• 제목/요약/키워드: Processing pressure

검색결과 1,594건 처리시간 0.03초

Sand Blast를 이용한 Glass Wafer 절단 가공 최적화 (Optimization of Glass Wafer Dicing Process using Sand Blast)

  • 서원;구영보;고재용;김구성
    • 한국세라믹학회지
    • /
    • 제46권1호
    • /
    • pp.30-34
    • /
    • 2009
  • A Sand blasting technology has been used to address via and trench processing of glass wafer of optic semiconductor packaging. Manufactured sand blast that is controlled by blast nozzle and servomotor so that 8" wafer processing may be available. 10mm sq test device manufactured by Dry Film Resist (DFR) pattern process on 8" glass wafer of $500{\mu}m's$ thickness. Based on particle pressure and the wafer transfer speed, etch rate, mask erosion, and vertical trench slope have been analyzed. Perfect 500 um tooling has been performed at 0.3 MPa pressure and 100 rpm wafer speed. It is particle pressure that influence in processing depth and the transfer speed did not influence.

The Effect of Pressure on the Properties of Carbon/Carbon Composites during the Carbonization Process

  • Joo, Hyeok-Jong;Oh, In-Hwan
    • Carbon letters
    • /
    • 제3권2호
    • /
    • pp.85-92
    • /
    • 2002
  • 4D carbon fiber preforms were manufactured by weaving method and their carbon fiber volume fractions were 50% and 60%. In order to form carbon matrix on the preform, coal tar pitch was used for matrix precursor and high density carbon/carbon composites were obtained by high densification process. In this process, manufacture of high density composites was more effective according to pressure increasement. When densificating the preform of 60% fiber volume fraction with 900 bar, density of the composites reached at 1.90 $g/cm^3$ after three times processing. Degree of pressure in the densification process controls macro pore but it can not affect micro pore. During the carbonization process, micro pore of the preform were filled fully by once or twice densification processing. But micro pore were not filled easily in the repeating process. Therefore, over three times densification processing is the filling micro pore.

  • PDF

저온 나노임프린트 공정에서 압력과 폴리머 레지스트 초기 두께의 영향 (Effect of Pressure and Initial Polymer Resist Thickness on Low Temperature Nanoimprint Lithography)

  • 김남웅;김국원;신효철
    • 한국공작기계학회논문집
    • /
    • 제18권1호
    • /
    • pp.68-75
    • /
    • 2009
  • A major disadvantage of thermal nanoimprint lithography(NIL) is the thermal cycle, that is, heating over glass transition temperature and then cooling below it, which requires a significant amount of processing time and limits the throughput. One of the methods to overcome this disadvantage is to make the processing temperature lower Accordingly, it is necessary to determine the effects on the processing parameters for thermal NIL at reduced temperatures and to optimize the parameters. This starts with a clear understanding of polymer material behavior during the NIL process. In this work, the squeezing and filling of thin polymer films into nanocavities during the low temperature thermal NIL have been investigated based upon a two-dimensional viscoelastic finite element analysis in order to understand how the process conditions affect a pattern quality; Pressure and initial polymer resist thickness dependency of cavity filling behaviors has been investigated.

Effect of residual oxygen in a vacuum chamber on the deposition of cubic boron nitride thin film

  • Oh, Seung-Keun;Kang, Sang Do;Kim, Youngman;Park, Soon Sub
    • Journal of Ceramic Processing Research
    • /
    • 제17권7호
    • /
    • pp.763-767
    • /
    • 2016
  • The structural characterization of cubic boron nitride (c-BN) thin films was performed using a B4C target in a radio-frequency magnetron sputtering system. The deposition processing conditions, including the substrate bias voltage, substrate temperature, and base pressure were varied. Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy were used to analyze the crystal structures and chemical binding energy of the films. For the BN film deposited at room temperature, c-BN was formed in the substrate bias voltage range of -400 V to -600 V. Less c-BN fraction was observed as the deposition temperature increased, and more c-BN fraction was observed as the base pressure increased.

