• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.04a
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• pp.23-26
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• 2003

Solid-state extrusion technique was employed for the improvement of mechanical properties of polylactic acid (PLLA) widely used as biodegradable internal fixation devices currently. Cylindrical billets were machined out from the vacuum compression-molded PLLA to have various diameters, and solid-state extrusion of the billets was performed at various drawing rates and at the extrusion temperature of $130^{\circ}C$. Throughout the whole processes the decrease in molecular weight was significantly suppressed to be about $10\%$. Flexural modulus and strength of PLLA increased up to 8.3 GPa and 221 MPa, respectively. Studies on the orientation and crystallinity of extruded PLLA could reveal the effects of billet morphology, draw ratio, and drawing rate on the flexural strengths of PLLA.

• Journal of the Korean Society of Earth Science Education
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• v.8 no.1
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• pp.25-34
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• 2015

The objective of this study is to clarify how high school students recognize the mental model of the global environment and how they conceptualize the environment. Using the drawing and interview, 25 high school students participated in the survey and were asked to visualize the environmental elements of the global environment and describe the environment they portrayed. The dominant mental model in the present was Mental Model 3: the environment as a place impacted or modified by human activity. Yet, the partial mental model in the future was Mental Model 2: the environment as a place that supports human life. The implications to environmental science education are explored.

• Journal of Korea Multimedia Society
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• v.18 no.1
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• pp.71-80
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• 2015

Many researches have been studied to overcome the weak points in authentication schemes of mobile devices such as pattern-authentication that is vulnerable for smudge-attack. Since random-pattern-lock authenticates users by drawing figure of predefined-shape, it can be a method for robust security. However, the authentication performance of random-pattern-lock is influenced by input noise and individual characteristics sign pattern. We introduce an optimization method of user input direction to increase the authentication accuracy of random-pattern-lock. The method uses the likelihood of each direction given an data which is angles of line drawing by user. We adjusted recognition range for each direction and achieved the authentication rate of 95.60%.

• Physical Therapy Korea
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• v.19 no.4
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• pp.1-7
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• 2012

This present study investigated the effects of the abdominal drawing-in maneuver (ADIM) and chin tuck (CT) on middle thoracic erector spinae, lower thoracic erector spinae, and lumbar erector spinae muscle activity during three prone thoracic extension (PTE) exercises. Twelve healthy subjects performed preferred PTE, ADIM PTE, and ADIM-CT PTE. Surface electromyography was used to collect data on the muscle activity of dominant middle and lower thoracic erector spinae muscles and the lumbar erector spinae. Middle and lower thoracic erector spinae muscle activity significantly increased when ADIM and CT was performed (p<.05). However, lumbar erector spinae muscle activity significantly decreased in ADIM PTE compared to preferred PTE (p=.017) and significantly increased in ADIM-CT PTE compared to ADIM PTE (p=.004). In conclusion, ADIM-CT PTE effectively increased middle and lower thoracic erector spinae muscle activity, and ADIM PTE decreased lumbar erector spinae muscle activity. Hence, ADIM PTE could be a recommended exercise maneuver to strengthen thoracic erector spinae without over activation of lumbar erector spinae.

• Journal of The Korean Association For Science Education
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• v.27 no.3
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• pp.190-200
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• 2007

In this study, we analyzed the uses of external representations in material units of 7th grade science textbooks developed under the 7th National Curriculum on the basis of theories and research results on learning with multiple representations. The results revealed that the frequencies of microscopic external representations were higher than those of macroscopic and symbolic external representations. The external representations with drawing and/or writing were presented more frequently than those without drawing and/or writing. Furthermore, the external representations were rarely presented on the basis of the principles (e.g., personalization principle) and/or theories (e.g., dual coding theory, cognitive load theory, and social constructivism theory) for effective uses of the external representations in learning with multiple representations. Educational implications are discussed.

• Genomics & Informatics
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• v.7 no.3
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• pp.171-174
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• 2009

The characteristics of metabolic pathways make them particularly amenable to layered graph drawing methods. This paper presents a visual Java-based tool for drawing and annotating biological pathways in two- and a-half dimensions (2.5D) as an alternative to three-dimensional (3D) visualizations. Such visualization allows user to display different groups of clustered nodes, in different parallel planes, and to see a detailed view of a group of objects in focus and its place in the context of the whole system. This tool is an extended version of J2dPathway.

