• Restorative Dentistry and Endodontics
• /
• 제34권5호
• /
• pp.390-396
• /
• 2009

이 실험의 목적은 $EndoVac^{(R)}$과 $EndoActivator^{(R)}$를 이용한 근관세척시 근관 내 접종된 Enterococcus faecalis의 제거 효율을 기존의 irrigation needle을 이용한 방법과 비교 평가하고자 함이다. 발거된 70개의 단근치를 사용하였으며 .04 taper ProFile #40까지 근관형성 후 치아를 멸균하고 근관에 E. faecalis를 접종하고 배양하였다. 치아는 근관세척 방법에 따라 20개씩 3개의 실험군과 2개의 대조군으로 나누었다. 2.5% 치아염소산나트륨을 사용하여 근관세척 시행 후 일차 표본을 채취하였고, 다시 근관 내에 배양액을 채우고 24시간 동안 배양 후 이차 표본을 채취하였다. 표본은 colony forming units (CFU) 값을 얻기 위해 BHI agar plate에 배양하였다. 일차 표본 결과에서는 모든 실험치아 중 기존의 근관세척 방법을 이용한 하나의 근관에서 양성 배양을 보였다. 이차 표본 결과에서는 $EndoVac^{(R)}$ 실험군에서 가장 적은 양성 배양을 보였으며, 기존의 근관세척 방법과 비교시 통계적으로 유의한 차이를 보였다. 실험 결과에 따르면 $EndoVac^{(R)}$은 근관 내 접종된 E. faecalis의 제거에 있어 기존의 근관세척 방법보다 더 좋은 효율을 보였다.

• Journal of information and communication convergence engineering
• /
• 제5권2호
• /
• pp.164-170
• /
• 2007

In this paper, the new method alternating with the method for forming the symmetrical distribution of power and local dispersion in high bit-rate WDM system with optical phase conjugator (OPC) is proposed. The proposed method is carried by finding out the optimal values of OPC position offset and fiber dispersion offset. It is assumed to be that NRZ-formatted 24-channels of 40 Gbps are simultaneously propagated in WDM system with non zero - dispersion shifted fiber (NZ-DSF) of 1,000 km. It is confirmed that the compensation extents of overall WDM channels are more improved by applying the induced optimal values into WDM system than those in WDM system with the conventional mid-span spectral inversion (MSSI) technique, and the searching procedure of the optimal values makes little difference of performance if the optimal value of one parameter related with another parameter. And, it is confirmed that the flexible design of WDM system with OPC is possible by effectiviely using by these optimal values. Thus, it is expected that the proposed method alternate with the forming method of the symmetrical distributions of power and local dispersion.

• 대한간호학회지
• /
• 제35권2호
• /
• pp.225-238
• /
• 2005

Hwa-Byung(HB) has been categorized as a Korean culture-bound syndrome that is prevalent in married women of low socioeconomic status. Purpose: The Purpose of the study was to search for the essence of HB and a caring-healing process of HB. Then the research result discusses whether the Transpersonal Caring-Healing Model has been congruent with it. Method: Case examples resulted from in-depth telephone counseling over a period of time at the Women's Hot Line with a client who is a housewife with HB. The counseling content was analyzed through Giorgi's method of descriptive phenomenology. Result: The core meaning of the essence of HB was 'injustice'; and essential themes were 'lack of reciprocity', 'infidelity' 'suppressed aggression and powerlessness' and 'need for recognition'. The core meaning of the essence of the caring-healing process was 'caring-healing experience(maintaining a trust relationship)'; and essential themes were 'active listening', 'empathy' and 'forming a therapeutic relationship'. According to Watson, 'active listening', 'empathy' and 'forming a therapeutic relationship' were identified as intentionality, intersubjectivity and transpersonal. Conclusion: Transpersonal caring can release inner power and strength and help the person to gain a sense of inner harmony. Transpersonal caring is as important to healing as are conventional treatment approaches and even more powerful in the long run.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2001년도 추계학술대회 논문집
• /
• pp.166-169
• /
• 2001

22,000 Ton hydraulic press was developed using wire winding method. The hydraulic press consists of three piece of frame type. The outer layers of yoke-column frame and main cylinder linear were wound with piano wire(1mm${\times}$4mm) under controlled tension and the total length of wound wire was about 450Km. The developed hydraulic press is used for the forming of heat plate with ultra-large size. To obtain large force with relative small apparatus, high pressure of $1,500 Kgf/cm^2$ was supplied to main cylinder through pressure amplification by booster pump. Therefore sealing technique of main cylinder is so crucial that the seals were made of mitre ring type with super-elastic metal. The press total weight is about 150 tons, which is quite light and compact relative to that of conventional hydraulic press.

• Food Science and Biotechnology
• /
• 제18권4호
• /
• pp.889-894
• /
• 2009

Barley proteins are expected to have unique functional properties due to their high content of alcohol soluble protein, hordein. Since the barley proteins obtained by conventional isoelectric precipitation method cannot represent hordein fraction, barley proteins were fractionated to albumin, globulin, glutelin, and hordein with respect to extraction solvents. Functional properties and film-forming properties of solubility-fractionated barley proteins were investigated to explore their potential for human food ingredient and industrial usage. The 100 g of total barley protein comprised 5 g albumin, 23 g globulin, 45 g glutelin, and 27 g hordein. Water-binding capacities of barley protein isolates ranged from 140-183 mL water/100 g solid. Hordein showed the highest oil absorption capacity (136 mL oil/100 g), and glutelin showed the highest gelation property among the fractionated proteins. In general, the barley protein fractions formed brittle and weak films as indicated by low tensile strength (TS) and percent elongation at break (E) values. The salt-soluble globulin fraction produced film with the lowest TS value. Although films made from glutelin and hordein were dark-colored and had lower E values, they could be used as excellent barriers against water transmission.

