• Nuclear Engineering and Technology
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• 제48권1호
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• pp.189-199
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• 2016

Fast neutrons with a broad energy spectrum, with which it is possible to evaluate nuclear data for various research fields such as medical applications and the development of fusion reactors, can be generated by irradiating proton beams on target materials such as beryllium. To generate short-pulse proton beam, we adopted a deflector and slit system. In a simple deflector with slit system, most of the proton beam is blocked by the slit, especially when the beam pulse width is short. Therefore, the available beam current is very low, which results in low neutron flux. In this study, we proposed beam modulation using a buncher cavity to increase the available beam current. The ideal field pattern for the buncher cavity is sawtooth. To make the field pattern similar to a sawtooth waveform, a multiharmonic buncher was adopted. The design process for the multiharmonic buncher includes a beam dynamics calculation and three-dimensional electromagnetic simulation. In addition to the system design for pulsed proton generation, a test bench with a microwave ion source is under preparation to test the performance of the system. The design study results concerning the pulsed proton beam generation and the test bench preparation with some preliminary test results are presented in this paper.

• Journal of Oral Medicine and Pain
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• 제19권2호
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• pp.137-151
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• 1994

In order to evaluate objectively the anxiety level in dental treatment, the author used Biotrainer(BF-120R), one of the skin temperature biofeedback apparatus, to examine 68 dental outpatients on their digital skin temperature change due to routine consecutive dental procedures(oral examination, anesthetic injection, cavity preparation, fissure sealing, polishing). The subjective anxiety level change was also evaluated by visual analog scale. The obtained results were as follows : 1. The skin temperature decreased through consecutive procedures and the temperature in each procedure decreased until 60sec, and then increased on 120sec. 2. The temperature changes in Preparation and Injection were greater than those in other procedures. 3. Generally, male exhibited more change of skin temperature in all procedures than female. 4. Type II, continuously decreasing after procedure, occupied the most in all patients and yhad the lowest beseline temperature. 5. The anxiety level of before-procedure was higher than that of after-procedure and the levels in Injection and Preparation were higher than in other procedures.

• Restorative Dentistry and Endodontics
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• 제27권3호
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• pp.257-269
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• 2002

Objective : The purpose of this study was to evaluate the resin infiltration into dentin of one-bottle adhesive systems and self-etching primer bonded to Class V cavities using confocal laser scanning microscope(CLSM). Material and Methods : Forty Class V cavities were prepared from freshly extracted caries-free Human teeth. These teeth were divided into two groups based on the presence of cervical abrasion: Group I, cervical abrasion : Group II, wedge-shaped cavity preparation. Resin-dentin interfaces were produced with two one-bottle dentin bonding systems-ONE COAT BOND(OCB; Coltene$^R$) and Syntac$^R$SPrint$^{TM}$(SS; VIVADENT)-, one self-etching priming system-CLEARFIL$^{TM}$ SE BOND (SB : KURARAY)- and one multi-step dentin bonding system-Scotchbond$^{TM}$Multi-Purpose (SBMP, 3M Dental Products)-as control according to manufacturers' instructions. Cavities were restored with Spectrum$^{R}$(Dentsply). Specimens were immersed in saline for 24 hours and sectioned longitudinally with a low-speed diamond disc. The resin-dentin interfaces were microscopically observed using CLSM. The quality of resin-infiltrated dentin layers were evaluated by five dentists using 0~4 scale. Results : Confocal laser scanning microscopal investigations using primer labeled with rhodamine B showed that the penetration of the primer occurred along the cavity margins. Statistical analysis using one-way ANOVA followed by Duncan's Multiple Range test revealed that the primer penetration of the group 2(wedge-shaped cavity preparation) was more effective than group 1(cervical abrasion) and that of the gingival interfaces was more effective than the occlusal interfaces. In the one-bottle dentin bonding systems, the resin penetration score of OCB was compatible to SBMP, but those of SS and self-etching priming system, SB were lower than SBMP.

