• 대한관절경학회:학술대회논문집
• /
• 2006.11a
• /
• pp.89-89
• /
• 2006

• The korean journal of orthodontics
• /
• v.32 no.2 s.91
• /
• pp.143-153
• /
• 2002

The bonded orthodontic retainer constructed from composite and multistrand orthodontic wire provides an esthetic and efficient system for maintained retention. This study was designed to measure shear bond strength of bonded retainers and to suggest a optimal combination of a multistrand wire and bonding method used when bonded retainer was fabricated. 160 sound maxillary and mandibular premolars were used for 80 test samples. After Uniformizing bonding area, length of wire, and thickness of composite, multistrand wire was bonded to fabricated a bonded retainer by direct or indirect bonding method. Shear bond strength and extension length of each sample were measured by a universal testing machine. The results of this study were as follows : 1. In vitro shear bond testing found 6-stranded, 0.0155 inch wires to have the largest shear bond strength and 3-stranded, 0.0195 inch wires to have the least shear bond strength. But, These difference was not statistically significant(p<0.05). 2. In vitro extension testing found 3-stranded, 0.0155 inch wires to have the largest extension length and 3-stranded, 0.0195 inch wires to have the least extension length(p<0.05). The larger diameter wire was used, the larger extension length was shown. But, the strand of wire is not related to the extension length of wire. 3. In comparison with direct bonding method, larger shear bond strength and extension length was shown in indirect bonding method(p<0.05).

• Clinics in Shoulder and Elbow
• /
• v.13 no.1
• /
• pp.40-46
• /
• 2010

Purpose: The aim of this study was to evaluate the usefulness of arthroscopic Bony Bankart repair using a One Anchor Double Fixation Technique. Materials and Method: Seventeen patients with a Bony Bankart lesion were treated using the One Anchor Double Fixation Technique (OADF Technique). There were 13 males and 4 females. The average age was 24 years (range 17-42). The average follow-up period was 22.3 months. One 3.0 mm suture anchor with doubly loaded sutures was inserted into the glenoid rim. One suture strand was passed the around the small bony fragment and tied first. Another suture strand was passed through the capsule and tied over the bony fragment. The result was measured using Rowe's evaluation index & KSS score. The glenoid defect & bony fragment were measured by 3D-CT scan. Results: Rowe's evaluation index on the final follow-up showed an overall improvement from an average of 54 (range, 23-71) to 83.4 (range 71-90). Of the 17 cases, 13 were excellent, 3 were good, and 1 was fair. KSS scores showed improvement from an average of 71 (range 49-82) to 92.5 (range 82-94). There were no cases where pain continued to the final follow-up, and no cases being re-dislocated during the follow-up period. For six cases, we confirmed the bony healing of the bony Bankart lesion by CT. Conclusion: Bony Bankart lesion repair using this new method achieves excellent clinical results with low recurrence rates and is considered another choice for bony Bankart lesions.

• The Academic Congress of Korean Shoulder and Elbow Society
• /
• 2009.03a
• /
• pp.186-186
• /
• 2009

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
• /
• 2003.10a
• /
• pp.45-48
• /
• 2003

Ramp-rate limitation is a serious obstacle for successful operation of fast charging and discharging magnet Ramp-rate limitation is hard to expect or fully investigate due to its electric and thermo-hydraulics couplings. In this paper, the simplest case of ramp-rate limitation is investigated with two-strand superconducting cable model considering transient heat transfer The simulation results are compared with the experimental results.

• The Journal of Korean Academy of Prosthodontics
• /
• v.47 no.2
• /
• pp.191-198
• /
• 2009

Statement of problem: Ceramics have been important materials for the restoration of teeth. The demands of patients for tooth-colored restorations and the availability of various dental ceramics has driven the increased use of new types of dental ceramic materials. Improved physical properties of theses materials have expanded its use even in posterior crowns and fixed partial dentures. However, ceramic still has limitation such as low loading capability. This is critical for long-span bridge, because bridge is more subject to tensile force. Purpose: The wire reinforced ceramic was designed to increase the fracture resistance of ceramic restoration. The purpose of this study was to evaluate the fracture resistance of wire reinforced ceramic. Material and methods: Heat pressed ceramic(ingot No.200 : IPS Empress 2, Ivoclar Vivadent, Liechtenstein) and Ni-Cr wire(Alfa Aesar, Johnson Matthey Company, USA) of 0.41 mm diameter were used in this study. Five groups of twelve uniform sized ceramic specimens(width 4 mm, thickness 2 mm, length 15 mm) were fabricated. Each group had different wire arrangement. Wireless ceramic was used as control group. The experimental groups were divided according to wire number and position. One, two and three strands of wires were positioned on the longitudinal axis of specimen. In another experimental group, three strands of wires positioned on the longitudinal axis and five strands of wires positioned on the transverse axis. Three-point bending test was done with universal testing machine(Z020, Zwick, Germany) to compare the flexural modulus, flexural strength, strain at fracture and fracture toughness of each group. Fractured ceramic specimens were cross-sectioned with caborundum disc and grinded with sandpaper to observe interface between ceramic and Ni-Cr wire. The interface between ceramic and Ni-Cr wire was analyzed with scanning electron microscope(JSM-6360, JEOL, Japan) under platinum coating. Results: The results obtained were as follows: 1. The average and standard deviation in flexural modulus, flexural strength and fracture toughness showed no statistical differences between control and experimental groups. However, strain was significantly increased in wire inserted ceramics(P<.001). 2. Control group showed wedge fracture aspects across specimen, while experimental groups showed cracks across specimen. 3. Scanning electron microscopic image of cross-sectioned and longitudinally-sectioned specimens showed no gap at the interface between ceramic and Ni-Cr wire. Conclusion: The results of this study showed that wire inserted ceramics have a high strain characteristic. However, wire inserted ceramics was not enough to use at posterior area of mouth in relation to flexural modulus and flexural strength. Therefore, we need further studies.

