• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 1995년도 춘계학술대회논문집; 전남대학교, 19 May 1995
• /
• pp.190-195
• /
• 1995

초음파 세정기에 의한 세정 성능의 향상을 위한 연구로서, 세정조 내에서의 초음파 전파 현상을 이론적으로 밝히고, 수치해석에 의해 실제 상황의 음압 분포를 구하였으며, 실험에 의해 세정액 내 음압 분포를 확인하였다. 세정액 내의 음압 분포는 세정기 진동판으로부터의 거리에 따라 반파장 간격으로 극대점 또는 극소점이 반복된다. 이에 근거하여 세정 성능 향상 대책이 제시될 수 있게 되었다.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2009년도 하계학술대회 논문집
• /
• pp.162-163
• /
• 2009

본 연구에서는 초음파 진동자를 적용한 초극세사 자동 절단 시스템을 개발 하였다. 초극세사 자동 절단 시스템은 공진 주파수 28kHz를 가지는 초음파 진동자, 구동회로부, 원단 이송장치, 초음파 진동자 이송장치, 초극세사 원단과 에어실린더 사이의 정전기 발생을 방지하기 위한 정전기 제거장치, 구동모터, 및 절단 크기와 절단 속도 등을 조절하기 위한 전기제어 판넬로 구성하여 제작하였다. 또한, 개발한 절단 시스템을 이용하여 초극세사 클리너 시제품을 제작하여 절단면을 전자현미경으로 관찰하였고, 절단 시스템의 소음진동 특성을 평가하였다.

• 대한방사선기술학회지:방사선기술과학
• /
• 제41권3호
• /
• pp.241-247
• /
• 2018

The purpose of this study was to compare the ultrasound gel container washing methods for the sterilization of contaminants and to find the useful methods for the prevention of infection caused by the ultrasonic gel containers. In this experiment, a 250 mL ultrasonic gel container was used, and the ultrasonic gel used was a non-sterile gel (ECO GEL 99, SeungWon Medical, Korea). In order to evaluate the degree of contamination, new 250 mL 15 containers were divided into 5 groups to perform five types of washing by no treatment, washing with water, washing with soap, washing with bottle cleaner and high disinfection level washing. After the washing process, filled the gel container with gel and after 2 weeks, the number of colonies in the gel container was sampled repeatedly twice in the same ultrasonic laboratory and compared before and after washing. As a result of among the five cleaning methods used in this study, 87.2% and 88.9% of the soapy water washing (p = 0.028) and high level washing (p = 0.027) showed significant bacterial reduction rates, respectively. Our findings conclusively an ultrasonic gel container cleaning method for removing contaminants has been found to be an effective sterilization method at a low cost with a soapy water cleaning method. Therefore, it is expected that it will be helpful to prevent the infection caused by the ultrasonic gel container by suggesting the sterilization cleaning method that is practically useful in this study.

• 한국압력기기공학회 논문집
• /
• 제20권1호
• /
• pp.1-6
• /
• 2024

Crud is a corrosion deposit that forms in equipments and piping of nuclear reactor's primary systems. When crud circulates through the reactor's primary system coolant and adheres to the surface of the nuclear fuel cladding tube, it can lead to the Axial Offset Anomaly (AOA) phenomenon. This occurrence is known to potentially reduce the output of a nuclear power plant or to necessitate an early shutdown. Consequently, worldwide nuclear power plants have employed ultrasonic cleaning methods since 2000 to mitigate crud deposition, ensuring stable operation and economic efficiency. This paper details the system configuration of ultrasonic nuclear fuel cleaning equipment, outlining the function of each component. The objective is to contribute to the local domestic production of ultrasonic nuclear fuel cleaning equipment. Additionally, the paper introduces a method for accurately measuring the weight of removed crud, a crucial factor in assessing cleaning effectiveness and providing input data for the BOA code used in core safety evaluations. Accurate measurement of highly radioactive filters containing crud is essential, and weighing them underwater is a common practice. However, the buoyancy effect during underwater weighing may lead to an overestimation of the collected crud's weight. To address this issue, the paper proposes a formula correcting for buoyancy errors, enhancing measurement accuracy. This improved weight measurement method, accounting for buoyancy effects in water, is expected to facilitate the quantitative assessment of filter weights generated during chemical decontamination and system operations in nuclear power plants.

