• Journal of the Korean Society for Precision Engineering
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• v.20 no.9
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• pp.40-46
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• 2003

Synchronizing errors between the spindle motor and the z-axis motor directly influences the cutting characteristics and the thread quality in tapping, because the tapping process is accomplished by synchronizing the movement of the z-axis with the revolutionary spindle motion. Generally synchronizing errors are decided by tile parameters of the servo system and commanded velocity. The excessive synchronizing errors which are induced by the parameter mismatch and high cutting velocity can cause tap breakage due to the abrupt increase of cutting torque or damage the thread accuracy by overcutting the already cut threads. In this paper, the influences of the synchronizing errors on the tapping characteristics in the ultra high-speed tapping will be described and a minimum level of synchronizing errors necessary to maintain the quality of the cut thread will be presented.

• Journal of the Korean Society of Industry Convergence
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• v.10 no.4
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• pp.195-200
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• 2007

These days, various and complex threads are developed, so it is necessary to develop the cutting a thread sensors for checking a cut thread in severe environment and it is very important to evaluate the quality of the cutting a thread sensors. The analysis of variance(ANOVA) method is very useful method on the quality evaluation field. In this study, the quality is evaluated by one way layout ANOVA method with the surface roughness data. The experiment is carried out by 3 sensors and the result show that the sensors have the good quality in precision.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2006.05a
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• pp.341-344
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• 2006

Finite element analysis and verification experiments were performed in order to find cause of defects such as folding and improper radius around the root area of the thread rolled stud bolts. Thread rolling experiments under several conditions were also carried out to understand the effect of process parameters, such as the rotation speed of the dies and the hardness of the work pieces, on the product quality. Folding defects at the top of thread are attributed to the higher hardness of the work piece and higher rotation speed of the rolling die. It was also found that the radius of screw mainly determined by the radius of the die.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2002.05a
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• pp.133-137
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• 2002

This paper summarizes the results of a numerical study conducted to analyze the determination of optimum blank diameter on material flow and thread profile for Spindle Screw in external thread rolling. Initial blank diameter affect a quality of Spindle Screw in thread rolling process. Therefore, it is very important to determine the optimum blank diameter in thread rolling process. In order to determine the optimum blank diameter, this paper suggest the calculating method of initial blank diameter considering real shape of tooth. The finite element code DEFORM is applied to analyze the metal flow of tooth. then the analytical results are verified by experiment of thread rolling for Spindle Screw.

• Journal of Physiology & Pathology in Korean Medicine
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• v.31 no.5
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• pp.284-293
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• 2017

Thread embedding therapy is used increasingly for various disease including neck pain. However, the evidence of thread embedding therapy on neck pain and the assessment of their methodology are still limited. This study aimed to investigate the clinical research methodology using thread embedding therapy on neck pain. Thread embedding therapy is used increasingly for various disease including neck pain. However, the evidence of thread embedding therapy on neck pain and the assessment of their methodology are still limited. This study aimed to investigate the clinical research methodology using thread embedding therapy on neck pain. Total 31 studies were included in analysis. Thread embedding therapy usually was used once a week(32.3%), once per 10days(29.0%), once per two weeks (25.8%). The most common concurrent treatment used with thread embedding therapy was Chinese medicine. Among acupuncture points, EX-B2 (61.3%) was most commonly used, followed by GV14(45.2%), GB20(29.0%), GB21(22.6%). For control group, acupuncture were most commonly used(58.1%). All studies reported that the effect of thread embedding therapy was more effective compared to control group. and 11 studies reported side effects. Only 13 studies(41.9%) reported the appropriate randomization method, and the mean Jadad score of included studies was 1.52. Previous clinical trials included in this study showed the effect of thread embedding therapy for neck pain. However, the quality of the studies was not high. Further rigorous clinical trials are need to assess the effect of thread embedding therapy.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.29 no.1
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• pp.103-112
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• 2016

Objective : Thread embedding acupuncture has become popular as a minimally invasive treatment for facial wrinkles and laxity. However, there is little published clinical practice guidelines about disinfection, sterilization and aseptic technique for thread embedding acupuncture. This study is to introducing a specific guidelines about disinfection, sterilization and aseptic technique for thread embedding acupuncture.Method : We reviewed internal regulations and guidelines about hospital infection, and Traditional Korean medicine doctors, nurses, and director of central supply room discussed in depth and established a regulation of disinfection, sterilization and aseptic technique for thread embedding acupuncture.Result : The regulation of disinfection, sterilization and aseptic technique for thread embedding acupuncture consisted of ① management of supplies, ② guidelines of disinfection, sterilization, and reuse, ③ aseptic technique for thread embedding acupuncture.Conclusion : Microbial management is an essential element of medical care and quality. Traditional Korean medicine doctors will care for disinfection, sterilization, and this should not neglect to comply with the procedures and guidelines in the medical field as well as to understand the aseptic techniques.

