• 제목/요약/키워드: Defects

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고에너지 P이온 주입한 실리콘에 형성된 격자 결함에 관한 고분해능 투과전자현미경 연구 (A High-Resolution Transmission Electron Microscopy Study on the Lattice Defects Formed in the High Energy P Ion Implanted Silicon)

  • 장기완;이정용;조남훈;노재상
    • 한국세라믹학회지
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    • 제32권12호
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    • pp.1377-1382
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    • 1995
  • A high-resolution transmission electron microscopy study on the lattice defects formed in the high energy P ion implanted silicon was carried out on an atomic level. Results show that Lomer dislocations, 60$^{\circ}$perfect dislocations, 60$^{\circ}$ dislocation dipole and extrinsic stacking fault formed in the near Rp of as-implanted specimen. In the annelaed specimens, interstitial Frank loops, 60$^{\circ}$perfect disolations, 60$^{\circ}$dislocation dipoles, stacking faults, precipitates, perfect dislocation loops and <112> rodlike defects existed exclusively near in the Rp with various annealing temperature and time. From these results, it is concluded that extended secondary defects as well as the point defect clusters could be formed without annealing. Even at low temperature annealing such as 55$0^{\circ}C$, small interstitial Frank loops could be formed and precipitates were also formed by $700^{\circ}C$ annealing. The defect band annealed at 100$0^{\circ}C$ for 1 hr could be divided into two regions depending on the distribution of the secondary defects.

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CISG상 권리부적합에 대한 매수인의 구제권에 관한 연구 (A Study on the Buyer's Remedies in respect of Defects in Title under CISG)

  • 민주희
    • 무역상무연구
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    • 제61권
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    • pp.3-28
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    • 2014
  • This study describes the buyer's remedies regarding defects in title under CISG. Although CISG stipulates the seller's liability for the delivery of conforming goods physically at Art. 35 and legally at Art. 41 and Art. 42 respectively, the buyer's remedies are not distinguished between non-conformity governed by Art. 35 and defects in title governed by Art. 41 and Art. 42. If the seller does not fulfill his obligation under Art. 41 and Art. 42 to deliver goods which are free from third party claims, the buyer should pay attention to which remedies are available under CISG. Under CISG, for defects in title in the delivered goods, the buyer is entitled to require performance in Art. 46 (1) unless he has resorted to a remedy which is inconsistent with this requirement, to declare the contract avoided by strictly limiting the situation in which the failure by the seller to perform his obligation amounts to a fundamental breach of contract in Art. 49, to claim damages in Art. 74, and to suspend the performance of his obligation where it becomes apparent that the seller will not perform a substantial part of his obligation in Art. 71 (1). Unlike Art. 35 non-conformity, the buyer may not require delivery of substitute goods under Art. 46 (2), claim repair under Art. 46 (3), and declare price reduction for title defects under Art. 50.

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아파트단지 조경수목의 식재하자에 관한 연구 (Defects of Planting in Landscape Plants in Apartment Complex)

  • 임원현;김용수
    • 한국조경학회지
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    • 제29권2호
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    • pp.61-67
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    • 2001
  • The purpose of this thesis was to provide the basic data for landscape architecture of apartment constructions and to minimize the users´ and builder´ loss in terms of finance and landscape due to defects in planting. After a review of literature related to defects of planting work, the researcher investigated the defects in planting of landscape plants on the basis of data from the drawing and defect-repair construction of 50 civil apartment complexes in Daegu and Kyongbook are from 1994 to 1998. The defect-ratio was analysed in terms of the species, shapes, and sizes of trees. It provides matters for consideration in terms of the design of the landscape planting on the apartment unit. It also provided the future directions for landscape architecture in apartment constructions with regard to the selection of the planting trees, etc., given statistics on defect occurrence. The causes of defect of the landscape planting trees were not studied accurately in this study due to the board range of researched area, the differences of the planting ground environment, the management ability, and the parameters of judging planting defects. It is recommended that those areas should be researched in the future.

