• Preventive Nutrition and Food Science
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• v.11 no.4
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• pp.348-357
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• 2006

Nano is a unit that designates a billionth; accordingly nanotechnology could be described as the study and applications of the unique characteristics and phenomena of nanometer size materials. Applications of nanotechnology fall into two categories (one is top-down and the other is bottom-up). Currently, most products are the results of the top-down approach. Nanofoods have distinct functional characteristics stemming from the size, mass, chemical combinations, electrolytic features, magnetic properties of food sources at the nano level and which can be applied for safe absorption and delivery into the body. The greatest advantage of nanofood is that it permits the efficient use of small quantities of nutritional elements by increasing digestive absorption ability and by delivering natural elements without any change in their original characteristics. On the other hand, there are still unsolved problems, such as questions about safety and introduction of harmful material. The demand for new commercial food products is increasing, and commercial food producers are gradually combining nanotechnology and traditional food preparation methods. Nanofoods will improve our eating habits remarkably in the future. Tomorrow we will design nanofoods by shaping molecules and atoms. It will have a big impact on the food and food-processing industries. The future belongs to new products and new processes with the goals of customizing and personalizing consumer products. Nanotechnology is expected to be applied to not only foods themselves, but also to food packaging, production, safety, processing and storage. Also, it is believed that nanotechnology will be applied tracking finished products back to production facilities and even to specific processing equipment in those facilities. The aim of this study is the introduction of technology, applications, products, markets, R&D, and perspectives of nanofoods in the food industry.

• Ceramist
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• v.23 no.2
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• pp.211-230
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• 2020

Perovskite-type oxides with the nominal composition of ABO₃ can exsolve the B-site transition metal upon the controlled reduction. In this exsolution process, the transition metal emerges from the oxide lattice and migrates to the surface at which it forms catalytically active nanoparticles. The exsolved nanoparticles can recover back to the bulk lattice under oxidation treatment. This unique regeneration character by the redox treatment provides uniformly dispersed noble metal nanoparticles. Therefore, the conventional problem of traditional impregnated metal/support, i.e., sintering during reaction, can be effectively avoided by using the exsolution phenomenon. In this regard, the catalysts using the exsolution strategy have been well studied for a wide range of applications in energy conversion and storage devices such as solid oxide fuel cells and electrolysis cells (SOFCs and SOECs) because of its high thermal and chemical stability. On the other hand, although this exsolution strategy can also be applied to gas phase reaction catalysts, it has seldomly been reviewed. Here, we thus review recent applications of the exsolution catalysts to the gas phase reactions from the aspects of experimental measurements, where various functions of the exsolved particles were utilized. We also review non-perovskite type metal oxides that might have exolution phenomenon to provide more possibilities to develop higher efficient catalysts.

• Journal of Urban Science
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• v.11 no.2
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• pp.45-54
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• 2022

Recently, regulations on automobile exhaust gas emission are being strengthened. Accordingly, automobile exhaust gas emissions are expected to decrease and continue to decrease. On the other hand, many countries do not yet consider the emission of non-exhaust air pollutants from automobiles as important. Automobile non-exhaust substances are classified into three categories: tire dust emissions, brake wear emissions, and road scattering dust. In particular, in the case of tire dust, research results exist that pollutant emissions increase as the weight of a vehicle increases. Since the weight of trucks varies according to the load and the load along the axles is also different, it can be expected that the emission of PM10 from the tire dust will be different depending on the loading method. Therefore, this study was conducted on the amount of PM10 generated in tire dust considering the axle load of the truck according to the loading method. However, it was confirmed that the total amount of PM10 was less than that all loads are loaded in the front or rear when the load was evenly distributed in the front and rear of the cargo compartment. In particular, if the load is distributed evenly in the front and back of the cargo compartment and the load in the front part is divided into 2 to 6 and loaded, as the number of divided loading increases the amount of PM10 generated decreases. And when the load is divided into 6 pieces, the total amount of PM10 generated is 0.3952g, the minimum value. If the load is divided into 6 or more and loaded evenly, the total PM10 generated continuously increases and converges to about 0.3964g.

