• 제목/요약/키워드: Cutting State

검색결과 266건 처리시간 0.031초

A Comprehensive Review of Emerging Computational Methods for Gene Identification

  • Yu, Ning;Yu, Zeng;Li, Bing;Gu, Feng;Pan, Yi
    • Journal of Information Processing Systems
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    • 제12권1호
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    • pp.1-34
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    • 2016
  • Gene identification is at the center of genomic studies. Although the first phase of the Encyclopedia of DNA Elements (ENCODE) project has been claimed to be complete, the annotation of the functional elements is far from being so. Computational methods in gene identification continue to play important roles in this area and other relevant issues. So far, a lot of work has been performed on this area, and a plethora of computational methods and avenues have been developed. Many review papers have summarized these methods and other related work. However, most of them focus on the methodologies from a particular aspect or perspective. Different from these existing bodies of research, this paper aims to comprehensively summarize the mainstream computational methods in gene identification and tries to provide a short but concise technical reference for future studies. Moreover, this review sheds light on the emerging trends and cutting-edge techniques that are believed to be capable of leading the research on this field in the future.

드릴 가공된 구멍의 상태 검출에 관한 연구 (A Study on the Detection of the Drilled Hole State In Drilling)

  • 신형곤;김태영
    • 한국공작기계학회논문집
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    • 제12권3호
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    • pp.8-16
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    • 2003
  • Monitoring of the drill wear :md hole quality change is conducted during the drilling process. Cutting force measured by tool dynamometer is a evident feature estimating abnormal state of drilling. One major difficulty in using tool dynamometer is that the work-piece must be mounted on the dynamometer, and thus the machining process is disturbed and discontinuous. Acoustic transducer do not disturb the normal machining process and provide a relatively easy way to monitor a machining process for industrial application. for this advantage, AE signal is used to estimate the abnormal fate. In this study vision system is used to detect flank wear tendency and hole quality, there are many formal factors in hole quality decision circularity, cylindricity, straightness, and so of but these are difficult to measure in on-line monitoring. The movement of hole center and increasement of hole diameter is presented to determine hole quality. As the results of this experiment AE RMS signal and measurements by vision system are shorn the similar tendency as abnormal state of drilling.

드릴링시 가공이상상태의 온라인 검출에 관한 연구 (A Study on The On-line Detection of the Abnormal State in Drilling.)

  • 신형곤;박문수;김민호;김태영
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 춘계학술대회 논문집
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    • pp.1038-1042
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    • 2002
  • Monitoring of the drill wear and hole quality change is conducted during the drilling process. Cutting force measured by tool dynamometer is a evident feature estimating abnormal state of drilling. One major difficulty in using tool dynamometer is that the work piece must be mounted on the dynamometer, and thus the machining process is disturbed and discontinuous. Acoustic transducer do not disturb the normal machining process, and provide a relatively easy way to monitor a machining process for industrial application. For this advantage, AE signal is used to estimate the abnormal state. In this study vision system is used to detect flank wear tendency and hole quality, there are many formal factors in hole quality decision circularity, cylindricity, straightness, and so on, but these are difficult to measure in on-line monitoring. The movement of hole center and increasement of hole diameter is presented to determine hole quality As the results of this experiment, AE RMS signal and measurements by vision system are shown the similar tendency as abnormal state of drilling. And detection of the abnormal states using BPNs was achieved 96.4% reliability.

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WC-Co의 열충격 후 파괴 현상과 기계적 성질 (Fracture Behavior and Mechanical properties of WC-Co Subjected to Thermal Shock)

  • 한동빈
    • 한국세라믹학회지
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    • 제27권1호
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    • pp.102-108
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    • 1990
  • WC-Co composites are widely used as cutting or drilling tools because of their high hardness, strength, and fracture toughness. The working temperature is, however, generally in the range of 300-$700^{\circ}C$ so thermal shock fracture of WC-Co can occur. In this study, the strength, fracture toughness and fracture surface of 16wt% Co bonded tungsten carbide composites before and after thermal shock were observed.

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다층퍼셉트론을 이용한 절삭칩 형상과 채터검출에 관한 연구

  • 박동삼
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1992년도 추계학술대회 논문집
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    • pp.293-297
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    • 1992
  • For the computerized monitoring and diagnosis of the undesirable chip chatter which are major obstacles to FMS, a pattern recognition system based on multi-layer perception neural network is developed and the performance of the system is experimentally evaluated. Experimental results show that recognition of the two class state of normal or abnormal cutting gives satisfactory results with success rate of 81`91%. Therefore, the proposed system has possibility for use in monitoring and diagnosis of automatic manufacturing system

선천 매독성 치아기형 1예 보고 (A Case Report of Dental Defects in Congenital Syphilis)

  • 김종열;정순민
    • Journal of Oral Medicine and Pain
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    • 제7권1호
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    • pp.41-46
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    • 1982
  • The patient, 11 yeats old male was examined for routine oral health care. He had been hospitalized for treatment of nephritis. Hos physical condition os mental retarded & undergrowth state. In oral examination, notch on cutting edge and screw-driver shaped crown of maxillary central incisors, narrow crown and dwarfed & pinched occlusal surface of lower first molars and scars(rhagades) on the angle of the lip were shown. We diagnosed the above symptoms as dental defects of congenital syphilis; Huchinson's inscisors and mulberry molar.

