• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2009.11a
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• pp.91-92
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• 2009

• Journal of the Korean Society for Aviation and Aeronautics
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• v.6 no.1
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• pp.99-109
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• 1998

• Journal of the Korea Institute of Information Security & Cryptology
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• v.20 no.6
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• pp.209-220
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• 2010

Evaluating performance in public sector aims to enhance the efficiency of organizations. Evaluating the efficiency which is the ratio between input and output, organizations set directions of improvement. This research applied Data Envelopment Analysis(DEA) useful to evaluating the efficiency of organizations in public sector. Decision Making Units(DMU) of this research are 21 Information Security Organizations of departments/agencies. As the results, the mean of efficiency score of 21 DMUs is a little more than 50%. Means of departments(8 DMUs) and agencies/committees(11 DMUs) are similar to the total efficiency score. For these results, the decision makers of the information security organizations in public sector have to strive to improve the inefficiency.

• 산림경영
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• s.133
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• pp.4-7
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• 1998

과거의 조림을 중심으로 하던 녹화임정을 산림의 이용을 증진하도록 하는 경영임정으로 바꾸기 위한 패러다임 전환은 1.적극적인 산업정신 형성 2.시대통찰력 가진 전문가 양성 3.산림경영의 비효율성 제거방안 4. 산림경영모델(범위경영) 확립 5.정부의 실질적인 역할조정 등 5가지 주요문제를 검토하여 우리실정에 맞도록 새롭게 정립하여야 한다.

• The KIPS Transactions:PartC
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• v.17C no.1
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• pp.27-36
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• 2010

In Web registration pages and online polling applications, CAPTCHA(Completely Automated Public Turing Test To Tell Computers and Human Apart) is used for distinguishing human users from automated programs. Text-based CAPTCHAs have been widely used in many popular Web sites in which distorted text is used. However, because the advanced optical character recognition techniques can recognize the distorted texts, the reliability becomes low. Image-based CAPTCHAs have been proposed to improve the reliability of the text-based CAPTCHAs. However, these systems also are known as having some drawbacks. First, some image-based CAPTCHA systems with small number of image files in their image dictionary is not so reliable since attacker can recognize images by repeated executions of machine learning programs. Second, users may feel uncomfortable since they have to try CAPTCHA tests repeatedly when they fail to input a correct keyword. Third, some image-base CAPTCHAs require high communication cost since they should send several image files for one CAPTCHA. To solve these problems of image-based CAPTCHA, this paper proposes a new CAPTCHA based on both image and text. In this system, an image and keywords are integrated into one CAPTCHA image to give user a hint for the answer keyword. The proposed CAPTCHA can help users to input easily the answer keyword with the hint in the fused image. Also, the proposed system can reduce the communication costs since it uses only a fused image file for one CAPTCHA. To improve the reliability of the image-text fusion CAPTCHA, we also propose a dynamic building method of large image dictionary from gathering huge amount of images from theinternet with filtering phase for preserving the correctness of CAPTCHA images. In this paper, we proved that the proposed image-text fusion CAPTCHA provides users more convenience and high reliability than the image-based CAPTCHA through experiments.

• Resources Recycling
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• v.33 no.2
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• pp.16-23
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• 2024

The electrolysis for extracting magnesium from seawater or brine primarily involves recovery of magnesium via precipitation as the form of magnesium hydroxide. The technology is classified into cation-exchange membranes (CEM), anion-exchange (AEM) membranes, electrodialysis, and membraneless methods. Recent research has focused on enhancing the efficiency and selectivity of magnesium recovery from seawater or brine containing magnesium, with expectations of effective magnesium recovery even with normal seawater. In a future, the optimization of the selective and efficient recovery of magnesium and various valuable substances through long-term operation of scaled-up systems is crucial with enhancing economic and environmental viability. It is essential to realistically estimate operational costs considering the membrane's lifespan and replacement cycle. Also, detailed and practical process models should be developed based on monitoring data on various factors.

