• 대한골관절종양학회지
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• 제10권2호
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• pp.71-78
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• 2004

목적: 최근 체험한 59례의 거대 세포종 중 골 소파술 및 시멘트 충전술을 시행한 37례의 재발의 특성과 이를 예방할 수 있는 방법에 대해 알아 보고자 한다. 대상 및 방법: 1995년 1월부터 2000년 3월까지 본원 정형외과에 입원하여 진단적 생검 또는 수술적 치료에 의하여 병리학적으로 거대 세포종으로 확진되고, 그 치료로 골 소파술과 Burring 후 시멘트 충전술을 시행했던 3 7례의 재발의 위치, 특성, 시기에 관하여 분석하였다. 결과: 총 37례 환자 중 일차 치료(Curettage & Cementation) 후 13례에서 재발하여 35%의 재발율을 보였다. 일차 치료 후 재발까지의 기간은 평균 16 개월로 분석되었으며, 최단 5개월에서 최장 3년 7개월이었다. 2례를 제외하고는 모두 2년 내에 재발하였다. 재발 부위는 수술적 접근 후 창(Window)을 만든 부위의 인접한 피질골에서 대부분 관찰되었으며(11례), 2례는 수술적 접근을 한 골 시멘트의 심부(골수강측)에 발생하였다. 골 소파 술 후의 시멘트 충전술은 즉각적 안정성과 빠른 재활, 재발의 조기 발견의 유용성이 있다. 또한 이론적으로 주변의 남아있는 종양세포를 사멸시킬 수 있는 장점을 가지고 있다. 수술을 시행한 실제 임상 례에서 재발의 부위가 수술시 충분한 소파가 안된 부위(Window를 작게 내어 불충분한 소파가 된 부위, 주위 해부학적 구조상 건, 인대의 기시부나 종지부로 소파가 안된 부위)에서 대부분(85%)이 재발하였다. 결론: 거대 세포종의 치료에 있어서 골 소파술과 Burring 후 시멘트 충전술이 많이 사용되고 있다. 또한 소파술 후 보조적인 치료로서 페놀, $H_2O_2$를 이용한 화학적 소작, 냉동요법, 무수 알코올 등이 소개 되었지만, 아직 그 효과가 입증된 것이 없다. 많은 경우 주위의 인대나 건의 기시부나 종지부 또는 다른 해부학적 구조로 불충분한 창(Window)으로 인해, 수술적 접근을 한 부위의 골 소파술 및 Burring 이 불완전하게 되는 경향이 발생할 수 있다. 본 연구에서 재발의 부위는 대부분(85%)에서 불충분한 개창술이 된 부위에서 발생하였다. 즉, 중요한 해부학적 구조가 있더라도 충분한 개창술과 광범위한 소파와 Burring이 재발을 방지하는 가장 중요한 요소가 되리라 사료된다. 본 연구에서 거대세포종의 재발은 대부분 2년 이내에 발생하였다. 특히 이 기간에는 철저한 추적검사를 통하여 재발에 유의해야 한다.

• 소성∙가공
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• 제22권6호
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• pp.317-322
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• 2013

A radio frequency(R/F) switch connector is widely used in wireless devices such as mobile phone and navigator to check defects of the circuit board of product. The R/F switch connector shell plays a role in protecting the switch connector. Previously, this part was machined using a turning, which is time-consuming and has poor material utilization. Furthermore, the workpiece material of brass containing lead that has excellent machinability has environmentally regulated during recent years. The purpose of the current study was to develop the connector shell by forming through progressive dies including embossing, burring and forging process in order to achieve higher productivity and dimensional accuracy without tool failure. To accomplish this objective, a strip layout was designed and finite element (FE) analysis was performed for each step in the process. Try-out for the connector shell was conducted using progressive die design based on FE-analysis results. Dimensional accuracy of developed part was investigated by scanning electron microscopy. The result of the investigation for the dimensions of the formed connector shell showed that the required dimensional accuracy was satisfied. Moreover, productivity using the progressive die increased four times compared to previous machining process.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2019년도 춘계학술논문요약집
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• pp.361-362
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• 2019

• 소성∙가공
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• 제26권5호
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• pp.271-276
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• 2017

A tee is the most common pipefitting used to combine or divide fluid flow. Tees can connect pipes of different diameters or change the direction of a pipe run. To manufacture tee type of stainless steel pipe, combinations of punch piercing and burr forming have been widely used in the industry. However, such method is considerably time consuming with regard to performing empirical work necessary to attain process conditions to prevent upper end tearing of the tee product and meet target tee height. Numerous experiments have shown that the piercing profile is the main cause of defects mentioned above. Furthermore, the mold design is formed through trial and error according to pipe diameters and changes in requirements. Thus, the objective of this study was to perform piercing and burring process analysis via finite element analysis using DYNAFORM to resolve problems mentioned above. An optimization design method was used to determine the piercing punch profile. Three radii of the piercing punch (i.e., large, small, and joined radii) were selected as design variables to minimize thinning of a tee pipe. Based on results of correlation and multiple regression analyses, we developed a predictive approximation model to satisfy requirements for both thickness reduction and target height. The new piercing punch profile was then applied to actual tee forming using the developed prediction equation. Model results were found to be in good agreement with experimental results.