• Textile Coloration and Finishing
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• v.28 no.4
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• pp.231-238
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• 2016

We investigated the evolution of crystal formation as a function of drawing ratio in poly(1,4-diaminobutane-co-adipic acid-co-${\varepsilon}$-caprolactam-co-diethylenetriamine)(nylon 466T) copolymer formed by four monomers, i.e 1,4-diaminobutane, adipic acid, ${\varepsilon}$-caprolactam, diethylenetriamine(DETA), using synchrotron X-ray scattering measurement. In case of pristine(as spun) nylon 466T fiber, it was consisted with unoriented nylon $6{\alpha}$ and unoriented nylon $46{\alpha}$ phases. As increase the drawing ratio, unoriented nylon $6{\alpha}$ was transformed to oriented ${\gamma}$ phase, while unoriented nylon $46{\alpha}$ changed to oriented $46{\alpha}$ phase. The effect of the addition of DETA was not observed in the pristine fibers. However, DETA affected to restrict the formation of crystals at the maximum drawing condition, and as a result it had a role to increase the moisture regain.

• Journal of the Korean Society of Physical Medicine
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• v.11 no.1
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• pp.83-91
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• 2016

PURPOSE: There are several methods, such as the abdominal drawing-in maneuver (ADIM), maximal expiration (ME), and Kegel exercise, to strengthen the core muscles. However, to date no study has been conducted to compare the effects of the ADIM, ME, and Kegel exercise on the transverses abdominis (TrA), internal oblique (IO), external oblique (EO), and pelvic floor muscles (PFMs). The purpose of this study was to find out which of the three aforementioned exercises is most effective for contracting the core muscles. METHODS: The thickness of the TrA, IO, EO and PFMs was measured by ultrasonographic imaging during the ADIM, ME and Kegel exercise in 34 healthy participants. RESULTS: There was the significant difference between ADIM and Kegel exercise in the thickness of the TrA (p<0.05). There were the significant differences between ADIM and ME and between ME and Kegel exercise in the thickness of the IO and PFM (p<0.01). There was no significant activation in the thickness of the EO (p>0.05). Measurement reliability was assessed using intraclass correlation coefficients (ICC) and the standard error of measurement (SEM). An ICC value of >0.77 indicated that reliability measurements was good. CONCLUSION: Kegel exercise was the most effective exercise for the TrA and the PFM, and ME was the most effective exercise for the IO muscles.

• Physical Therapy Korea
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• v.16 no.1
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• pp.10-17
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• 2009

The aim of this study was to investigate the effect of abdominal drawing-in maneuver (ADIM) on peak exploratory flow (PEF), forced exploratory volume in 1 second ($FEV_1$), and low back pain during forced expiration. Twenty-two subjects (14 subjects in experimental group, 8 subjects in control group) participated in this study. The stabilizer was used for ADIM training for five consecutive days. Vitalograph PEF/$FEV_1$ DIARY and visual analogue scale (VAS) were used to determine forced expiratory pulmonary function and low back pain, respectively. Independent t-test and analysis of covariance were used for statistical analysis with a significance level of .05. The findings of this study were as follows: 1) There were no significant differences of ADIM effect on PEF and $FEV_1$ between experimental group and control group. 2) There was a significant pain reduction in experimental group with ADIM. 3) PEF and $FEV_1$ increased significantly in the fifth day compared with the first day pre-exercise baseline. Therefore, it is concluded that ADIM was effective in improving PEF and $FEV_1$, and reducing VAS during forced expiration in patients with chronic low back pain.

• Journal of the Korean Society of Earth Science Education
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• v.1 no.1
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• pp.111-118
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• 2008

This study is aimed at analyzing earth conception the nine pre service teachers who are majoring in earth science education and classifying a special feature from the ontological categories. Open ended questionnaires and semi structured interviews which meant to contribute to identifying ontological categories of concepts involving study area were designed. Pre service teachers' ontological category about earth conception most showed to dynamic and proto process. In the results show that many pre service teachers recognize simply the conception to a material, a condition and a conversion of the state changing. Most of the pre service teachers show their intermediate understanding level about the earth inner construction according to the analyzed results of the drawing tasks and interviews. The main alternative conceptions show them through a definition of the plate, a wording definition between lithosphere and asthenosphere, a feature of the plate boundary, a heat convection in the earth inner, the earth inner heat source, the earth inner structure, a physical feature of the mantle.