This study aim is analysis device development for design of experiment with calcium chloride relation used a hardener to search cause of product crack, product reliability improvement building data-base program for computer system of mixture rate, product improvement, and new product development.

A combination steering system was designed to provide the flexibility in controlling the steering wheel in fishing operations of the inshore and coastal fishing vessels. The designed steering system basically is consisted of three driving units, such as a electrically driven hydraulic pump unit with a solenoid control valve, a DC motor driven hydraulic pump unit and a manually driven hydraulic pump unit, and two controllers to provide remote steering on the deck, respectively. The steering torque was measured and analyzed to investigate the dynamic performance of the developed steering system. The steering system showed excellent linearity between the working pressure of cylinder and the torque of rudder post in case of increasing in rudder angle from 5˚ to 35˚ that is, the steering torque increased from 10.4 kgf·m to 105.3 kgf·m and then the working pressure of cylinder fluctuated from 6.3 kgf/cm super(2) to 16.4 kgf/cm super(2). The steering time of 3.2 sec in remote hydraulic steering by the on/off solenoid valve control was much faster than 13.2 sec in the manual steering by the helmsman and 11.6 sec in the electric steering by a DC motor, and then it was verified that operation of one unit does not affect other units in combination steering system in any way. Furthermore, the developed steering system can be remotely controlled in multiple stations of the deck during the fishing operation and the automatic pilot steering unit can be used to add hydraulic steering.

The electro-hydraulic servo winch system built in a automatic tension control equipment was designed with a latent need for an advanced system in fishing operations of the inshore and coastal fishing vessels. In order to keep the constant tension condition of warp under loading, a tension control circuit was added to the servo winch system.The dynamic performance in the open loop behaviour of the designed winch system was investigated and its applicability was tested for various possibilities of load using a load generator especially developed in order to this study.The mechanical characteristics of this system is different from that of a conventional type, that is, the tension, length, line speed and drum revolution can be automatically controlled by the information from various sensors, such as torque, rpm and pressure transducers. from the experiment results, it was verified that the servo winch system has very good output and tracking behaviour for the control input signals in different operating conditions though overshoot of out 8% in the transient characteristics of torque under the load though a overshoot of about 8% in the transient characteristics of torque under the load condition can be observed when the opening of servo valve, adjustable by the input voltage between - 10 V up to 10 V, changed suddenly.Consequently, the improved fishing winch system can be effectively used as the automatic shooting and hauling equipment of low cost for small inshore and coastal fishing vessels which engage in net fishing.

As we become an aging society, the number of elderly patients continues to increase. Pressure sores that can easily occur in patients with trauma cause serious socio-economic problems. In general, prevention of bedsores through predicting the patient's posture is being developed. Developed method usually use artificial intelligence techniques to estimate the patient’s posture by measured pressure images in the mattress. In this method, it has a problem the reduction of estimation accuracy when posture of patient is changed. Therefore, it is necessary to use the filter of pressure images in the position transition of patient. In this paper, we propose an algorithm to predict the patient's posture, and an algorithm to reduce the ambiguity that can occur in the patient's posture transition section. By obtaining stable data through this algorithm, learning/prediction stability of the neural network can be expected, and prediction performance is improved accordingly. Through experiments, the effectiveness of the algorithm was verified.

In robotic harvesting, a gripper to manipulate the fruits needs to be attached to the robot system. We proposed a flexible robot gripper that can actively respond to the shape of an object such as fruits in the previous work. However, we found that there is a possibility of not being reliably gripped when the object slides during contact with a finger. In this paper, the improved gripper design is proposed to fundamentally solve the problems of the previous gripper. The position of the finger and the maximum closed position are changed, and the design improvement is performed to increase the grip stability by changing the installation angle of the link portion of the finger. Based on the improved design, a modified gripper is fabricated by 3-D printing, and then gripping experiments are performed on spherical object and fruit model object. It is shown that the gripper can stably grip the objects without excessive bending of the finger link of the gripper. The contact pressure between the finger and the surface of the object is measured, and it is verified that it is a sufficiently small pressure that does not cause damage to the fruit. Therefore, the proposed gripper is expected to be successfully applied in harvesting.

De-icing work in highways has been changed from sand and calcium chlorides spreading to pre-wetted salt spreading since 2000s. Recently, the concern on the premature deterioration of concrete structures due to de-icing salts and its counter measurements has been increased. This paper describes the change of de-icing methods and deterioration due to chloride attack and specification of durable concrete.

본 연구는 초등학교 통합교과 교육과정의 실행과정에서 발생하는 문제점을 분석하고 이를 개선하기 위한 방안으로 내러티브와 백워드 설계 2.0 버전을 적용하는데 목적이 있다. 연구자는 초등학교 1학년의 대주제 ‘학교’에 해당하는 ‘학교에 가면’ 단원을 백워드 설 계 2.0 버전과 내러티브를 활용하여 개발하였다. 그 결과, 백워드 설계 2.0 버전과 내러 티브는 교과서 중심의 진도 나가기식 관행, 타당한 이해의 부재, 활동 중심 수업으로 인한 앎의 방식 습득의 어려움 등 통합교과 교육과정 실행의 문제점을 개선할 수 있는 방안으로서의 가능성을 확인하였다.

In this study, it modeled the ground proper to geotechnical site characteristics in Korean urban area, compared geotechnical site characteristics of the selected 158 grounds in Korean urban areas with characteristics of the ground in the western part of the United States and performed earthquake responses to improve the decision method of the design earthquake force. Based on the amplification factor from the analysis results, the response spectra of each ground were developed and analyzed with the design response spectra presented in the seismic design criteria.