Effects of Main Shaft Velocity on Turbidity and Quality of White Rice in a Rice Processing System

  • Cho, Byeong-Hyo;Kang, Tae-Hwan;Won, Jin-Ho;Kang, Shin-Hyeong;Lee, Hee-Sook;Han, Chung-Su
    • Journal of Biosystems Engineering
    • /
    • 제42권1호
    • /
    • pp.69-74
    • /
    • 2017
  • Purpose: The purpose of this study is to analyze turbidity and quality characteristics of white rice as a function of main shaft blast velocity and to verify the optimum processing conditions in the cutting type white rice processing system (CTWRPS). Methods: Sindongjin, one of the rice varieties, which used to be produced in Gimje-si, Jeollabuk-do, in 2015, was used as the experimental material. Turbidity and quality characteristics of white rice were measured at three different main shaft blast velocities: 25, 30, and 35 m/s. The amount of test material used for a single experiment was 20 kg, and after processing, whiteness was found to be $42.5{\pm}0.5$, following which, turbidity and quality characteristics were measured. Results: Turbidity decreased with increase in the shaft blast velocity, and as a result, was lowest at 35 m/s of shaft blast velocity among all the other experiment velocities. The trend of cracked rice ratios was similar to the turbidity. Broken rice ratio turned out to be less than 2.0% in all the test conditions. In the first stage of processing, the processing pressure decreased as the main shaft blast velocity increased. Additionally, in the second stage of processing, the processing pressure was at its lowest value at the main shaft blast velocity of 35 m/s. Energy consumption, too, decreased as the main shaft blast velocity was increased. Conclusions: From the above results, it is concluded that the main shaft blast velocity of 35 m/s is best for reducing turbidity and producing high quality rice in a CTWRPS.

릴럭턴스를 이용한 Reluctive Pressure Transducer의 설계 (The Design using the reluctance of Reluctive Pressure Transducer)

  • 조항신;박희성;주형준;성세진;이기홍
    • 전력전자학회:학술대회논문집
    • /
    • 전력전자학회 1998년도 전력전자학술대회 논문집
    • /
    • pp.328-331
    • /
    • 1998
  • Because of the powerful tolerance of overload, dynamic response and anti-erosion, Reluctive Pressure Transducer(RPT), as a measuring element of oil pressure equipment is applied to the measuring system of vessels, air craft. The Electrical reluctance appeared in the pressed diaphragm. To process the reluctance as a electric signal, bridge circuit is used. The design using the reluctance of pressure sensor is described in this paper. For the high efficiency of the sensitive RPT, pressure sensor structure is presented and electrical signal processing is simulated.

  • PDF

Effects of High-Pressure, Microbial Transglutaminase and Glucono-δ-Lactone on the Aggregation Properties of Skim Milk

  • Lee, Sang Yoon;Choi, Mi-Jung;Cho, Hyung-Yong;Davaatseren, Munkhtugs
    • 한국축산식품학회지
    • /
    • 제36권3호
    • /
    • pp.335-342
    • /
    • 2016
  • The object in this study is to investigate the effects of high pressure and freezing processes on the curdling of skim milk depending on the presence of transglutaminase (TGase) and glucono-δ-lactone (GdL). Skim milk was treated with atmospheric freezing (AF), high pressure (HP), pressure-shift freezing (PSF) and high pressure sub-zero temperature (HPST) processing conditions. After freezing and pressure processing, these processed milk samples were treated with curdling agents, such as TGase and GdL. Pressurized samples (HP, PSF and HPST) had lower lightness than that of the control. In particular, PSF had the lowest lightness (p<0.05). Likewise, the PSF proteins were the most insoluble regardless of whether they were activated by TGase and GdL, indicating the highest rate of protein aggregation (p<0.05). Furthermore, the TGase/GdL reaction resulted in thick bands corresponding to masses larger than 69 kDa, indicating curdling. Casein bands were the weakest in PSF-treated milk, revealing that casein was prone to protein aggregation. PSF also had the highest G' value among all treatments after activation by TGase, implying that PSF formed the hardest curd. However, adding GdL decreased the G' values of the samples except HPST-treated samples. Synthetically, the PSF process was advantageous for curdling of skim milk.

