• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.9
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• pp.1605-1614
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• 1992

The effects of % overload (% O.L), baseline stress intensity factor range (.DELTA. $K_{b}$) and dimension-less crack depth (a/W) are examined for the retardation behaviors after a single overload and high-low block loads in 7075-T73 aluminum alloy. And wheeler model, which is one of the fatigue life prediction models, is modified to predict retardation life using these test results. The retardation cycles( $N_{d}$) increased with a decrease in a/W and an increase in % O.L. and (.DELTA. $K_{b}$) These effects are more severe after high-low block loads than single overload. In the case of single overload, the main mechanisms of the retardation are the crack closure and the relaxation of K due to crack branching. But in the case of high-low block loads, that of the main mechanism is the crack closure caused by the accumulated compressive residual stree at the crack tip, which is related with the contact of fracture surfaces. Test results were multiple regression analyzed and got regressed shaping correction factors, (n)$_{REG}$, as function of %O.L., a/W and (.DELTA. $K_{b}$) Wheeler model is modified by using these (n)$_{REG}$. The number of delay cycles calculated by modified Wheeler model were in good agreement with the test results of this study.y.udy.y.y.y.

• The Journal of Korean Physical Therapy
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• v.30 no.5
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• pp.166-172
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• 2018

Purpose: This study compared the different sling and resistance exercises on pelvic rotation during active straight leg raises (ASLR) and on pain in patients with chronic low back pain (CLBP). Methods: Twenty subjects were divided randomly into a sling group (SG) and a resistance exercise group (REG). Internal oblique (IO), external oblique (EO), rectus abdominis (RA), and rectus femoris (RF) muscle activity; pelvic rotation angle during ASLR; and visual analogue scale, pressure pain threshold were measured. Sling and resistance exercises were then performed for 30 minutes and the measurements taken again. Results: Both groups showed significantly lower RF muscle activity and significantly higher EO and IO muscle activity (p<0.05). The RA muscle activity decreased significantly in the SG, but increased significantly in the REG (p<0.05). The pelvic rotation angle was significantly lower in the SG (p<0.05). The pain press threshold increased significantly in both groups (p<0.05). The visual analogue scale decreased significantly in the SG (p<0.05). Conclusion: Both exercises appear to be beneficial for modifying the muscle activity and pain control in the intervention of CLBP. On the other hand, the sling was more effective in increasing the pressure threshold than resistance exercise, and the pelvic rotation angle was reduced. Therefore, both exercises can help patients with CLBP change their muscle activity and control pain. CLBP patients should use a sling for short periods of time to learn to reduce the pain and control pelvic rotation.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.2
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• pp.468-473
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• 2007

The antidiabetic effect of Amomum xanthioides(A. xanthioides) extract was investigated. Alloxan caused the hyperglycemia and hypoinsulinemia by a selective destruction of pancreatic ${\beta}$-cell. Pretreatment of mouse with A. xanthiodies extract for 2 days prior to alloxan administration completely protected hyperglycemia induced by alloxan. In addition, administration of A. xanthioides extract to alloxan-induced diabetic mouse significantly abolished hyperglycemia, hypoinsulinemia, and, the reduction of size and number of insulin-secreting cells induced by alloxan. Administration of A. xanthioides extract to alloxan-induced diabetic mouse rapidly increased pancreatic Reg gene expression to 7 days, and then decreased. In alloxan-diabetic mouse. Reg gene expression was increased at 3 days after alloxan injection, and sustained until 24 days. The present results indicate that A. xanthioides extract contains potentially effective components exhibiting both protection and treatment of alloxan-induced diabetes. These results suggested that the antidiabetic effect of A. xanthoides extract may be mediated through the regeneration of pancreatic ${\beta}$-cells.

• Journal of Microbiology and Biotechnology
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• v.27 no.2
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• pp.306-315
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• 2017

Metabolic engineering with a high-yielding mutant, A. terreus AN37, was performed to enhance the production of itaconic acid (IA). Reportedly, the gene cluster for IA biosynthesis is composed of four genes: reg (regulator), mtt (mitochondrial transporter), cad (cis-aconitate decarboxylase), and mfs (membrane transporter). By overexpressing each gene of the IA gene cluster in A. terreus AN37 transformed by the restriction enzyme-mediated integration method, several transformants showing high productivity of IA were successfully obtained. One of the AN37/cad transformants could produce a very high amount of IA (75 g/l) in shake-flask cultivations, showing an average of 5% higher IA titer compared with the high-yielding control strain. Notably, in the case of the mfs transformants, a maximal increase of 18.3% in IA production was observed relative to the control strain under the identical fermentation conditions. Meanwhile, the overexpression of reg and mtt genes showed no significant improvements in IA production. In summary, the overexpressed cis-aconitate decarboxylase (CAD) and putative membrane transporter (MFS) appeared to have positive influences on the enhanced IA productivity of the respective transformant. The maximal increases of 13.6~18.3% in IA productivity of the transformed strains should be noted, since the parallel mother strain used in this study is indeed a very high-performance mutant that has been obtained through intensive rational screening programs in our laboratory.

• Journal of the Korean Applied Science and Technology
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• v.33 no.4
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• pp.751-761
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• 2016

In order to reduce the bitter taste of red ginseng extract(RGE), inclusion complexes(RGE-CD) of the extract with ${\alpha}$-, ${\beta}$-, ${\gamma}$-cyclodextine after acetic acid treatment at the steam process were prepared and studied for their taste by an electronic tongue. By complexation, the bitter taster- reducing efficacies of ${\alpha}$-CD and ${\beta}$-CD were much lower than that of ${\gamma}$-CD. This study suggested that by processing red ginseng with acetic acid it is possible to enhance the yield of both ginsenoside $Rg_3$ and nonpolar ginsenosides. Taste such as bitterness, sourness, saltiness, umami and sweetness of the red ginseng extract with different amounts of ${\alpha}$-CD, ${\beta}$-CD and ${\gamma}$-CD were checked using an electronic tongue. As a result, REG-${\gamma}$-CD10, prepared using 10%(w/w), showed significantly lower bitter taste than those of the other samples.

