• Fashion & Textile Research Journal
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• v.20 no.5
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• pp.569-582
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• 2018

The purpose of this study is to verify the impact protection performance and to evaluate the activity, design, fit, and pad characteristics of the fall impact protection clothing for elderly women. The protective clothing was designed as pants type and underwear type, and an impact protection pad in the form of a tightly connected regular hexagon piece was inserted in the hip and hip joints. The pad was made of two kinds of foam single pad and foam and gel combination pad so that they could be inserted into pants type and underwear type, respectively. The results of the shock absorption performance of the fall impact protective clothing showed that when the impact force of 4601N was applied to the pants type protective clothing, the impact force was reduced by 29% in the foam pad type and 26% in the gel and foam pad type. When the force of 5113N was applied to the underwear type, it decreased by 40% in the foam pad type and by 34% in the gel and foam pad type. As a result of wearing evaluation of subject group, it was found that fit and activity of underwear type was better than that of pants type. Foam pad type was evaluated to be lighter than gel and foam pad type in both the subject and the expert group and the gel and foam pad was evaluated to be more flexible in the expert group.

• Journal of Powder Materials
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• v.22 no.2
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• pp.93-99
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• 2015

This study investigated the microstructure and tensile properties of a recently made block-type Ni-Cr-Al powder porous material. The block-type powder porous material was made by stacking multiple layers of powder porous thin plates with post-processing such as additional compression and sintering. This study used block-type powder porous materials with two different cell sizes: one with an average cell size of $1,200{\mu}m$ (1200 foam) and the other with an average cell size of $3,000{\mu}m$ (3000 foam). The ${\gamma}$-Ni and ${\gamma}^{\prime}-Ni_3Al$ were identified as the main phases of both materials. However, in the case of the 1,200 foam, a ${\beta}$-NiAl phase was additionally observed. The relative density of each block-type powder porous material, with 1200 foam and 3000 foam, was measured to be 5.78% and 2.93%, respectively. Tensile tests were conducted with strain rates of $10^{-2}{\sim}10^{-4}sec^{-1}$. The test result showed that the tensile strength of the 1,200 foam was 6.0~7.1 MPa, and that of 3,000 foam was 3.0~3.3 MPa. The elongation of the 3,000 foam was higher (~9%) than that (~2%) of the 1,200 foam. This study also discussed the deformation behavior of block-type powder porous material through observations of the fracture surface, with the results above.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.426-430
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• 2001

Conventional smart foam is not applicable to active noise control in a duct having flow. Thus, this paper presents a ring-type smart foam as an alternative. The ring-type smart foam consists of polyurethane acoustic foam of lining shape and PVDF film embedded in the foam. The embedded PVDF element acts as an actuator to reduce noise at lower frequencies and the foam absorbs noise at higher frequencies. A feedforward adaptive filtered-x LMS controller is used to minimize the signal from the error microphone. Experiments are executed to reduce broadband and tonal noise.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.13 no.7
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• pp.499-507
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• 2003

This paper presents a method for active noise control (ANC) in a duct by using a ring-tyPe smart foam. The ring-type smart foam consists of an elastic porous material of lining shape and a PVDF film embedded In the material. The PVDF element acts as a secondary sound source to reduce the noise. Active noise control using a ring-type smart foam is only effective locally because of the way to excite radially. To enlarge the quiet zone, the duct Is lined with additional acoustic foam between the smart foam and the error microphone. When cancellation path ks optimized by the LMS/RLS algorithm, the computation power is reduced while control performance Is maintained. The filtered-x LMS algorithm is used to minimize the error signal.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11b
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• pp.1132-1137
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• 2001

The smart foam that is first proposed by Fuller(2) is not applicable to active noise control in a duct having flow. Thus. this paper presents the ring-type smart foam as an alternative. The ring-type smart foam consists of polyurethane acoustic foam of lining shape and PVDF film embedded along the mid-surface of the foam lining. A feedforward adaptive filtered-x LMS controller is used to minimize the signal from the error microphone. To enlarge quiet sound region. two error microphones are used to update system modeling filter (SIMO method). Sound intensity control using the ring-type smart foam is also discussed