• Korean Journal of Acupuncture
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• v.38 no.3
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• pp.122-132
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• 2021

Objectives : This systematic review aims to assess the effectiveness of thread embedding therapy on animal model for rheumatoid arthritis. Methods : Search was conducted in the Cochrane library, MEDLINE (PubMed), EMBASE, the Chinese National Knowledge Infrastructure, Wan-Fang Database, Technology Journal Database, the Korean Studies Information Service System, the Oriental Medicine Advanced Searching Integrated System, the Research Information Sharing Service, the National Digital Science Library, the Korean Traditional Knowledge Portal and the Korea Citation Index. Data were extracted concerning animal model, intervention and rheumatoid arthritis indicator by two independent reviewers. Reporting quality was also evaluated by the ARRIVE (Animal Research: Reporting In Vivo Experiments) guidelines 2.0. Results : One thousand thirty six studies were primarily selected. After screening, 10 studies met the inclusion criteria. 1 study was published 2005, 1 study was published 2010, 1 study was published 2012, 1 study was published 2015, 2 studies were published 2016, 3 studies were published 2017, 1 study was published 2018. The most frequently used acupoints were ST36 and BL23, and were used with an average frequency of 11.8 days. All of these thread embedding therapy studies were effective on behavioral, morphological, immunohistological and hematological indicators to treat of rheumatoid arthritis model. Conclusions : These results demonstrated the effectiveness of thread embedding therapy and suggested the putative mechanism. However, considering the small number of included studies, low reporting quality and differences in study design, further studies with rigorous designs and high reporting quality need to be conducted.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.18 no.5
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• pp.514-520
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• 2009

Titanium is one of the most attractive materials due to their superior properties of high specific strength and excellent corrosion resistance. The applications in aerospace and medical industries demand machining process more frequently to obtain more precise products. Machining of titanium is faced with strong challenges such as increased component complexity i.e. airframe components manufacturing processes. The machining cost on titanium have traditionally demanded high cutting tool consumable cost and slow machining cycle times. Similarly, the high wear of the cutting tools restricts the cutting process capabilities. Titanium screws applied to fasten parts In the several corrosion environment. In the thread cutting of titanium alloys, the key point for successful work is to select proper cutting methods and tool materials. This study suggests a guidance fur selecting the cutting methods and the tool materials to improve thread quality and productivity. Some experiments investigate surface roughnesses, cutting forces and tool wear with change of various cutting parameters including tool materials, cutting methods, cutting speed. As the results, the P10 type insert tip was assured of the best for thread cutting of Ti-6Al-4V titanium alloy. Also the initial depth of infeed was desirable to use the value below 0.5mm as the uniform cutting area method is applied.

• The Journal of Advanced Prosthodontics
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• v.7 no.2
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• pp.115-121
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• 2015

PURPOSE. This study aimed to evaluate the effect of implant thread depth on primary stability in low density bone. MATERIALS AND METHODS. The insertion torque was measured by inserting Ti implants with different thread depths into solid rigid polyurethane blocks (Sawbones) with three different bone densities ($0.16g/cm^3$, $0.24g/cm^3$, and $0.32g/cm^3$). The insertion torque value was evaluated with a surgical engine. The static compressive strength was measured with a universal testing machine (UTM) and the Ti implants were aligned at $30^{\circ}$ against the loading direction of the UTM. After the static compressive strength test, the Ti implants were analyzed with a Measurescope. RESULTS. The Ti implants with deeper thread depth showed statistically higher mean insertion torque values (P<.001). Groups A and group B had similar maximum static compressive strengths, as did groups C and D (P>.05). After the static compressive strength, the thread shape of the Ti implants with deeper thread depth did not show any breakage but did show deformation of the implant body and abutment. CONCLUSION. The implants with deeper thread depth had higher mean insertion torque values but not lower compressive strength. The deep threads had a mechanical stability. Implants with deeper thread depth may increase the primary stability in areas of poor quality bone without decreasing mechanical strength.

• Advances in concrete construction
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• v.16 no.2
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• pp.91-96
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• 2023

The present work provides a new solution to both the correct execution and quality control of straight thread couplers for reinforcing bars under monotonic loading conditions. A random survey on already constructed couplers together with a new mechanical model, adjusted with an experimental campaign, led us to present this new procedure in reinforced concrete construction. Formulation and methodology for a correct placement of straight thread couplers is presented.