• Journal of the Korean Society of Clothing and Textiles
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• v.41 no.3
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• pp.458-467
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• 2017

There is increased interest in clothes dryers and garments made of spandex-blend woven fabrics; however, there is limited information available for the laundering and drying these clothes. This study investigates the effects of washing and drying on shrinkage, skewness, and wrinkle for woven fabrics with and without spandex. When spandex with good elastic recovery was blended, the deformed shape from washing and drying improved skewness and wrinkle by easily returning to its original shape. However, these properties had a negative effect on shrinkage in terms of length and area change. When the influence of clothes maintenance was classified, the drying process had the biggest influence of 58%, followed by spinning-rinsingwashing. Tumble drying, in which the fabric is exposed to mechanical force and heat for a long period, had more negative effects on the dimensional stability than line drying. The spandex blend had the effect of preventing skewness and wrinkle in garments, but it was also shown to accelerate shrinkage by garment maintenance cycles. It was important to control drying in order to reduce shrinkage during the maintenance process; consequently, this had the greatest influence on the dimensional stability of fabrics. Therefore, line drying was more advantageous for spandex-blend fabrics than tumble drying in terms of management for shrinkage, skewness, and wrinkle.

• Journal of the Society of Naval Architects of Korea
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• v.41 no.3
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• pp.60-71
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• 2004

Nowadays, We have had a growing interest in high-speed vessels' because it is very important to save time and cost in marine transportation. The development of hull form for high-speed vessels is high priority to secure the competitive power for the transportation of cargos. Therefore, the demand of the high-speed vessels is gradually increased, but the conventional hull forms are limited by rapidly increasing resistance upon the increase of ship speed in high-speed region. Therefore, new concepts for the hull form of high-speed vessels have been requested. One of the derived hull forms for that demand is the hull form of trimaran type. Trimaran has a very slender main hull as compared with conventional single hull so that is reduced in wave resistance. The slender main hull has the undesirable characteristics of stability, but two side hulls make up for the week points in the stability. That is, trimaran is able to have desirable performances for the resistance and stability. In this paper, for the design of 200TEU class container vessel with trimaran type, which will be cruised in Yellow-Sea region, firstly a preliminary hull is designed, and the model test is carried out with the variation of side hull position. From the experience of the preliminary hull form design, an improved hull form for the 200TEU container are designed, and the model tests are carried out. Also, a numerical computation technique is adopted for the simulation of flow phenomena around the designed hull forms. The final hull form is compared with existing ships for the resistance performance from the computation with computer and ship model tests.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.150-157
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• 2019

The purpose of this study was investigate the effect of gastrocnemius(GCM) muscle length on the dynamic balance and antero-posterior pressure distribution of foot. Thirty subjects were recruited and each subject was classified with control experimental and control group according to GCM muscle length. The experimental group included subjects with shortness of GCM muscle length, the control group included subjects with normal length of GCM. The dynamic balance and antero-posterior pressure distribution of foot were measured by Biorescue equipment. To evaluate dynamic balance, we collected data of limit of stability in antero-posterior direction. We analyzed the data by using independent t-test. The alpha level was set 0.05. The results showed that the dynamic balance and antero-posterior pressure distribution of foot were significantly different between two groups (p<0.05). This study suggests that the shortness of GCM affects anterior limited of stability in dynamic balance and anterior pressure distribution of foot. Therefore, it is important to maintain optimal GCM muscle length for normal balance ability and prevention of musculoskeletal disease.

• Journal of Environmental Science International
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• v.22 no.11
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• pp.1509-1517
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• 2013

So far, most studies associated with soil carbon sequestration have been focused on long term aspect. However, information regarding soil carbon sequestration in short term aspect is limited. This study was conducted to determine changes of soil organic carbon content and stability of carbon in response to compost application rate and tillage management during rice growing season(150 days) in short term aspect. Under pot experiment condition, compost was mixed with an arable soil at rates corresponding to 0, 6, 12, and 24 Mg/ha. To determine effect of tillage on soil carbon sequestration, till and no-till treatments were set up in soils amended with application rate of 12 Mg/ha. Compost application and tillage management did not significantly affect soil organic carbon(SOC) content in soil at harvest time. Bulk density of soil was not changed significantly with compost application and tillage management. These might result from short duration of experiment. While hot water extractable organic carbon(HWEOC) content decreased with compost application, humic substances(HS) increased. Below ground biomass of rice increased with application of compost and till operation. From the above results, continuos application of compost and reduce tillage might improve increase in soil organic carbon content and stability of carbon in long term aspect.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.7
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• pp.903-907
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• 2006

Frozen stability of proteins recovered from white croaker and jack mackerel have been tested by measuring oxidation of residual lipid, browning, total plate count, and texture of gel during storage at $-20^{\circ}C$. The oxidation of residual lipid in recovered protein from Jack mackerel increased up to 60 days, and then decreased. Both browning values significantly was increased after 90 days. Total plate count was $1.2{\times}10^4\;CPU/g$ for proteins recovered from white croaker and $3.2{\times}10^4\;CPU/g$ for proteins recovered from jack mackerel in 60 days. The breaking force, deformation, and whiteness of gel formed from proteins recovered from white croaker did not change up th 120 days significantly, while proteins recovered from jack mackerel did not form heat-induced gel in 120 day. Frozen storage of the recovered protein was limited to 90 days for white croaker and to 60 days for jack mackerel considering the gelling ability and textural properties.

