• Structural Engineering and Mechanics
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• v.82 no.2
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• pp.259-270
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• 2022

The paper investigates the residual stresses arising in a thermoviscoelastic cylinder as a result of layer-by-layer deposition of material on its lateral surface. Internal stresses are caused by incompatible deformations that accumulate in the assembly as a result of joining parts with different temperatures. For the analysis of internal stresses, an analytical solution to the axisymmetric quasi-static problem of thermoelasticity for a growing cylinder is constructed. It is shown that the distribution of residual stresses depends on the scenario of the surfacing process. In this case, the supply of additional heat to the growing body can significantly reduce the unevenness of temperature fields and reduce the intensity of residual stresses. The most effective is uneven heating, which can be realized, by the action of an alternating current with a tunable excitation frequency. The temperature and residual stresses fields on the growing surface is analyzed numerically for Titanium and Copper materials.

• Journal of the Korean Ceramic Society
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• v.31 no.8
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• pp.902-910
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• 1994

Residual stress measurements were made for cylindrical glass rods to compare experimental results with the calculated values obtained by Instant Freezing Model. According to the photoelastic measurements, the stress ratio of surface compression and center tension was increased from 1.4 to 2.0 as the heat-treatment temperature was lowered, the fictitious forzen temperature was found to be closer to the heat-treatment temperature and the fictitious coefficient was increased.

• CELLMED
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• v.12 no.5
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• pp.1.1-1.3
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• 2022

Objective: A case report on the reduction of tinnitus and improvement in feeling of residual urine as a result of nutritional therapy Methods: A 46-year-old Korean man presented with tinnitus lasting for 10 days, and complained of discomfort with a feeling of residual urine for several years. Results: Tinnitus disappeared after one week of nutritional therapy, and the feeling of residual urine improved after 40 days. Conclusion: Nutritional therapy can be beneficial in the treatment of diseases for which a definitive diagnosis and treatment are lacking, such as tinnitus.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.68 no.1
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• pp.102-107
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• 2019

This paper proposes a method to improve the mass spectral detection performance of the residual gas analyzer. By improving the mode estimation method for setting the threshold value and improving the additive noise elimination method, it is possible to detect mass spectrums having low peak values of the threshold level difficult to distinguish from noise. Ion signal blocks for each mass index with noise removed by the improved method are effective for eliminating invalid ion signals based on the linear and quadratic fittings. The mass spectrum can be obtained from the quadratic fitted curves for the reconstructed ion signal block using only the valid ion signals. In addition, the resolution of the mass spectrum can be improved by correcting the error caused by the shift of the spectral peak position. To verify the performance of the proposed method, computer simulations were performed using real ion signals obtained from the residual gas analysis system under development. The simulation results show that the proposed method is valid.

• Steel and Composite Structures
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• v.17 no.2
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• pp.173-184
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• 2014

This study aimed to theoretical calculate the thermal residual stress in continuous SiC fiber reinforced titanium matrix composites. The analytical solution of residual stress field distribution was obtained by using coaxial cylinder model, and the numerical solution was obtained by using finite element model (FEM). Both of the above models were compared and the thermal residual stress was analyzed in the axial, hoop, radial direction. The results indicated that both the two models were feasible to theoretical calculate the thermal residual stress in continuous SiC fiber reinforced titanium matrix composites, because the deviations between the theoretical calculation results and the test results were less than 8%. In the titanium matrix composites, along with the increment of the SiC fiber volume fraction, the longitudinal property was improved, while the equivalent residual stress was not significantly changed, keeping the intensity around 600 MPa. There was a pronounced reduction of the radial residual stress in the titanium matrix composites when there was carbon coating on the surface of the SiC fiber, because carbon coating could effectively reduce the coefficient of thermal expansion mismatch between the fiber and the titanium matrix, meanwhile, the consumption of carbon coating could protect SiC fibers effectively, so as to ensure the high-performance of the composites. The support of design and optimization of composites was provided though theoretical calculation and analysis of residual stress.

• Food Science of Animal Resources
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• v.27 no.3
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• pp.299-307
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• 2007

Changes in nitrite content, TBARS content and color of meat products during storage were examined as part of studies addressing the reduction of residual nitrite and to ensure the safety of meat products. All 4 kinds of domestic meat product tested, Vienna sausage, bacon, smoked-ham and Dduggalbi, manufactured by C and L domestic companies had very low contents of residual nitrite, for below the legal tolerance limit of 70 ppm, and the residual nitrite decreased with storage. The reduction in nitrite content differed with each product, showing the greatest reduction in Vienna sausage and the least reduction in bacon when stored at $4^{\circ}C$. On the other hand, when stored at $-20^{\circ}C$, the nitrite content of bacon decreased more rapidly than the other meat products. The results of this study show that the nitrite content of meat products decreases during storage, and that the rate of decrease is quite dependent on the storage temperature. In addition, the nitrite contents of most domestic meat products are very low compared to the legal limits, thus the health risks of nitrite in meat products might not be of great concern. More research on the reduction of residual nitrite and on the development of alternatives to nitrite is necessary.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.741-745
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• 2002

Effect of gamma irradiation on inhibition of microbial growth and reduction of residual nitrite level in cooked pork sausage were studied during 4 weeks of storage at $4^{\circ}C$. Irradiation at 5 and 10 kGy significantly reduced the number of total aerobic bacteria and almost eliminated coliform bacteria. Irradiation reduced the content of residual nitrite in cooked pork sausage in a dose-dependent manner, and among packaging methods, the sausage with $CO_2$ (100%) packaging was the lowest level of residual nitrite. Results indicate that the irradiation combined with packaging is a useful technology to reduce the residual nitrite in cooked pork sausage.

• International Journal of Precision Engineering and Manufacturing
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• v.2 no.2
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• pp.17-25
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• 2001

In this paper, a theoretical study has been made to reduce the residual stress and birefringence in the injection-molded parts. An optimization program has been used to minimize the residual stresses and birefringence calculated from a simulation program. The thermally induced stress has been calculated using a linear viscoelasticity model. The flow stress and birefringence has been calculated using the Leonov's viscoelasticity model. This has been applied to the injection molding of a circular disc and a plate. the optimization has been done either by changing process variables while maintaining the mold temperature constant or by varying the mold-wall temperature with time. This study shows the significant reduction in residual stress and birefringence is possible through the optimization of processing conditions.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.7
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• pp.717-724
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• 2013

Industrial cranes are indispensable equipment in heavy industry. However, unwanted vibrations in cranes often cause accidents. Input shaping is widely accepted as a useful tool for removing residual vibration in cranes. A unity magnitude zero vibration (UMZV) input shaper is often used for cranes driven by on-off-type motors. However, although a UMZV input shaper minimizes residual vibration, the input shaper cannot prevent the crane from moving slightly further than expected from the original command. This paper describes an improved method of input shaping that can compensate for position inaccuracies, as well as remove the residual vibration of cranes. Experiments were performed to validate the proposed input-shaping method, illustrated through numerical simulations.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.11
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• pp.100-106
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• 2008

We have studied the characteristic changes of optical device using imprint lithography. An imprinted structure is inherently involved in residual stress due to the temperature and the pressure cycle during fabrication process. A structure with residual stress undergoes stress relaxation, which leads io dimensional change. Therefore, annealing processes was performed to reduce the residual stress of imprinted polymer channel. Reduction of residual stress was confirmed through dimensional change, birefringence, and the mechanical properties. We have fabricated an optical device, and it saw the optical intensity changes within 0.1% for 1 month.