• 생약학회지
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• 제21권2호
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• pp.163-172
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• 1990

These studies were conducted to investigate the effects of Tongkwan-San water extract on analgesic, sedatative, anti-inflammatory, blood pressure and vasodilating actions, the relaxing action of isolated ileums and actions on the contact dermatitis induced by picryl chloride and on the leakage of the dye into the peritoneal cavity. The results of these studies were summarized as follows: The analgesic effect of Tongkwan-San was noted. The prolongation of anesthetic time of Tongkwan-San was recognized. Spontaneous motilities of isolated ileum of mice were strongly suppressed by Tongkwan-San. It inhibited the contractions of isolated ileum of mice induced by acetylcholine and barium chloride and the contraction of isolated ileum of guinea-pig induced by histamine. Inhibition of the contact dermatitis induced by picryl chloride was recognized. Anti-inflammatory effects in the paw edema induced by histamine and dextran were significantly shown. The leakage of dye into the peritoneal cavity in mice was significantly inhibited. Hypotensive and vasodilating action due to vascular smooth muscle relaxation were noted in rats and rabbits.

• Restorative Dentistry and Endodontics
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• 제10권1호
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• pp.161-168
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• 1984

The purpose of this study was to examine the effect of heat generated by rotating bur on the dental hard tissue in vitro. Freshly extracted molar teeth with normal appearance from early 20's male were collected and experimental teeth were divided into 4 groups and the teeth in each group were prepared class I cavity with different clinical procedures as follows. The four methods were. I. 20,000rpm without coolant II. 20,000rpm with coolant III. 500,000rpm without coolant IV. 500,000rpm with coolant Five teeth were reserved intact as a control group. These teeth were longitudinally split into two parts by means of chisel after class I cavity preparation. In a control group 5 parts were boiled in water for 20 minutes and the other 5 specimens were not boiled. All specimens were immersed in 2% methylene blue dye solution and the image of dye penetration was examined and photographed under stereomicroscope. Followings were the results obtained through the study. 1. In control group, dye penetration of the unboiled specimens was increased than with the boiled group. 2. The specimens prepared cavity without coolant showed decreased dye penetration than with the coolant group. 3. 20,000rpm without coolant group showed the least dye penetration. 4. 500,000rpm with coolant group showed similar level of dye penetration to the unboiled specimens from the control group.

• Nuclear Engineering and Technology
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• 제51권3호
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• pp.877-883
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• 2019

Superconducting multi-spoke cavities are outstanding alternative choice for acceleration of heavy ions in medium velocity regimes. Based on the scheme of China ADS, several researches on the superconducting double-spoke cavities were done and two prototype cavities have been developed. In this paper, the RF design, the mechanical design and fabrication considerations of the bare cavity will be described in detail. After Buffered Chemical Polishing and High Pressure Rinsing, one of the prototype cavities was installed into the Vertical Test Stand for high gradient RF testing at 4.2 K. The measurement results of the quality factor as a function of the accelerating field and the maximum surface field will be presented. An accelerating gradient of more than 15 MV/m is achieved during the test, with maximum surface electric field of 58 MV/m, and maximum surface magnetic field of 117 mT.

• 대한소아치과학회지
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• 제32권4호
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• pp.595-603
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• 2005

