• Smart Structures and Systems
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• 제12권1호
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• pp.1-22
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• 2013

Magnetic nanoparticle based bioseparation in microfluidics is a multiphysics phenomenon that involves interplay of various parameters. The ability to understand the dynamics of these parameters is a prerequisite for designing and developing more efficient magnetic cell/bio-particle separation systems. Therefore, in this work proof-of-concept experiments are combined with advanced numerical simulation to design and optimize the capturing process of magnetic nanoparticles responsible for efficient microfluidic bioseparation. A low cost generic microfluidic platform was developed using a novel micromolding method that can be done without a clean room techniques and at much lower cost and time. Parametric analysis using both experiments and theoretical predictions were performed. It was found that flow rate and magnetic field strength greatly influence the transport of magnetic nanoparticles in the microchannel and control the capturing efficiency. The results from mathematical model agree very well with experiments. The model further demonstrated that a 12% increase in capturing efficiency can be achieved by introducing of iron-grooved bar in the microfluidic setup that resulted in increase in magnetic field gradient. The numerical simulations were helpful in testing and optimizing key design parameters. Overall, this work demonstrated that a simple low cost experimental proof-of-concept setup can be synchronized with advanced numerical simulation not only to enhance the functional performance of magneto-fluidic capturing systems but also to efficiently design and develop microfluidic bioseparation systems for biomedical applications.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제18권3호
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• pp.720-737
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• 2024

Private set intersection cardinality (PSI-CA) is a typical problem in the field of secure multi-party computation, which enables two parties calculate the cardinality of intersection securely without revealing any information about their sets. And it is suitable for private data protection scenarios where only the cardinality of the set intersection needs to be calculated. However, most of the currently available PSI-CA protocols only meet the security under the semi-honest model and can't resist the malicious behaviors of participants. To solve the problems above, by the application of the variant of Elgamal cryptography and Bloom filter, we propose an efficient PSI-CA protocol with high security. We also present two new operations on Bloom filter called IBF and BIBF, which could further enhance the safety of private data. Using zero-knowledge proof to ensure the safety under malicious adversary model. Moreover, in order to minimize the error in the results caused by the false positive problem, we use Garbled Bloom Filter and key-value pair packing creatively and present an improved PSI-CA protocol. Through experimental comparison with several existing representative protocols, our protocol runs with linear time complexity and more excellent characters, which is more suitable for practical application scenarios.

• Journal of Advanced Marine Engineering and Technology
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• 제36권1호
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• pp.64-71
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• 2012

An efficient cooling system is an essential part of the electronic packaging such as a high-luminance LED lighting. A special technology, Pulsating Heat Pipe (PHP), can be applied to improve cooling of a sealed, explosion-proof LED light fixture. In this paper, the characteristics of the pulsating heat pipes in the imposed thermal boundary conditions of LED lightings were experimentally investigated and a PHP device that works free of alignment angle was investigated for cooling of explosion-proof LED lights. Five working fluids of ethanol, FC-72, R-123, water, and acetone were chosen for comparison. The experimental pulsating heat pipe was made of copper tubes of internal diameter of 2.1 mm, 26 turns. A variable heat source of electric heater and an array of cooling fins were attached to the pulsating heat pipe. For the alignment of the heating part at bottom, an optimum charging ratio (liquid fluid volume to total volume) was about 50% for most of the fluids and water showed the highest heat transfer performance. For the alignment of the heating part on top, however, only R-123 worked in an un-looped construction. This unique advantage of R-123 is attributed to its high vapor pressure gradient. Applying these findings, a cooling device for an explosion-proof type of LED light rated 30 W was constructed and tested successfully.

