• Journal of Power Electronics
• /
• 제13권2호
• /
• pp.313-321
• /
• 2013

This paper describes the operation analysis results of a communication-based DC micro-grid using a hardware simulator developed in the lab. The developed hardware simulator is composed of distributed generation devices such as wind power, photovoltaic power and fuel cells, and energy storage devices such as super-capacitors and batteries. Whole system monitoring and control was implemented using a personal computer. The power management scheme was implemented in a main controller based on a TMS320F28335 chip. The main controller is connected with the local controller in each of the distributed generator and energy storage devices through the communication link based on a CAN or an IEC61850. The operation analysis results using the developed hardware simulator confirm the ability of the DC micro-grid to supply the electric power to end users.

• 펄프종이기술
• /
• 제39권2호
• /
• pp.54-59
• /
• 2007

Cereal, computer software, wine, small appliances, and fast foods are examples of products that have switched from folding carton to microflute corrugated paperboard. Microflute corrugated paperboards have their unique wonderful packaging characteristics that are driving forces for people to use more and more. Good strength property, excellent shock absorbing ability, and beautiful outer appearance of microflute corrugated paperboards go hand and hand with their environmental advantages. It is known that physical properties of microflute corrugated paperboards depend on not only properties of base paper but corrugator operating conditions. This study was carried out to investigate on the corrugator's optimum operating conditions for making micro flute corrugated paperboards. Lab-scaled micro flute corrugator was installed and run with systematic changes of operation conditions to investigate the effects of operation conditions on physical properties of micro flute corrugated paperboards.

• 한국지능시스템학회:학술대회논문집
• /
• 한국퍼지및지능시스템학회 2003년도 ISIS 2003
• /
• pp.216-219
• /
• 2003

Among the techniques to protect private information by adopting biometrics, speaker verification is expected to be widely used due to advantages in convenient usage and inexpensive implementation cost Speaker verification should achieve a high degree of the reliability in the verification nout the flexibility in speech text usage, and the efficiency in verification system complexity. Continuants have excellent speaker-discriminant power and the modest number of phonemes in the category, and multilayer perceptrons (MLPs) have superior recognition ability and fast operation speed. In consequence, the two provide viable ways for speaker verification system to obtain the above properties. This paper implements a system to which continuants and MLPs are applied, and evaluates the system using a Korean speech database. The results of the experiment prove that continuants and MLPs enable the system to acquire the three properties.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제12권6호
• /
• pp.2861-2880
• /
• 2018

Mobile Ad hoc Networks (MANETs) have become a viable platform owing to their potential of providing communication without any pre-existing infrastructure and central administrating authority. Mutual support and co-operation among nodes are prerequisites for performing functions in such networks. The scarcity of resources makes it economical for nodes to conserve their resources and misbehave by avoiding participation in the network. Therefore, a mechanism is required to detect and handle such misbehaving nodes and promote co-operation in the network. Existing techniques for handling misbehaving nodes focus only on their current behaviour without considering the antecedent behaviour of nodes. In real world, a node may dynamically change its behaviour in accordance to its requirements. Hence, an efficient mechanism is required for providing security against such misbehaviour. This paper proposes an Adaptive Security Model which contemplates the present as well as anterior behaviour of nodes for providing security against dynamic node behaviour. The adaptivity of the model is nested in its ability to requite well-behaving nodes and penalize misbehaving ones in conformity with their overall behaviour. Simulation results indicate the efficiency of proposed scheme in securing the network from the menace of dynamic behaviour of nodes.

• Journal of Power Electronics
• /
• 제17권3호
• /
• pp.579-589
• /
• 2017

In this study a new high step-up dc-dc converter is presented. The operation of the proposed converter is based on the capacitor switching and coupled inductor with a single active power switch in its structure. A passive voltage clamp circuit with two capacitors and two diodes is used in the proposed converter for elevating the converter's voltage gain with the recovered energy of the leakage inductor, and for lowering the voltage stress on the power switch. A switch with a low $R_{DS}$ (on) can be adopted to reduce conduction losses. In the generalized mode of the proposed converter, to reach a desired voltage gain, capacitor stages with parallel charge and series discharge techniques are extended from both sides of secondary side of the coupled inductor. The proposed converter has the ability to alleviate the reverse recovery problem of diodes with circuit parameters. The operating principle and steady-states analyses are discussed in detail. A 40W prototype of the proposed converter is implemented in the laboratory to verify its operation.

