• Fashion & Textile Research Journal
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• v.20 no.3
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• pp.353-359
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• 2018

In this study, fused deposition modellig(FDM) 3D printing technology has been applied directly to polyester voil fabric to produce 3D printed lace/voil composite fabrics. A stereolithograpy(STL) file with a lace type 3D modelling under the various thickness were prepared and transformed into a g-code file using a g-code generator. The extrusion conditions for FDM 3D printing were controlled by 50mm/s of nozzle speed, $235^{\circ}C$ of nozzle temperature, $40^{\circ}C$ of heating bed temperature. 3D printed lace/voil composite fabriscs manufactured by 3D printing based on FDM using a thermoplactic polyurethane(TPU) filaments were obtained. To evaluate the mechanical properties and washability of the fabricated 3D printed lace/voil composite fabric, KES-FB system test, washing fastness test and dry cleaning resistance test were conducted. As 3D printing thickness increased, KOSHI, NUMERI, and FUKURAMI of 3D printed lace/voil composite fabric increased. From the results of the primary hand value test, 3D printed lace/voil composite fabrics were confirmed to be applicable to women's summer garments. As a result of the washability and dry cleaning resistance test of the 3D printed lace/voil composite fabrics, all samples were graded 4-5.

• Parasites, Hosts and Diseases
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• v.28 no.4
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• pp.241-252
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• 1990

In a basic attempt to develop the prophylactic and therapeutic measures on intestinal giantcystic disease of the Israel carp, C), prinks carpio nudum, the effects of physical and chemical factors on viability or survival of the spores of Thelchcnellus kiteuei were checked in vitro by means of extrusion test on the polar filament. When the fresh spores suspended with 0.45% and 0.9% scdium chloride solution and distilled water were laid at $5^{\circ}C$ and $28^{\circ}C$ for short terms, the extrusion rates increased until the 3rd day, meanwhile when son;e of them were suspended with Tyrode's solution at $-70^{\circ}C$ the rates increased gradually until the 8th day. Viabilities of the spores suspended with 0.9% saline and added antibiotics to the suspension at $5^{\circ}C$ for long terms lasted for 997 days and 1, 256 days (presumed values) at maximum, respectively. The spores suspended with distilled water at $28^{\circ}C$ for long terms survived 152.4 days, but the spores suspended with Tyrode's solution at $-70^{\circ}C$ for long terms showed almost the same viable pattern as early freezing stages up to 780 days. The spores suspended with Tyrode's solution, frozen at $-70^{\circ}C$ and thawed at $5^{\circ}C$, showed the highest rate of extrusion of the polar filament. In the case of frozen spores, the extrusion rates during heating tend to become higher in accordance with the increase of frozen period, and the critical points of 180 day-frozen spores to be killed were generally 78.5 hr. at $60^{\circ}C$, 23.4 hr. at $70^{\circ}C$, 189.1 min. at $80^{\circ}C$ or 10.5 min. at $90^{\circ}C$. The longer the spores were frozen, the more time was needed for the death of spores after thawing; 20 days-17.4 days, 100 days-33.2 days, and 400 days-37.8 days. The longer the spores were frozen, the more time was needed for the death of spores at a conventional when they were dried air drying condition, 540 days-23.5 days, 160 days-21.0 days, and 20 days-14.4 days. On the other hand, the longer the spores were frozen, the more spores were dead rapidly when they were irradiated with 10W UV-ray; 100 days-26.0 hr, 300 days-21.9 hr, and 540 days-13.9 hr. The time needed for killing 200 days-frozen spores by various disinfectants at 1, 000 ppd was 5.2 min. by calcium oxide, 10.4 min. by potassium permanganate, 27.8 min. by malachite green and 14.3 hr. by formalin. Transient inhibitory effects of the extrusion of the polar filament were observed by various antiprotozoal and antifungal agents in the descending order of ketoconazole. metronidasole and dapsone. The above results presume that full drying, followed by spraying CaO and maintaining sunny condition for a few days on the concrete bottoms of knish farm may be an effective method for the prevention of intestinal giant.cystic disease.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.35 no.4
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• pp.227-233
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• 2022

