• Korean Journal of Radiology
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• v.2 no.4
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• pp.204-209
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• 2001

Objective: To determine the feasibility of transcaval transjugular intrahepatic portosystemic shunt (TIPS) in patients with occluded previous TIPS. Materials and Methods: Between February 1996 and December 2000 we performed five transcaval TIPS procedures in four patients with recurrent gastric cardiac variceal bleeding. All four had occluded TIPS, which was between the hepatic and portal vein. The interval between initial TIPS placement and revisional procedures with transcaval TIPS varied between three and 31 months; one patient underwent transcaval TIPS twice, with a 31-month interval. After revision of the occluded shunt failed, direct cavoportal puncture at the retrohepatic segment of the IVC was attempted. Results: Transcaval TIPS placement was technically successful in all cases. In three, tractography revealed slight leakage of contrast materials into hepatic subcapsular or subdiaphragmatic pericaval space. There was no evidence of propagation of extravasated contrast materials through the retroperitoneal space or spillage into the peritoneal space. After the tract was dilated by a bare stent, no patient experienced trans-stent bleeding and no serious procedure-related complications occurred. After successful shunt creation, variceal bleeding ceased in all patients. Conclusion: Transcaval TIPS placement is an effective and safe alternative treatment in patients with occluded previous TIPS and no hepatic veins suitable for new TIPS.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.17 no.3
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• pp.1-17
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• 2022

This study studied the effect of the TIPS support project of the Ministry of SMEs and Startups on the entrepreneurship of TIPS start-ups. The Tips start-up company, which is the subject of the study, was selected for the TIPS support project, participated in all commercialization funds, incubation facilities, and capacity building programs, and was selected as a company that received private investment. One-on-one in-depth interviews were conducted for about eight weeks from January 14, 2022 to March 11, 2022. For this study, the TIPS support project was subdivided into four categories: commercialization funds, incubation facilities, capacity building programs, and private investment attraction, and entrepreneurship factors were classified into four categories: innovation, challenge spirit, leadership, and risk-taking. As a result of the in-depth interview, the influence of the TIPS support project on entrepreneurship factors was in the order of challenge spirit, innovation, risk-taking, and leadership. Specifically, it was found that commercialization funds influenced innovation and risk-taking, incubation facilities had a challenge spirit and risk-taking, competency-building programs had a challenge spirit and leadership, and attracting private investment had an influence on innovation and challenge spirit. The implications of this study are that the TIPS support project, a private investment-led technology start-up support program, was introduced in 2013 and as of the end of March 2022, and a report was prepared focusing on visible performance such as private investment performance and employment rate. However, through this study, by analyzing whether the TIPS support project contributed to the cultivation of entrepreneurship for TIPS start-ups, it was found that it had a positive influence not only on quantitative growth but also on qualitative growth.

• The Journal of Korean Medicine
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• v.23 no.4
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• pp.27-31
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• 2002

Background and Purpose: There has been little study about the quality of acupuncture needle tips. In order to ensure safe acupuncture treatment, high quality of needle tips is essential. Therefore, we investigated the current condition of the tips of the acupuncture needles on the market. Methods: We selected needles made by 6 companies in Korea, one company each in Japan, the USA and China, and observed the tip of each needle using a scanning electron microscope. Results and Discussion: We found that needles had several defects such as scratch marks on the surface, metallic scuff, lumps and irregularities of the needle tips, stubbed or malformed tips, tips of point off-center, and peeled off coated tips. There were more faulty ones than good ones. Further, better-designed study with a bigger sample size is warranted.

• Transactions on Electrical and Electronic Materials
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• v.14 no.2
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• pp.82-85
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• 2013

This paper introduces 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS pentacene) doped liquid crystal (LC) alignment properties on a rubbed polyimide (PI) layer as a function of the doping concentration of TIPS pentacene. Pretilt angles, photomicrographs, and electro-optical properties of TIPS pentacene doped LCs were comparable to those of pure LCs. However, TIPS pentacene in a LC medium supported twisted nematic-liquid crystal displays (TN-LCDs) to improve electro-optical properties. The threshold voltages observed in the TN cells decreased as the TIPS pentacene concentration increased. In addition, suitable response times were observed in TN cells.

• Fashion & Textile Research Journal
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• v.21 no.3
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• pp.318-325
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• 2019

This study analyzes current self-nail tips and nail-tip satisfaction. The study method selected from 3 domestic and 3 overseas companies analyzed current self-nail tips based on brand recognition and sales rate. A questionnaire was conducted on 261 adult women in their 20s and 50s about the satisfaction of nail care and self-nail tips. The results are as follows. As a result to analyze the current nail tips, there were products that did not contain the type of nail tip or the composition and ingredients of the glue. An online survey of the sizes of the current nail tips indicated differences in the sizing system method and that the presented sizes are different. The response rate was the highest for the survey results on why self-nail tips were preferred for respondents who prefer self-nail tips because the price was cheap. The reason why they did not prefer self-nail tips was that the degree of completeness was lower and the fitness was not good. In addition, it showed a high response rate in that the adhesive strength was poor and the size did not fit the nails. Therefore, it is necessary to develop a size for nail types by ergonomic design and develop a self-nail tip that can reduce nail damage.

