• 대한치과교정학회지
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• 제27권4호
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• pp.633-641
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• 1997

성장 또는 치료로 인한 악안면골의 변화는 두부 방사선을 중첩 함으로써 판단할 수 있다. 중첩에 대한 평가는 중첩방법에 따라 변화되므로 좀더 정확한 중첩 방법을 선택하는 것은 치료 효과에 대한 분석이나 성장 변화에 대한 평가를 정확히하는 선결 요건이 될것이다. 3년 정도의 비교적 짧은 성장기간을 가진 11세 전후의 여자 환자 19명을 대상으로, 가장 널리쓰이는 중첩 방법인 Nasion-Sells line중첩과 Bjork가 주장하는 Anteirior cranial base (ACB)중첩을 비교하여 다음과 같은 결론을 얻었다. 1 Nasion-Sells line중첩과 ACB중첩은 중첩오차(registration error)의 크기가 거의 같아서 reliability에 있어서 큰차이가 없는 것으로 나타났다 2. 검사자간 차이(interobserver difference)에 있어서 Nasion-Sells line중첩은 7개의 측정 항목 모두에서 두 검사자간에 차이가 없었으나 ACB중첩은 7개의 측정 항목중 4개의 측정 항목에서 두 검사자간 유의성 있는 차이가 나타났다. 3. 중첩방법의 차이 (intermethod difference)에 있어서 Nasion-Sella line중첩으로 측정한 계 측치와 ACB 중첩으로 측정한 계측치가 유의성있게 차이가 나지 않았다.

• 한국기계가공학회지
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• 제21권9호
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• pp.78-84
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• 2022

An air circuit breaker (ACB) is an electrical protection device that interrupts abnormal fault currents that result from overloads or short circuits in a low-voltage power distribution line. The ACB consists of a main circuit part for current flow, mechanism part for the opening and closing operation of movable conductors, and arc-extinguishing part for arc extinction during the breaking operation. The driving mechanism of the ACB is a spring energy charging type. The faster the contact opening speed of the movable conductors during the opening process, the better the breaking performance. However, there is a disadvantage that the durability of mechanism decreases in inverse proportion to the use of a spring capable of accumulating high energy to configure the breaking speed faster. Therefore, to simultaneously satisfy the breaking performance and mechanical endurance of the ACB, its driving mechanism must be optimized. In this study, a dynamic model of the ACB was developed using the MDO(Mechanism Dynamics Option) module of CREO, which is widely used in multibody dynamics analysis. To improve the opening velocity, the Taguchi design method was applied to optimize the design parameters of an ACB with many linkages. In addition, to evaluate the improvement in the operating characteristics, the simulation and experimental results were compared with the MDO model and improved prototype sample, respectively.

• Journal of Ginseng Research
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• 제44권1호
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• pp.123-134
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• 2020

Background: The lepidopteran Asiatic corn borer (ACB), Ostrinia furnacalis (Guenee), has caused huge economic losses throughout the Asian-Western Pacific region. Usually, chemical pesticides are used for the control, but excessive use of pesticides has caused great harm. Therefore, the inartificial ecotypic pesticides to ACB are extremely essential. In our previous study, we found that panaxadiol saponins (PDS) can effectively reduce the harm of ACB by causing antifeedant activity. Therefore, it is necessary to reveal the biological molecular changes in ACB and the functionary mechanism of PDS. Methods: We analyzed the global transcription of ACB with different PDS concentration treatment (5 mg/mL, 10 mg/mL, and 25 mg/mL) by high-throughput sequencing and de novo transcriptome assembly method. Results: PDS treatment could cause the changes of many gene expressions which regulate its signal pathways. The genes in peroxisome proliferator-activated receptor (PPAR) signaling pathway were significantly downregulated, and then, the downstream fatty acid degradation pathway had also been greatly affected. Conclusion: Through this experiment, we hypothesized that the occurrence of antifeedant action of ACB is because the PDS brought about the downregulation of FATP and FABP, the key regulators in the PPAR, and the downregulation of FATP and FABP exerts further effects on the expression of SCD-1, ACBP, LPL, SCP-X, and ACO, which leads to the disorder of PPAR signaling pathway and the fatty acid degradation pathway. Not only that, PDS treatment leads to enzyme activity decrease by inhibiting the expression of genes associated with catalytic activity, such as cytochrome P450 and other similar genes.

