• Korean Journal of Social Welfare Studies
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• v.44 no.2
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• pp.359-385
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• 2013

The study looked into the effect of internet utilization (utilization frequency and utilization ability in internet) on the life satisfaction level for the elderly in depth. In order to verify the correlation of two variables, a mediating model structured by ego integrity was used which gave out the Seoul welfare panel data created by Seoul welfare foundation in 2010. The total sample size was a group of 1862 elders aged over 60. When it came to our research methods, structured equation analysis was applied to verify the mediating effect and theoretical background. The findings are as follows: First, elderly's utilization frequency in internet is not an influencing factor to life satisfaction and elderly's utilization ability in internet is an influencing factor to life satisfaction. Second, the level of social activity did function as partial mediator on relationship between elderly's utilization ability in internet and life satisfaction. This study indicates theoretical and practical interventions to promote elderly's utilization in internet.

• Journal of Powder Materials
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• v.30 no.5
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• pp.431-435
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• 2023

An irradiation hardening of Inconel 718 produced by selective laser melting (SLM) was studied based on the microstructural observation and mechanical behavior. Ion irradiation for emulating neutron irradiation has been proposed owing to advantages such as low radiation emission and short experimental periods. To prevent softening caused by the dissolution of γ' and γ" precipitates due to irradiation, only solution annealing (SA) was performed. SLM SA Inconel 718 specimen was ion irradiated to demonstrate the difference in microstructure and mechanical properties between the irradiated and non-irradiated specimens. After exposing specimens to Fe³⁺ ions irradiation up to 100 dpa (displacement per atom) at an ambient temperature, the hardness of irradiated specimens was measured by nano-indentation as a function of depth. The depth distribution profile of Fe³⁺ and dpa were calculated by the Monte Carlo SRIM (Stopping and Range of Ions in Matter)-2013 code under the assumption of the displacement threshold energy of 40 eV. A transmission electron microscope was utilized to observe the formation of irradiation defects such as dislocation loops. This study reveals that the Frank partial dislocation loops induce irradiation hardening of SLM SA Inconel 718 specimens.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.18 no.4
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• pp.998-1019
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• 2024

Mobile cloud computing is a very attractive service paradigm that outsources users' data computing and storage from mobile devices to cloud data centers. To protect data privacy, users often encrypt their data to ensure data sharing securely before data outsourcing. However, the bilinear and power operations involved in the encryption and decryption computation make it impossible for mobile devices with weak computational power and network transmission capability to correctly obtain decryption results. To this end, this paper proposes an outsourcing decryption algorithm of verifiable transformed ciphertext. First, the algorithm uses the key blinding technique to divide the user's private key into two parts, i.e., the authorization key and the decryption secret key. Then, the cloud data center performs the outsourcing decryption operation of the encrypted data to achieve partial decryption of the encrypted data after obtaining the authorization key and the user's outsourced decryption request. The verifiable random function is used to prevent the semi-trusted cloud data center from not performing the outsourcing decryption operation as required so that the verifiability of the outsourcing decryption is satisfied. Finally, the algorithm uses the authorization period to control the final decryption of the authorized user. Theoretical and experimental analyses show that the proposed algorithm reduces the computational overhead of ciphertext decryption while ensuring the verifiability of outsourcing decryption.

• Korean Journal of Materials Research
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• v.34 no.6
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• pp.267-274
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• 2024

In this study, four different samples of Se₆₀Ge_40-xBi_x chalcogenides glasses were synthesized by heating the melt for 18 h in vacuum Pyrex ampoules (under a 10^-4 Torre vacuum), each with a different concentration (x = 0, 10, 15, and 20) of high purity starting materials. The results of direct current (DC) electrical conductivity measurements against a 1,000/T plot for all chalcogenide samples revealed two linear areas at medium and high temperatures, each with a different slope and with different activation energies (E₁ and E₂). In other words, these samples contain two electrical conduction mechanisms: a localized conduction at middle temperatures and extended conduction at high temperatures. The results showed the local and extended state parameters changed due to the effective partial substitution of germanium by bismuth. The density of extended states N(E_ext) and localized states N(E_loc) as a function of bismuth concentration was used to gauge this effect. While the density of the localized states decreased from 1.6 × 10¹⁴ to 4.2 × 10¹² (ev^-1 cm^-3) as the bismuth concentration increased from 0 to 15, the density of the extended states generally increased from 3.552 × 10²¹ to 5.86 × 10²¹ (ev^-1 cm^-3), indicating a reduction in the mullet's randomness. This makes these alloys more widely useful in electronic applications due to the decrease in the cost of manufacturing.

