Earticle

4차 산업혁명의 변화 속에서 새로운 성장 동력을 확보하기 위해 융합기술의 중요성이 강조되면서 다양한 형태로 의 산업 융합이 이루어지고 있다. 산업 융합은 다수 동인에 의해 여러 형태로 발현되기 때문에 이러한 융합의 특성을 파악하고 흐름을 이해한다면 효과적인 융합 정책을 수립하고 추진할 수 있을 것이다. 이에 본 연구는 특허정보를 활용 하여 이종 분야 간 지식의 흐름을 분석하여 기술의 융합 형태를 유형화하고 유형별 특성을 파악하는 것을 목적으로 한다. 이를 위해 첫째, 특허문서의 토픽모델링을 통해 핵심 융합 기술분야를 도출한다. 둘째, 해당 기술분야를 구성하는 이종기술별 특허 건수와 이들 간 특허 인용 분석을 통해 융합과정에서의 지식의 규모와 흐름을 파악한다. 마지막으로, 지식의 규모와 흐름에 따라 융합의 유형을 상생융합, 부분융합, 흡수융합으로 구분하고, 해당 기술분야가 어떠한 유형에 속하는지 판단하고자 한다. 제안된 접근법은 이종 기술간 융합이 활발한 의료기기 산업을 대상으로 사례연구를 수행하 여 활용 가능성을 검토하였다. 연구 결과는 향후 기업에서 융합 기반의 신사업 기회 창출이나 정부 등 여러 기관에서 융합을 토대로 한 정책 마련 시 기초자료로서 유용하게 활용될 것으로 기대한다.

Industrial convergence is manifested in various forms by various drivers, and understanding and categorizing the direction of convergence according to the factors in which the convergence occurs is an essential requirement for the establishment of a company's customized convergence strategy and the government's corporate support policy. In this study, the type of convergence is analyzed from the perspective of knowledge flow between heterogeneous technologies, and for this purpose, the result of topic modeling of the text information of the patent and the citation information of the corresponding patent allocated for each topic are used. The methodology presented through case studies in the medical device field is verified. Through the proposed methodology, companies can predict the flow of convergence and use it as decision-making data to create new business opportunities. It is expected that the government and research institutions will be usefully used as basic data for policy preparation.

Tunnel diode is a very important device in industry but it is very difficult to simulate it using any circuit-simulation program. This paper proposes an Analog Behavioral Model (ABM) in Pspice of a tunnel diode. The Pspice parameters are extracted and implemented by deriving the device parameters from the device structure. Most of the device parameters are calculated from estimated values. A tunnel diode based oscillator is also proposed and simulated using circuit analysis software. The model is validated by means of comparison with experimental measurements and with the results obtained from other reference model. Excellent agreement is demonstrated between measured and simulation responses. The proposed implementation can be used in a PSpice program, designed as a subcircuit which can be called when required by the main program.

A numerical model of a three junction device is presented. It allows the simulation of the external characteristics of the PNPN family devices and in this work the simulation of gate turn-off thyristor(GTO) is particularly considered. The proposed PNPN device simulation model solves all the drawbacks presented by the previous work, simulates the GTO well, and fulfills.

In this paper, we propose a Designed and Developed home router management system. Through the fourth industrial revolution and development of IoT technology, now people can experience a wide range of IoT related services at their workplace or daily lives. At the industrial site, IoT devices are used to improve productivity such as factory automation, and at home, IoT technology is used to control home appliances from a remote distance. Usually IoT device is integrated and controlled by the router. Home router connects different IoT devices together at home, however when security issues arise, it can invade personal privacy. Even though these threats exist, the perception for home router security is still insufficient. In this paper, we have designed and developed home router management system using DEVS methodology to promote the safe use of home router. Through the DEVS methodology, we have designed the system and developed the mobile application. This management system enables users to set up security options for home router easily.