• 전기학회논문지
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• 제58권7호
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• pp.1321-1328
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• 2009

In this paper, an electromagnetic force driving actuator (EMFA) and three-link mechanism are proposed as a driving mechanism and connection device for low voltage air circuit breaker (ACB). As the result of dynamic characteristic analysis, the actuator and link mechanism are designed from the simulation and manufactured. The magneitc field of the EMFA is analyzed using the finite element method (FEM). The dynamic characteristic analysis with calculation of the circuit equation and kinetical equation is performed by the time difference method (TDM). Also, the result of the analysis is verified through the experiment of the fabrication model. In this paper, the EMFA size is smaller than the actuator for high voltage circuit breaker. Thus, the dynamic characteristic is analyzed with end-winding inductance that is calculated by the same method which is applied on the circle type end-winding of motors. The designed model for 1600 ampere-frame ACB and the three-link mechanism for connecting contact part with actuating part are manufactured. It is confirmed that the three-link mechanism is possible for improving the circuit breaker efficiency and reducing the size of the EMFA. It is proved that the improved 2-D analysis is more accurate than established method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 춘계학술대회 논문집 에너지변화시스템부문
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• pp.97-99
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• 2009

In this paper, a new type of electromagnetic actuator, an electro magnetic force driving actuator (EMFA) is developed and analyzed, applicable to air circuit breaker (ACB). Transient analysis is performed in order to obtain the dynamic characteristics of the EMFA. The distribution of static magnetic flux is obtained using the finite element method (FEM). The coupled problems of electrics and mechanics governing equations are solved using the time difference method (TDM). Also according to interception rate of each contactor, investigation about load condition of contactor spring is conducted, applied it to three-link system. And comparison about dynamic characteristics of three-link simulation and experiment data are performed.

• 지구물리와물리탐사
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• 제6권4호
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• pp.180-186
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• 2003

수평(HCP)및 수직동일면(VCP)배열을 사용하는 다중 주파수 소형루프 전자탐사 자료의 1차원 역산 프로그램을 개발하였다. 역산방법은 ACB 최소자승법을 사용하였으며, Jacobian 행렬을 해석적으로 계산하였다. 간단한 1차원 모델에 대한 이론자료를 계산하고, 동상 및 이상성분 자료를 사용하여 역산을 수행하였다. 역산 결과 동상 및 이상성분을 모두 사용할 경우 가장 정확하게 각 층의 전기전도도 및 심도를 추정하는 것으로 나타났다.

• 센서학회지
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• 제27권5호
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• pp.335-339
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• 2018

The optical characteristics of a terahertz (THz) antenna-coupled bolometer (ACB) detector were evaluated using a pulsed quantum cascade laser (QCL) and radiation blackbody sources. We investigated a method for measuring the responsivity and noise-equivalent power (NEP) of the THz detector using two different types of light sources. When using a QCL source with a frequency of 3 THz, the average responsivity of 24 devices was $1.44{\times}10^3V/W$ and the average NEP of those devices was $3.33{\times}10^{-9}W/{\surd}Hz$. The average responsivity and NEP as measured by blackbody source were $1.79{\times}10^5V/W$ and $6.51{\times}10^{-11}W/{\surd}Hz$, respectively, with the measured values varying depending on the light source. This was because the output power of each light source was different, with the laser source being driven by a pulse type wave and the blackbody source being driven by a continuous wave. The power input to the THz sensor was also different. Futhermore, the responsivity and NEP values measured using band pass filter (BPF) were similar to those measured when using only THz windows. It was found that ACB sensor responds normally in the THz region to both the laser and the blackbody source, and the method was confirmed to effectively evaluate the characteristics of the THz sensor.

