• 한국생산제조학회지
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• 제8권4호
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• pp.61-67
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• 1999

In turning the chip may be produced in the form of continuous chip or discontinuous one. Continuous chips produced at high speed machining may hit the newly cut workpiece surface and adversely affect the appearance of the surface finish and may interfere with tool and sometimes induce tool fracture. In this study relationship between AE signal and chip form was experimentally investigated, The experimental results show that types of chip form are possible to be classified from the AE signal using fuzzy logic.

• 한국산업융합학회 논문집
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• 제4권2호
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• pp.127-132
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• 2001

In turning, the chip may be produced in the form of continuous chip or discontinuous chip. The continuous chips are dangerous to the operator and difficult to be handled at high speed machining. The signal of AE(Acoustic Emission) is found out to be related to cutting conditions, tool materials, test conditions and tool geometry in turning. In this study, the relationship between AE signal and chip form was experimentally investigated. The experimental results show that the types of chip form are possible to be classified from the AE signal using fuzzy logic.

• 한국생산제조학회지
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• 제23권4호
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• pp.330-336
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• 2014

The continuous chip generated in cutting process deteriorates workpiece, tool, and machine tool system. It is necessary to treat this continuous chip in ductile material machining condition for stable cutting. This paper deals with the chip control method using acoustic emission(AE) signal in pure copper turning operation. AE raw signals, root mean square(RMS) signals and wavelet transformed signals measured in turning process are introduced to analysis for chip patterns. With analysis of AE signals, it is obtained that the produced chip patterns are correlated with the specified AE signals which are transformed by fuzzy pattern algorithm. By this experimental investigation, the chip patterns can be classified at significant level in pure copper machining process and controlled from continuous chips to reduced-length stable chips.

• 전기학회논문지
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• 제56권3호
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• pp.561-565
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• 2007

We propose glass and PDMS (polydimethylsiloxane) chips for DNA amplification with continuous-flow PCR (polymerase chain reaction). The PDMS microchannel was fabricated using a negative molding method for sample injection. Three heaters and sensors of ITO (indium-tin-oxide) thin films were fabricated on glass chip. ITO heaters and sensors were calibrated accurately for the temperature control of the liquid flow. ITO heater generated stable heat versus applied power. ITO sensor resistance was changed linearly versus temperature increase as a RTD (resistance temperature detector) sensor. As a result, we enable precision temperature control of continuous-flow PCR chip. Using the continuous-flow PCR chip DNA plasmid pKS-GFP 720 bp was successfully amplified.

• 대한기계학회논문집A
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• 제29권1호
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• pp.53-58
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• 2005

We present a high-throughput continuous cell separation chip using hydrodynamic dielectrophoresis (DEP) process. The continuous cell separation chip uses three planar electrodes in a separation channel, where the positive DEP cells are moved away from the central streamline while the negative DEP cells remain in the central streamline. In the experimental study, we use the mixture of viable (live) and nonviable (dead) yeast cells in order to obtain the continuous cell separation conditions. For the conditions of the electric fields frequency of 5MHz and the medium conductivity of $5{\mu}S/cm$, the fabricated chip performs a continuous separation of the yeast cell mixture at the varying flow-rate in the range of $0.1{\sim}{\mu{\ell}/min$.; thereby, resulting in the purity ranges of $95.9{\sim}97.3\%\;and\;64.5{\sim}74.3\%$ respectively for the viable and nonviable yeast cells. present chip demonstrates the constant cell separation performance for varying mixture flow-rates.

• 한국생산제조학회지
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• 제7권2호
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• pp.40-46
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• 1998

In order to achieve high flexibility in manufacture, chip control is one of the most serious problems at present. The continuous type chip (uncontrolled chip), which interrupts the normal cutting process and damages the operator, tool and workpiece have a higher force ratio. while the controlled chip which is 6 or 9 type and C type, has the values of the force ratio below 0.6 The chips were classified by 4 types. in chip formation and by described chip history during the cutting process. Finally, the feasibility of utilizing force ratios in chip control will be pointed out while comparing generated force signals during the cutting process.

• 한국공작기계학회논문집
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• 제10권3호
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• pp.75-82
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• 2001

The continuous chip in turning operation deteriorates the precision of workpiece and can cause a hazardous condition to operator. Thus the chip form becomes a very important task for reliable turning process. The chip form is identified using the neural network of supervise data Through the measurement of energy radiated from the chip. The feed mechanism os adjusted in order to break continuous chip according to the result of the chip form recognition and it shows a good approach for precision turning operation.

• 동력기계공학회지
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• 제4권4호
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• pp.108-115
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• 2000

The continuous chip in turning operation deteriorates the precision of workpiece and can cause a hazardous condition to operator. Thus the chip form control becomes a very important task for reliable turning process. Using the difference of energy radiated from the chip, the chip form is identified using the neural network of supervised data. The feed mechanism is adjusted in order to break continuous chip according to the result of the chip form recognition and shows a good approach for precision turning operation.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1993년도 춘계학술대회 논문집
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• pp.300-304
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• 1993

Chip formation control is an important problem in the automation of manufacturing process, since the continuous chip can cause catastrophic failures of the tooling and entangle the workpiece causing damage. However, it is impossible to predict chip form correctly due to the complex nature of cutting process. In order to detect the chip form for unmanned manufacturing, a new identification method is proposed. The feasibility of using acoustic emission signals from the sensing plate for identification of chip form is investigated. Experiments were conducted under the various cutting conditions. When the acoustic emission sensor is attached to the sensing plate, it turns out that the moving averaged AE signals correlated well with the collision of segmented chips with the plate. The sensitivity of moving averaged AE signals to chip congestions due to continuous chip formation is illustrated as well.

• 한국미생물·생명공학회지
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• 제16권3호
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• pp.205-212
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• 1988

Saccharomyces formosensis를 wood chip과 alginate gel에 고정화 실험을 한 결과, 모두 효모 고 정화도 매우 높으므로 고정화를 인한 Support로서 적절한 것으로 판단되었다. 관형발효기에 효모를 고 정화한 wood chip 및 alginate gel를 충전하여 연속발효 실험을 수행한 경우 0.446-0.485g EtOH/ g glucose로서 비슷하였으나, cell 수율은 alginate gel의 경우가 wood chip의 경우보다 낮아서 down stream의 처리시 유리하였다. 관형발효기의 에탄을 생산성은 wood chip을 이용할 경우 정상상태에서 에탄을 농도 68.3-54.9g/$\ell$ 범위에서 17.1-32.6g EtOH/$\ell$.hr를 나타내었고, alginate gel을 이용할 경우 정상상태에서 에탄올 농도 80.0-56.8g/$\ell$범위에서 에탄올 생산성은 20.0-32.0g EtOH/ hr를 얻었다. 본 실험의 에탄올 생산성은 다른 고정화법에 비하여 높았으며, 고정화 방법 중 alginate gel을 이용한 고정화법은 에탄을 생산을 위하여 효과적인 에탄을 생산 방법으로 사료되었다.