The 3D-printing technique is used for manufacturing objects by adding multiple layers, and it is relatively easy to manufacture objects with complex shapes. The 3D concrete printing technique, which incorporates 3D printing into the construction industry, does not use a formwork when placing concrete, and it requires less workload and labor, so economical construction is possible. However, 3D-printed concrete is expected to have a lower strength than that of molded concrete. In this study, the properties of 3D-printed concrete were analyzed. To fabricate the 3D-printed concrete samples, the extrusion path and shape of the samples were designed with Ultimaker Cura. Based on this, G-codes were generated to control the 3D printer. The optimal concrete mixing proportion was selected considering such factors as extrudability and buildability. Molded samples with the same dimensions were also fabricated for comparative analysis. The properties of each sample were measured through a three-point bending test and uniaxial compression test, and a comparative analysis was performed.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.24 no.6
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• pp.1293-1308
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• 2014

The cause of privacy extrusion in credit card company at 2014 is usage of the original data in test system. By Electronic banking supervision regulations of the Financial Supervisory Service and Information Security business best practices of Finance information technology (IT) sector, the data to identify the customer in the test system should be used to convert. Following this guidelines, Financial firms use converted customer identificaion data by loading in test system. However, there is some risks that may be introduced unintentionally by user mistake or lack of administrative or technical security in the process of testing. also control and risk management processes for those risks did not studied. These situations are conducive to increasing the compliance violation possibility of supervisory institution. So in this paper, we present and prove the process to eliminate the compliance violation possibility of supervisory institution by controlling and managing the unidentified conversion customer identification data and check the effectiveness of the process.

• Food Engineering Progress
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• v.15 no.4
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• pp.404-412
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• 2011

The purpose of this study is to prepare extruded rice flours suitable for baking rice cookies. The extruded rice flours were prepared at 100 and 130$^{\circ}C$ temperature and 25 and 27% moisture content in a co-rotating twin screw extruder. The rice extrudates were dried at 100$^{\circ}C$ for 18 hr and subsequently ground into the fine flour. Characteristics of the extruded rice flours were examined by rapid visco analysis, hydration property analysis, differential scanning calorimetry (DSC), and in vitro digestion test. Water absorption, solubility, and swelling power of all extruded rice flours were higher than those of native rice flour. DSC analysis showed that native rice flour had a peak at about 65$^{\circ}C$ while all extruded rice flours did not show any peaks since they were already gelatinized during the extrusion proess. Viscosity of the extruded rice flours decreased with increasing temperature and lowering moisture content in the extrusion proess. The extruded rice flours prepared at 130$^{\circ}C$ exhibited lower viscosity than those prepared at 100$^{\circ}C$. The operating temperature of the extrusion proess was critical for the starch digestion in vitro. The extruded rice flours prepared at 130$^{\circ}C$ showed a rapid decrease in digestible starch content while an increased level of slowly digestible starch content was observed compared to those treated at 100$^{\circ}C$ in the extruder. Cookies were prepared with a mixture of wheat flour and extruded rice flours at the ratio of 7 to 3. The cookies made with the extruded rice flours had lower spread factor and darker yellow color than those prepared with wheat flour only. Hardness of the extruded rice flour-added cookies was similar to that of the wheat flour cookie whereas their overall acceptance was better. Therefore the rice cookies partially supplemented with extruded rice flours may have a potential as early childhood foods which require soft texture and allergy reduction.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.55.2-55.2
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• 2012

Intensive theoretical and experimental studies have been carried out at Korean Institute of Science and Technology (KIST) on controlling the bio absorbing rate of the Mg alloys with high mechanical strength through tailoring of electrochemical potential. Key technology for retarding the corrosion of the Mg alloys is to equalize the corrosion potentials of the constituent phases in the alloys, which prevented the formation of Galvanic circuit between the constituent phases resulting in remarkable reduction of corrosion rate. By thermodynamic consideration, the possible phases of a given alloy system were identified and their work functions, which are related to their corrosion potentials, were calculated by the first principle calculation. The designed alloys, of which the constituent phases have similar work function, were fabricated by clean melting and extrusion system. The newly developed Mg alloys named as KISTUI-MG showed much lower corrosion rate as well as higher strength than previously developed Mg alloys. Biocompatibility and feasibility of the Mg alloys as orthopedic implant materials were evaluated by in vitro cell viability test, in vitro degradation test of mechanical strength during bio-corrosion, in vivo implantation and continuous observation of the implant during in vivo absorbing procedures. Moreover, the cells attached on the Mg alloys was observed using cryo-FIB (focused ion beam) system without the distortion of cell morphology and its organ through the removal of drying steps essential for the preparation of normal SEM/TEM samples. Our Mg alloys showed excellent biocompatibility satisfying the regulations required for biomedical application without evident hydrogen evolution when it implanted into the muscle, inter spine disk, as well as condyle bone of rat and well contact interface with bone tissue when it was implanted into rat condyle.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.1
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• pp.216-233
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• 2002