• Journal of the Korean housing association
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• v.25 no.6
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• pp.57-66
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• 2014

With regard to the pavilion buildings of Imcheonggak Gunjajeong and Donglakdang Gyejeong that are located within residential areas, this study focused on the construction background, the building owner's circumstances and the location environment of these buildings, and attempted to derive the architectural characteristics presented by these two pavilion buildings and, through this, to grasp the architect's intention of plan. The results of this study are as follows. With regard to Gunjajeong, it could be confirmed that, first, it is located in a propitious site and took the composition that follows the family ritual standards for the family rituals of the scholar-gentry class and opens to visitor access, and second, the floor height of the site and interior space was designed so that Munpilbong on the south and the Sarangchae on the west, and the Sadang on the east can be connected visually, and third, the authority and dignity of the head family were built through the symmetric 丁-shaped plane figure, the wide partition module, the form-centered building, and the hierarchical composition of the roof. On the other hand, with regard to Gyejeong, it could be confirmed that, first, it is located along the stream of Jagye valley that has no mountains in the front and in the back and took the composition that put the name symbolizing Taoist thoughts on the surrounding natural environment and was closed to visitor access but opens to nature, and second, with Jagye and Jagye surroundings as the main landscape, it built the concept of intended landscape that symbolizes the Taoist thoughts by giving names not only simply to the visible objects but also to surrounding rocks, and third, the asymmetric ㄱ-shaped plane composed a yard-centered space rather than emphasizing the shape, and connected the part of the plane with Jagye so as to be embodied as a personal inner self-perfecting place that closely communicates only with nature away from the mundane world.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.9
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• pp.928-939
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• 2012

This study evaluates wear comforts of water-vapor-permeable (WVP) garments through a measurement of various parameters such as skin and rectal temperatures, microclimate between skin and clothing, sweat rate, and subjective sensations (thermal, wet and comfort sensations) to correlate the physiological responses of the human body with its comfort feeling. Wear comfort during a specific exercise on a treadmill in a climatic chamber (temperature T = $20{\pm}0.5^{\circ}C$ and relative humidity H = $50{\pm}10%$) were studied using eight men wearing seven sportswear outfits (a long sleeve shirts and a long pants) made with seven different WVP fabrics. A comfort sensation was found to be highly correlated with skin T (p<.001), microclimate (T and H) between skin and clothing (p<.001) and sweat rate (p<.05). A regression model correlating comfort sensations and physiological responses obtained from wearer trials could be established: Y = 14.167 - 0.362 ${\times}$ X1 + 0.424 ${\times}$ X2 - 0.238 ${\times}$ X3 - 0.561 ${\times}$ X4 + 0.253 ${\times}$ X5 + 0.214 ${\times}$ X6 - 0.393 ${\times}$ X7 + 0.023 ${\times}$ X8 - 0.043 ${\times}$ X9. (Y = comfort sensation, X1 = forehead skin T, X2 = forearm skin T, X3 = hand skin T, X4 = thigh skin T, X5 = T of chest microclimate, X6 = T of thigh microclimate, X7 = chest sweat rate, X8 = H of back microclimate, X9 = H of thigh microclimate. The regression model obtained in this work can be used by manufacturers to objectively estimate the comfort sensation of sportswear before it is introduced to the consumer market. This study provides salient information to sportswear manufacturers and sportswear consumers.

• Fashion & Textile Research Journal
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• v.13 no.1
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• pp.32-43
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• 2011

This study investigate the transition about Japanese national costume kimono. The prototype of the present kimono is a kosode. The origin of kosode dates back to the mid-Heian period, when this type of kimono served as the everyday wear of commoners and an undergarment for court nobles, both men and women. In the Muromachi period, particularly after the Onin war, the kosode began to be by people of all classes. In the Muromachi period, kosode consisted mainly of woven textiles. In the Momoyama period, kosode became very elaborate, employing such various techniques as tie-dyeing, embroidery, metallic leaf(surihaku) and free-hand painting. These were further combined resulting in such techniques as tsujigahana dyeing and nuihaku, which are now considered to epitomize Momoyama-period textile design. A category of kosode of the early Edo period, known as Keicho kosode, is fashioned mainly from black, white, or red figured satin(rinzu), or from figured satin segmented in these three colors. Books of kosode designs began to be published in the Kambun era, when the merchant class was becoming economically powerful, kosode began to reflect its taste. During its final stage of development in the late 17th and early 18th centuries, yuzen dyeing achieved wide acceptance. From the late 18th century toward the early 19th century, kosode worn by the merchant class underwent drastic changes, while those worn by the samurai class changed little. In the after the late 18th century, clear differences in design and decorative methods appeared between the kosode worn by rich merchants and those worn by middle and lower class merchants.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.1
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• pp.36-46
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• 2013

