• Title/Summary/Keyword: Cutting depth factor

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Diamond turning of pick-up lens for optical application (광 정보저장용 픽업 렌즈의 다이아몬드 터닝 가공)

  • 박순섭;김대중;이봉주;김상석;김정호;유영문;김주하
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.525-528
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    • 2003
  • The aspherical lens are used as objective lens of optical pickup. The sample product is made before manufacturing the injection mould of lens to examine the design factor. The optimum cutting conditions of the main spindle speed, the depth of cut, the feed rate are found when we cut PMMA and PC lens sample with ultra-precision SPDT. The demanded surface roughness 10 nm Ra. aspherical form error 0.5 ${\mu}{\textrm}{m}$ P-V for aspherical lens of optical data storage device are satisfied for PMMA. but not satisfied for PC.

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Modeling Cutter Swept Angle at Cornering Cut

  • Chan, K.W.;Choy, H.S.
    • International Journal of CAD/CAM
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    • v.3 no.1_2
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    • pp.1-12
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    • 2003
  • When milling concave corners, cutter load increases momentarily and fluctuates severely due to concentration and uneven distribution of material stock. This abrupt change of cutter load produces undesirable machining results such as wavy machined surface and cutter breakage. An important factor for studying cutter load in 2.5D pocket milling is the instantaneous Radial Depth of Cut (RDC). However, previous work on RDC under different corner-cutting conditions is lacking. In this different corner shapes. In our work, we express RDC mathematically in terms of the instantaneous cutter engage angle which is defined as Cutter Swept Angle (CSA). An analytical approach for modeling CSA is explained. Finally, examples are shown to demonstrate that the proposed CSA modeling method can give an accurate prediction of cutter load pattern at cornering cut.

Pick-up Lens Manufacturing for Optical application using Diamond Turning Process (다이아몬드 터닝가공을 이용한 광정보저장용 픽업렌즈 제작)

  • Kim, J.H.;Kim, S.S.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.04a
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    • pp.47-51
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    • 2004
  • The aspherical lens are used as objective lens of optical pickup. The sample product is made before manufacturing the injection mould of lens to examine the design factor. The optimum cutting conditions of the main spindle speed, the depth of cut, the feed rate are found when we cut PMMA and PC lens sample with ultra-precision SPDT. The demanded surface roughness 10 nm Ra, aspherical form error 0.5 ${\mu}m$ P-V for aspherical lens of optical data storage device are satisfied for PMMA, but not satisfied for PC.

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DIFFERENTIAL DIAGNOSIS OF CLASS III PROFILE (III급 부정교합자의 연조직 측모 감별에 관한 연구)

  • Hwang, Byung-Nam;Rhee, Seung-Hoon;Lee, Jeong-Keun;Lee, Jai-Bong
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.22 no.2
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    • pp.174-183
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    • 2000
  • This study was performed to investigate the characteristics of soft tissue profile of the class III malocclusion and to test the yardstick far differential diagnosis between surgical and orthodontic patients. Initial lateral cephalograms of orthodontic group(30 patients) that have acceptable occlusion and profile by orthodontic treatment alone and surgical group(30 patients) that have favorable occlusion and profile by combined surgical-orthodontic treatment were selected in Ajou university hospital. Powell and Burstone II analysis were made on the tracing. Descriptive, comparative, factor, cluster, and discriminant analysis were carried out with computer program. The results were as followings : 1. Patients who received surgery had a more concave profile and a longer lower facial height than patients who received orthodontic treatment alone. 2. Nasolabial angle, ratio of vertical height, and mentolabial sulcus were significantly different at the 5% level. And facial protuberance, upper lip protuberance, mentocervical angle, nasofrontal angle, nasomental angle, mandibular vertical height, angle between cervix and lower face, ratio of mandibular vertical height divided by cervical depth, ratio of vertical height between upper and lower lip, and maxillary protuberance were significantly different at the 1% level. 3. 8 factors were extracted and factor 2, 3, and 8 showed significant differences by factor analysis. 4. Orthodontic group (25) and surgical group (35) were classified by cluster analysis. 5. Discriminant function was D = 0.079Nasomental angle + 0.081Sn-Gn + 3.343Sn-Gn/C-Gn + 1.734Sn-St/St-Me' -26.460, and cutting score was 0, so we can discriminate that orthodontic group has the score above 0, and surgery group below 0. And 91.7% of original grouped cases were correctly classified.