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초경절단공구의 인선결손에 관한 연구 (A Study on the Cutting Edge Chipping of Cemented Carbide Cut-off Tools)

  • 김원일
    • 한국정밀공학회지
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    • 제5권1호
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    • pp.71-77
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    • 1988
  • This study applies dynamic deformation analysis to the rake face stress distribution of cemented carbide cut-off tools by turning, using a finite element method. The results are following: 1. The dynamic loaded state of a cut-off tool was very changeable for the first 0.6 seconds. Reaching the normal state, it became in active. 2. Chipping was influnced not only by the magnitude of stress but also by the abrupt change of tensile and compressive stresses. 3. The distribution chat of principal stress by dynamic load and the direction of resultant vector were almost constant regardless of load time.

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초경소재 재활용을 위한 플랫 엔드밀공구의 재연삭 효과 (Regrinding Effect of Flat End-Mill Tool for Recycling of Tungsten Carbide (WC-Co) Material)

  • 강명창;김민욱;권동희;박인덕;정영근
    • 한국재료학회지
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    • 제18권12호
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    • pp.635-639
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    • 2008
  • In this paper, experimental studies of the regrinding of tungsten carbide (WC-Co) tools for high-speed machining were conducted. Regrinding and a subsequent evaluation test were carried out for a flat endmill tool with diameters of 10 mm and 3 mm using a CNC five-axis tool grinder and a CNC three-axis machining center. Tool wear on the two types of endmill tools increased as the cutting length increased, and the tool wear was not influenced by the regrinding state. In case of the micro endmill with a tool diameter of 3 mm, the effective regrinding time was determined for a flank wear threshold of 0.3 mm considering the tool life according to cutting length. The tool lives of the 10 mm and 3 mm endmill tools were increased by 80% and 72%, respectively. This conclusion proves the Feasibility of the recycling of tungsten carbide materials in the high-speed machining of high-hardened materials for industrial applications.

압입하중-변위곡선 분석을 통한 폴리머 소재의 절삭표면상태 예측에 관한 연구 (Prediction of State of Cutting Surfaces of Polymers by Analysis of Indentation Load-depth Curve)

  • 전은채;김재현;제태진
    • 한국기계가공학회지
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    • 제10권4호
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    • pp.76-81
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    • 2011
  • UV imprinting process can manufacture high-functional optical components with low cost. If hard polymers can be used as transparent molds at this process, the cost will be much lower. However, there are limited researches to predict the machinability and the burr of hard polymers. Therefore, a new method to predict them by analyzing load-depth curves which can be obtained by the instrumented indentation test was developed in this study. The load-depth curve contains elastic deformation and plastic deformation simultaneously. The ratio of the plastic deformation over the sum of the two deformation is proportional to the ductility of materials which is one of the parameters of the machinability and the burr. The instrumented indentation tests were performed on the transparent molds of the hard polymers and the values of ratio were calculated. The machinability and the burr of three kinds of hard polymers were predicted by the ratio, and the prediction was in agreement with the experimental results from the machined surfaces of the three kinds of hard polymers.

오스템퍼링한 구상흑연주철(ADI)의 드릴 가공시 경도 및 현미경조직변화에 관한 연구 (A study on the Mechanical characteristics of austempered ductile cast iron to hardness and texture variation in drilling)

  • 조규재
    • 한국생산제조학회지
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    • 제8권1호
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    • pp.81-88
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    • 1999
  • This paper was carried out to know the influence of advanced austempered ductile cast iron (ADI) on the tool life and mechanical properties of drilling machinability. For manufactured method of ADI, the spheroidal graphite cast iron were austenized at 90$0^{\circ}C$ for 1 hour and then austempered for 2 hour at 37$0^{\circ}C$ in the salt bath. And interrelationship has been investigated between tool life and mechanical characteristics of specimen material on drilling condition when the ordinary and step-feed drilling are carried out to drill holes of specimens. Tensile strength and hardness of ADI decrease and elongation of ADI increases with the increase austempered temperature. It is known that about 2 times of tool life in the case of step-feed decreases compared with ordinary feed due to the high hardness of ADI and hardness ascribed to the fact that retained austenite became to martensite state due to cutting heat in drilling. Under the constant feed rate 0.1mm/rev relation between hardness and length of end tip after drilling can be formularized to Hv=$788.46L^{-0.096}$ for the cutting speed 6.1m/min.

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