• Journal of the Korea institute for structural maintenance and inspection
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• v.4 no.4
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• pp.149-160
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• 2000

As systematic methodologies are required for the evaluation on the durability of reinforced concrete structure, it is necessary to study and examine every factor which deteriorates the durability of structures. This paper aims to define factors affecting rebar corrosion and to establish a basis for a prediction of serviceability, regarding a state of harmful corrosion as a state when crack begins on the surface of concrete. The study results are followings; The corrosive current has changed by types of mixture, and this property enables the evaluations of corrosion resistance by mixture and concrete cover. The specimen using AE superplasticizer has better corrosion-resistance properties than non-AE specimen, as well those having low W/C and high unit cement weight. The procedure for calculation of durable year in this study is able to use as an indicator to establish mixture factors such as unit cement weight, W/C, amount of admixture, etc.

• Journal of Navigation and Port Research
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• v.28 no.8
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• pp.767-773
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• 2004

IMO(International Maritime Organization) is strongly proceeding with adoption of a new maritime environmental convention and coming into r1fed for regulation enhancement about the pollutants which are happened in a ship recently. Study about the conventions that our country currently comes into r1fect, and there is during forwarding and correspondence must be performed effectively. In this paper, International convention on the control of harmful Anti-Fouling system on ship, Ballast water management, Prevention of air pollution from ships, treat a main pending problem in ocean related environmental regulation convention.

• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.231-235
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• 2009

According to flow of energy, the loss occurs through walls, roofs, windows and so on. Among these case, most of the loss that is about 45% occurs through windows. windows's U-value is six times higher than wall's one according to Building code, so the loss through windows accounts for very much rates. Currently, Exterior wall's U-value about building envelope is 0.35~0.58W/ mK, but windows's one is 3.3W/ mK. It means that the loss through windows occupy very much amounts relatively. Therefore, the solution is required to reduce energy loss and increasing displeasure caused by excessive influx of solar energy through windows, to solve the problems Like decoloration on indoor furniture an clothes by harmful ultraviolet rays, air conditioning and increased cost. Therefore, on this paper, Thermal Performance was evaluated through actual test about high insulation Super Window which can improve thermal performance and the Simulation result was compared with actual resul by using Simulation program WINDOW and THERM.

• Journal of Electrical Engineering and Technology
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• v.13 no.5
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• pp.2107-2115
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• 2018

Over recent years, high-concentration of particulate matters (e.g., a.k.a. fine dust) in South Korea has increasingly evoked considerable concerns about public health. It is intractable to track and report $PM_{10}$ measurements to the public on a real-time basis. Even worse, such records merely amount to averaged particulate concentration at particular regions. Under this circumstance, people are prone to being at risk at rapidly dispersing air pollution. To address this challenge, we attempt to build a predictive model via deep learning to the concentration of particulates ($PM_{10}$). The proposed method learns a binary decision rule on the basis of video sequences to predict whether the level of particulates ($PM_{10}$) in real time is harmful (>$80{\mu}g/m^3$) or not. To our best knowledge, no vision-based $PM_{10}$ measurement method has been proposed in atmosphere research. In experimental studies, the proposed model is found to outperform other existing algorithms in virtue of convolutional deep learning networks. In this regard, we suppose this vision based-predictive model has lucrative potentials to handle with upcoming challenges related to particulate measurement.

• Journal of Sensor Science and Technology
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• v.29 no.6
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• pp.382-387
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• 2020

Hydrogen (H₂) is considered as a new clean energy resource for replacing petroleum because it produces only H₂O after the combustion process. However, owing to its explosive nature, it is extremely important to detect H₂ gas in the ambient atmosphere. This has triggered the development of H₂ gas sensors. 2-dimensional (2D) graphene has emerged as one of the most promising candidates for chemical sensors in various industries. In particular, graphene exhibits outstanding potential in chemoresistive gas sensors for the detection of diverse harmful gases and the control of indoor air quality. Graphene-based chemoresistive gas sensors have attracted tremendous attention owing to their promising properties such as room temperature operation, effective gas adsorption, and high flexibility and transparency. Pristine graphene exhibits good sensitivity to NO₂ gas at room temperature and relatively low sensitivity to H₂ gas. Thus, research to control the selectivity of graphene gas sensors and improve the sensitivity to H₂ gas has been performed. Noble metal decoration and metal oxide decoration on the surface of graphene are the most favored approaches for effectively controlling the selectivity of graphene gas sensors. Herein, we introduce several strategies that enhance the sensitivity of graphene gas sensors to H₂ gas.