• Journal of Korean Physical Therapy Science
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• v.28 no.1
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• pp.11-22
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• 2021

Background: This study was to investigate the effects of active stretching and stability exercise on piriformis muscle thickness and low back pain of male patients with chronic low back pain. Design: Randomized Controlled Trial. Methods: 45 male patients participated in this study. All subjects were randomly assigned. Subjects divided into 15 who underwent contract relaxation (CR) of the proprioceptive neuromuscular facilitation (PNF) to their hip joints, 15 who underwent a combination of isotonic (CI) of the PNF, and the rest 15 who underwent the two techniques (CR+CI). Real-time diagnostic ultrasound was used to measure thickness of the piriformis muscles. The visual analogue scale (VAS) was used to measure degrees of low back pain. A two-way repeated measures ANOVA was used to compare the average values. The SPSS 24.0 was used as the statistical program, and the significance level was set at .05. Results: The CR and the CR+CI groups had more decreased thickness of piriformis muscle when compared to the CI group. The CR+CI group had more decreased pain when compared to the CR and the CI groups. Conclusion: These results suggest that combination of stretching and stability exercise was effective on male patients with chronic low back pain showing limited hip medial rotation.

• Journal of Veterinary Science
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• v.25 no.1
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• pp.2.1-2.14
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• 2024

Background: Sufficient surgical resection is necessary for effective tumor control, but is usually limited for vertebral tumors, especially in the cervical spine in small animal neurosurgery. Objective: To evaluate the primary stability and safety of customized three-dimensional (3D)-printed implants for cervical spine reconstruction after total vertebrectomy. Methods: Customized guides and implants were designed based on computed tomography (CT) imaging of five beagle cadavers and were 3D-printed. They were used to reconstruct C5 after total vertebrectomy. Postoperative CT images were obtained to evaluate the safety and accuracy of screw positioning. After harvesting 10 vertebral specimens (C3-C7) from intact (group A) and implanted spines (group B), implant stability was analyzed using a 4-point bending test comparing with groups A and C (reconstituted with plate and pins/polymethylmethacrylate after testing in Group A). Results: All customized implants were applied without gross neurovascular damage. In addition, 90% of the screws were in a safe area, with 7.5% in grade 1 (< 1.3 mm) and 2.5% in grade 2 (> 1.3 mm). The mean entry point and angular deviations were 0.81 ± 0.43 mm and 6.50 ± 5.11°, respectively. Groups B and C significantly decreased the range of motion (ROM) in C3-C7 compared with intact spines (p = 0.033, and 0.018). Both groups reduced overall ROM and neutral zone in C4-C6, but only group B showed significance (p = 0.005, and 0.027). Conclusion: Customized 3D-printed implants could safely and accurately replace a cervical vertebra in dog cadavers while providing primary stability.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.26 no.1
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• pp.35-40
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• 2016

End milling process is one of the broadly used manufacturing process for precision machined parts and products. Machining performance is often limited by chatter vibration at the tool-workpiece interface. Chatter vibration is a type of machining self-excited vibration which originated from the variation in cutting forces and the flexibility of the machine tool structure. Even though lots of cutting tooling methods are developed and used in machining process, precise analysis of cutting tooling effect in view of chatter vibration behavior. This study presents numerical and experimental approaches to verify and effects of various cutting parameters to affect to chatter vibration stability. Acquired knowledge from this study will apply the optimal cutting conditions to improve a machining process.

• International Journal of High-Rise Buildings
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• v.6 no.3
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• pp.249-259
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• 2017

The use of high-strength steels in construction of highrise and mega building structures can bring about many technological advantages from fabrication to erection. However, key design criteria such as local and lateral stability in current steel design specifications were developed based on tests of ordinary steels which have stress-strain characteristics very different from that of high strength steels. A series of tests on 800 MPa tensile strength steel (HSA800) members are summarized in this paper which were conducted to investigate the appropriateness of extrapolating current ordinary-steel based design criteria to high strength steels. 800 MPa I-shape beam specimens designed according to flange local buckling (FLB) criteria of the AISC Specification developed a sufficient strength for elastic design and a marginal rotation capacity for plastic design. It is shown that, without introducing distinct and significant yield plateau to the stress-strain property of high-strength steel, it is inherently difficult to achieve a high rotation capacity even if all the current stability limits are met. 800 MPa I-shape beam specimens with both low and high warping rigidity exhibited sufficient lateral torsional buckling (LTB) strength. HSA800 short-column specimens with various edge restraint exhibited sufficient local buckling strength under uniform compression and generally outperformed ordinary steel specimens. The experimental P-M strength was much higher than the AISC nominal P-M strength. The measured residual stresses indicated that the impact of residual stress on inelastic buckling of high-strength steel is less. Cyclic seismic test results showed that HSA800 members have the potential to be used as non-ductile members or members with limited ductility demand in seismic load resisting systems. Finally, recent applications of 800 MPa high strength steel to highrise and mega building structures in Korea are briefly presented.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3888-3893
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• 2014

The number of waste tires is increasing. One effective recycling method is the pyrolysis of waste tires. Using the pyrolyzed carbon black from waste tires, the characteristics of permanent deformation for PA-13mm porous mixture were evaluated. The confining pressure of 138 kPa and deviatoric stress of 551 kPa were adopted. The testing temperature was $45^{\circ}$ and 50 gyrations of the gyratory compactor was used to simulate the medium traffic level. The mixture modified by 10% PCB showed the largest Marshall Stability of 3.41 kN. The stability of the mixtures with PCB was 50% higher than that of mixture without PCB. The limited laboratory test showed that the use of PCB in a porous pavement decreases the permanent deformation and will be an effective alternative method to reducing the permanent deformation of a porous pavement.