• Journal of the Korean Society of Physical Medicine
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• v.13 no.4
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• pp.113-121
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• 2018

PURPOSE: This study was conducted to identify a more effective intervention in sling and resistance exercise for chronic low back pain patients. METHODS: Seventy (70) subjects were randomly divided into the sling group (SG) and resistance exercise group (REG). Muscular activity of the internal oblique (IO), external oblique (EO), rectus abdominis (RA), and pelvic rotation angle during active straight leg raise (ASLR), a pressure pain threshold (PPT) and a visual analog scale (VAS) were measured. Sling and resistance exercises were conducted for 12 weeks. Intermediate measurements were taken after 8 weeks and final measurements were taken after 12 weeks. RESULTS: Both groups showed significantly decreased RA muscle activity and significantly increased IO muscle activity (p<.05). Additionally, EO muscle activity was significantly decreased in the REG, but significantly increased in the SG (p<.05), while the pelvic rotation angle and VAS were significantly decreased in the SG (p<.05). The pressure pain threshold was significantly increased in both groups (p<.05). CONCLUSION: Based on the results of this study, a 12-week intervention seems to be effective at improving back pain in both groups. However, a lower VAS was seen in the sling group after 8 weeks of intervention. Therefore, it is recommended that the sling be applied first when establishing a chronic back pain treatment program to shorten the treatment period and reduce the pain period.

• Journal of Digital Convergence
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• v.19 no.6
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• pp.113-132
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• 2021

This study is a new evaluation using the Arrhenius equation, which is known as the chemical reaction rate estimation equation, to evaluate the intrinsic and extrinsic value elements of patents as a model. The performance of the evaluation model was superior to the SVM, Logistic reg. and ANN models that were used as patent evaluation models in prior studies. In addition, there was a strong correlation between the predicted lifespan of the patent and the actual lifespan of the patent. These evaluation models may be used for evaluation purposes only, or if an evaluation is required, including a commercialization entity or technical characteristics.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.6
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• pp.313-330
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• 2021

In an autonomous driving system equipped with a camera and lidar, depth completion techniques enable dense depth estimation. In particular, using self-supervised learning it is possible to train the depth completion network even without ground truth. In actual autonomous driving, such depth completion should have very short latency as it is the input of other algorithms. So, rather than complicate the network structure to increase the accuracy like previous studies, this paper focuses on network latency. We design a U-Net type network with RegNet encoders optimized for GPU computation. Instead, this paper presents several techniques that can increase accuracy during the process of self-supervised learning. The proposed techniques increase the robustness to unreliable lidar inputs. Also, they improve the depth quality for edge and sky regions based on the semantic information extracted in advance. Our experiments confirm that our model is very lightweight (2.42 ms at 1280x480) but resistant to noise and has qualities close to the latest studies.

• Nuclear Engineering and Technology
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• v.53 no.7
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• pp.2387-2395
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• 2021

Seismic qualifications of electrical equipment, such as cabinet systems, have been emerging as the key area of nuclear power plants in Korea since the 2016 Gyeongju earthquake, including the high-frequency domain. In addition, electrical equipment was sensitive to the high-frequency ground motions during the past earthquake. Therefore, this paper presents the rocking behavior of the electrical cabinet system subjected to Reg. 1.60 and UHS. The high fidelity finite element (FE) model of the cabinet related to the shaking table test data was developed. In particular, the first two global modes of the cabinet from the experimental test were 16 Hz and 24 Hz, respectively. In addition, 30.05 Hz and 37.5 Hz were determined to be the first two local modes in the cabinet. The high fidelity FE model of the cabinet using the ABAQUS platform was extremely reconciled with shaking table tests. As a result, the dynamic properties of the cabinet were sensitive to electrical instruments, such as relays and switchboards, during the shaking table test. In addition, the amplification with respect to the vibration transfer function of the cabinet was observed on the third floor in the cabinet due to localized impact corresponding to the rocking phenomenon of the cabinet under Reg.1.60 and UHS. Overall, the rocking of the cabinet system can be caused by the low-frequency oscillations and higher peak horizontal acceleration.

• Advanced Industrial SCIence
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• v.1 no.2
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• pp.17-23
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• 2022

The purpose of this study is to analyze the health factors of the elderly according to the region by analyzing the physical fitness and fall efficacy of the female elderly living in rural and urban areas. The subjects of this study consisted of 98 female elderly people living in rural and urban areas who exercise health and cheerleading at least twice a week at the regional center(REG; n=46, 77.53±6.37 yrs, 151.81±5.26 cm, 60.00±9.42 kg, UEG; n=53, 73.57±2.70 yrs, 154.07±3.52 cm, 57.37±2.06 kg). Physical strength was measured for muscular endurance, cardiopulmonary endurance, and flexibility. Falling efficacy was measured using 10 items of Fall Efficacy Scale developed by Tinetti et al. Significant differences in flexibility and fall efficacy were found in urban older adults (p<.01, p<.05). There was no significant difference in muscular endurance and cardiac endurance (p>.05). In the future, studies to improve the imbalance of health factors of the elderly in the region should be continuously conducted.