• Journal of Power Electronics
• /
• 제17권5호
• /
• pp.1150-1159
• /
• 2017

Flexibility in the power control of ultrasonic transducers has remained a challenge for cleaning applications. This paper introduces a modification of the existing piezoelectric ceramic transducer (PCT) circuit to increase the range of operation through its impedance characteristics. The output power is controlled using the asymmetrical voltage-cancellation (AVC) method. Together with a phase-locked loop control, the switching frequency of the inverter is automatically adjusted to maintain a lagging phase angle under load-parameter variations during the cleaning process. With the proposed modification, the region of the zero-voltage switching (ZVS) operation is extended, which results in a wider range of output power control. A hardware prototype is constructed and the control algorithm is implemented using an STM32F4 microcontroller. Simulation and experimental results are provided to verify the proposed method for a 50-W PCT. The operating frequency and output power ranges under study are 37 - 41 kHz and 15.8 - 50 W, respectively.

• Journal of Periodontal and Implant Science
• /
• 제27권1호
• /
• pp.205-215
• /
• 1997

In periodontal regeneration treatment, access to the frucation area is very difficult. Thus complete removal of plaque, calculus and endotoxin is somewhat impossible. In this study, teeth that were extracted due to periodontal disease were used. The furcation area was treated with periodontal curette, ultrasonic scaler, roto bur and they observed using SEM. The result was follows 1. The group treatment with curette showed remaining plaque, the cementum existed in most of the surface and partial dentinal tubule orifice could be seen. 2. The group treatment with ultrasonic scaler showed less removalof plaque compared to curette and irregular surface could be seen. 3. The group treatment with roto bur showed cleaner surface and many dentinal tubule orifice could be seen compared to the curette and ultrasonic scaler groups. Thus when suing treatments such as bone grafting or guided tissue regeneration, it is considered that the furcation area should be treatment with Roto bur.

• 한국응용과학기술학회지
• /
• 제27권2호
• /
• pp.107-113
• /
• 2010

The object of this research is to conform of practicable possibility and recycling of producing junk after citrus fruits is processed. With extracting d-limonene oil that have 70~90% a component of oil out of junk citrus peel, making certain the about 12000ppm concentration of it. Limonene derived from citrus in jeju using conventional synthetic detergents can be replaced with the development of environmentally friendly natural detergent investigated the possibility. Mostly due to ocean dumping, disposal and cause environmental problems by recycling natural citrus cleaner alternative to the research conducted on the possibility. Cleaning efficiency with temperature did not affect the largest concentrations were able to identify the difference between cleaning efficiency. At least 10% of the d-limonene oil could be from the cleaning performance, increasing the concentration of the cleaning efficiency was increased in size. Ultrasonic is very high removal efficiency under the conditions shown in the cause of pure self-generated ultrasonic cleaning power as co-effects of d-limonene oil appears to chemical cleaning effect of ultrasonic cavitation occurs in the physical cleaning effect due to a combination of synergistic stability is maximized by low concentrations of d-limonene oil in a short time showed an excellent cleaning ability. Having the ability of cleaning at the same time, considering the side recycling in the junk citrus peels reflects possibility of basic materials utility eco-friendly in the skin soap, bath soap, cosmetics etc, through ability of exclusion a contaminant in based cleaning effect(EC) it can prospect substitution effect environmentally in the pre existence synthetic detergents.