본 논문은 기존 파이로 부품인 폭발볼트의 기능을 그대로 유지하면서 분리시 발생되는 파편 및 충격파의 악 작용과 파편을 완벽히 제거할 수 있게 형상기억합금(Shape Memory Alloy)을 이용한 분리장치(Fangibolt) 모델의 설계 및 모사에 관한 연구이다. Frangibolt는 기존 폭발볼트에서 사용하는 분리화약을 사용하지 않고 스마트 소재인 형상기억합금의 온도에 따라 변화되는 미세조직에 따른 응력생성을 이용하여 파이로 장치를 분리시키는 Non Pyrotechnic 장치로써, 실제 Frangibolt노치부에 생성되는 응력의 분포 및 분리거동을 해석함으로써 Frangibolt 설계에 필요한 인자를 파악할 수 있었다. 또한 볼트 설계방법의 최적화를 제시함으로써 향후 다른 종류의 SMA을 이용한분리장치 설계 및 해석 모델에 기초자료를 제공할 수 있을 것이다.

Aerospace applications use pyrotechnic devices with many different functions. Functional shock, safety, overall system cost issue, and availability of new technologies, however, question the continued use of these mechanisms on aerospace applications. Release device is an important example of a task usually executed by pyrotechnic mechanisms. Many aerospace applications like satellite solar panels deployment or weather balloon separation need a release device. Several incidents, where pyrotechnic mechanisms could be responsible for spacecraft failure, have been encouraging new designs for these devices. The Frangibolt is a non explosive device which comprises a commercially available bolt and a small collar made of shape memory alloy (SMA) that replace conventional explosive bolt systems. This paper presents the modeling and simulation of Frangiblot by the change of bolt size and notch geometry. This analysis may contribute to improve the Frangibolt design.

From AC analysis results utilizing a 2-dimensional device simulator, we extracted an AC-equivalent circuit of a grounded-gate NMOS (ggNMOS) electrostatic discharge (ESD) protection device. The extracted equivalent circuit is utilized to analyze the effects of the parasitics in a ggNMOS protection device on the characteristics of a low noise amplifier (LNA). We have shown that the effects of the parasitics can appear exaggerated for an impedance matching aspect and that the noise contribution of the parasitic resistances cannot be counted if the ggNMOS protection device is modeled by a single capacitor, as in prior publications. We have confirmed that the major changes in the characteristics of an LNA when connecting an NMOS protection device at the input are reduction of the power gain and degradation of the noise performance. We have also shown that the performance degradation worsens as the substrate resistance is reduced, which could not be detected if a single capacitor model is used.

A valve-less electro-hydraulic servo steering device (short: VSSD) for ships was chosen as a study object, and its mathematic model of hydraulic shock was established on the basis of flow properties and force balance of each component. The influence of system structure parameters, changing rate of motor speed and external load on hydraulic shock strength was simulated by the method of numerical simulation. Experiment was designed to test the hydraulic shock mathematic model of VSSD. Experiment results verified the correctness of the model, and the model provided a correct theoretical method for the calculation and control of hydraulic shock of valve-less electro-hydraulic servo steering device.

IGBT devices have the best features of both power MOSFETs and power bipolar transistors, i. e., efficient voltage gate drive requirements and high current density capability. The interaction of the IGBT with the load circuit can be described using the device model and the state equation of the load circuit. The protection circuit requirements are unique for the IGBT and can be examined using the model.

In this thesis, the impact analysis for the shunting procedure using the dynamic buffer characteristics of the coupler was developed. In this study, each car was modeled as one dimensional element by using the equivalent system. After the impact, the slip exists only between wheel and rail in the braked trainset. For this analysis the analysis code named the POTAS-MSM (Power Transmission Analysis Software Multi Slip Mechanism) which was developed for the numerical analysis of dynamic system is developed. The validation of this analysis was proven by comparing the numerical results with the results of world-famous S company which is located in Europe.

The IGBT(Insulated Gate Bipolar Transistor) is a power semiconductor device that has gained acceptance among power electronic circuit design engineers for motor drive and Power converter applications. The device-circuit interaction of power insulated gate bipolar transistor for a series-inductor load, both with and without a snubber are, simulated. An analytical model for the transient operation of the IGBT is used in conjunction with the load circuit state equations for the simulations.