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A Study on the Quantitative Analysis of Cutting Parameters and Prediction Model for Surface Roughness in Milling (밀링가공에서 표면거칠기에 대한 절삭인자의 정량적 분석과 예측모델에 관한 연구)

  • Jang, Sung-Min;Kang, Shin-Gil
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.16 no.3
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    • pp.125-130
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    • 2017
  • In this study, the influence of various factors on surface roughness was investigated using the Taguchi experimental method through high-speed machining processing. Feed rate, pitch, tool diameter, and depth of cut are widely applied to high-speed machining conditions for mold production. Each of these factors was implemented and classified into three levels; then, after high speed machining, surface roughness was measured, the S/N ratio was analyzed, and the influence on the surface roughness of control factors was analyzed quantitatively by ANOVA. Using this information, a mathematical model for predicting surface roughness was derived from multiple regression analysis. This mathematical model enables the surface roughness value after high-speed machining to be predicted at the production stage, before machining, for a wide range of machining conditions.

Application of Response Surface Methodology for Modeling and Optimization of Surface Roughness and Electric Current Consumption in Turning Operation (선삭 작업에서 표면조도와 전류소모의 모델링 및 최적화를 위한 반응표면방법론의 응용)

  • Punuhsingon, Charles S.C.;Oh, Soo-Cheol
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.13 no.4
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    • pp.56-68
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    • 2014
  • This paper presents an experiment on the modeling, analysis, prediction and optimization of machining parameters used during the turning process of the low-carbon steel known as ST40. The parameters used to develop the model are the cutting speed, the feed rate, and the depth of the cut. The experiments were carried out under various conditions, with three level of parameters and two different treatments for each level (with and without a lubricant), to determine the effects of the parameters on the surface roughness and electric current consumption. These effects were investigated using response surface methodology (RSM). A second-order model is used to predict the values of the surface roughness and the electric current consumption from the results of experiments which collected preliminary data. The results of the experiment and the predictions of the surface roughness and electric current consumption under both treatments were found to be nearly identical. This result shows that the feed rate is the main factor that influences the surface roughness and electric current consumption.

A Study for Determining the Rehabilitation Method Group using NHPCI on Asphalt Concrete Pavement of National Highway (국도 아스팔트 포장의 NHPCI(National Highway Pavement Condition Index)를 활용한 보수공법그룹 결정에 관한 연구)

  • Son, Hyeon Jang;Kwon, Soo-Ahn;Lee, Jae Jun;Baek, Cheolmin;Lim, Jae Kuy;Sin, Hyun Jin
    • International Journal of Highway Engineering
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    • v.15 no.2
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    • pp.1-9
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    • 2013
  • PURPOSES : The PMS(Pavement Management System) has been utilized in order to efficiently allocate the limited budget for the maintenance of national highway system. In the PMS of national highway, surface pavement condition is evaluated by using the VI (Visual Index). However, the VI is determined only by considering the cracking rate (%) and rut depth (mm), which is not reflecting the IRI (International Roughness Index) that is known as an important factor of pavement performance. In this study, the NHPCI (National Highway Pavement Condition Index) which includes the cracking rate (%), rut depth (mm), and IRI (m/km) is suggested for determining the rehabilitation methods group. METHODS : First, the rehabilitation methods performed between 2008 and 2010 on the national highway is classified and then, NHPCI is determined for each rehabilitation method. Next, the NHPCI for each rehabilitation method is grouped through the interval estimation of the population mean and T-test analysis. RESULTS : According to NHPCI range, the rehabilitation methods are divided into four categories: Not Required, Preventive Maintenance, Overlay Treatment (with or without cutting), and Full-scale Treatment (i.e., reconstruction). CONCLUSIONS : Based on this study, it is recommended that the appropriate NHPCI range should be determined through the combination of the rehabilitation categories and Decision Procedure of Pavement Distress Condition Visual Index.

