• BMB Reports
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• 제37권1호
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• pp.83-92
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• 2004

As a result of the enormous amount of information that has been collected with E. coli over the past half century (e.g. genome sequence, mutant phenotypes, metabolic and regulatory networks, etc.), we now have detailed knowledge about gene regulation, protein activity, several hundred enzyme reactions, metabolic pathways, macromolecular machines, and regulatory interactions for this model organism. However, understanding how all these processes interact to form a living cell will require further characterization, quantification, data integration, and mathematical modeling, systems biology. No organism can rival E. coli with respect to the amount of available basic information and experimental tractability for the technologies needed for this undertaking. A focused, systematic effort to understand the E. coli cell will accelerate the development of new post-genomic technologies, including both experimental and computational tools. It will also lead to new technologies that will be applicable to other organisms, from microbes to plants, animals, and humans. E. coli is not only the best studied free-living model organism, but is also an extensively used microbe for industrial applications, especially for the production of small molecules of interest. It is an excellent representative of Gram-negative commensal bacteria. E. coli may represent a perfect model organism for systems biology that is aimed at elucidating both its free-living and commensal life-styles, which should open the door to whole-cell modeling and simulation.

• 조명전기설비학회논문지
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• 제27권7호
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• pp.67-75
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• 2013

In this paper, parallel input/serial output dual converter is designed appropriately for fuel cell hybrid power system. In case of proposed converter, zero voltage switching condition is designed without additional resonance device using leakage inductance of transformer and output capacitance of switch, and zero voltage switching method is used. Also, the system method is for increasing power by connecting half-bridge in parallel and increasing output voltage by connecting secondary output of transformer in serial. Through this method we can increase power and decrease volume of system. So in this paper, dual converter is designed. 1.5kW fuel cell hybrid power system was implemented, and system operation and stability was verified through experiment.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.972-975
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• 2003

We have performed computer simulation to obtain electro-optic characteristics of reflective hybrid aligned nematic liquid crystal displays driven by fringe field. The results show that the optimal retardation value of the cell is $0.289{\mu}m$, which allows for the cell to have a practical cell gap of larger than $3{\mu}m$ when manufacturing. A reflectance of the dark state is only 0.114% for an incident light 550nm. At this condition, the light efficiency of white state reaches 92.7%. Further, we have studied a new reflective display with polarizer, optical compensation with half plate, LC plus reflector. The display with optimized cell parameters shows low wavelength dispersion and the contrast ratio greater than 5 over exists about $120^{\circ}$ in vertical direction and $160^{\circ}$ in horizontal direction.

• 한국전기전자재료학회논문지
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• 제13권8호
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• pp.688-693
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• 2000

In this paper an optical voltage sensor and an optical current sensor which can be used for the measurement of impulse voltage and current are implemented. BSO single crystal is utilized as a voltage sensor(Pockels effect cell). An rare earth doped YIG is used as a current sensor(Faraday effect cell). A new signal processing technique is adopted not only to avoid the influences o external optical fiber pertubations of transmitting optical fiber but also to improves the frequency response characteristics of the fiber-optic voltage and current sensors. Experimental results show that optical voltage sensor has maximum 2.5% error within the voltage range from 0V to 500V. and optical current sensor has maximum 2.5% error within the current range and that of optical current sensor is about 1.5% within temperature range from -2$0^{\circ}C$ to 6$0^{\circ}C$. The proposed optical sensors have good frequency response characteristics within the frequency range from DC to 10MHz.

• Current Photovoltaic Research
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• 제1권1호
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• pp.11-16
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• 2013

The current solar cell industry is experiencing a temporary plateau due to a sluggish economy and oversupply. It is expected that the solar industry can see similar growth to that of the recent past by overcoming the current situation, as there is growing demand globally for solar energy. The current situation led to restructuring of the world's solar industry, and domestic firms will need to have competitiveness through strategic approaches and proprietary technology to survive in the global solar market. Crystalline and amorphous silicon based solar cells have led the solar industry and occupied half or more of the market thus far. They will do so in the future PV market as well by playing a pivotal role in the solar industry. In this paper, the current status and prospects of silicon based solar cells, from materials to comprehensive and high efficiency technology that can emerge in the future, are discussed.