• Archives of Plastic Surgery
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• v.50 no.6
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• pp.586-592
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• 2023

Background One-stage reconstruction with "thin perforator flaps" has been attempted to salvage limbs and restore function. The deep inferior epigastric perforator (DIEP) flap is a commonly utilized flap in breast reconstruction (BR). The purpose of this study is to present the versatility of DIEP flaps for the reconstruction of large defects of the extremities. Methods Patients with large tissue defects on extremities who were treated with thin DIEP flaps from January 2016 to January 2018 were included. They were minimally followed up for 36 months. We analyzed the etiology and location of the soft tissue defect, flap design, anastomosis type, outcome, and complications. We also considered the technical differences in the DIEP flap between breast and extremity reconstruction. Results Overall, six free DIEP flaps were included in the study. The flap size ranged from 15 × 12 to 30 × 16 cm². All flaps were transversely designed similar to a traditional BR design. Three flaps were elevated with two perforators. Primary closure of the donor site was possible in all cases. Five flaps survived with no complications. However, partial necrosis occurred in one flap. Conclusion A DIEP flap is not the first choice for soft tissue defects, but it should be considered for one-stage reconstruction of large defects when the circulation zone of the DIEP flap is considered. In addition, this flap has many advantages over other flaps such as provision of the largest skin paddle, low donor site morbidity with a concealed scar, versatile supercharging technique, and a long pedicle.

• Journal of the Korean Society of Industry Convergence
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• v.27 no.4_2
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• pp.833-840
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• 2024

According to recent data from the Korea Meteorological Administration(KMA), the frequency of typhoons around the Korea Peninsula is almost unchanged, but the intensity is on the rise due to climate change. A typhoon that has become so powerful can cause partial or complete damage to the traffic signal structures, limiting the operation of the vehicle and causing traffic congestion. If the traffic signal structure fails to function properly due to the influence of the typhoon, not only the v ehicle operation will be disrupted, but also direct damage to the traffic signal structure will occur. In addition, if the social overhead cost of traffic congestion is included, the recovery cost caused by the typhoon will increase to an extent that it is difficult to estimate. Therefore, in this study, a wind tunnel experiment was performed by producing a wind tunnel model of an existing fixed traffic signal structure and a traffic signal structure in which signs and traffic lights are hinged. Also, The fixed and hinge structures were modeled as 3D finite elements, and wind-resistant analysis was performed by wind speed, and, wind-resistant safety of traffic signal structures were analyzed and examined through wind-resistant analyses. From the comparative analysis of the results of experiment and FE analysis, it was known that the stress reduction rate of the hinge connection structure was at least 30% compared to that of the fixed connection structure from the results of the wind tunnel experiment and FE analysis. And As a result of finite element analysis for the maximum design wind speed of 50m/s, it was found that the maximum stress generated in the existing structure exceeded all the yield stress, but the maximum stress of the hinge connection structure was within the yield stress. Finally The hinge connection structure showed a relatively large stress reduction rate as the wind speed increased and the length of the lateral beam was shorter at the same wind speed.

• Biomolecules & Therapeutics
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• v.32 no.5
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• pp.601-610
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• 2024

Tofacitinib, a Janus kinase (JAK) inhibitor used to treat rheumatoid arthritis, is metabolized through hepatic cytochrome P450 (CYP), specifically CYP3A1/2 and CYP2C11. Prolonged administration of rheumatoid arthritis medications is generally associated with an increased risk of renal toxicity. Loganin (LGN), an iridoid glycoside, has hepatorenal regenerative properties. This study investigates the potential of LGN to mitigate acute kidney injury (AKI) and its effects on the pharmacokinetics of tofacitinib in rats with cisplatin-induced AKI. Both intravenous and oral administration of tofacitinib to AKI rats significantly increased the area under the plasma concentration-time curve from time 0 to infinity (AUC) compared with control (CON) rats, an increase attributed to the decelerated non-renal clearance (CL_NR) and renal clearance (CL_R) of tofacitinib. Administration of LGN to AKI rats, however, protected kidneys from severe impairment, restoring the pharmacokinetic parameters (AUC, CL_NR, and CL_R) of tofacitinib to those observed in untreated CON rats, with partial recovery of kidney function, as evidenced by an increase in creatinine clearance. Possible interactions between drugs and natural components should be considered, especially when co-administering both a drug and a natural extract containing LGN or iridoid glycosides to patients with kidney injury.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.6
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• pp.395-401
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• 2002