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Demerit-DEWMA 관리도 (A Study of Demerit-DEWMA Control Chart)

  • 강해운;백재원;강창욱
    • 산업경영시스템학회지
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    • 제33권2호
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    • pp.9-17
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    • 2010
  • Complex products may present more than one type of defects and these defects are not always of equal severity. These defects are classified according to their seriousness and effect on product quality and performance. So, demerit systems are very effective systems to monitor the different types of defects. Recently, Kang et al.(2009) proposed the revised Demerit-CUSUM for the evaluation of the Demerit-CUSUM control chart performance exactly. In this paper, we present an advanced Demerit control chart using the double EWMA technique. The double EWMA technique is very efficient and strong method for process control where defects and nonconformities occur with various defect types. Moreover, we compare exact performance of Demerit-CUSUM, Demerit-EWMA and Demerit-DEWMA control chart according to changing sample size or mean shifts magnitude. By the result, we confirm that the performance of Demerit-DEWMA control chart is more than the performance of the Demerit-CUSUM and Demerit-EWMA control chart.

상악동 후벽의 실험적 골결손부에 관한 방사선학적 연구 (A RADIOGRAPHIC STUDY OF EXPERIMENTALLY PRODUCED BONE DEFECTS IN THE POSTERIOR WALL OF THE MAXILLARY SINUS)

  • 최의환;박원길
    • 치과방사선
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    • 제26권2호
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    • pp.153-163
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    • 1996
  • The purpose of this study was to evaluate the ability of radiographs in detecting experimental bony defect in the posterior wall of the maxillary sinus. For this study, experimentally five skulls were used, the bony defects with a diameter of 5mm were created at different locations in the posterior wall of the right maxillary sinus and the bony defects of 10mm were created at different locations in the posterior wall of th maxillary sinus. Panoramic view, panoramic sinus view, water's view, and computed tomogram were taken and the results analyzed. The obtanined results were as follows: 1. The panoramic view was superior to the panoramic sinus view in detecting the bony defects in the posterior wall of the maxillary sinus. 2. Panoramic view, panoramic sinus view, and waters's view were limitation to the detection of the bony defects in the posterior wall of the maillary sinus. 3. All the bony defects in the posterior wall of the maxillary sinus were excellently visualized on the computed tomogram.

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광섬유 인선 공정에 의해 생성된 실리카 광섬유내 점결함 (Fiber Drawing Induced Defects in Silica Optical Fiber)

  • 안병길;이종원;김효태
    • 한국세라믹학회지
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    • 제40권11호
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    • pp.1102-1105
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    • 2003
  • 광섬유 인선공정에 의해 생성된 실리카 유리내 점결함을 조사하였다. 본 연구에서는 특히 OH기가 적은 실리카 광섬유내 광섬유 인선 공정이 유발하는 oxygen deficient center와 E' center를 중점적으로 조사하였다. 광섬유 인선공정에 의해 oxygen deficient center 와 E’ center가 생성되었다는 것을 광학적 흡수대와 electron spin resonance를 이용하여 밝힐 수 있었다. 실리카 광섬유모재에서 가느다란 광섬유로 변환하는 neck-down 부분에서 점결함의 변화를 조사하였다. 점결함은 neck-down 부분에서 생성되며, 중심부분 보다 가장자리 부분에서 더 많은 점결함이 생성되었음을 알 수 있었다.

HIP 처리에 의한 가스터빈 블레이드용 IN738LC 초합금의 내부결함 소멸 효과 (Effect of Hot Isostatic Pressing on Elimination of Internal Defects in IN738LC Superalloy for Gas Turbine Blade)

  • 박영규;김수형;김재철;이영찬;김두수;최철;김길무
    • 한국주조공학회지
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    • 제19권5호
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    • pp.427-432
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    • 1999
  • Most investment castings contain some porosities and microcavities. In this study, we investigated the elimination trends of various internal defects in IN738LC investment castings for industrial gas turbine blade by hot isostatic pressing. The results showed that cylindrical defects which are under $0.6mm{\Phi}{\times}7mm$ size are mostly eliminated and aspect ratio of defects is more sensitive factor than their cross section shape in removing these defects. Increasing hot isostatic pressure and holding time doesn't affect the elimination trend of cylindrical defects over $0.6mm{\Phi}{\times}7mm$ size because first step(plastic deformation) of HIP densification doesn't occur under these HIPping conditions.

