• Title/Summary/Keyword: Contact point

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Effect of proton concentration in TEOS to improve durability of hydrophilic and high light transmittance properties of nanosilica coating (친수 및 높은 광투과 기능을 함유한 나노실리카 코팅액의 내구성 향상을 위한 수소이온 농도에 따른 TEOS의 반응 연구)

  • Lee, Soo;Chan, Sung Il;Hwang, Heon
    • Journal of the Korean Applied Science and Technology
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    • v.33 no.3
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    • pp.483-491
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    • 2016
  • Even though the antifogging property of nanosilica coated glass surface is highly increased due to the hydrophilic hydroxyl groups on nanosilica surface, the durability of this property on outdoor glass was diminished rapidly after rain washing. In addition the topology of nanosilica coated glass surface plays very important roles to control an light transmittance or antireflection property. To improve these coating durability and characteristics a hydrophilic nanosilica coating on glass was prepared by coating with 1.5 wt% of nanosilica (Ludox) suspension in the presence of hydrolyzed tetraethylorthosilicate (TEOS). The optimum hydrolysis condition of TEOS in acidic or basic aqueous solution was also examined by contact angle measurement. The final transparent hydrophilic coating layer coated with nanosilica-TEOS in acidic condition (pH=4) showed much improved durability of hydrophilic surface as well as higher visible light transmittance than original uncoated glass by 2 % point.

The vertical orbicularis oculi muscle turn-over procedure for the correction of paralytic ectropion of the lower eyelid

  • Azuma, Ryuichi;Aoki, Shimpo;Aizawa, Tetsushi;Kuwabara, Masahiro;Kiyosawa, Tomoharu
    • Archives of Plastic Surgery
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    • v.45 no.2
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    • pp.135-139
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    • 2018
  • Background Static reconstruction surgery that tightens the tension of the inferior tarsus, thereby raising the lax lower eyelid, is a common treatment for paralytic ectropion of the lower eyelid. We present one such operative procedure, in which an orbicularis oculi muscle flap was used. Methods The surgical technique involves partial resection of the tarsus and the skin, as well as a superior-based orbicularis oculi muscle flap that is sutured to the firm tissue present on the Whitnall tubercle. The muscle flap is approximately 7 mm in width and 15 mm in length, with a superior pedicle that is attached to the tarsus at the medial point of the resected tarsus. The procedure results in contact between the ocular surface and the lower eyelid. Results The procedure was performed in 11 patients with lower eyelid ectropion due to facial paralysis. Ten cases showed a favorable outcome following surgery, with stable results seen over an average follow-up period of 4.5 years. In one case, recurrence of ectropion was observed 2 months after surgery due to an insufficient correction, and the patient required repeat surgery. Conclusions The orbicularis oculi muscle flap was an effective means of suspension and was able to maintain long-term traction tension. This procedure can therefore be considered a favorable treatment option for lower eyelid ectropion due to facial paralysis.

A Study on Fashion Toys Appearing in Modern Fashion (현대패션에 나타난 패션 토이에 관한 고찰)

  • Kim, Youngmi;Geum, Keysook
    • Journal of the Korean Society of Costume
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    • v.66 no.6
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    • pp.79-94
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    • 2016
  • The purpose of this study is to explore the process of how modern fashion establishes new consumption cultures by analyzing the different types of fashion toys that have appeared in modern fashion, and identifying inherent meanings of the said toys. The range of this study was limited to four collections (New York, London, Milano, Paris) from 2000 to 2015. In addition to these collections, advertisement campaign and cooperative examples as well as examples of fashion toys that appeared in public interest activities and collections were included. The selected materials were classified into different types of fashion toy usage. From the results of analyzing fashion toys appearing in modern fashion, the four following characteristics. After analyzing the use of fashion toys in modern fashion, four characteristics were found. First, fashion toys were found to be a means to maximize the visual effects of the collection stage. Second, fashion toys utilized as a fashion object were key elements in transforming neo-pop into modern fashion, and constructing high fashion. Third, the fact that people's fashion and fashion toys share contemporary fashion means that customers are shared through the integration of diverse media. This leads to creation of new benefits. Fourth, fashion toys are meaningful because the products reflect contemporary culture, and extend the scope of fashion and art, as it can be considered fashion as well as art. In conclusion, fashion toys were meaningful in that high fashion broke from conservative values, and swiftly introduced contemporary culture codes. It derived a point of effective contact to present a new way of consumption and extended the scope of fashion.