The combination of early heading time, maturing time and short grain-filling period is very important to develop early varieties in winter barley. The 4 parental half diallel crosses (parents, $F_1$s, $F_2$s) were cultivated at the field. The heading date was from April 3 to 26, maturing date from May 15 to 27 and grain-filling period from 31 days to 42 days, showing that the varietal differences about the 3 traits were remarkable. According to half diallel cross analyses, Dongbori 1 for heading time (late heading) was dominant, but Oweolbori (early heading) was recessive, showing partial dominance with high additive component of genetic variance. Dongbori 1 for maturing time was dominant, but Oweolbori was recessive, showing partial dominance with high additive variance. Reno for grain-filling period (short grain-filling period) was dominant, but Oweolbori (long grain-filling period) was recessive with additive, and partial dominance. There were highly significant mean squares for both GCA and SCA effects on the heading and maturing times, and GCA/SCA ratios for all traits were high, showing the additive gene effects more important. Sacheon 6 and Oweolbori had greater GCA effects for early heading and maturing times, and Dongbori 1 and Reno had greater GCA effects for late times. GCA effects were highly significant in $F_1$ and $F_2$ generations, showing high GCA/SCA ratios (7.02). The heading and maturing times in field were positively correlated with antifreeze proteins concentrations, accumulation, resistance to photoinhibition and winter survival, respectively) but the grain-filling period did negatively correlated with the trails.

• Journal of the Korean Arthroscopy Society
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• v.9 no.2
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• pp.174-179
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• 2005

Purpose: To study the long-term outcome of arthroscopic meniscectomy with regard to clinical symptoms and radiographic signs of osteoarthritic change. Materials and Methods: The materials for the investigation consisted of 79 individuals among 144 patients who underwent knee arthroscopy due to an isolated meniscal tear from October 1990 to September 1992 in our hospital. Those 79 individuals were followed up for $10{\sim}15$ years after the knee arthroscopy and were took clinical examination through the review of knee radiographies obtained with weight bearing. 52 of the 79 patients were men, and the mean age of the total materials was 34.6 years old (in the range $17{\sim}48$). Results: At follow-up, radiographic changes including Fairbank changes and joint space narrowing were seen from 45 of the 79 patients (56.2%). In other calculation, radiographic changes were seen in 23 out of 54 patients (42.6%) who had a partial meniscectomy, but were presented in 22 out of 25 patients (88.0%) who had a total meniscectomy. As a result, more radiographic changes were seen after total meniscectomy (p=0.03). In clinical results, 39 out of 54 patients (72.2%) after partial meniscectomy were satisfactory, and 14 out of 25 patients (56.0%) after total meniscectomy were satisfactory, therefore, more percentage of patients were satisfactory in partial meniscectomy group than in total meniscectomy group, but the statistical differences were absent (p=0.24). Conclusion: The frequency of radiographic changes in $10{\sim}15$ years after meniscectomy was related to the quantity of the meniscus removed, but the differences of these changes were low and had little influence on activity and knee function.

• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.3
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• pp.241-251
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• 2010

This study aims at contributing to the restorative dentistry by examining results in the vertical load test of four different low invasive fixed partial dentures. Based on a hypothesis on the right upper first molar is missing, three units of FPDs were made for the second premolar and the second molar abutment. that is, twelve metal dies and FPDs were made for resin bonded FPD and Two Key Bridges and Human Bridge without occlusal rest and Human Bridge with occlusal rest. By using universal test machine, the numerical maximum value were recorded during the vertical load test of each FPDs after the bonding process treated by Maxcem which is resin cement. The failure process and its result of prosthesis were also observed. The maximum load was 7,295 N, 4,729 N, 2,190 N, 3,073 N from groups of resin bonded FPD, Two Key Bridge, Human Bridge without occlusal rest and Human Bridge with occlusal rest respectively. There was a statistical significance among the groups of resin bonded FPD, Two Key Bridge and Human Brides. However, there was no significant difference between Human Bridge without occlusal rest and Human Bridge with occlusal rest. Regarding the failure of prosthesis, the groups of Resin Bonded FPD and Two Key Bridge showed that one of the abutment teeth in the both side of retention part was highly failed earlier than the other one (83.2% and 66.6% respectively). While, Human Bridge without occlusal rest and Human Bridge with occlusal rest showed high percentage of failure in the abutment teeth in the both side of retention part at the same time (91.6% and 58.3% respectively). This study demonstrates that the group of Human Bridges has low resistance to the vertical loads of low invasive FPDs in comparison with the groups of resin bonded FPD and Two Key Bridge. Nevertheless, the maximum occlusal load of the restorative position, resistance to diverse restoration failure, amount of tooth reduction and patients' cooperation should be considered when they are applied in the clinic in order to choose an appropriate restoration for each patient.