, in this paper, we selected ARIA and LEA to be verified among 128-bit or more block cipher modules performed by the National Intelligence Service, and propose a method to verify whether it is implemented correctly using Cryptol for high-assurance cryptographic module.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.299.2-299.2
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• 2013

We investigated the potassium remaining on a crystalline silicon solar cell after potassium hydroxide (KOH) etching and its effect on the lifetime of the solar cell. KOH etching is generally used to remove the saw damage caused by cutting a Si ingot; it can also be used to etch the rear side of a textured crystalline silicon solar cell before atomic layer-deposited Al2O3 growth. However, the potassium remaining after KOH etching is known to be detrimental to the efficiency of Si solar cells. In this study, we etched a crystalline silicon solar cell in three ways in order to determine the effect of the potassium remnant on the efficiency of Si solar cells. After KOH etching, KOH and tetramethylammonium hydroxide (TMAH) were used to etch the rear side of a crystalline silicon solar cell. To passivate the rear side, an Al2O3 layer was deposited by atomic layer deposition (ALD). After ALD Al2O3 growth on the KOH-etched Si surface, we measured the lifetime of the solar cell by quasi steady-state photoconductance (QSSPC, Sinton WCT-120) to analyze how effectively the Al2O3 layer passivated the interface of the Al2O3 layer and the Si surface. Secondary ion mass spectroscopy (SIMS) was also used to measure how much potassium remained on the surface of the Si wafer and at the interface of the Al2O3 layer and the Si surface after KOH etching and wet cleaning.

• Korean Security Journal
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• no.41
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• pp.37-66
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• 2014

In recent years, with the development of computers and electronics, electronics and communication technology in a growing and each part is dependent on the cross-referencing makes all electronic equipment is obsolete due to direct or indirect damage EMP. Korea and the impending standoff North Korea has a considerable level of technologies related to the EMP, EMP weapons you already have or in a few years, the development of EMP weapons will complete. North Korea launched a long-range missile and conducted a nuclear test on several occasions immediately after, when I saw the high-altitude nuclear blackmail has been strengthening the outright offensive nuclear EMP attacks at any time and practical significance for the EMP will need offensive skills would improve. At this point you can predict the damage situation of Korea's security reality that satisfy the need, more than anything else to build a protective system of the EMP. The scale of the damage that unforeseen but significant military damage and socio-economic damage and fatalities when I looked into the situation which started out as a satellite communications systems and equipment to attack military and security systems and transportation, finance, national emergency system, such as the damage elsewhere. In General, there is no direct casualties reported, but EMP medical devices that rely on lethal damage to people who can show up. In addition, the State power system failure due to a power supply interruption would not have thought the damage would bring State highly dependent on domestic power generation of nuclear plants is a serious nuclear power plant accident in the event of a blackout phenomenon can lead to the plant's internal problems should see a forecast. First of all, a special expert Committee of the EMP, the demand for protective facilities and equipment and conduct an investigation, he takes fits into your budget is under strict criteria by configuring the contractors should be sifting through. He then created the Agency for verification of performance EMP protection after you have verified the performance of maintenance, maintenance, safety and security management, design and construction company organized and systematic process Guard facilities or secret communications equipment and perfect for the EMP, such as protective equipment maneuver system should take.