• Journal of Animal Science and Technology
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• v.49 no.2
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• pp.279-286
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• 2007

A submerged biofilm sequencing batch reactor (SBSBR) process, which liquor was internally circulated through sandfilter, was designed, and performances in swine wastewater treatment was evaluated under a condition of no external carbon source addition. Denitrification of NOx-N with loading rate in vertical and slope type of sandfilter was 19% and 3.8%, respectively, showing approximately 5 times difference, and so vertical type sandfilter was chosen for the combination with SBSBR. When the process was operated under 15 days HRT, 105L/hr.m3 of internal circulation rate and 54g/m3.d of NH4-N loading rate, treatment efficiencies of STOC, NH4-N and TN (as NH4-N plus NOx-N) was 75%, 97% and 85%, respectively. By conducting internal circulation through sandfilter, removal performances of TN were enhanced by 14%, and the elevation of nitrogen removal was mainly attributed to occurrence of denitrification in sandfilter. Also, approximately 57% of phosphorus was removed with the conduction of internal circulation through sandfilter, meanwhile phosphorus concentration in final effluent rather increased when the internal circulation was not performed. Therefore, It was quite sure that the continuous internal circulation of liquor through sandfilter could contribute to enhancement of biological nutrient removal. Under 60g/m3.d of NH4-N loading rate, the NH4-N level in final effluent was relatively low and constant(below 20mg/L) and over 80% of nitrogen removal was maintained in spite of loading rate increase up to 100g/m3.d. However, the treatment efficiency of nitrogen was deteriorated with further increase of loading rate. Based on this result, an optimum loading rate of nitrogen for the process would be 100g/m3.d.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1999.04a
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• pp.94-96
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• 1999

충북 단양에 위치한 조일 광산에서 채취한 구리와 아연으로 오염된 광미(광산 폐기물로서 금속 추출 후 남은 찌꺼기)를 효율적으로 처리하기 위한 생물학적 용출기법(bioleaching) 에서 기본 배지 조성(9K medium)을 변화시켜 미생물의 표면 특성을 측정하고 미생물 표면 특성이 용출 효율에 미치는 영향을 관찰하였다. 인을 첨가하지 않았을 때 소수성 값은 62.5％, 질소원 농도가 45mM일 때의 소수성 값은 66.7%로 미생물 표면 특성이 가장 소수성인 특성을 가지고 있었으며, 구리와 아연의 용출 효율도 가장 높게 나타나는 상관 관계를 나타냈다. 또한 광미에 부착된 미생물의 양을 측정해 본 결과, 미생물 표면 특성이 소수성일수록 광미에 부착된 미생물의 양도 많다는 것을 알 수 있었다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.10A
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• pp.780-787
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• 2003

Adaptive modulation is the method to increase the throughput of the mobile system using the power margin of the system design. In this paper, we propose the method to change adaptive modulation parameters for the stable system operation by monitoring the mobility of the mobile station. The proposed method measures the instanteneous mobility of the mobile station monitoring the closed power control data. The MPSK modulation method is used for the basic modulation method because of the hardware implementation. Using the proposed method we can get the more powerful throughput. By the system simulation to verify the evaluation of the proposed algorithm, we can notice the algorithm is more efficient than the typical method

• 한국정보교육학회:학술대회논문집
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• 2009.08a
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• pp.61-66
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• 2009

프로그래밍 교육이 학습자의 논리적 사고력 증진, 문제해결 능력, 성취감과 자신감 획득 등 학습자의 고등 인지 능력을 발달시킨다는 사실이 많은 연구에서 나타나고 있으며, 다양한 교육용프로그래밍 언어가 개발되어 현장에 적용되고 있다. 또한 프로그래밍 교육의 필요성이 확산됨에 따라 프로그래밍 교육 방안도 다양하게 시도되고 있다. 전통적인 교육에서와 마찬가지로 프로그래밍 학습에서도 효율적인 학습을 위해서는 학습자들의 학습스타일과 다중지능을 고려한 교육이 필요한 실정이다. 즉, 효과적인 프로그래밍 교육을 위해서는 다양한 학습자들의 특성을 파악하고 학습자에게 적합한 교육 방안을 적용하는 것이 필요하다. 따라서 본 연구에서는 효율적인 프로그래밍 교육을 위해 학습자의 학습스타일과 다중지능 간의 관계를 분석하고, 그 결과를 바탕으로 프로그래밍 교육에 있어 학습스타일과 다중지능을 고려한 교육 전략을 제시하였다. 본 연구의 결과는 학습자에게 특성을 고려한 적합한 교육을 실시함으로써 학습자의 흥미를 유발하고, 프로그래밍 교육의 학습효과를 증진하는데 기여하게 될 것이다.