• 정보교육학회논문지
• /
• 제7권2호
• /
• pp.207-217
• /
• 2003

웹을 활용한 다양한 수업전략으로 정보의 수집을 통하여 지식을 구성하고 학습의 효율성을 높이는 개별학습과 타인과의 의사교환을 통해 책임감과 문제 해결력을 기를 수 있는 협동학습이 활발히 개발되고 있다. 그러나 현재 개발되어 있는 개별학습자료는 대부분 자료의 제시형태로 학습이 진행되어 학습자의 흥미를 유발하고, 문제에 대한 호기심을 자극하기에 적합하지 않다. 또한 협동학습자료는 현장의 교육과정과 연계성이 부족하여 수업 현장에서 적용이 어려운 실정이다. 따라서 본 연구에서는 다양한 사고력을 신장시킬 수 있도록 흥미있는 조작활동 위주의 자기주도적 학습을 적용하였다. 또한 의사 결정력과 ICT 활용능력을 향상시킬 수 있는 온라인 프로젝트학습을 함께 연계하여 운영이 가능하도록 사회과 교수-학습 시스템을 개발하였다. 본 시스템은 다양한 수업환경에 맞춰 융통성있는 운영이 가능하고, 형성평가를 통하여 수준별 학습이 이루어지며 평가결과는 피드백하여 활용할 수 있도록 개발하였다.

• 한국산업융합학회 논문집
• /
• 제10권2호
• /
• pp.115-122
• /
• 2007

The MPC(Moisture Protected Computer) system is completely unique. It was recently invented in Korea and it is a technological break-through in the field of computer systems. It will be instrumental in the development of a complete moisture air-tight capability and will work well in field environments. The MPC includes the following: 1) An enclosed design. 2) Moisture proof computer enclosure joints. 3) System dust protection & an impact buffing system. 4) A normal temperature maintenance system when the temperature inside the computer is low. 5) The ability to generate heat and a radiate system inside the computer 6) An automatic power input sensing controller device. 7) A safety device in case of mis-operation. 8) A proper admission procedure for various tests. Because of the above, and as a result of temperature property experiments, there aren't any operational problems. The result of this treatise could provide very important data for verification of cases involving: using strong materials to protect against explosions, searching for ways to make the size and weight small, and for making repairs easier. As a result, it could achieve price and function competitiveness in advanced countries such as the USA and in Europe.

• International journal of advanced smart convergence
• /
• 제9권4호
• /
• pp.179-183
• /
• 2020

The online education platform market is developing rapidly after the coronavirus infection-19 pandemic. As school classes at various levels are converted to non-face-to-face classes, interest in non-face-to-face online education is increasing more than ever. However, the majority of online platforms currently used are limited to the fragmentary functions of simply delivering images, voice and messages, and there are limitations to online hands-on training. Indeed, digital transformation is a traditional business method for increasing coding education and a corporate approach to service operation innovation strategy computing thinking power and platform model. There are many ways to evaluate a computer programmer's ability. Generally, piecemeal evaluation methods are used to evaluate results in time through coding tests. In this study, the purpose of this study is to propose a comprehensive evaluation of not only the results of writing, but also the execution process of the results, etc., and to evaluate the programmer's propensity habits based on the programmer's coding experience to evaluate the programmer's ability and productivity.

• 한국컴퓨터정보학회논문지
• /
• 제25권8호
• /
• pp.39-45
• /
• 2020

최근에 사이버 보안에 대한 관심이 많이 증가함에도 불구하고 신기술들의 등장으로 사이버 보안을 효율적으로 수행할 전문적인 인력이 부족한 실정이다. 사이버 보안 전문인력 양성을 위해 사이버 레이지와 같은 다양한 방법이 활용하고 있음에도 가상훈련 시스템의 한계성, 시나리오 기반의 실습 콘텐츠 개발과 운용상, 단위 콘텐츠 중심 개발, 학습자 수준 고려 부족의 문제점이 있다. 본 논문에서는 사이버보안 훈련체계 사용자의 침해대응 능력을 향상하는 목적으로 퍼지 규칙 기반의 사용자 맞춤형 훈련 시나리오 자동 생성 시스템을 개발한다. 제안하는 시스템은 퍼지 규칙을 따라 지능형 지속 위협 기반으로 시나리오를 생성하고 제공한다. 그리하여 제안 시스템은 생성된 시나리오를 통해 훈련생의 침해 대응 능력을 향상시킬 수 있다.

• International Journal of Advanced Culture Technology
• /
• 제10권3호
• /
• pp.371-376
• /
• 2022

The purpose of this study is to develop a walking assistance system with mobility support and life support functions so that the elderly with reduced physical ability and patients who are uncomfortable when moving can move comfortably indoors and outdoors, and help social life. An obstacle recognition sensor module that can be applied indoors and outdoors is installed on a lightweight walking aid. The purpose of this study is to develop a walking assistance system with mobility support and life support functions so that the elderly with reduced physical ability and patients who are uncomfortable when moving can move comfortably indoors and outdoors, and help social life. An obstacle recognition sensor module that can be applied indoors and outdoors is installed on a lightweight walking aid. It is a system structure of an integrated actuator and brake system that can avoid obstacles in consideration of the safety of the elderly and is easy to install on the device. In this paper, the design of a lightweight walking aid was designed to increase the convenience of the socially disadvantaged and the elderly with reduced exercise ability. In addition, in order to overcome the disadvantage of being inconvenient to use indoors due to the noise and vibration of the motor during operation, an In-Wheel type motor is applied to develop and apply a low noise, low vibration and high efficiency drive system.