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Reconstruction of Vacancy Defects in Graphene and Carbon Nanotube

  • Lee, Gun-Do;Yoon, Eui-Joon;Hwang, Nong-Moon;Wang, Cai-Zhuang;Ho, Kai-Ming
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2009년도 제38회 동계학술대회 초록집
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    • pp.340-340
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    • 2010
  • Various structures of vacancy defects in graphene layers and carbon nanotubes have been reported by high resolution transmission electron microscope (HR-TEM) and those arouse an interest of reconstruction processes of vacancy defects. In this talk, we present reconstruction processes of vacancy defects in a graphene and a carbon nanotube by tight-binding molecular dynamics (TBMD) simulations and by first principles total energy calculations. We found that a structure of a dislocation defect with two pentagon-heptagon (5-7) pairs in graphene becomes more stable than other structures when the number of vacancy units is ten and over. The simulation study of scanning tunneling microscopy reveals that the pentagon-heptagon pair defects perturb the wavefunction of electrons near Fermi level to produce the $\sqrt{3}\;{\times}\;\sqrt{3}$ superlattice pattern, which is in excellent agreement with experiment. It is also observed in our tight-binding molecular dynamics simulation that 5-7 pair defects play a very important role in vacancy reconstruction in a graphene layer and carbon nanotubes.

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CAD 데이터 및 엑스레이 CT이미지 비교를 통한 다이캐스팅 부품의 내부 결함 검사방법 (Internal Defects Inspection of Die-cast Parts via the Comparison of X-ray CT Image and CAD Data)

  • 홍경택;심재홍
    • 반도체디스플레이기술학회지
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    • 제17권1호
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    • pp.27-34
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    • 2018
  • Industrially, die-casting products are formed through casting, and so the methods to inspect the defects inside them are very restrictive. External inspection methods including visual inspection, sampling judgment, etc. enables researchers to inspect possible external defects, but x-ray inspection equipment has been generally used to inspect internal ones. Recently, they have been also applying three-dimensional internal inspections using CT equipment. However, they have their own limitations in applying to the use of industrial inspection due to limited detection size and long calculation time. To overcome the above problems, this paper has suggested a method to inspect internal defects by comparing the CAD data of the product to be inspected with the 3D data of the CT image. In this paper, we proposed a method for fast and accurate inspection in three dimensions by applying x-ray inspection to find internal defects in industrial parts such as aluminum die casting products. To show the effectiveness of the proposed method, a series of experiments have been carried out.

The evolution of radiation-induced point defects near symmetrical tilt Σ5 (310) <001> grain boundary in pure δ-plutonium: A molecular dynamics study

  • Wang, Yangzhong;Liu, Wenbo;Zhang, Jiahui;Yun, Di;Chen, Piheng
    • Nuclear Engineering and Technology
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    • 제53권5호
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    • pp.1587-1592
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    • 2021
  • The effects of the symmetrical tilt Σ5 (310) <001> grain boundary (GB) on the evolution of radiation-induced point defects in pure δ-plutonium (Pu) were studied by Molecular dynamics (MD) simulations. The evolution of radiation-induced point defects was obtained when primary knock-on atom (PKA) was respectively set as -15 Å and 15 Å far from the GB and the number of residual defects was obtained as the distance from PKA to GB was changed. According to the results, compared with vacancies, interstitial atoms were more easily absorbed by GB. In addition, the formation energy of point defects was also calculated. The results showed that there was almost no difference for the formation energy of vacancies in the all matrix. However, the formation energy of interstitial atoms close to the GB was lower than that in the other bulk regions.