• Korean Journal of Food Science and Technology
• /
• v.25 no.1
• /
• pp.46-51
• /
• 1993

The inactivating effect of iron(II)-ascorbate complex (Fe-Asc) on various phages was previously reported. This paper describes the molecular target in the phage virion attacked by Fe-Asc. The effect of Fe-Asc on protein was investigated with bovine serum albumin and the structural protein of phage J1. There were no differences in the SDS-polyacrylamide gel electrophoresis (patterns of these two proteins when either they were treated) with Fe-Asc or not. Also, there were no changes in the amino acid composition and ultraviolet spectrum of the proteins. The effects of Fe-Asc on DNA was investigated with pUC18 DNA, M13mpB DNA and ${\lambda}$ DNA as well as DNA from phage J1. Fe-Asc caused initially nicking of the subsequently form of pUC18 DNA to yield the open circular form and then subsequently the linear form. Strand breaks were also confirmed with M13mp8 DNA and ${\lambda}$ DNA as well as J1 DNA. The results indicate that the strand breaks in phage DNA could be responsible for the inactivation of phages by Fe-Asc.

• Journal of the Korea Society of Computer and Information
• /
• v.15 no.12
• /
• pp.209-216
• /
• 2010

Optical Temperature Distribution Sensor Measurement System uses fiber optic sensors itself for temperature measurement is a system which can be measured the Installed surrounding entire temperature as a thousand points by laying a single strand of fiber optic. If there are a lot of measuring points in the distribution Measurement, the cost of each measuring point can be reduced the cost level of existing sensors and at the same time this has the advantage of connecting all sensors as one or two strands of fiber. Generally Optical Fiber is used for communication but Optical Fiber itself can be used for sensor and it has the characteristic of sensor function which can be measured Temperature in the at least each one meter distance. By using these characteristics each sensor and the number of Connection Lines can be reduced. In this paper, we implement a real time temperature monitoring system, which is easy to manage and control for data storage, data management, data storage using a computer and which has the functions of monitoring and correction according to Real-time temperature changes using historical temperature data.

• Electronics and Telecommunications Trends
• /
• v.19 no.6 s.90
• /
• pp.1-12
• /
• 2004

1960년대에 발명된 광섬유를 이용한 광통신기술은 1980년대 이래 빠르게 보급되었다. 특히 인터넷 트래픽이 폭발적으로 증가하기 시작한 1990년대 후반에 파장 분할 다중화(WDM) 기술이 상용화 되었으며 이 기술은 불과 수년 사이에 하나의 물리적인 광섬유 한 가닥을 통해 독립적인 수백 채널의 신호를 전송할 수 있는 수준에 이르렀다. 이에 더하여 ETDM 기술의 발전으로 채널 당 10Gbps 내지 40Gbps에 이르는 신호를 전송할 수 있게 되어 광섬유 선로 당 전송 용량은 테라급이 가능해졌다. 전송 용량의 빠른 확장과 과장된 수요 예측은 결국 공급 과잉을 초래하여 최근 수 년간 광전송 분야 시장이 침체된바 있다. 그러나 매년 약 두 배씩 꾸준히 증가하는 트래픽 덕에 최근에는 과잉 공급 분이 소진되어 가고 있으며 새로 시장이 활성화되고 있다. 새 시장에서는 종래의 점대점 방식을 넘어 메시형의 WDM 광 네트워크가 등장할 것이며 이에 따른 다양한 요소 기술을 요구하게 될 것이다. 본 고에서는 광전송 기술의 핵심 분야인 광 트랜스폰더 기술, 광 증폭기 기술, 그리고 광 네트워크 기술을 중심으로 현황과 발전전망을 알아본다.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2003.02a
• /
• pp.215-220
• /
• 2003

인간 게놈 프로젝트가 지속적으로 진행됨에 따라 계속적으로 대량의 유전체 정보가 밝혀지고 있으며, 이미 밝혀진 유전체의 염기서열을 바탕으로 다양한 생물의 전체 유전자의 기능을 효율적으로 해석하는 기술의 개발이 요구되고 있다. 식물 게놈 프로젝트 또한 식량확보라는 단순하면서도 전략적인 차원에서 가장 절실히 요구되는 기본 과학기술 연구분야이다. 게놈(genome)은 유전자(gene)와 염색체(chromosome)의 합성어로 한 생물체가 지닌 모든 유전 정보의 집합체이고, 동종의 재결합 DNA 분자를 포함하는 동일 세포의 개체를 클론(clone)이라 하며, 클론의 집합체를 콜로니(Colony)라 한다 생물체의 모든 유전정보를 가진 게놈은 핵산(nucleotide acid)이라 불리는 염기로 이루어져 있으며, 이들은 서로 상보적인 쌍을 이루어 두 가닥으로 형성되어 있다. 이를 한 쌍의 base pair라 한다. (중략)