• Journal of Power System Engineering
• /
• v.20 no.2
• /
• pp.43-50
• /
• 2016

This research proposal is based on a novel non-contact technique of micro-sized bead injection process for fabrication of electronic paper display. This non-contact injection process is based on the principle of electrostatic force and uses micro-sized metal-coated beads dispersed in a solution. The dispersion retention times of three different solutions with viscosities of 10 cps, 100 cps, and 1000 cps were measured by optical equipment showing the retention times of 5 mins, 10 mins, and 30 mins respectively. The dispersion retention rate dropped as the time passed. The dispersion retention characteristic of 1000 cps solution was more stable as compared to those of 10 cps and 100 cps meaning that higher viscosity has better retention properties. The experimental results of bead injection at different viscosity levels of the solution were also measured and a stable injection result was achieved by using 1000 cps solution. This results show that stable injection is dependent on solution viscosity and dispersion.

• Design & Manufacturing
• /
• v.6 no.2
• /
• pp.12-16
• /
• 2012

In this study, an injection mold is made to produce polymer line post insulators. FRP (fiber reinforced plastics) is covered by silicone housing. In injection molding process, chances for offcenter are 60 percent. Given the structure of the product, offcenter occurs owing to the imbalances in positions of gates and improper -designs of cores and jigs. This study focuses on mold modifications and improvements.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.28 no.2
• /
• pp.154-159
• /
• 2004

A new microflow rate controller for medical injection was developed and evaluated. The flow rate was controlled by changing the friction depth as well as the friction length of the micro-channel. A precise micro-fabrication of the micro-channel was requested for an accurate flow control. The friction depth was inversely proportional to the friction length, which gives a linear flow control to the channel length. The channel groove was fabricated with a plastic material. A rubber containing silicone oil was covered over the groove, which satisfies both lubrication and leakage prevention. The flow controller was validated by performing the numerical simulation and experiment. A good agreement was shown between computation and experiment.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.11
• /
• pp.74-80
• /
• 1999

In this study, a stereolithography apparatus (SLA) prototype is used as a master model to be transformed into the silicone pattern by vacuum tool forming. The tool for the first prototype is fabricated by using this silicone pattern. Following this procedure, a temporary tool with metal powder and epoxy for wax injection is prepared for the die set of quick change type which consists of upper and lower base die나 and an insert die. The die set of quick change type appears to be very effective in casting operation by changing tools rapidly. The original wax pattern is formed through the die set, and is made of lost-was. Finally the lost-wax pattern is applied to investment casting. The final casting product is checked regarding its dimensional accuracy.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.23 no.2
• /
• pp.206-212
• /
• 2014

Liquid silicone rubber (LSR) has been widely used in automotive, electrical, and medical components. Thus, research on the use of LSR in the injection molding process is required to obtain high-quality and high-performance products. In this study, a mold was fabricated to examine the effects of the process parameters on the molding and mechanical properties of LSR parts. A computer-aided engineering analysis was used to optimize the air vent depth and curing temperature to decrease the flash at the air vents caused by the low viscosity of LSR. Temperature and pressure sensors were mounted in the mold to determine the effects of the process parameters on the temperature and pressure in the cavity. The tensile strength of the LSR parts was also examined in relation to the process parameters.

• Archives of Plastic Surgery
• /
• v.37 no.6
• /
• pp.749-757
• /
• 2010

Purpose: Since skin sparing mastectomy removes the mammary gland and the nipple-areolar complex preserving all mammary skin, it makes the widespread use of implants in immediate reconstruction. This article reports our experience in immediate breast reconstruction after skin sparing mastectomy by using the silicone implants in patients especially who have small to moderate sized and minimal ptotic breast. Methods: From September of 2007 to July of 2009, we performed breast reconstruction for 44 breasts of 40 women with silicone implant after mastectomy. Tumors were divided into 5 malignant types (21 IDC, 18 DCIS, 2 ILC, 2 phylloides tumor, 1 mucinous carcinoma). The implant is placed in a submuscular pocket or in a submuscularsubfascial pocket depending upon the condition of the muscles and skin flaps after mastectomy. Results: The mean age was 47 years and the average follow-up period was 11 months. Cosmetic outcome was assessed by evaluation of photographs and assessment of breast volume and shape, breast symmetry, and overall outcome. About 80% of each of these parameters was scored as good or excellent. Breast complication was developed in a total of 6 cases including 2 capsular contracture, 2 partial skin necrosis due to blue dye injection and 2 implant infection. Conclusion: The use of definitive implants in a skin sparing mastectomy is a one-stage immediate breast reconstruction with low morbidity and acceptable result. This method is considered reliable with favorable aesthetic result.