• 한국가스학회지
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• 제19권6호
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• pp.105-109
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• 2015

본 연구는 해상 유류오염사고가 발생한 경우 효율적인 방재 작업을 수행하기 위하여 개발된 오일 회수장치로서, 오일 회수장치를 통하여 해상에 유출된 기름을 높은 회수율로 신속하게 처리하는 것을 목표로 한다. 오일 회수장치는 기존의 흡착포 및 유류처리제를 이용한 정화 방식에서 발생하는 2차 오염을 방지할 수 있으며 오일 회수율 또한 우수한 특징을 가진다. 또한 유증기에 의한 폭발 방지 기구를 채택하여 오일 회수 작업시 발생할 수 있는 위험 요소를 제거 하였다.

• 자원ㆍ환경경제연구
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• 제11권1호
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• pp.31-55
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• 2002

When landowners have private information about land value, compensation based on conservation value at the time of regulatory takings of land is impractical even though it generates an efficient outcome. No compensation rule to a landowner not only yields an inefficient outcome but also provides an ex ante pervasive incentive for the landowner to invest in lowering conservation value. An alternative rule of compensation based on the market value of the land provides ex ante incentives for landowner either to reduce conservation value or to increase it. Under the market value compensation rule, placing the burden of proof on landowner gives higher probability of conservation than placing it on regulator. Whether it is better to allure landowners to conserve by paying compensation with market value and placing the burden of proof on landowner through changes in the regulatory regime however depends on the magnitude of inefficiency, equity consideration and dynamic nature of property rights on environmental goods.

• International Journal of Railway
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• 제6권3호
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• pp.125-130
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• 2013

Most of the test methods used for determining the acoustic performance of the noise barriers in Korean standards address the sound-proof panels but refer to noise barriers as a whole system or their in-situ performances less. Many new types of trains with different operating speeds have been developed and produced, and civil appeals against railway noise are becoming quite extensive. Considering these latest changes of circumstances, it is necessary to investigate the current standards and specifications pertaining to railway noise barriers. In this paper, criteria for the measurements and evaluations of noise barriers and sound-proof panels are examined and experimental studies are introduced. In order to suggest more efficient methods for reasonable evaluations of the noise barriers, frequency spectrums of the noise source, the power of the actual railway vehicles, are investigated and introduced.

• 정보과학회 논문지
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• 제43권10호
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• pp.1165-1172
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• 2016

클라우드 스토리지 환경에서 중복제거 기술은 스토리지의 효율적인 활용을 가능하게 한다. 또한 클라우드 스토리지 서비스 제공자들은 네트워크 대역폭을 절약하기 위해 클라이언트 측 중복제거 기술을 도입하고 있다. 클라우드 스토리지 서비스를 이용하는 사용자들은 민감한 데이터의 기밀성을 보장하기 위해 데이터를 암호화하여 업로드하길 원한다. 그러나 일반적인 암호화 방식은 사용자마다 서로 다른 비밀키를 사용하기 때문에 중복제거와 조화를 이룰 수 없다. 또한 클라이언트 측 중복제거는 태그 값이 전체 데이터를 대신하기 때문에 안전성에 취약할 수 있다. 최근 클라이언트 측 중복제거의 취약점을 보완하기 위해 소유권 증명 기법들이 제안되었지만 여전히 암호데이터 상에서 클라이언트 측 중복제거 기술은 효율성과 안전성에 문제점을 가지고 있다. 본 논문에서는 전수조사 공격에 저항성을 갖고 암호데이터 상에서 소유권 증명을 수행하는 안전하고 실용적인 클라이언트 측 중복제거 기술을 제안한다.

• Journal of Information Processing Systems
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• 제8권2호
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• pp.375-388
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• 2012