In this study, it modeled the ground proper to geotechnical site characteristics in Korean urban area, compared geotechnical site characteristics of the selected 158 grounds in Korean urban areas with characteristics of the ground in the western part of the United States and performed earthquake responses to improve the decision method of the design earthquake force. Based on the amplification factor from the analysis results, the response spectra of each ground were developed and analyzed with the design response spectra presented in the seismic design criteria.

Maintenance costs, depending on the occurrence of deterioration expressway bridges has been increasing at a very rapid rate (approximately 200% increase in the last five years). In order to reduce the damage caused by water leakage and de-icing salt damage, We proposed a design improvement of concrete slab edge.

Due to expansion of service environments for the Jack-up barge, the design of the footing has been improved. In this paper, the structure analysis of the modified spudcan based on DNV-OS-C201 examples was assessed.

Maintenance costs, depending on the occurrence of deterioration expressway bridges has been increasing at a very rapid rate (approximately 200% increase in the last five years). In order to reduce the damage caused by water leakage and de-icing salt damage, We proposed a design improvement of concrete slab edge.

디지털 방사선촬영 기술은 영상 정보를 획득하는 원리에 따라 광도전체를 이용하는 직접 방식과 형광체를 이용하는 간접 방식으로 구분되지만, 모두 다양한 장단점을 내포하고 있다. 이에 본 연구에서는 X-ray 민감도를 개선하고자 형광체 및 광도전체를 병용한 Hybrid형 검출기의 구조에 대한 기초 연구를 수행하였다. 실험 결과, 조사 시간을 30 ms로 고정하고 관전압을 변화할 경우 전체적으로 직접 방식의 구조에서 우수한 민감도가 나타났으나, 조사 시간이 50 ms 이상에서는 Hybrid 구조의 경우가 더 우수한 것으로 나타났다. 이는 임상에서 다양한 검사를 수행할 경우에 일반적으로 50 ms 이상의 조사시간을 이용한다는 점에서 충분한 연구적 가치를 가질 것으로 사료된다.

Chloride attack, one of the reasons for early deterioration of concrete, is a phenomenon where detrimental ions such as chlorine ion penetrate into concrete from outside to diffuse and corrode the steel rebar, greatly deteriorating the durability of RC members or structures. Sources of chloride attack can be divided into the direct / indirect influence caused by seawater or its splash in the maritime environment and the de-icing salts used for the purpose of thawing the ice on the wintry road. Most notably, the usage of de-icing salts is essential for the safety of drivers and smooth traffic flows in expressways. However, they also quicken the deterioration of concretes, necessitating the countermeasures for the problem. This paper discusses the early deterioration and measurements of RC Structures under de-icing salts environments.

해안항만 분야 문제해결을 위하여 여러 가지 방법이 적용되어 왔다. 특히 전통적으로 수행되어온 방법으로는 수리모형실험과 수치해석을 들 수 있다. 특히 수치해석의 경우 컴퓨터의 발전과 더불어 수치기법의 다양화, 3차원 해석, 계산영역의 확대, 다양한 변수의 적용 등 많은 발전이 이루어져 왔다. 수리모형실험에 있어서도 전자장비의 발전과 더불어 조파장치의 발달, 첨단계측장비의 개발 등 많은 개선이 이루어져 왔다. 그렇지만 여전히 수리실험은 원형의 성능을 사전에 파악하고, 또한 지배적인 외력을 대상으로 실험을 실시하여 원형에서의 현상을 미리 예측하고 분석하여 대응방법을 세우는 것이 목적이다. 이러한 수리실험을 수행하기 위해서는 실험목적을 달성하기 위하여 실험장비 적용 및 한계, 실험자의 적절한 경험이 필요하다. Hughes(1993)은 실험자의 경험에 의한 수리모형의 설계가 실험의 단계에 있어 가장 중요하다고 제시하고 있다. 본 발표에서는 기존 연구자료(Hughes, 1993; HydralabⅢ, 2011)에서 제시하고 있는 기본적인 수리실험의 적용한계 및 장비구성 등에 대하여 기술하며, 국내외 대표 실험인프라에 대하여 소개하고자 합니다. 그리고 특히 유럽내 Hydralab의 사례를 바탕으로 국내 해안항만 실험 연구분야 및 실험인프라의 활성화에 대한 제언을 하고자 합니다.

최근 지진관측 이래 최초로 초진, 본진, 여진을 포함한 연속지진이 발생하는 등 한반도 인근에 지진 발생의 가능성 증가하고 있다. 철도의 경우 고속화, 중량화가 진행됨에 따라 지진에 따른 발생 가능 피해의 규모도 커지고 있는 상황으로 적절한 내진 및 면진 설계를 통한 안전성 증대가 시급한 상황이다. 특히 고속철도의 경우 지진 시 적절한 대책 수립이 되어 있지 않을 경우 지진 재해에 대한 적절한 대응 방안이 수립되어 있지 않을 경우 엄청난 인적/물적 피해를 초래할 수 있는 상황이다. 이 논문에서는 최근 일반 및 고속철도 시설물에 대한 내진 보강 현황과 내진·면진 설계와 관련한 연구 동향을 고찰하고 개선 방안을 제시하였다. 또한 최근 연구가 진행 중인 지진 관측 시스템과 대응 시스템과 관련하여 해외의 사례를 분석하고 지진에 대한 보다 효율적인 대처 방안을 제시하였다. 특히 지진 시 더 큰 인적·물적 피해를 초래할 수 있는 전력, 신호, 통신 등 시스템설비 및 역사 지붕, 내장재 등 비구조재에 대한 내진기준 및 성능평가 기법에 대한 개발 필요성도 포함하여 지진으로 인한 실질적인 피해를 최소화할 수 있는 방안을 제시하였다.