• Korean Journal of Community Nutrition
• /
• v.3 no.3
• /
• pp.430-439
• /
• 1998

This study was performed to investigate the nutritional status of neurosurgical tube-fed patients. The objective of this study was to improve the nutrition management of tube-fed patients. The current practices of tube feeding and enteral nutrition formula as for 95 patients in the hospital were examined by reviewing patients charts, and interviewing patients, nurses and their family members. The results are summarized as follows ; 57.9% of patients that received the formula showed a decrease in mental status. Among the subjects, 55.7% had nervous system diseases due to old age. Most of the tube-fed patients were hospitalized in the emergency room and while hospitalized, the status of their respiratory organ was abnormal. The method of tube-feeding was by Bolus injection and the type of the tube was a 16Fr size silicone tube. The amount of the injection per day while tube-feeding was on average 1424kcal for men and 1322kcal for women and the calories per day ranged from 1000-1500kcal(50.5%). The injection volume averaged 332.7ml and 45% of patients received more than 300ml per injection. The tube feeding intake rate was 127.9ml/min with 50% of subjects in the range of 50-100ml/min and 10% at 20ml/min. The longer the hospitalization, the older age, coma status, and the higher tube feeding rate, the more decreased were the biochemical parameters.

• Proceedings of the KSLP Conference
• /
• 1998.11a
• /
• pp.195-195
• /
• 1998

성문부폐쇄부전(glottic insufficiency)를 수술적으로 치료하기 위한 노력은 여러 형태(silicone, hydrogen gel, teflon, etc.)의 성대이물주입술, 갑상성형술등 다양하게 시도되어 왔다. 그러나, 이러한 노력에도 불구하고 성문부폐쇄부전은 여전히 해결하기 어려운 문제로 남아있다. 여기에 1995년 Ford 등은 성문부폐쇄부전에 이은 음성장애치료의 새로운 접근방법으로 자가 콜라겐주입술(autologous collagen injection)을 소개하였다. (중략)

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.12
• /
• pp.7-13
• /
• 1999

The potential for growth and the future impact of Rapid Prototyping that it will have on the product development cycle are enormous. Since making tools, precedes making parts, Rapid Tooling becomes widely used in automobile, aerospace, electronic, and other industries. In this study, master models formed by Rapid Prototyping of Stereolithography have been applied for vacuum casting to obtain silicone patterns which have transformed into epoxy models. The epoxy models have been measured to check dimension errors, and tested their functions. These checking and measurement have provided information on plastic injection possibilities and data for die design, Temporary die making with the materials of Aluminum/Epoxy and powder injection metal (PIM) has also been discussed in terms of hardness, surface roughness, and SEM microstructures.

• Electrical & Electronic Materials
• /
• v.7 no.1
• /
• pp.64-72
• /
• 1994

본 고는 현재 전기적 응용을 위한 수지 절연물의 진공/가압 수지-주형처리 분야에서 가장 앞선 기술과 연구개발력을 보유하고 있는 스위스의 Ciba-Geigy사와 최신의 진공성형 시스템을 개발, 생산하고 있는 독일의 Hedrich사 및 진공주형/자동가압 성형장비를 생산하는 스위스의 Vogel사 등을 최근에 방문하여 Epoxy, Polyurethane, Polyester 및 Silicone 수지 등의 수지절연시스템을 가지고 구조적으로 기포가 없으며 전기적, 기계적, 열적특성이 매우 우수하고 매끄러운 표면이 요구되는 수지 mold제품을 생산하는데 적용되고 있는 진공 수지-주형처리기술의 현황과 아울러 경화시간을 크게 단축시켜 생산자동화가 가능한 최신의 자동가압겔화(Automatic pressure gelation)/주입몰드공정(Injection molding process)의 특징 및 기술개발현황에 대해 파악한 내용을 소개하고자 한다.