• Journal of Electrical Engineering and Technology
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• 제8권3호
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• pp.595-602
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• 2013

An air circuit breaker (ACB) with novel double-breaker contact and permanent magnet actuator (PMA) is presented. Three-dimensional (3-D) finite element method (FEM) is employed to compute the electro-dynamic repulsion forces, including the Holm force and Lorentz force, which are acting on the static and movable contacts. The electro-dynamic repulsion forces of different contact pieces are computed, illustrating there is an optimal number of contact pieces for the ACB being studied. The electro-dynamic repulsion force of each contact, which varies from the outer position to the inner position, is also computed. Finally, the contacts of the double-breaker are manufactured according to the analyzed results to validate the simulations.

• 대한임상검사과학회지
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• 제49권4호
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• pp.427-434
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• 2017

Acinetobacter calcoaceticus-baumannii (Acb) complex에 속한 종들은 빈번하게 병원감염 및 기회감염을 일으킨다. 또한 다제내성인 경우가 많아 이 균들의 감염증 치료를 위한 항균제 선택이 매우 제한적이다. 본 연구에서는 ciprofloxacin 내성 Acinetobacter species 53균주를 대상으로 fluoroquinolone 내성기전을 조사했다. 항균제 감수성 양상을 조사하기 위해 디스크확산법이 시행되었다. Fluoroquinolone 내성과 관련된 유전자 및 돌연변이 검출을 위해 PCR과 염기서열분석이 이루어졌다. 본 연구에서 수집된 53균주의 ciprofloxacin 내성 Acinetobacter 중 47균주가 gyrA 유전자의 83번째 serine 아미노산 잔기와 parC 유전자의 80번째 serine 아미노산 잔기가 leucine 잔기로 치환된 sense mutations 가지고 있는 것으로 나타났다. gyrA와 parC 유전자에 sense mutations을 가지고 있는 47균주 중 44균주가 A. baumannii 였고 3균주는 A. pittii였다. 본 연구에서 조사대상이 되었던 Acb complex 균주들 중 plasmid-mediated quinolone resistance (PMQR) determinants를 가지고 있는 균주는 한나도 없었다. 46 균주의 ciprofloxacin 내성 A. baumannii 는 A, B, 또는 F형의 banding pattern을 보였는데 이는 충청지역에 위치한 일개의 병원에 ciprofloxacin 내성 A. baumannii가 수평확산 되어 있음을 의미한다. Fluoroquinolone 내성 Acb complex 균주의 집락화 및 확산을 막기 위해서 다제내성 균주들을 대상으로 항균제 내성인자들을 지속적으로 조사하고 모니터링할 필요가 있을 것으로 사료된다.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2007년도 공동학술대회 논문집
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• pp.209-214
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• 2007

In Korean geology that crystalline rock is dominant, the properties of subsurface including the anisotropy are distributed complexly and changed abruptly. Because of such geological environments, cross-hole seismic traveltime tomography is widely used to obtain the high resolution image of the subsurface for the engineering purposes in the geotechnical sites. However, because the cross-hole tomography has a wide propagation angle coverage relatively, its data tend to include the seismic velocity anisotropy comparing with the surface seismic methods. It can cause the misinterpretation that the cross-hole seismic data including the anisotropic effects are analyzed and treated with the general processing techniques assuming the isotropy. Therefore, we need to consider the seismic anisotropy in cross-hole seismic traveltime tomography. The seismic anisotropic tomography algorithm, which is developed for evaluation of the velocity anisotropy, includes several inversion schemes in order to make the inversion process stable and robust. First of all, the set of the inversion parameters is limited to one slowness, two ratios of slowness and one direction of the anisotropy symmetric axis. The ranges of the inversion parameters are localized by the pseudo-beta transform to obtain the reasonable inversion results and the inversion constraints are controlled efficiently by ACB(Active Constraint Balancing) method. Especially, the inversion using the Fresnel volume is applied to the anisotropic tomography and it can make the anisotropic tomography more stable than ray tomography as it widens the propagation angle coverage.