• Design & Manufacturing
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• 제6권2호
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• pp.17-23
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• 2012

In April 2010, the die and mould grand prix for university student was held in Osaka as a special event of Inter Mold Japan. The students from Korea, China, and Japan participated to demonstrate the design and manufacturing skill of die and mould. Based on the given product drawing of Test Work, progressive die should be designed and manufactured. Also, production of Test Work should be carried out. This study had been conducted to participate in the grand prix and to learn practical knowledge and experience from real die design and making. Test Work is made of SPCC and includes piercing, blanking, deep drawing and burring. From the analysis of product drawing, process planning and die design was carried out. Progressive die for Test Work was manufactured using CNC milling, grinding, wire-cutting and polishing. The production was successfully completed using mechanical press and product showed very good accuracy satisfying all dimensional tolerances.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2001년도 추계학술대회 논문집
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• pp.220-223
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• 2001

Until now, the clamp yoke of automobile has been largely manufactured by hot forging or burring process. Through the study, the precision cold forging process for clamp yoke has been analysed by using rigid-plastic finite element analysis code, DEFORM-3D. It has shown various results of the FEM simulation. An engineer should select the proper process considering the amount of product.

• Biomolecules & Therapeutics
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• 제9권1호
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• pp.51-54
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• 2001

Bufonis Venenum is a toad venom and its main components are bufadienolides, namely resibufogenin, bufalin and cinobufagin. The desensitizing effect of Bufonis Venenum is useful for the treatment of the premature ejaculation in Chinese medicine. But, minor components of Bufonis Venenum cause problems such as topical burring, pain, and erectile dysfunction. To clarify and eliminate the components responsible for these side effects, we prepared two extracts of Bufonis Venenum with either 70% ethanol or ethylacetate and tested their pharmacological effects. The extract of Bufonis Venenum with 70% ethanol produced pain response in rat hind paw, and exhibited contraction of rabbit corpus cavernosal muscle in vitro. On the other hand, the ethylacetate extract did not cause pain and smooth muscle contraction. The desensitizing effect of the ethylacetate extract was similar to that of the 70% ethanol extract. In conclusion, these results show that the extract of Bufonis Venenum with ethylacetate does not have the components causing side effects and deserve further study for therapeutic potential in premature ejaculation in men.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 추계학술대회 논문집
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• pp.228-229
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• 2007

As one way of weight saving of the vehicle, 1-piece typed lower control arm has been developed using high strength hot rolled steel sheet. In order to overcome the edge splitting problem during edge flanging or burring process, HER (hole expansion ratio) value of steel sheet was primarily considered. The strength grade of steel sheet and the shape were optimized utilizing Taguchi method.

• 한국광학회:학술대회논문집
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• 한국광학회 2008년도 하계학술발표회 논문집
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• pp.119-120
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• 2008

A HMD type multi-focus 3D display system is developed and proof about satisfaction of eye accommodation is tested. Four LEDs(Light Emitting Diode) and a DMD are used to generate four parallax images at single eye and any mechanical part is not included in this system. The multi-focus means the ability of monocular depth cue to various depth levels. By achieving multi-focus function, we developed a 3D display system for only one eye, which can satisfy the accommodation to displayed virtual objects within defined depth. We could achieve a result that focus adjustment is possible at 5 step depths in sequence within 2m depth for only one eye. Additionally, the change level of burring depending on the focusing depth is tested by captured photos and moving pictures of video camera and several subjects. And the HMD type multi-focus 3D display can be applied to a monocular 3D display and monocular AR 3D display.

• Journal of Korean Neurosurgical Society
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• 제65권1호
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• pp.107-113
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• 2022

Objective : To describe the surgical management and postoperative outcomes in infants with metopic synostosis. Methods : We conducted a 5 years retrospective chart review of patients who underwent surgical correction of metopic synostosis at two university hospitals in Egypt during the period between June 2014 and June 2019. The study is conducted to 18 children. The type of surgical procedures and postoperative outcomes were assessed in all patients. Results : Five cases (27.8%) underwent endoscopic-assisted suturectomy, 10 cases (55.6%) underwent craniofacial reconstruction, and three cases (16.6%) underwent open burring of the metopic ridge. Fifteen patients underwent one surgery and three patients (16.6%) who need second operation. Ten patients (55.6%) had class I Whitaker classification. Conclusion : Regardless of type of surgery, the outcomes of surgical correction of metopic synostosis are excellent with only a few patients require revision or develop major complications.