Slopes Risk Assessment Techniques through Pattern Classification (패턴분류를 통한 산지사면의 위험도 평가 기법)

  • Kim, Min-Seub;Kim, Jin-Young
    • The Journal of Engineering Geology
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    • v.25 no.2
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    • pp.189-199
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    • 2015
  • Our country's leading granite weathered soil of the ground slope failures that occur in cutting slope most cases, it does not require in-depth to the shear strength most of the surface layer is affected by weathering (1~2 m) at a shallow depth close to the ground, it is important to identify the reliability. Based on the result obtained in actual field investigation, the field slope type was classified by each type of wedge slope, Infinite slope, finite slope -I and finite slope -II, and the slope stability was examined respectively. In addition, using the numerical analysis results, the relationship between the slope inclination angle and safety factor was analyzed and it tried to offer basic data to which the stability in the field slope was able to be estimated by analyzing the safety factor change of the slope according to the slope type. In this study, classified into four types of natural slope, safety factor estimation method by slope types is proposed through the numerical analysis. However, some limit exists in generalizing in this research because it does not test various case studies. Therefore, the case study of a wide range of various sypes to assess the safety of various types slope can be made, accommodate a wide range of field conditions reasonable risk evaluation criteria may be derived.

Multiple Stakeholder Perspectives on Cancer Stigma in North India

  • Gupta, Adyya;Dhillon, Preet K;Govil, Jyotsna;Bumb, Dipika;Dey, Subhojit;Krishnan, Suneeta
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.14
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    • pp.6141-6147
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    • 2015
  • Background: Cancer is a leading cause of death worldwide. A large proportion of cancer deaths are preventable through early detection but there are a range of social, emotional, cultural and financial dimensions that hinder the effectiveness of cancer prevention and treatment efforts. Cancer stigma is one such barrier and is increasingly recognized as an important factor influencing health awareness and promotion, and hence, disease prevention and control. The impact and extent of stigma on the cancer early detection and care continuum is poorly understood in India. Objectives: To evaluate cancer awareness and stigma from multiple stakeholder perspectives in North India, including men and women from the general population, health care professionals and educators, and cancer survivors. Materials and Methods: A qualitative study was conducted with in-depth interviews (IDIs) and focus group discussions (FGDs) among 39 individuals over a period of 3 months in 2014. Three groups of participants were chosen purposively - 1) men and women who attended cancer screening camps held by the Indian Cancer Society, Delhi; 2) health care providers and 3) cancer survivors. Results: Most participants were unaware of what cancers are in general, their causes and ways of prevention. Attitudes of families towards cancer patients were observed to be positive and caring. Nevertheless, stigma and its impact emerged as a cross cutting theme across all groups. Cost of treatment, lack of awarenes and beliefs in alternate medicines were identified as some of the major barriers to seeking care. Conclusions: This study suggests a need for spreading awareness, knowledge about cancers and assessing associated impact among the people. Also Future research is recommended to help eradicate stigma from the society and reduce cancer-related stigma in the Indian context.

Exploratory Study on the Success Factors of SPA Brands from Marketing Perspectives -Based on Grounded Theory- (SPA 브랜드의 마케팅 성공요인 탐색 -근거이론을 중심으로-)

  • Kim, Kyung Ran;Yang, Su Jin
    • Journal of the Korean Society of Clothing and Textiles
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    • v.39 no.2
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    • pp.190-203
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    • 2015
  • The fashion industry has been rearranged by Global SPA brands (like ZARA and H&M), which are powerful retailers that integrate the value chain ranging from manufacturing to sales. SPA brands can offer good quality of clothing at a reasonable price by cutting the margin between the supply chain. They are also called fast fashions since they make expedited efforts to respond to market trends and consumers. Despite the slow growth of the fashion industry in Korea, as global SPA brands rapidly expand market share, traditional fashion companies have launched several SPA brands such as MIXXO and SPAO (E-LAND), 8SECONDS (CHEIL INDUSTRIES). The few academic studies on this subject are focused on the analysis of secondary data such as news and books. The current research is qualitative and empirical attempts to explore the success factor of SPA brands with analysis of 1:1 in-depth interviews with experts who have worked for global SPAs such as Uniqlo, H&M, and ZARA, based on the grounded theory. The main phenomenon was shown to be that global SPA brands were popular since they offer a variety of products with a large assortment at reasonable and cheap prices in a large scale and multifunctional retail store. Most of them displayed main phenomena that can be realized due to the purchasing cycle of clothing that is shorter with consumers' regarding clothing as consumables. Global SPA brands had three types of marketing strategy: sellable product, sales strategy according to consumer response, and multifunctional stores. Each global SPA brand developed marketing strategies based on core competency and national conditions. The three success factors shorten the consumer decision making process of clothing. This study concludes with implications for practitioners of SPA brands born in Korea.