Damage mechanism of particle impact in a ${Al_2}}O_3}-TiO_2$plasma coated soda-lime glass (${Al_2}}O_3}-TiO_2$ 플라즈마 코팅된 유리의 입자충격에 의한 손상기구)

  • Suh, Chang-Min;Lee, Moon-Hwan;Hong, Dea-Yeong
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.22 no.3
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    • pp.529-539
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    • 1998
  • A quantitative study of impact damage of ${Al_2}}O_3}-TiO_2$ plasma coated soda-lime glasses was carried out and compared with that of the uncoated smooth glass specimen. The shape of cracks by the impact of steel ball was observed by stereo-microscope and the decrease of the bending strength due to the impact of steel ball was measured through the 4-point bending test. At the low velocity, cone cracks were occurred. As the impact velocity increases, initial lateral cracks were propagated on the slanting surface of a cone crack, and radial cracks were generated at the crushed site. When the impact velocity of steel ball exceeds the critical velocity, the contact site of specimen was crushed due to plastic deformation and then radial and lateral cracks were largely grown. Crack length of coated specimens was smaller than that of uncoated smooth specimen due to the effect of coating layer on the substrate surface. According to impact velocity, the bending strength of coated specimens had no significant difference, compared with that of the uncoated smooth specimen. But this represents that the bending strength of coated specimens was increased, considering the effect of sand blasting damage which was performed to increase the adhesion force of coating layer.

Enhanced compatibility and initial stability of Ti6Al4V alloy orthodontic miniscrews subjected to anodization, cyclic precalcification, and heat treatment

  • Oh, Eun-Ju;Nguyen, Thuy-Duong T.;Lee, Seung-Youp;Jeon, Young-Mi;Bae, Tae-Sung;Kim, Jong-Gee
    • The korean journal of orthodontics
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    • v.44 no.5
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    • pp.246-253
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    • 2014
  • Objective: To evaluate the bioactivity, and the biomechanical and bone-regenerative properties of Ti6Al4V miniscrews subjected to anodization, cyclic precalcification, and heat treatment (APH treatment) and their potential clinical use. Methods: The surfaces of Ti6Al4V alloys were modified by APH treatment. Bioactivity was assessed after immersion in simulated body fluid for 3 days. The hydrophilicity and the roughness of APH-treated surfaces were compared with those of untreated (UT) and anodized and heat-treated (AH) samples. For in vivo tests, 32 miniscrews (16 UT and 16 APH) were inserted into 16 Wistar rats, one UT and one APH-treated miniscrew in either tibia. The miniscrews were extracted after 3 and 6 weeks and their osseointegration (n = 8 for each time point and group) was investigated by surface and histological analyses and removal torque measurements. Results: APH treatment formed a dense surface array of nanotubular TiO2 layer covered with a compact apatite-like film. APH-treated samples showed better bioactivity and biocompatibility compared with UT and AH samples. In vivo, APH-treated miniscrews showed higher removal torque and bone-to-implant contact than did UT miniscrews, after both 3 and 6 weeks (p < 0.05). Also, early deposition of densely mineralized bone around APH-treated miniscrews was observed, implying good bonding to the treated surface. Conclusions: APH treatment enhanced the bioactivity, and the biomechanical and bone regenerative properties of the Ti6Al4V alloy miniscrews. The enhanced initial stability afforded should be valuable in orthodontic applications.

A Qualitative Study on Social Work Applicants' Impression Management Tactics in Job Interviews (사회복지 지원자의 채용면접 인상관리전략에 관한 질적 연구)

  • Jang, Yeon-Jin;Jeong, Sun-Wuk
    • Korean Journal of Social Welfare
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    • v.60 no.1
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    • pp.77-102
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    • 2008
  • The purpose of this study is to know what impression management(IM) tactics social work applicants use in their job interviews and what relation between their IM tactics and interviewers' evaluation exists. To accomplish this purpose, we reviewed the precedent researches about IM and conducted a qualitative study with the applicants in a community welfare center which adopted open approach in recruitment process. We analyzed the applicants' IM tactics through observing video-taped interview sessions and reviewing interviewers' rating paper. The results showed that the social work applicants mainly used self-promotion tactic for emphasizing their strengths and justification tactics for expressing their weaknesses. Some applicants often used fit-with-organization and other-enhancement belonged to ingratiation tactics. According to interviewers' rating results, the applicants with deep eye contact, calm attitude or smiling face gave a good impression to the interviewers. In the final discussion, an applicant who adopted diverse verbal and non-verbal tactics and expressed her point clearly was perceived attractive by the interviewers and accepted as the best choice. Based on this qualitative analysis, we have made several practical suggestions for social work applicants, social work researchers and social work organizations.

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Three-Dimensional Finite element analysis of Canine and Carnassial for Observation of Dog Bite forces (개(犬)의 교합력 관찰을 위한 견치와 열육치의 3차원 유한요소 분석)