PVSS stands for publicly verifiable secret sharing. In PVSS, a dealer shares a secret among multiple share holders. He encrypts the shares using the shareholders' encryption algorithms and publicly proves that the encrypted shares are valid. Most of the existing PVSS schemes do not employ an ElGamal encryption to encrypt the shares. Instead, they usually employ other encryption algorithms like a RSA encryption and Paillier encryption. Those encryption algorithms do not support the shareholders' encryption algorithms to employ the same decryption modulus. As a result, PVSS based on those encryption algorithms must employ additional range proofs to guarantee the validity of the shares obtained by the shareholders. Although the shareholders can employ ElGamal encryptions with the same decryption modulus in PVSS such that the range proof can be avoided, there are only two PVSS schemes based on ElGamal encryption. Moreover, the two schemes have their drawbacks. One of them employs a costly repeating-proof mechanism, which needs to repeat the dealer's proof at least scores of times to achieve satisfactory soundness. The other requires that the dealer must know the discrete logarithm of the secret to share and thus weakens the generality and it cannot be employed in many applications. A new PVSS scheme based on an ElGamal encryption is proposed in this paper. It employs the same decryption modulus for all the shareholders' ElGamal encryption algorithms, so it does not need any range proof. Moreover, it is a general PVSS technique without any special limitation. Finally, an encryption-improving technique is proposed to achieve very high efficiency in the new PVSS scheme. It only needs a number of exponentiations in large cyclic groups that are linear in the number of the shareholders, while all the existing PVSS schemes need at least a number of exponentiations in large cyclic groups that are linear in the square of the number of the shareholders.

• 한국중재학회지:중재연구
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• 제26권4호
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• pp.129-149
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• 2016

Medical dispute means the dispute between the hospital and the patient due to a medical accident. In general, medical accidents must be in accordance with the terms that are used in the medical dispute adjustment method stated in Article 2 (definition). In relation to this, there is a need to discuss an efficient operation scheme for Alternative Dispute Resolution (ADR) in medical disputes. In addition, it is necessary to look at issues of civil liability and criminal liability. In particular, in the consumer dispute arbitration committee, there is a case to make a "decision not to adjust" in aggressive intervention in the process of conflict resolution. The medical staff, on the basis of its "decision," can use this as a proven material for civil and criminal cases. This is rather upon the determination of the consumer council as a typical side effect to defend the user's perspective. This is the "decision" as was expressed from an order, "not adjusted." It is also determined to be easy and clearly timely. In the medical litigation, it is requesting the burden of proof of a patient's cause-and-effect relationship with the doctors committing negligence and medical malpractice. This seems to require the promotion of legislation in the direction to reduce future cases. It is determined that the burden of proof of medical accidents must be improved. The institution receiving the medical accident should prevent a closure report. Further, it is necessary to limit the transition to a franchise point. In this paper, we understand the problems of the current medical dispute resolution system, trying to establish a medical dispute resolution system desirable through an efficient alternative. In addition, it wants help in the protection and realization in medical consumers' and patients' rights. The relevant authorities will take advantage of these measures. After all, this could contribute to the system for a smooth resolution of a medical dispute.

• 한국정보통신학회논문지
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• 제9권4호
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• pp.816-823
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• 2005

비혼(non-Horn) 논리 프로그램은 혼(Horn) 논리 프로그램을 1계 술어 논리(1st order predicate logic) 수준으로 확장하였기 때문에 표현력은 크지만 효율적으로 구현된 사례가 없어서 실용적인 언어로 사용되지는 못하였다. 지금까지 연구된 효율적인 방법은 비혼 논리 프로그램을 증명절차 InH-Prolog의 의미를 이용하여 동등한 혼 논리 프로그램으로 변환한 후 변환된 혼 논리 프로그램을 WAM(Warren Abstract Machine) 명령어로 컴파일하여 수행시키는 방법이다. 본 논문에서는 이 방법을 향상시키기 위하여 비혼 논리 프로그램을 효율적으로 수행하는 EWAM(Extended WAM)과 비혼 논리 프로그램을 EWAM 명령어로 컴파일하는 방법을 제안한다. 또한 본 논문에서는 제안한 EWAM의 에뮬레이터 및 컴파일러를 구현하여 그 성능을 측정하였다. 본 논문에서 구현한 EWAM 에뮬레이터 및 컴파일러의 성능을 측정한 결과 기존 방법보다 매우 효율적임을 확인하였다.