• The Journal of the Convergence on Culture Technology
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• v.8 no.6
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• pp.41-48
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• 2022

The purpose of this study is to compare the meaning of the experience of robot play in the free play time of 5-year-old children in daycare centers with the experience of 5-year-old children in the structural group activities of teachers. To this end, a total of 32 children (15 in the experimental group and 17 in the comparative group) aged 5 were conducted for 1 hour three times a week for 10 weeks. Robots were supported as toys in the classroom of the experimental group, and children in the comparative group freely experienced robot exploration and play during free play time, and children in the comparative group learned the robot's functions and performed structural group activities based on the 2019 Revised Nuri Curriculum national-level curriculum. As a result of analyzing the difference between pre-test and post-test, the use of robots in free play showed a significant effect in creativity and fluency of children, and a significant effect in expression of pleasure in playability. These results suggest that robots are meaningful as play materials in early childhood education, which aims for infant-led free play, and that it is worth studying the robot experiences of children in these free situations in the future.

• 베이커리
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• no.8 s.445
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• pp.148-151
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• 2005

머랭으로 만드는 과자는 바삭바삭 가벼운 식감이 일품이라 여름과자로 딱 제격이다. 머랭의 보송보송한 느낌을 자연스럽게 살려도 좋고 짤주머니에 넣어 앙증맞게 짜주어도 좋다. 요즘에는 탱탱한 '마시맬로'가 인기를 끌기도 한다. 머랭은 가벼운 식감만큼이나 매우 자유스러운 쓰임새의 과자다.

• The Korean Ginseng Research and Industry
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• v.1 no.2
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• pp.3-8
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• 2007

• Journal of the Computational Structural Engineering Institute of Korea
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• v.17 no.1
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• pp.21-30
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• 2004

This study deals with free vibrations of laminated composite structures with a channel section using finite element method. In this paper, the mixed finite element method using Lagrangian and Hermite interpolation functions is adopted and a high-order plate theory is used to analyze laminated composite non-prismatic folded plates with a channel section more accurately for free vibration. The theory accounts for parabolic distribution of the transverse shear stress and requires no shear correction factors supposed in the first-order plate theory. An 32×32 matrix is assembled to transform the system element matrices from the local to global coordinates using a coordinate transformation matrix, in which an eighth drilling degree of freedom (DOF) per node is appended to the existing 7-DOF system. The results in this study are compared with those of available literatures for the conventional and first-order plate theory. Sample studies are carried out for various layup configurations and length-thickness ratio, and geometric shapes of plates. The significance of the high-order plate theory in analyzing complex composite structures with a channel section is enunciated in this paper.

• Journal of the Society of Naval Architects of Korea
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• v.39 no.1
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• pp.8-15
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• 2002

A two-dimensional higher order panel method using B-splines has been developed to overcome the disadvantages of the low order panel method and to obtain more accurate solution. The sources and the normal dipoles are distributed on both the body and the free surface. Instead of applying the upwind finite difference schemes to satisfy the linearized free surface and the radiation condition, the derivatives of the basis functions of the B-splines are directly applied to the linearized free surface condition. Numerical damping in the Dawson's method are avoided in the Present computations. In order to validate the present method, numerical computations are carried out for a submerged cylinder and a two-dimensional hydrofoil steadily moving beneath a free surface. The numerical results show that fast convergence and better accuracies have been achieved by the present method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.7
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• pp.1418-1423
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• 2004

A legged robot is friendly to human because it is resemble to human. And the robot can obtain support points freely because it has high degree of freedom for several joint as compared with a wheeled robot. Also the robot can create the relative position at desired position between support position and robot. The joint of robot cu used as manipulator. On the contrary the mechanism of robot is complicated to have many joint and moving speed is lower than wheeled robot. Also the legged robot is needed a special control not to fall on the ground because the robot is easy to vibrate when it is moving. The 4 leg structure is the minimum leg numbers not to fall and to realize safety gait continuously. A trot gait is investigated through experiments using a quadruped walking robot named TITAN-VIII.