• International Journal of Automotive Technology
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• v.4 no.3
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• pp.109-117
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• 2003

The analysis and evaluation of the transient performance by the transient response specifications under various acceleration speeds and types based on driver's typical acceleration habit are implemented by the experimental study to provide the appropriate direction for the transient control in a gasoline engine. The concept of the transient response specifications which consist of delay time, rising time, maximum overshoot and settling time, and the analysis method using them are introduced to evaluate the characteristics of the transient performance quantitatively. Furthermore four acceleration speeds and four acceleration types are set respectively to realize the various transient states which are similar to the real drive. Several performance parameters in terms of engine speed, manifold absolute pressure, fuel injection duration and air excess ratio are measured simultaneously during the various acceleration using a throttle actuator controlled by a PC. The transient response specifications characterized well the transient performance for the various acceleration speed and types quantitatively. Delay and rising time with increment of the acceleration speed became shorter, but settling time did longer. Intensified acceleration type appeared to be the most economical in view of fuel consumption, and linear acceleration type was found to have the least harmful emission concentration.

• Korean Institute of Interior Design Journal
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• v.15 no.3 s.56
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• pp.56-64
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• 2006

Human Being is being that have the reason as well as body, and first liaison consists through this body justly with outside. The essence of environmental problem such as today can speak that is a harmful traces for health that leave in air, water, soil that pass body. Actual nature is 'Ecological nature', that is necessary for human life directly in survival and offer the integrated relations with harmony. This grafting of principle, that is a construction for architecture and interior architecture in environment furtherance, is required. This is not a subject of usefulness and contemplation, but essential approach the cogredience, that is forming connection directly with nature, is required. Therefore, this research does Questel about 'Nature epistemology, which nature and human's relation can be integrated by alive practical relation. Through this, the Relatedness of 'Natural environment and construction surrounding' is accomplished 'the whole unity' and this research wish to investigate basis that a actual human work's environment can be completed as 'Ecological nature'.

• Design & Manufacturing
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• v.13 no.3
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• pp.41-47
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• 2019

In conventional machining, the use of cutting fluid is essential to reduce cutting heat and to improve machining quality. However, to increase the performance of cutting fluids, various chemical components have been added. However, these chemical components during machining have a negative impact on the health of workers and cutting environment. In current machining, environment-friendly machining is conducted using MQL (minimum quantity lubrication) or cryogenic air spraying to minimize the harmful effects. In this study, the injection nozzle that can combined injecting minimum quantity lubrication(MQL) and cryogenic gas was designed and the shape optimization was performed by using computational fluid dynamics(CFD) and design of experiment(DOE). Performance verification was performed for the designed nozzle. The diameter of the sprayed fluid at a distance of 30 mm from the nozzle was analyzed to be 21 mm. It was also analyzed to lower the aerosol temperature to about 260~270K.

• Journal of the Korean Institute of Educational Facilities
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• v.26 no.3
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• pp.3-13
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• 2019

Purpose: The human body is a chemical laboratory. Artists are exposed to a variety of chemicals in art studio space and the art materials used in the creation contain toxic ingredients, exposing them to a variety of incurable diseases, including cancer. It aims to analyze the problems of the studio space environment and the risks of art materials, which are fundamental causes of the outbreak of incurable diseases, and to derive the direction of specific practices that can reduce the occurrence of incurable diseases by artists. Method: The harmfulness of an artist's creative space is the cause of a disease outbreak, and two primary factors cause it. One is the environmental hazards caused by the use of tools, air pollution, and chemical hazards caused by art materials in the architectural space environment of the studio. Necessary measures are put forward to control disease outbreaks by identifying the status and cause of intractable diseases caused by studies. Result: The plan is urgent for the establishment of safety rules and regular pre-trainthese two factors and analyzing the results of prior research and implementation investigationing, the legal provisions of studio architecture design and the introduction of labelling rules to control the distribution of harmful art materials.

• Korean Journal of Materials Research
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• v.28 no.12
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• pp.685-690
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• 2018

In this study, a multifunctional ophthalmic lens material with an electromagnetic shielding effect, high oxygen permeability, and high water content is tested, and its applicability is evaluated. Metal oxide nanoparticles are applied to the ophthalmic lens material for vision correction to shield harmful electromagnetic waves; the pyridine group is used to improve the antibacterial effect; and silicone substituted with urethane and acrylate is employed to increase the oxygen permeability and water content. In addition, multifunctional tinted ophthalmic lens materials are studied using lens materials with an excellent antibacterial effect (2,6-difluoropyridine, 2-fluoro-4-pyridinecarboxylic acid) and functional (UV protection, high wettability) lens materials (2,4-dihydroxy benzophenone, 2-hydroxy-4-(methacryloyloxy)benzophenone). To solve problems such as air bubbles generated during the polymerization process for the manufacturing and turbidity of the lens surface, polymerization conditions in which the defect rate is minimized are determined. The results show that the polymerization temperature and time are most appropriate when they are $110^{\circ}C$ and 40 minutes, respectively. The optimum injection amount of the polymerization solution is 350 ms. The turbid phenomenon that appears in lens processing is improved by 10 to 95 % according to the test time and conditions.