• Membrane and Water Treatment
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• v.11 no.4
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• pp.237-245
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• 2020

The effects of the mixed two solvents, Dimethylacetamide (DMAc) and Dimethylformamide (DMF), and Polyethylene glycol (PEG) and Polyvinylpyrrolidone (PVP) as additives on performance of Polyvinylidene fluoride (PVDF) membranes were studied. Initially, PEG200 was used as a primary additive at fixed percentage of 5% wt. PVP was then blended with PEG200 in different concentrations. PVDF and DMAc were used as polymer and solvent in the casting solutions, respectively. To control the diffusion rate of PVP in the presence of PEG200 and PVP blend, mixtures of DMAc and DMF were used as the mixed solvent in the casting solutions. Asymmetric PVDF membranes were prepared via phase inversion process in a water bath and the effects of two additives and two solvents on the membrane morphology, pure water flux (PWF), hydrophilicity and rejection (R) were investigated. Attenuated Total Reflection Fourier Transform Infrared Spectra (ATR-FTIR) analysis was used to show the residual PVP on the surface of the membranes. Atomic Force Microscopy (AFM) was utilized to determine roughness of membrane surface. The use of mixed solvents in the casting solution resulted in reduction of PVP diffusion rate and increment of PEG diffusion rate. Eventually, PWF and R values reduced, while porosity and hydrophilicity increased.

• Journal of the Korea Furniture Society
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• v.19 no.5
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• pp.341-349
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• 2008

This study intends to analyze the importance of design on the basis of the children' emotion, by instancing the child-oriented furniture that contributes to the healthy growing and emotion-development of children. This means the reflection of the will trying to see the main point of design for the child-oriented furniture and it's possibility from another new standpoint. It will be understood how far the furniture influences the children and for that the furniture among others for the preschool children having playing & leaning functions is taken as an object of the study. The scope of study is the child-oriented furniture having playing & learning functions that has been presented for displaying as well as for a commercial use, since 2005. The attempt to find objective factors working positively for the emotion- & behavior development of children through seeking a new design of the child-oriented furniture for playing & learning is for emphasizing the importance of the emotional function, not only the primary function of furniture, at designing the child-oriented furniture. The combination between applications of the specialized material for child education & studies, therefore, has to be handled more importantly. The child-oriented furniture for playing & leaning that stimulates a healthy growing of child not only physically, also emotionally should be constantly and more deeply specialized on child education and design aspects.

• Journal of Sensor Science and Technology
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• v.13 no.2
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• pp.85-89
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• 2004

This paper represents the development of high sensitivity photo-sensor for the fluorescence detection in the integrated biological analysis system. The finger-type PIN photodiodes were fabricated as the photo-sensor, and had a high sensitivity ($I_{light}/I_{dark}$ = 8720). The interference filter consisted of $TiO_{2}$ and $SiO_{2}$ was directly deposited on the photodiodes. Deposited filter with 95.5% reflection under 532 nm and 98% transmission over 580 nm exceedingly decreased the magnitude of background signal in the detection. The PDMS micro-fluidic channels are bonded on the photodiode by $O_{2}$ plasma treatment. The detection current was proportional to two primary parameters (light intensity, concentration), and the on-chip detection system could detect fluorescence signals down to 100 nM concentration (LOD = Limit of detection of rhodamine).

• Journal of The Korean Association of Information Education
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• v.6 no.3
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• pp.247-255
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• 2002

The importance of Information Technology practical use is embossed and grounding education for this was introduced from first-year student in primary school. This study is to design and implement new set of study program that can minimize individual variation in learning, analyzing the grounding education in Information and Communication. Herein basic stuff is selected for the lower grader at Elementary School and for the Courseware design, here introduced Perfect study strategy that makes use of the formative evaluation and feed back, aiming at perfect study. And also the diversified presentation of study materials with the use of multimedia can enhance the student's learning awareness. In faithful reflection of it, individual student's progress and interested in learning is incorporated into the designing the Courseware.

• Education of Primary School Mathematics
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• v.10 no.2
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• pp.77-110
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• 2007

This study attempted to investigate how to students show high-level mathematical thinking in math classes. This paper describes how to setup the task for lead to a high - level of thinking out students and what efforts are required while a teacher tried to maintaining students's high-level cognition during the tasks implemented. The researcher as teacher analyzed the tasks of length measurement unit in 2-Ga elementary math textbooks, modified and created math tasks demanded students' high-level cognition, made instruction plans, and implemented those tasks maintaining the levels of cognitive demand of tasks. After that, the researcher reflected and analyzed the levels of cognitive demand of tasks of instruction and factors that cause to change intended high-level cognitive demand. After reflection, second roof of action research was conducted to 2-Na length measurement unit. This paper includes those results and reflections of practitioner.