와동 형성시 박테리아에 감염된 상아질이나 법랑질을 완전히 제거하지 않는 것은 수복학적 측면에서 볼 때 잠재적 문제점이 된다. 수복물 하방에서의 박테리아의 활동에 의해 술후 과민반응, 치수의 염증. 이차 우식 등이 진행될 수 있다. 와동세척제는 와동 형성 후 잔존 박테리아의 제거를 위해 효과적으로 사용될 수 있지만 상아세관에 잔유물을 남겨 상아질 결합제와 치질간의 긴밀한 결합을 방해하여 미세누출을 증가시키고 결합강도를 약화시킬 가능성이 있다. 본 연구는 2% 클로르헥시딘을 함유하는 와동 세척제인 $Consepsis^{(R)}$(Ultradent, USA)가 $Adper^{TM}$ $Scotchbond^{TM}$ Multi-Purpose(3M ESPE, USA), $Adper^{TM}$ Single Bond(3M ESPE, USA), $Adper^{TM}$ $Prompt^{TM}$ $L-Pop^{TM}$(3M ESPE, USA)의 결합에 미치는 영향을 평가하기 위하여 발거된 제 3대구치 120개를 이용하여 $Consepsis^{(R)}$ 와동 세척제를 사용한 군과 사용하지 않은 군으로 나누어 전단결합강토 측정과 수복물 변연에 나타나는 미세누출 정도를 색소 침투 평가 방법으로 분석함으로써 다음과 같은 결론을 얻었다. 1. $Consepsis^{(R)}$ 와동 세척제의 사용 유무는 $Adper^{TM}$ $Scotchbond^{TM}$ Multi-Purpose, $Adper^{TM}$ Single Bond, $Adper^{TM}$ $Prompt^{TM}$ L-Pop의 전단결합강토에 있어 통계학적으로 유의한 차이를 보이지 않았다(p>0.05). 2. $Consepsis^{(R)}$와동 세척제의 사용 유무는 $Adper^{TM}$ $Scotchbond^{TM}$ Multi-Purpose, $Adper^{TM}$ Single Bond, $Adper^{TM}$ $L-Pop^{TM}$ $L-Pop^{TM}$의 미세누출 양상에 있어 통계학적으로 유의한 차이를 보이지 않았다(p>0.05).

• Restorative Dentistry and Endodontics
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• 제39권4호
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• pp.276-281
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• 2014

Objectives: The purpose of this study was to compare the cutting efficiency of a newly developed microprojection tip and a diamond-coated tip under two different engine powers. Materials and Methods: The apical 3 mm of each root was resected, and root-end preparation was performed with upward and downward pressure using one of the ultrasonic tips, KIS-1D (Obtura Spartan) or JT-5B (B&L Biotech Ltd.). The ultrasonic engine was set to power-1 or -4. Forty teeth were randomly divided into four groups: K1 (KIS-1D / Power-1), J1 (JT-5B / Power-1), K4 (KIS-1D / Power-4), and J4 (JT-5B / Power-4). The total time required for root-end preparation was recorded. All teeth were resected and the apical parts were evaluated for the number and length of cracks using a confocal scanning micrscope. The size of the root-end cavity and the width of the remaining dentin were recorded. The data were statistically analyzed using two-way analysis of variance and a Mann-Whitney test. Results: There was no significant difference in the time required between the instrument groups, but the power-4 groups showed reduced preparation time for both instrument groups (p < 0.05). The K4 and J4 groups with a power-4 showed a significantly higher crack formation and a longer crack irrespective of the instruments. There was no significant difference in the remaining dentin thickness or any of the parameters after preparation. Conclusions: Ultrasonic tips with microprojections would be an option to substitute for the conventional ultrasonic tips with a diamond coating with the same clinical efficiency.

• 대한치과의사협회지
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• 제50권7호
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• pp.384-393
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• 2012

Successful treatment of a badly broken down tooth with pulpal disease depends not only on good endodontic therapy, but also on good prosthetic reconstruction of the tooth after endodontic therapy is completed. The ideal treatment of endodontically treated teeth has been widely and controversially discussed. Endocrown is a restorative option for endodontically treated teeth. Endocrown design incorporates the core and short post into the crown as a single restoration. The preparation of endocrown consists of a circular equigingival butt-joint margin and central retention cavity of the entire pulp chamber instead of employing intraradicular posts. This design significantly increases the surface area of the preparation available for cementation. It is particularly useful in young patient teeth for long-term provisional restoration and in teeth with short clinical crowns. This technique represents a promising and conservative method for the treatment of endodontically treated teeth that require long-term protection and stability. Endocrown can be considered as a feasible alternative to full crowns or composite overlays for the restoration of non vital teeth.

• 대한후두음성언어의학회지
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• 제20권1호
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• pp.31-35
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• 2009

Transnasal Esophagoscopy allows the upper aerodigestive tract, from the nasal cavity to the gastric cardia to be examined in the outpatients department. It is well tolerated by patient with topical anesthesia alone and no sedation or patient preparation is required. The technique is easily learned and performed in the otolaryngologist and highly cost efficient. It is a useful tool for accurate diagnosis and can be used in a variety of office-based procedures.