• 한국주조공학회지
• /
• 제26권5호
• /
• pp.227-231
• /
• 2006

Liquid formability of bulk amorphous alloys is known to be very poor due to their high viscosity comparing with conventional metallic materials. It is important to have the fabricating technology of bulk amorphous alloys in order to make the components with complicated shape. Liquid formability includes the mold cavity filling ability and the hot tear(crack) resistance during solidification. A mold made of a commercial tool steel for the formability test was designed. Melting was performed by the arc melting furnace with melting capacity of 200 g in an argon atmosphere. Liquid formability and glass forming ability of Cu base and Ni base bulk amorphous alloys were measured and evaluated. Mold filling ability of Ni-Zr-Ti-Si-Sn alloy was better than that of Cu-Ni-Zr-Ti alloy, however the reverse is the hot tear resistance. Bulk amorphous alloy is very susceptible to crack if partial crystallization occurs during solidification. Crack resistance was thought to be closely related with the glass forming ability.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2000년도 춘계학술대회 논문집
• /
• pp.963-966
• /
• 2000

Plasma display panel (PDP) is a type of flat panel display utilizing the light emission that is produced by gas discharge. Barrier Ribs of PDP separating each sub-pixel prevents optical and electrical crosstalk from adjacent sub-pixels. Mold for forming barrier ribs has been newly researched to overcome the disadvantages of conventional manufacturing process such as screen printing, sand-blasting and photosensitive glass methods. Mold for PDP barrier ribs have stripes of micro grooves transferring stripes of glass-material wall. In this paper. Stripes of grooves of which width 48 um, depth 124um, pitch 274um was acquired by machining the material of WC with dicing saw blade. Maximum roughness of the bottom and sidewall of the grooves was respectively 120 nm, 287 nm. Maximum tilt angle caused by difference between upper-most width and lower-most width was 2$^{\circ}$. Maximum Radius of curvature of bottom was 7.75 ${\mu}{\textrm}{m}$. This results meets the specification for barrier ribs of 50 inch XGA PDP. Forming the glass paste will be followed by using mold in the near future.

• 한국정밀공학회지
• /
• 제19권3호
• /
• pp.152-159
• /
• 2002

SLA (Stereolithography Apparatus) it a process used to rapidly produce polymer components directly from a computer representation of the part. Though SLA is being recognized as an innovative technology, it still cannot be used to fully practical application since it lacks of dimensional accuracy compared to conventional process. If the shrinkage were perfectly uniform and no distortion took place, excellent part accuracy could still be achieved through and appropriate scaling factor when generating the build file. However, in certain geometries involving intersecting thick and thin sections, nonuniform retrain shrinkage becomes the engine of part distortion. In order to improve the part accuracy of SLA, this paper evaluates how largely each parameter of SLA contributes to the part accuracy and estimates the optimal set of parameter which minimizes the dimension error of the test part, "Slab (100mm$\times$100mm$\times$2mm)"and "scale bar"part. Three control parameters such as critical exposure, generation depth and fill cure depth are used.

• 한국표면공학회지
• /
• 제23권1호
• /
• pp.34-43
• /
• 1990

Al-Si piston alloys such as AlS10CuMg have been anodized to examine apossibility of forming a hard film aat relatively higher temperatures compard with those in conventional sulfuric acid processes. Three types of electrolytes have been employed in this study ; electrolyte A(15% H2SO4, $0^{\circ}C$), electrolyte B(12% H2SO4, 1% oxalic, $10^{\circ}C$), electrolyte C(tartaric acid 125g/L+oxalic 75g/L+aluminum sulfate 225g/L, $25^{\circ}C$). Hard anodisine process in electrolyte B at a current density of 1.54A/dm2 produced a harder film of VHN 396 at a relatibely low film forming voltage compared with those obtained in other electrolyte at equivalent current density. A liner relationship between hardness and abrasion resistance exists for Al-Si piston alloys. The hardness of anodized film decreasees with increasing silicon content in Al-Si alloys and also with bath temperature. The film hardeness of Na-modified alloy os higher than that of P-modified alloy due to its finer microstructre. The film on the silicon phase in Al-Si alloys is observed to be formed by lateral growth of oxide film nucleated at surroundings.

• Tribology and Lubricants
• /
• 제4권1호
• /
• pp.56-68
• /
• 1988

The wear resistance of P-bronze which is widely used as worm gear material was investigated. In order 1o study the effect of additional elements on the wear resistance of Pbronze, the applied load and sliding time were selected as variables, and SCM4, were used as against metal. The addition of Fe improve wear resistance, for it precipities hard Fe$_3$ P phase and the work hardening coefficients are lowered due to decreasing solubility of P. When Fe is added in conventional P-bronze, the alloy is rather sliding than forming wear debris by frictional force during wear test. Experimental results indicated that the wear mechanisms for P-bronze are mainly consisted of abrasive wear due to Beilby layer forming mechanism and adhesive wear due to thermally activated wear mechanism. Moreover, the weight loss is decreased in accordance with increasing load and time. However the rate of wear loss is decreased as the sliding time is increased.