• Textile Coloration and Finishing
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• v.31 no.2
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• pp.107-117
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• 2019

In case of pure rubber materials, the initial quality of the rubber materials would be excellent, however, the durability against external impact might be poor. In order to overcome the relatively low durability, textile cord could be employed with silicone rubber. We have studied the improvement of heat-resistant adhesion properties of silicone adhesives between silicone rubber and PET fibers by applying various conditions including dip solution recipe. The silicone rubber used was a platinum catalyst curing type and platinum catalyst type silicone adhesive was used as an adhesive to obtain an optimum adhesive force. Furthermore, the bonding mechanism between silicone and PET fiber was established.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.8
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• pp.52-59
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• 2021

In this study, we experimentally evaluated the mechanical properties and geometric form accuracy in FDM 3D printing processes based on the printing direction, building direction, and layer thickness. The specimen test results showed that the tensile strength increased by over 33% in the printing direction compared to the direction perpendicular to printing and the tensile strength becomes larger as the layer thickness decreased. Furthermore, the tensile and impact strengths in the building direction were significantly reduced due to the difference in the interlayer joining and bonding strengths of the fused material. Additionally, shrinkage of the material due to phase change induced curl distortion especially in thin and long 3D-printed products, which increased as the layer thickness increased.

• Bulletin of the Korean Chemical Society
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• v.16 no.3
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• pp.238-243
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• 1995

A pulsed molecular beam source having short pulse duration (typically 70 ${\mu}s)$ and narrow velocity distribution (${\Delta}$v/v=8% for helium) has been costructed utilizing a commercial fuel injector. Beam characteristics of helium and ammonia seeded in helium expansions are accomplished by the use of an electron impact time-or-flight mass spectrometer. The comparisons between experimental data and theoretical calculations show that the proper beam speed is important to predict the evolution of stream temperature and valve shutter function. The decreasing tendency of pulse duration with increasing cluster size leads to the conclusion that the cluster beam property is described as a function of cluster mass and disinct cluster temperature.

• Journal of the Korean Society for Precision Engineering
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• v.11 no.2
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• pp.134-140
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• 1994

Numerical caiculations are made in order to find a possible relation between the J-integral and the crack mouth opening displacement(CMOD) in dynamic nonlinear fracture experiments. Both elastic-plastic and elastic-viscoplastic materials are considered at different impact velocities. The J-integral may be estimated from the crack mouth opening displacement which can be measured directiy from photographs taken during dynamic experiments.

• International Journal of High-Rise Buildings
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• v.12 no.2
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• pp.137-143
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• 2023

The use of Engineered Wood Systems (EWS), especially mass-timber, as a structural alternative or complement to steel and concrete is gaining interest and acceptance across different sectors of architecture, engineering, and construction, including in high-rise buildings. Focussing on the Australian context, this study examines the levels of adoption and barriers to using timber as a primary structural material in multi-storey buildings. Data collected from semi-structured interviews with stakeholders at the forefront of adoption in structural design, construction, and property development indicates that timber in multi-storey projects in Australia still faces industry-wide challenges. Designers' awareness and attitudes towards timber adoption are generally positive and suitable for flagship projects, including tall buildings, but for enduring and widespread impact, long-term investment in education within and outside the range of stakeholders already committed to promoting timber adoption is needed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.185-186
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• 2023

In the production of high-strength concrete of 80 MPa or more, silica fume is widely used as a binder to ensure the strength safety and pumpability of concrete. The bulk density of silica fume is an important physical property that can have a significant impact on the performance of concrete. Therefore, Understanding the effect of silica fume density on the physical properties of concrete and selecting the appropriate material with the correct density is crucial to ensuring optimal performance in construction projects.

• Journal of Technology Innovation
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• v.21 no.2
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• pp.319-354
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• 2013

As creative economy gets attention, the capabilities of transforming creative ideas into intellectual property and utilizing it commercially have become important than ever before. Korea is lack of the capabilities of utilizing intellectual property compared to those of accumulating it. This paper focuses on the strategic implication of an injunctive relief, which has a far-reaching impact on firms' business strategies as well as national industrial competitiveness because losers in lawsuits are expelled from markets. It analyzes the Samsung-Apple global IP lawsuits about smartphones and tablet PCs, which have expanded into 9 countries since 2011 when the Apple filed the IP lawsuit against Samsung in the US for the first time. In particular, this paper analyzes the requirements to get the permanent injunctive relief in the lawsuits of intellectual property from reviewing the ruling in the court of the US in 2012 and draws some implications from the perspective of business/industrial strategies. This paper has some limitations in that the lawsuit are still ongoing and it is the first attempt to find out the clue that connects legal and strategic issues in the rulings. Regardless of the limitations, however, this paper expects to contribute to raising the issues as to the importance of harmonizing the capabilities of managing technology with law, in order to survive under the era of creative economy.

• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.3
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• pp.227-235
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• 2016

This paper emphasized the necessity of the marine spatial planning (MSP) through the analysis of the major developmental projects which could make a contradiction based on the adequacy of the site selection and environmental impacts. The conflicting affairs between space utilization and management plan happen in the following ways: marine renewable energy development, sand mining, reclamation, construction of golf course in coastal area, thermal effluent and waste heat, erosion causing port development. The conflict of stakeholder continues caused by the accumulated environmental impact. For the reasons mentioned above, we found two things. First, it is necessary to comprehend the fact of developmental planning and MSP. Second, it is still unsatisfactory to connect the relevance of laws related to the spatial planning. For the reinforcement of marine environmental policy management, it is necessary to consolidate the property of site selection and assessment of developmental scale. Especially, while the strategic environmental assessment is in progress based on site selection and property of scale, consistent diagnosis is needed in the following concerns: the fact of the marine spatial planning, the relevance between national developmental plan and regional developmental plan, fisheries regulation, marine protected animals. For the environmentally sound and sustainable development (ESSD), MSP should have to be prepared based in a way of top-down including coastal and EEZ plan, relevance of ocean-use zoning and sector planning, 3-D spatial information. And also integrated information system have to be prepared through high-tech marine spatial information. In conclusion, consistent and relevant strategy for MSP should have to include the whole information related to the maritime affairs such as harbor, fishing port, fishing ground, coastal management, marine ecosystem generally.

• Journal of Korea Water Resources Association
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• v.46 no.12
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• pp.1193-1207
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• 2013

Increase of impervious area caused by overdevelopment has led to increase of runoff and then the problem of flooding and NPS were brought up. In addition, as decrease of base flow made groundwater level to decline, a stream that dries up is issued. low impact development (LID) method which is possible to mimic hydrological water cycle, minimize the effect of development, and improve water cycle structure is proposed as an alternative. As introduction of LID in domestic increases, the study on small watershed is in process mainly. Also, analysis of property of hydrological runoff and load on midsize watershed, like sewage treatment district, is required, the study on it is still insufficient. So, area applying LID practices from watershed of Dongrae stream is pinpointed and made the ratio and then expand it to watershed of Oncheon stream. Among low impact development practices, Green Roof, Porous Pavement, and Bio- retention are selected for the application considering domestic situations and simulated with SWMM-LID model of each watershed and improvement of water cycle and reduction of non-point pollution loads was analysed. Improvement of water cycle and reduction of non-point pollution loads were analyzed including the property of rainfall and soil over long term simulation. The model was executed according to scenario based on combination of LID as changing conductivity in accordance with soil type of the watershed. Also, this study evaluated area of LID application that meets the efficiency of conventional management as a criteria for area of LID practices applying to sewer treatment district by comparing the efficiency of LID application with that of conventional method.

• Journal of Environmental Impact Assessment
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• v.26 no.1
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• pp.11-26
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• 2017

Approximate empirical equations obtained by measuring overall noise levels at different distances have been used to evaluate environmental influence of the railway noise though the accurate prediction of noise levels is important. In this paper, a noise prediction model considering the frequency characteristics of noise sources and propagation was suggested to improve the accuracy of noise prediction. The railway noise source was assorted into track, wheel, traction and aerodynamic components and they were characterized with the source strength and speed coefficient at each octave-band frequency. Correction terms for the acoustic roughness and the track/bridge condition were introduced. The sound attenuation from a source to a receiver was calculated taking account of the geometrical divergence, atmospheric absorption, ground effect, diffraction at obstacles and directivity of source by applying ISO 9613-2. For obtaining the source strength and speed coefficients, the results of rolling noise model, numerical analysis and measurements of pass-by noise were analyzed. We compared the predicted and measured noise levels in various vehicles and tracks, and verified the accuracy of the present model. It is found that the present model gives less error than the conventional one, so that it can be applied to make the accurate prediction of railway noise effect and establish its countermeasures efficiently.