• Education of Primary School Mathematics
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• v.6 no.1
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• pp.41-54
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• 2002

The purpose of this study is to find out what mathematical situation means, how to pose a meaningful situation and how situation-centered teaching could be done. The obtained informations will help learners to improve their math abilities. A survey was done to investigate teachers' perception on teaching-learning in mathematics by elementary teachers. The result showed that students had to find solutions of the textbook problems accurately in the math classes, calculated many problems for the class time and disliked mathematics. We define mathematical situation. It is artificially scene that emphasize the process of learners doing mathematizing from physical world to identical world. When teacher poses and expresses mathematical situation, learners know mathematical concepts through the process of mathematizing in the mathematical situation. Mathematical situation contains many concepts and happens in real life. Learners act with real things or models in the mathematical situation. Mathematical situation can be posed by 5 steps(learners' environment investigation step, mathematical knowledge investigation step, mathematical situation development step, adaption step and reflection step). Situation-centered teaching enhances mathematical connections, arises learners' interest and develops the ability of doing mathematics. Therefore teachers have to reform textbook based on connections of mathematics, other subject and real life, math curriculum, learners' level, learners' experience, learners' interest and so on.

• Korean Journal of Materials Research
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• v.4 no.5
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• pp.516-523
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• 1994

The interfacial coherency of metal organic chemical vapor deposition grown InGaAsP/InP heterostructure wafers was examined and their influences on the optoelectronic properties were investigated in this study. (400) symmetric and (511) asymmetric reflections were employed to measure the lattice coherency. Existence of misfit dislocations was examined by x-ray topography and reverified by photoluminescence (PL) imaging. PI, measurements were performed, and higher PL intensity was obtained for elastically strained samples and lower intensity for plastically deformed samples. The highest PL intensity was obtained for the sample lattice matched at the growth temperature. PL full-width at half maximum (FWHM) was found to depend on the degree of lattice mismatch. A correlatior between x-ray FWHM and PL intensity was empirically established. The results presented demonstrate that the interfacial coherency is of primary significance in affecting the optoelectronic properties through elastic strain and plastic deformation.

• International Journal of Computer Science & Network Security
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• v.21 no.6
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• pp.151-155
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• 2021

The article is based on a model, in the context of which there are two fundamental building blocks of basic library skills and skills in the use of information technology. The former are formed within the framework of educational programs for users of academic libraries, the latter are formed within the framework of initiatives such as the European Computer Driving License. Between the basic and the highest levels of the concept of "information literacy" there are seven heading skills and attributes, the repeated practice of which leads from the position of a competent user to an expert level of reflection and critical awareness of information as an intellectual resource. Freshmen will likely be at the beginning of the arrow, probably practicing only the first four skills, while graduate students and young scientists will be closer to the end and will use seven skills.

• Journal of Korean Port Research
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• v.12 no.1
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• pp.75-86
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• 1998

To design a coastal structure in the nearshore region, engineers must have means to estimate wave climate. Waves, approaching the surf zone from offshore, experience changes caused by combined effects of bathymetric variations, interference of man-made structure, and nonlinear interactions among wave trains. This paper has attempted to find out the effects of two of the more subtle phenomena involving nonlinear shallow water waves, amplitude dispersion and secondary wave generation. Boussinesq-type equations can be used to model the nonlinear transformation of surface waves in shallow water due to effect of shoaling, refraction, diffraction, and reflection. In this paper, generalized Boussinesq equations under the complex bottom condition is derived using the depth averaged velocity with the series expansion of the velocity potential as a product of powers of the depth of flow. A time stepping finite difference method is used to solve the derived equation. Numerical results are compared to hydraulic model results. The result with the non-linear dispersive wave equation can describe an interesting transformation a sinusoidal wave to one with a cnoidal aspect of a rapid degradation into modulated high frequency waves and transient secondary waves in an intermediate region. The amplitude dispersion of the primary wave crest results in a convex wave front after passing through the shoal and the secondary waves generated by the shoal diffracted in a radial manner into surrounding waters.

• Korean Medical Education Review
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• v.26 no.1
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• pp.55-69
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• 2024

Amid the increasing interest in medical humanities education, this study developed a medical humanities course that utilized design thinking to foster creative thinking, problem-solving, and collaboration skills that pre-medical students should possess. The course's efficacy was assessed by evaluating improvements in core design thinking skills. The present study was conducted among 83 first-year medical students after planning and implementing a design thinking course. The reflection journals written by students along the course of the class were examined using the template analysis technique to evaluate the effectiveness of the class. The study's primary findings showed the successful development of step-by-step medical humanities education content utilizing design thinking and its practical implementation in a class. Moreover, the course improved students' core design thinking skills effectively, and in a balanced way. These results illustrate the effective application of design thinking in medical school through a medical humanities course. These findings indicate that a medical humanities course can help medical students showcase their abilities to collaborate and solve problems in the real world. This paper suggests the need for further research to develop a curriculum that integrates design thinking and investigate the relationship between medical students' core competencies and design thinking-based courses.