This paper proposes the design of broadband spiral antenna for a potable non-linear junction detector (NLJD) system. To realize the broadband antenna design, it was considered optimization of the number of spiral turns by iteration calculation. Ground plane with the Archimedean spiral slit to keep the same current distribution between radiating plane and ground is considered for circular polarization design. In order to realize high directivity and high gain of the proposed antenna, the cavity wall and the metal cap which is located on back of ground plane were also considered in design. Measurement results of return loss were agreed well with VSWR 2:1 at interested frequency band among 2.4 to 2.44 GHz, 4.84 to 4.92 GHz and 7.28 to 7.36 GHz. Measured axial ratio was observed 3 dB below and showed reasonable agreement with simulation results. Characteristics of the RHCP(Right Hand Circular Polarization) with the measured gain of 6.8 dBi above at interested frequency band were also observed.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.605-610
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• 2004

Solid propellants allow thrusters to be light-weight, com-pact and robust because they require neither tank nor valve, Moreover, the solid propellant will not leak, spill or slosh. Consequently, the solid propellant thruster is one of the potential candidates for the microthruster. On the other hand, the control of the solid propellant combustion is difficult, since the conventional solid propellant continues to bum until all the stored propellant is consumed. Although particular devices like thrust reverser were designed to control the combustion, these devices were rarely used in the practical rocket motors. These devices rise thruster weight as well as complicate the thruster operation. In this study, a solid propellant microthruster using laser sustained combustion was designed in order to develop a high-efficiency microthruster overcoming the previously-mentioned difficulty. This designed thruster has semiconductor lasers and non-self-combustible solid propellants in addition to the conventional solid propellant thruster. In this designed thruster, the semiconductor laser controls the combustion of the non-self-combustible solid propellant. In order to demonstrate that the solid propellant combustion is controllable with laser, some non-self-combustible solid propellants were irradiated with the laser at a back-pressure of about 1㎪. A 40-W class Neodymium Yttrium Aluminum Garnet (ND:YAG) laser was used as a tentative alternate to the semiconductor laser. This experiment has shown that the solid propellant combustion was controllable with 10- W class laser irradiation.

• Journal of the Korea Convergence Society
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• v.11 no.3
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• pp.195-200
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• 2020

In this study, the flow analyses were performed on the fluid clutch turbine blade shapes of models 1, 2 and 3, with eight turbine blades tilted at 45 °, 40 °, and 35 ° angles on the propulsion shaft, respectively. The larger the angle of inclination on the propulsion shaft, the higher the flow pressure among the flow models after the back of the turbine blades. On the other hand, the smaller the angle of inclination on the propulsion shaft of the turbine wing, the lower the flow rate. It can be seen that the smaller inclination angle of the turbine blade surface on the propulsion shaft, i.e., the wing shape close to perpendicular to the flow of fluid, is more suitable for efficiently connecting and disconnecting the fluid clutch. By applying the flow analysis by type of turbine blade of fluid clutch,the study result at this paper is considered to be favorable as the convergent research material which can apply the aesthetic design.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.1
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• pp.26-38
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• 2020

A statistical test was carried out on the IID (Independently and Identically Distributed) assumption of the AM (Annual Maxima) data used to estimate the design wave height. The test was divided into independence (randomness) test and homogeneity test, and each test was conducted on AM data of 210 and 310 stations in coastal and inner coastal grids in typhoon and non-typhoon (monsoon) conditions. As a result of the independence test, the rejection ratios of the test are in the range of 1.8~5.3% and 1.4~6.0% for the non-typhoon and typhoon data sets, respectively. On the other hand, in the distribution difference test of typhoon data and nontyphoon data, the same distribution hypothesis was found to be rejected in the range of 47~79% according to the test method for both coastal grid and inner coastal grid. Therefore, in estimating design wave height by extreme value analysis, the estimation process by dividing the typhoon and non-typhoon data is appropriate.