On Employing Nonparametric Bootstrap Technique in Oscillometric Blood Pressure Measurement for Confidence Interval Estimation

  • Lee, Yong-Kook;Lee, Im-Bong;Chang, Joon-Hyuk;Lee, Soo-Jeong
    • 한국멀티미디어학회논문지
    • /
    • 제17권2호
    • /
    • pp.200-207
    • /
    • 2014
  • Blood pressure (BP) is an important vital signal for determining the health of an individual subject. Although estimation of mean arterial blood pressure is possible using oscillometric blood pressure techniques, there are no established techniques in the literature for obtaining confidence interval (CI) for systolic blood pressure (SBP) and diastolic blood pressure (DBP) estimates obtained from such BP measurements. This paper proposes a nonparametric bootstrap technique to obtain CI with a small number of the BP measurements. The proposed algorithm uses pseudo measurements employing nonparametric bootstrap technique to derive the pseudo maximum amplitudes (PMA) and the pseudo envelopes (PE). The SBP and DBP are then derived using the new relationships between PMA and PE and the CIs for such estimates. Application of the proposed method on an experimental dataset of 85 patients with five sets of measurements for each patient has yielded a smaller Cl than the conventional student t-method.

포트홀 다이를 이용한 중공튜브 압출 제품의 다이 챔버 형상에 따른 결합력에 대한 연구 (A Study on the Welding Pressure of Extrusion Processing of Hollow Tube Using the Porthole Die with the Different Chamber Shape)

  • 김민규;진인태;정영득;하만경
    • 한국소성가공학회:학술대회논문집
    • /
    • 한국소성가공학회 2001년도 춘계학술대회 논문집
    • /
    • pp.110-114
    • /
    • 2001
  • The welding pressure in porthole die extrusion is affected by the shape of welding chamber. It is very important to increase the welding pressure when the tube is used particulary as the materials of hydroforming processing. The high circumferential stress of the tube would make the welding pressure increase during the porthole die extrusion. In order to increase the circumferential stress, it is necessary to make the billets pass through the narrow gap between the conical die and the conical mandrel. This paper describes the welding pressure by the experiments with the two types of the chamber. One of them is the chamber between the flat die and straight mandrel, and the other one is the chamber between the conical die and conical mandrel. The result of the experiments show that the conical chamber makes the welding pressure increase by the effect of the reducing the diameteres of tube.

  • PDF

대기압 화염 플라즈마 처리가 강판의 표면 및 고무와의 접착특성에 미치는 영향 (Effect of Atmospheric Pressure Flame Plasma Treatment on Surface and Adhesive Bonding Properties between Steel Plate and Rubber)

  • 류상렬;이동주
    • Composites Research
    • /
    • 제23권5호
    • /
    • pp.1-7
    • /
    • 2010
  • NBR과 강판의 접착특성을 향상시키기 위해 대기압 화염 플라즈마(APFP) 처리 장치가 사용되었다. 가장 우수한 접착특성을 나타내는 최적 조건을 찾기 위해 다양한 처리 조건(처리속도, 거리)에 따른 효과에 대한 실험적 연구를 하였다. 주어진 조건에서 버너 포트와 강판의 최적 거리는 40mm, 버너 포트의 최적 처리속도는 50m/min였다. APFP 처리 후 접착제를 두 번 도포한 강판의 접착강도는 접착제만 도포한 경우보다 20.5% 증가하였다. 본 연구를 통해서 대기압 화염 플라즈마 처리에 의한 강판의 표면개질이 고무와 강의 접착강도를 증가시키는 적절하면서도 응용이 가능한 방법임을 확인하였다.