• 대한후두음성언어의학회지
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• 제32권1호
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• pp.48-50
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• 2021

More than half of patients presenting with hoarseness show benign vocal cord changes. However, in rare cases with benign mucosal lesions, it can be diagnosed as a malignant disease after histopathological examination. A 53-year-old man with a 30-pack-year smoking history was admitted for the evaluation of hoarseness, and using a laryngoscope, an enclosed, sac-like cystic lesion was detected on the midpoint of the right true vocal cord. The cystic lesion was deemed to be an intracordal cyst and treated with laryngeal microsurgery. However, pathological findings showed squamous cell carcinoma of the larynx arising in the intracordal cyst, which is exceptionally rare. Therefore, even if a benign lesion is initially suspected, a biopsy must be performed on a patient with smoking history to confirm the diagnosis. In conclusion, we report a case of squamous cell carcinoma of the larynx arising in the intracordal cyst.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제49권5호
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• pp.292-296
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• 2023

Generally, if the size of a lip cancer defect exceeds 30% of the lower lip, a local flap or free flap is recommended. However, defects up to 50% of the lower lip in size have been reconstructed successfully by primary closure without a local flap or free flap. In one case, an 80-year-old male farmer who had smoked for more than 50 years presented with squamous cell carcinoma of the lower lip and underwent mass resection and supraomohyoid neck dissection. The defect accounted for almost 2/3 of the lower lip and was repaired by primary closure with V-shaped resection. Biopsy results confirmed pT2N0cM0 stage II disease with clear margins. In another case, a 68-year-old male also presented with squamous cell carcinoma of the lower lip and underwent mass resection. The defect accounted for about half the size of the lower lip but was repaired by primary closure with V-shaped resection. Both patients experienced no discomfort while eating or speaking and were satisfied with the cosmetic and functional outcomes with no evidence of recurrence. Thus, direct closure can be considered even in large lower lip cancers.

• Fisheries and Aquatic Sciences
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• 제27권1호
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• pp.17-22
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• 2024

Diabetes Mellitus (DM) is a major health issue increasing worldwide. Currently, nearby half a billion people have diabetes. Two major types of DM that type 1 and type 2-DM have different etiologies but feature a crucial common pathological transition into dysfunction of pancreatic β-cells and consequently leading hyperglycemia and finally go into DM. Therefore, maintaining of β-cells such as preventing β-cells degeneration, and promoting β-cells regeneration and proliferation will be essential approaches in prevention and/or treatment of DM. There are many reports that various types of seaweed control metabolic diseases such as obesity, high blood pressure, and blood sugar control. However, no new drug candidates have been developed yet. Additionally, although seaweed has excellent blood sugar control effects, there is no evidence that it directly proliferates or regenerates beta cells. Therefore, we studied on the promotion of β-cell regeneration by a seaweed, Polysiponia morrowii extract (PME) which preserves β-cells and maintains its function. As a result, it was confirmed that PME directly promotes the proliferation of pancreatic islet β-cells with insulin secretion function in in vivo. Therefore, PME shows potential as a candidate for β-cell regeneration that may play a fundamental role in the treatment of diabetes.

• 대한전자공학회논문지SD
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• 제45권8호
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• pp.1-10
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• 2008

본 논문에서는 새로운 스위칭 방식인 LFS (Local Field Switching)을 이용하여 설계한 128비트 MRAM (Magnetoresistive Random Access Memo교)에 대해 기술하였다. LFS 방식은 MTJ (Magnetic Tunnel Junction)를 직접 통과해 흐르는 전류에 의해 형성되는 국소 자기장을 이용하여 MTJ의 극성을 변환시킨다. 이 방식은 MTJ와 전류의 거리가 가깝기 때문에 작은 전류로도 충분히 큰 자기장을 형성하므로 writing current가 적어도 된다. 또한 Digit Line이 없어도 되므로 half select disturbance가 발생하지 않아 기존 MTJ를 이용한 방식에 비해 셀 선택도가 우수하다. 설계한 MRAM은 IT(트랜지스터)-1MTJ의 메모리 셀 구조를 가지며 양방향 write driver와 mid-point reference cell block, current mode sense amplifier를 사용한다. 그리고 MTJ 공정 없이 회로 동작을 확인하기 위해 LFS-MTJ cell을 CMOS emulation cell로 대체하였다. 설계한 회로를 6 metal을 사용하는 $0.18{\mu}m$ CMOS 공정으로 구현하였고 제작된 chip을 custom board 상에서 테스트하여 동작을 확인하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1993년도 봄 학술발표회 논문집
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• pp.73-78
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• 1993

This study was performed for the purposes of estimating steel corrosion of concrete structures under the environment of seawater. The corrosion of steel was accelerated in artificial seawater with seven kinds of specimen which was embedded in mortar. By measuring choride content in mortar, half cell potential and corrosion area ratio, the degree of steel corrosion can be assumed.