  • Park, Yu-Jin;Kim, Chi-Young;Choi, Sung-Min
    • Journal of Technologic Dentistry
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    • v.41 no.4
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    • pp.295-301
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    • 2019
  • Purpose: This study is for the prosthesis of dogs. Observe the occlusal relation between the dog's canine and carnassial teeth. The strength and the direction of the occlusal by 3D FEM analysis. Methods: The mandibular canine and carnassial of dogs were tested. The dog's skull was contact point confirmed by dental CAD. The skull of the dog was 3D modeled by CT. The 3D model was analyzed by ABAQUS. Opening and closing movement has been a force of 100N, 200N, 300N, 500N, 1000N, 1,500N. The peak von Mises stress distribution was confirmed. Results: As occlusal force increased, stress appeared to 1.34 MPa, 3.32 MPa, 5.00 MPa, 6.19 MPa, 5.58 MPa, 5.47 MPa in left canine. and Stress was seen at 2.10 MPa, 3.08 MPa, 3.89 MPa, 5.50 MPa, 7.04 MPa, 7.18 MPa in the right canine. Stress appeared at 2.41 MPa, 3.53 MPa, 5.15 MPa, 7.28 MPa, 31.26 MPa, 67.22 MPa in the left carnassial. and Stress was seen at 1.57 MPa, 2.96 MPa, 3.76 MPa, 6.01 MPa, 20.94 MPa, 64.38 MPa in the right carnassial. Conclusion: Peak von Mises stress values were found at the peak of the canine, the buccal of the central cusp of the carnassial, and the occlusal surface of the distal cusp.

Classification of Food Safety Crises and Standard Setting for Crisis Level in Food Industry (식품산업체가 겪는 위기의 분류와 위기 수준 판단)

  • Kim, Jong-Gyu;Kim, Joong-Soon
    • Journal of Environmental Health Sciences
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    • v.41 no.2
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    • pp.133-145
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    • 2015
  • Objectives: Food safety has become one of the major public-concerning issues in Korea. In order to set guidelines to create manuals for the response to a food safety crisis by food industry, this paper classified food safety crises and suggested techniques to determine crisis level. Methods: This study clarified common terminologies and definitions including in food safety crises. It reviewed various food safety crises and described characteristics, types, and states of crises. Results: The results of this study suggested that a food safety crisis implied a situation in which hazards/risk spreading in the food supply chain was widely described, causing strong public concern followed by a socioeconomic impact, and therefore, requiring the implementation of a prompt and full response regarding the situation. In terms of seeking response plans, food safety crises might be classified according to the penalties resulting from violations of laws and regulations, causative substances, stages of the food supply chain, and first contact point for incidents. The crisis level for a food safety crisis could be classified according to its severity parameters. The guideline matrix was divided into four major stages: Blue/guarded, Yellow/elevated, Orange/high, and Red/severe. This study also suggested several methods for determining the crisis level, such as the simple judgement method, scoring methods using a check-list and a weighted check-list. Conclusion: The severity of related parameters might be of great importance in understanding a crisis and determining response options/challenges for crisis levels.

A Study on WB(Water-Bubble) Based Highly Secure Flexible Network Section (WB(Water-Bubble) 기반의 강한 보안성을 갖는 탄력적 네트워크 구간에 관한 연구)

  • Seo, Woo-Seok
    • The Journal of the Korea institute of electronic communication sciences
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    • v.12 no.5
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    • pp.737-746
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    • 2017
  • In 2017, amid changes in the security market such as integrated security (IS) and convergence security (CS), a variety of security paradigms in terms of operation and management have been suggested. Rather than changing existing network infrastructure and bringing about fluid, multi-dimensional changes, these solutions and technologies focus entire security capacity on a primary protection, leading to network infrastructure suffering from unexpected inherent violations and problems in a continued manner. Therefore, it is time to propose and develop a flexible network section that can protect from attacks of similar pattern and concentrated traffic attacks by applying a new concept of WB (Water-Bubble) to network infrastructure and analyzing on the basis of experiment and installation. Methodology of the WB-based highly secure flexible network section proposed in this study is expected to provide materials for studies on how to achieve network section security taking into account three major limitations and security standards: fluidity, unpredictability, and non-area scalability by contact point ratio, by changing a network area predicted to be the final target of attack into resonant network section (area) with flexible area changes.

Study on Backfire for a Two-Stroke Hydrogen Fueled Free-Piston Engine with Loop Scavenging (루프소기방식을 갖는 2행정 프리피스톤 수소기관의 역화에 관한 연구)

  • Cho, Kwan-Yeon;Byun, Chang-Hee;Back, Dae-Ha;Lee, Jong-Tae
    • Transactions of the Korean hydrogen and new energy society
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    • v.21 no.6
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    • pp.487-492
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    • 2010
  • For developing a two-stroke free-piston hydrogen engine with high efficiency and low emission, determination of the scavenging type is one of the most important factor. In this research, backfire characteristics for loop scavenging were analyzed with the number of piston crevice volume and piston expansion speed. Rapid Compression Expansion Machine, RCEM was used for combustion research of the free piston $H_2$ engine in the experiment. As the results, it was shown that although backfire occurring in a loop scavenging type can be partially controled by a complete exhaust of burned gas, possibility of backfire basically exist due to the structure which piston crevice volumes contact with fresh mixture in a scavenging port. However, a loop scavenging may be considered as combustion chamber of a free piston $H_2$ engine from the point of view that backfire does not occur nearby lean equivalence ratio obtained high thermal efficiency. It was also analyzed that an advances of backfire occurrence timing with increase of the fuel-air equivalence ratio were due to promotion of flame propagation into piston crevice volumes by decrease of the quenching distance.