In this paper, to implement the electrical equivalent modeling of powder electroluminescent device, capacitate equation of device was chosen. The conventional structure device which have dielectric and phosphor layer between electrodes, and the single emission structure device which means that dielectric and phosphor were mixed between electrodes, were investigated. As a result, it was possible to make the equation that is transferred capacitance to phosphor layer, and using measured brightness efficiency and conductivity of devices was calculated.

The modeling circuit becomes more important in developing various magnetic devices regarding the fact that the competitive architecture and circuitry should be developed simultaneously. In this paper, we introduce a modeling circuit for hysteresis characteristic of a magnetic device, which is a major characteristic in the spin dependent magnetic material. This transistor-level model is conspicuous in that it can be usefully embodied in real circuits rather than conventional SPICE models are only for simulations.

본 연구에서는 ‘분자운동과 상태변화’의 개념을 학습하는 데에 필요한 미시적 입자 개념을 스마트 기기를 활용한 모델링 활동으로 학습할 수 있도록 모델링 활동 도구와 활동 과제를 개발하고 중학교 1학년 학생들에게 적용하여 그 효과를 분석하였다. 연구 결과 스마트 기기를 활용한 모델링 활동 수업을 한 집단은 교과서에 따른 수업 집단에 비해 과학적 모델에 대한 긍정적 인식정도가 전반적으로 증가하였다. 모델의 다양성, 모델의 설명적 도구, 모델의 유용성, 모델의 잠정성 영역에서 인식이 개선되었는데, 이는 스스로 근거를 찾고 표상으로 나타내고 현상을 설명하는 모델링 과정을 연습한 결과, 모델의 본성, 유용성, 모델의 목적, 모델의 이점과 제한점 등을 이해한 것으로 분석된다. 개념 성취도 검사를 통해 통제 집단에 비해 스마트 기기를 활용한 모델링 활동 수업을 한 집단의 개념 이해가 효과적인 것으로 나타났다. 또한 학생들은 모델링 활동을 수행하며 학습내용을 성취함과 동시에 오개념을 수정하는 과정을 거쳤다. 이러한 수정 과정에는 동료 친구들과의 모델링 활동 내용 공유와 교사의 피드백이 작용한 것으로 분석된다. 또한 학생들의 스마트 기기 활용 학습에 대한 인식을 조사한 결과, 수업 처치가 학생의 스마트 기기에 대한 선호도, 학습 흥미도, 학습 유용도 등에 효과적으로 작용했다. 스마트 기기를 활용한 수업이 좋은 이유로는 ‘흥미로운 과학 활동’, ‘자기주도적 학습’, ‘친구 및 교사와의 학습내용 공유’ 등을 꼽았다.

In this study, the modeling learning tool and items were developed and applied to analyze the effect modeling activities using smart devices for learning the concept of 'molecular movement and phase change'. As a result of the study, in the middle school 1st graders, the group of smart device modeling activity class showed an overall increase of positive perception of model as compared with the traditional group. Their perceptions were improved in the areas of ‘Models as multiple representation’, ‘Models as explanatory tools’, ‘The uses of scientific models’, ‘The changing nature of models’. Through the conceptual achievement test, it was found that the concept understanding of the group of smart device modeling activity class was more effective than the traditional instruction group. In addition, Students also underwent a process of correcting misconceptions during modeling activities. The reason for this revision process is due to the sharing of modeling activities with peers and the feedback from teachers. As a result of studying the perception of ‘students use of smart devices in science education', students cited 'interesting science activities', 'self-directed learning', and 'sharing modeling activities with friends’, which are good reasons to use smart devices in the science education.

Double Injection(DI) switching devices consist of PS0+T and nS0+T contact separated by a nearly intrinsic semiconductor region containing deep trap. The equation set for DI switching device simulation by FEM is proposed. The existance of deep trap requires the modification of conventional equation set. So recombination rate equation is modified and a new equation is included in the equation set which conventionally consists op Poisson equation and current continuity equation. Consequently, the modeling equation set, which is proposed in this paper, can be applied to other semiconductor devices with trap.