Due to the environmental problems of fuel consumption and vehicle emission, etc., automotive makers are trying to reduce the weight of vehicles. The most effective way to reduce a vehicle weight is to use lighter materials, such as aluminum and plastics. Aluminum Intensive Vehicle(AIV) has many advantages in the aspects of weight reduction, body stiffness and model change. So, most of automotive manufacturers are attempting to develop AIV using Aluminum Space Frame(ASF). The weight of AIV can be generally reduced to about 30% than that of conventional steel vehicle without the loss of impact energy absorbing capability. And the body stiffness of AIV is higher than that of conventional steel monocoque body. In this study, Aluminum Intensive Vehicle is developed and analyzed on the basis of steel monocoque body. The energy absorbing characteristics of aluminum extrusion components are investigated from the test and simulation results. The crush and crash characteristics of AIV based on the FMVSS 208 regulations are evaluated in comparison with steel monocoque. Using these results, the design concepts of the effective energy absorbing members and the design guide line to improve crashworthiness for AIV are suggested.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.3
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• pp.231-234
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• 2016

Pouch film is manufactured by laminating aluminum foil, polyamide film and polypropylene film with an adhesive or extrusion resin. However, a surface treatment is required for the aluminum because bonding does not occur easily between the aluminum foil and the polymer film. Thus, for this study, surface treatment experiments were performed in order to confirm the effect on adhesion strength. First, a variety of surface treatment solutions were coated on aluminum foil, and contact angle and surface morphology analysis was carried out for the surface-treated aluminum. For lamination of the surface-treated aluminum foil with polyamide film, a polyurethane base adhesive was prepared for the adhesive strength test specimens. The adhesive strength between the aluminum foil and the polyamide film of the resulting specimens was measured (UTM). With such an experiment, it was possible to evaluate the effect on adhesive strength of the various surface treatments.

• Computers and Concrete
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• v.20 no.3
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• pp.263-273
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• 2017

An experimental investigation is carried out on the failure mechanism of foam concrete with cold formed steel double C-Channels embedment. The foam concrete is made of cement and fly ash with a compressive strength between 9 and 24 MPa with different densities. Forty-eight tests have been carried out in four groups of specimens with various embedment depths of the steel in the concrete. Four modes of failure are observed, which include the independent failure of the C-Channels with and without a concrete block inside the channel as well as the combined failure of the two channels, and the failure of the extrusion block. A theoretical model has been developed to understand the failure process. The peak compressive force applied onto the C-Channels that causes failure is calculated. It is concluded that the failure involves independent slippage between two C-Channels, and the steel and the foam concrete blocks inside the C-Channels. A method to calculate the peak force is also developed based on the test results. The calculations also show that the shear strength of the foam concrete is about 8% of the compressive strength with ${\alpha}$ coefficient of 0.4 between the steel and concrete.

• Transactions of Materials Processing
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• v.22 no.2
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• pp.108-113
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• 2013

This paper demonstrates the lubricant performance in T-shape hot forging of Mg alloys. This processes induces complex plastic material flow of the initial billet such as simultaneous compression and extrusion deformations. Five lubricants with different amounts of graphite are applied to the T-shape forging at temperatures of 300 and $350^{\circ}C$. As the amount of graphite in the lubricant increases, the extruded depth gradually increases, which improves hot forgeability for Mg alloys. However, the lubricant performance decreases as forging temperature increases from 300 to $350^{\circ}C$. As the punch stroke increases, forgeability is considerably influenced by the lubricant. Thus, the selection of lubricants in hot forging of Mg alloys is critical when plastic deformation is severe.