• 한국안광학회지
• /
• 제18권2호
• /
• pp.107-115
• /
• 2013

목적: 본 연구에서는 눈 화장품인 아이라이너에 노출시킨 소프트 콘택트렌즈의 파라미터가 어떻게 변하는가를 알아보고, 세척방법을 달리하여 세척하였을 때의 세척효과와 렌즈 파라미터의 회복정도를 비교하고자 하였다. 방법: 서로 다른 재질로 제조된 3종류의 소프트 콘택트렌즈에 각각 1시간, 4시간 및 6시간 동안 아이라이너를 침착시킨 후 안경용 초음파 세척 및 손 세척을 시행하였으며, 세척 전후 렌즈의 가시광선 투과도, 직경 및 표면의 변화를 비교하였다. 결과: 소프트 콘택트렌즈의 가시광선 투과도는 아이라이너의 침착시간이 길어질수록 감소하였다. 렌즈의 표면을 관찰한 결과 아이라이너의 침착 양상은 렌즈재질의 물성에 따라 다르게 나타나 narafilcon A 재질 렌즈에서 가장 침착이 큼을 알 수 있었다. 렌즈 직경은 hilafilcon B 및 etafilcon A 재질 렌즈는 감소하였으나, narafilcon A재질 렌즈는 증가하는 것으로 나타났다. 이러한 아이라이너의 침착은 안경용 초음파 세척기를 이용한 세척보다는 다목적 용액을 이용한 손 세척 시 세척효율이 우수한 것으로 나타났으나 렌즈의 직경이나 가시광선 투과도, 렌즈표면 등 렌즈 파라미터가 원래 상태로 회복되는 데에는 한계가 있었다. 결론: 이상의 결과로 소프트렌즈를 착용한 상태에서 눈 화장 하는 것을 최소화하는 것이 옳으며, 반복적으로 눈 화장을 할 때에는 렌즈 파라미터의 변화를 고려한 착용시간의 단축이나 빠른 렌즈의 교체주기가 필요하다고 사료된다.

• 대한치과보철학회지
• /
• 제38권3호
• /
• pp.358-359
• /
• 2000

Statement of problem. Confusion about the relationship of surface characteristics of implant to osteoblast cell attachment. Purpose. This study attempted to bone cell attachment to the implant surface which was modified by heat. Material and methods. Commercially pure titanium grade 2, $4{\times}4mm$ sheet 40 pieces were treated for 10 minutes with ultrasonic cleaner with methylethyl ketone, ethanol, deionized distilled water, and half of the specimen 20 pieces were heat treated in $980^{\circ}C$ for 15 minutes. All 40 specimens were autoclaves. Total 6 dishes were prepared, 3 dishes were for control group, and the other 3 dishes were for heat treatment. In fourth day, cell account was done. Conculsion. The change of surface characterization by heat treatment could affect the cell attachment in the early stage however, the change of surface characterization would not be prolonged.

• 한국산업융합학회 논문집
• /
• 제27권2_2호
• /
• pp.389-395
• /
• 2024

The purpose of this study was to evaluate the effect of different washing solvents and washing methods on the flexural strength of 3D printed temporary resin. A bar(25 × 2 × 2 mm) was produced with a layer thickness of 50 ㎛ using an LCD-type 3D printer and divided into 15 groups(n = 10, each) according to washing solution(IPA; 99% isopropyl alcohol, TPM; 93% Tripropylene glycol monomethylether, ETL; Ethanol, TWC; Twin 3D Cleaner, and DNC; DIO navi Cleaner) and washing method(Dip; Dip washing, Ultra; Ultrasonic washing, and Auto; Automated washing). All groups were washed for 5 minutes, and post-cured for 5 minutes using a UV LED light curing machine. The Flexural strength was measured using a three-point bending test using a universal testing machine. For statistical analysis, one-way ANOVA, Tukey HSD post hoc test, Kruskal-Wallis test and post-hoc by Bonferroni-Dunn test(𝛼=.05) were performed depending on whether the normality test was satisfied. In all washing solvents except TPM and DNC, the Dip group showed the lowest flexural strength values, while the Auto group showed the highest flexural strength values except for DNC. Additionally, the washing solution showed completely different flexural strength values depending on the washing method.