• Journal of the Korean Vacuum Society
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• v.17 no.5
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• pp.435-441
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• 2008

In this paper, we investigated the electrical properties of triisopropylsilyl (TIPS) pentacene organic thin-film transistor (OTFT) depending on solvent type. We spin coated TIPS pentacene by using chlorobenzene, p-xylene, chloroform, and toluene as solvents. Fabricated OTFT with chlorobenzene shows field-effect mobility of $1.0{\times}10^{-2}cm^2/V{\cdot}s$, on/off ratio of $4.3{\times}10^3$ and threshold voltage of 5.5 V. In contrast, with chloroform, the mobility is $5.8{\times}10^{-7}cm^2/V{\cdot}s$, on/off ratio of $1.1{\times}10^2$ and threshold voltage of 1.7 V. Moreover we measured the grain size of each TIPS pentacene solvent by atomic force microscopy (AFM). From these results, it can be concluded that a solvent with higher boiling point results in better electrical characteristics due to large grain size and high crystallinity of TIPS pentacene layer. In this paper TIPS pentacene with chlorobenzene shows the best electrical properties.

• Membrane Journal
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• v.24 no.2
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• pp.158-166
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• 2014

In this research, microporous and bicontinuous poly vinylidene fluoride(PVDF) hollow fiber membranes were prepared via hybrid process of the thermally induced phase separation (TIPS) and stretching method. The mechanism of the membrane preparation is based on liquid-liquid phase separation. The final membranes have characteristic structures which have both bicontinuous and fibrillar morphology by applying the stretching method. They showed quite different structure when compared with the spherulitic or nodular structure from S/L TIPS and bicontinuous structure from L/L TIPS. At first, PVDF hollow fiber precursors were prepared via TIPS method using various kind of diluent mixtures. We used gamma-butyrolacton, dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP) as diluents. We could make hollow fiber membranes which had porous outer surface or dense outer surface by controling the parameters such as cooling conditions, PVDF concentration and the ratio of diluent mixtures. Finally, these hollow fiber were stretched at room temperature and diluents were extracted by ethanol. Effects of the stretching ratio on the membrane morphology were investigated using scanning electron microscope (SEM), and its effects on water flux, porosity, pore size, roughness and tensile strength were examined.

• Membrane Journal
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• v.34 no.4
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• pp.216-223
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• 2024

In comparison to commonly employed polypropylene (PP) material, polymethylpentene (PMP) exhibits low surface energy and reduced crystallinity, allowing fabrication of asymmetric membranes with a dense skin layer. However, its higher melting point poses significant challenges with respect to polymer processability. In this work, we utilized the N-TIPS method, which combines the advantages of non-solvent induced phase separation (NIPS) and thermally induced phase separation (TIPS), to fabricate PMP membranes. Cyclohexane was employed as the solvent for preparing the PMP dope solution, while water, ethanol (EtOH), and isopropanol (IPA) were used as nonsolvents. When cyclohexane-immiscible water was used as the nonsolvent, the resulting membrane exhibited TIPS morphology with unifrom pore structure but lacked suface uniformity. In contrast, when cyclohexane-miscible alcohols (EtOH, IPA) were employed, the membranes displayed NIPS morphology with a dense skin layer with higher mechanical strength. Furthermore, the effect of polyethylene glycol (PEG) as a pore forming agent was investigated to better control the surface pore size.

• Journal of Welding and Joining
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• v.22 no.4
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• pp.35-42
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• 2004

Contact tips are required to have a higher resistance to wear and thus to have an extended life time under the advanced GMAW welding process. Several requirements have been specified and employed by domestic industries for selecting their tips for such a purpose. However no attempt has been made to justify their requirements based on the experimental data of wear resistance or life time of contact tips. In this study, five different contact tips with three different compositions were employed for actual GMA welding up to 4 hours and were evaluated their wear resistance by measuring in every one hour the area of enlarged hole at the exit side. Experimental results clearly showed that the Cr-containing tips strengthened by precipitation hardening have much better resistance to wear than those made by work hardening. It was further noticed that Cr is an excellent alloying element for improving the wear resistance of contact tips only when it is in an properly aged condition. Initial hardness may play some role in the early stage of wear but not in the later stage of welding because the microstructure of tip changes significantly by the prolonged exposure to welding arc heat. Based on these results, critical review has been made on the current requirements employed by domestic industries. Of importance is that a new guideline has been confirmed to be more reasonable.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.7
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• pp.96-101
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• 2013

In this paper we analyzed the effects of polystyrene(PS) blended in TIPS-pentacene on the performance of OTFTs. With the various molecular weight and the content of PS the performance of TIPS-pentacene OTFTs was examined and the proper molecular weight and the content were extracted for the best results. With the molecular weight of 9,580 and 0.3 wt% of PS OTFTs produced the mobility of $1.0{\pm}0.19cm^2/V{\cdot}sec$, the subthreshold slope $0.22{\pm}0.05$ V/dec, the threshold voltage $-1.19{\pm}1.21$ V, the current on/of ratio $7.12{\pm}2.09{\times}10^6$. Additionally the suitable substrate temperature for ink jet printing of the blended TIPS-pentacene OTFTs was also extracted and it was $46^{\circ}C$.