• Korean Journal of Food Science and Technology
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• v.12 no.3
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• pp.209-215
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• 1980

Proteases from papaya latex were partially purified by ammonium sulfate precipitation and separated into two fractions (Fraction I and II ) by carboxymethyl cellelose column chromatography. Each fraction, mixture of the two fractions, and crude extract of the papaya latex at pH 7.0 were inactivated at the range of $60{\sim}90^{\circ}C$ and thermal properties of the enzymes were investigated. In the thermal inactivation of fraction I, the enthalpy of activation was 89.5 kJ/mol; the entropy of activation, -44.0 J/mol K; the free energy of activation, 104.6 kJ/mol; z-value, $25^{\circ}C$. For fraction II, the enthalpy of activation was 96.5 kJ,/mol; the entropy of activation, -22.0 J/mol K; the free energy of activation, 104.0 kJ/mol; z-value, $23^{\circ}C$. For the mixture of fraction I and II, the enthalpy of activation was 90.9 kJ/mol; the entropy of activation, -38.8 J/mol·K; the free energy of activation, 104.2 kJ/mol; z-value, $24.6^{\circ}C$. For crude extract, the enthalpy of activation was 113.8 kJ/mol; the entropy of activation, 22.0 J/mol·K; the free energy of activation, 106.2 kJ/mol; z-value, $23.2^{\circ}C$. It was indicated that the fraction I was more heat-stable than the fraction II and this suggested that the thermal stability of the proteases in papaya latex is probably due to the fraction I.

• Journal of Navigation and Port Research
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• v.47 no.6
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• pp.305-314
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• 2023

In this study, a mathematical model of a 9.77 G/T small fishing vessel was established based on captive model tests. The powering and manoeuvring performances of the vessel in the harbor and coastal sea were focused on, so captive model tests were conducted up to the full-scale speed of 8 knots. Propeller open water, resistance, and self-propulsion tests of a 1/3.5-scaled model ship were performed in a towing tank, and the full-scale powering performance was predicted. Hydrodynamic coefficients in the mathematical model were obtained by rudder open water, horizontal planar motion mechanism tests of the same model ship. In particular, in static drift and pure yaw tests which were conducted at a speed of 2 to 8 knots, the linear hydrodynamic coefficients varied with the ship speed. The effect of the ship speed on the linear coefficients was considered in the mathematical model, and manoeuvring motions, such as turning circles and zig-zags, were simulated with various approach speeds and analyzed.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.8
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• pp.828-837
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• 2009

Recently, as high-rise buildings increase steeply, sub-structures of them are often supported on elastic foundation(in a case of pasternak foundation or winkler foundation). And there are many machines in sub-structures of buildings and slabs of sub-structures are affected by vibration which they make. This paper deals with vibration of plates on elastic foundation. Machines on plates are considered as concentrated mass. This paper has the object of investigating natural frequencies of tapered thick plate on pasternak foundation by means of finite element method and providing kinetic design data for mat of building structures. Free vibration analysis that tapered thick plate with Concentrated Masses in this paper. Finite element analysis of rectangular plate is done by use of rectangular finite element with 8-nodes. In order to analysis plate which is supported on pasternak foundation. The Winkler parameter is varied with 10, $10^2$, $10^3$ and the shear foundation parameter is 5, 10. This paper is analyzed varying thickness by taper ratio. The taper ratio is applied as 0.0, 0.25, 0.5, 0.75, 1.0. And the Concentrated Mass is applied as P1, Pc, P2 respectively.

• The Journal of Korea Robotics Society
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• v.8 no.1
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• pp.8-19
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• 2013

One of the important issues for structural and electrical specifications in developing a robot is to determine lengths of links and motor specifications, which need to be appropriate to the purpose of robot. These issues become more critical for a gait rehabilitation robot, since a patient wears the robot. Prior to developing an entire gait rehabilitation robot, designing of a 1DOF assistive knee joint of the robot is considered in this paper. Human gait motions were used to determine an allowable range of knee joint that was rotated with a linear type actuator (ball-screw type) and links. The lengths of each link were determined by using an optimization process, minimizing the stroke of actuator and the total energy (kinetic and potential energy). Kinetic analysis was performed in order to determine maximum rotational speed and maximum torque of the motor for tracking gait trajectory properly. The prototype of 1 DOF assistive knee joint was built and examined with a impedance controller.