• Proceedings of the KSME Conference
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• 2001.06b
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• pp.641-645
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• 2001

In this paper, it is discussed that active noise control in a circular duct using smart foam. Firstly, it is demonstrated that the potential of the conventional smart foam, proposed by Fuller, for active noise control in a duct. Conventional smart foam is not applicable to active noise control in a duct having flow. Thus, this paper presents a ring-type smart foam as an alternative. The ring-type smart foam consists of polyurethane acoustic foam of lining shape and PVDF film embedded in the foam. The embedded PVDF element acts as an actuator to reduce noise at lower frequencies and the foam absorbs noise at higher frequencies. A filtered-x LMS controller is used to minimize the signal from the error microphone. Experiments are executed to reduce broadband and tonal noise.

• Journal of the Korean Society of Radiology
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• v.17 no.6
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• pp.957-964
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• 2023

This study focused on hand sanitizer as a medium that can replace ultrasonic gel, which is vulnerable to contamination by bacteria that reside on the hand. Hand sanitizer produces a strong sterilization effect from germs resident on the hands through different sterilization principles depending on the ingredients. Select products of gel type, cream type, and foam type, except for liquid type with low viscosity, and ultrasonically apply one 62% ethanol gel type and one cream type, one benzalkonium chloride 0.066% cream type and one foam type, respectively. Using ATS-539 as a medium, image evaluation was performed on the axial and lateral resolution and penetration depth, and the presence or absence of an air layer between the probe and the phantom. As a result, in the evaluation of the axial and lateral resolution and the depth of penetration, all four experimental groups met the evaluation criteria. However, in the case of the foam type, although it was suitable for the evaluation criteria of resolution and penetration depth, dark shadows appeared on both sides except for the center of observation during image evaluation. Through this experiment, it was possible to confirm the possibility that the remaining three types of hand sanitizers except the foam type could replace the ultrasonic gel.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.29 no.1
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• pp.32-38
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• 2019

Carbon material was used for the new module-type bicycle accessory focusing on the user convenience through service design methodology. In the case of using the existing carbon material, the impact could not be endured while riding the bicycle and there was the case of breaking. To resolve this kind of problem, the new type of material (S Foam Core material) was applied. The intensity, twist intensity, shock absorbing power, and vibration were measured for the existing carbon material and the S Foam Core material. As a result, the S Foam Core material showed more outstanding results than the existing carbon material. This study produced prototype with the S Foam Core material to verify the performance through tests and report the result.

• Journal of KSNVE
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• v.11 no.3
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• pp.422-427
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• 2001

In this paper is presented passive-active noise control in a duct using a ring-type smart foam. The ring-type smart foam is comprised of a PVDF film embedded in elastic noise control foam of lining shape. The embeddedPVDF element acts as an actuator to reduce noise at lower frequencies and the foam absorbs noise at higher frequencies. By implementing an adaptive filtered-x LMS algorithm, experiments are performed to reduce both tonal and broadband noise in a duct with one end closed and the other end open.

• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.275-281
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• 2011

Solar reforming of methane with $CO_2$ was successfully tested with a direct irradiated absorber on a parabolic dish capable of $5kW_{th}$ solar power. The new type of catalytically activated metallic foam absorber was prepared, and its activity was tested. Ni was applied as the active metal on the gamma - alumina coated Ni metal foam for the preparation of the catalytically-activated metal foam layer. Compared to conventional direct irradiation of the catalytically-activated ceramic foam absorber, this new metallic foam absorber is found to exhibit a superior reaction performance at the relatively low insolation or at low temperatures. In addition, unlike direct irradiation of the catalytically-activated ceramic foam absorber, metallic foam absorber has better thermal resistance, which prevents the emergence of cracks caused by mechanical or thermal shock. The total solar power absorbed reached up to 2.1kW and the maximum $CH_4$ conversion was almost 40%.