• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5A
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• pp.467-475
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• 2009

Existing studies have suggested Universal Curve only for supplemental damping by damper. Therefore net damping has been determined by means of arithmetic summation between intrinsic, aero-damping of cable and supplemental damping of damper. However linear combination approach by means of the arithmetic summation is not enough theoretical background. So validity of this approach should be verified in order to design adequate cable-damper system by engineers. This study establishes governing differential equation which can consider intrinsic, aero-damping and supplemental damping as well. And also analysis method is solved by combination of muller method and successive iteration method. Consequently, this study succeeds in verification for validity of linear combination approach. As a result of this study, linear combination approach is limitedly effective in case of low stiffness and optimum damping coefficient of damper, short distance from support to damper, lower vibration mode, low aero-damping, and normal windy environment. Whereas this study will be effective in case of opposite conditions, and existing studies or linear combination approach occur to further error. Meaning of this study presents exact solution for net damping of cable-damper system, and verifies linear combination approach by means of the analysis method. In the future, if monitoring of optimum damping coefficient of a damper against aero-damping is feasible on time, algorithm of this study will be available for control of cable and semi-active damper system such as magneto-rheological damper.

• Journal of Venture Innovation
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• v.5 no.2
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• pp.85-99
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• 2022

Dryers becoming commercially available for experimental and industrial use are classified to general drying oven, hot-air dryer, vacuum dryer, freezing dryer, etc. and kinds of them are various from the function, size and volume, etc. But the moisture measurement is not applied although it is important factor for the quality control and the performance improvement of products, and then now is very passive because the weight is weighed arbitrarily after dry-end. Generally the method for measuring moisture is divided by a direct measurement method and a indirect measurement method, and the former such as the change of weight or volume on the front and rear of separation of moisture, etc. is mainly used. Relatively a indirect measurement is very limited to apply due to utilize measurement apparatuses using temperature conductivity and micro-wave etc. In this research, we easily designed the moisture measurement system using the open-source based Arduino, and monitored moisture fluctuations and weight profiles in the real-time without the effect of external environment. Concretely the temperature-humidity and load cell sensors were packaged into a drying oven and the various change values were measured, and their sensors capable to operate 60℃ and 80℃ were selected to suitable for the moisture sensitive materials and the food dry. And also the performance safety using the organic samples of banana, pear, sawdust could be secured because the changes of evaporation rate as the dry time and temperature, and the measurement values of load cell appeared stable response characteristics through repeated experiments. Hereafter we judge that the reliability can be improved increasingly through the expansion of temperature-humidity range and the comparative analysis with CFD(Computational Fluid Dynamics) program.

• Information Systems Review
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• v.15 no.2
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• pp.1-19
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• 2013

Smart working sparked by iPhone3 opens a revolution in smart ways of working at any time, regardless of location and environment. Also, It provide real-time information processing and analysis, rapid decision-making and the productivity of businesses, including through the timely response and the opportunity to increase the efficiency. As a result, every company are developing mobile information systems. But company data is accessed from the outside, it has problems to solve like security, hacking and information leakage. Also, Mobile devices such as smart phones belonging to the privately-owned asset can't be always controlled to archive company security policy. In the meantime, public smart phones owned by company was always applied security policy. But it can't not apply to privately-owned smart phones. Thus, this paper is focused to archive company security policy, but also enable the individual's free to use of smart phones when we use mobile information systems. So, when we use smart phone as individual purpose, the normal operation of all smart phone functions. But, when we use smart phone as company purpose like mobile information systems, the smart phone functions are blocked like screen capture, Wi-Fi, camera to protect company data. In this study, we suggest the design and implementation of real time control and management of mobile device using MDM(Mobile Device Management) solution. As a result, we can archive company security policy and individual using of smart phone and it is the optimal solution in the BYOD(Bring Your Own Device) era.

• Radiation Oncology Journal
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• v.19 no.2
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• pp.113-117
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• 2001

Purpose : To evaluate effect of postoperative radiotherapy on survival and local control for patients with non-small cell lung cancer (NSCLC). Materials and Methods : Ninety two NSCLC patients with N1or N2 involvement who were treated with postoperative radiotherapy following surgery with curative intent from May 1987 to October 1999 were retrospectively analyzed. Age of the patients was ranged from 32 to 78 years. According to TNM Stage, 35 patients had Stage II and 57 had Stage III disease. There were 49 patients with N1 involvement and 43 patients with N2 involvement. Fifty six patients were noted to have $T1\~2$ tumors and 36 patients to have $T3\~4$ tumors. Delivered total dose was ranged from 40 to 60 Gy. Majority of patients received 50 Gy or 50.4 Gy. Follow-up period was ranged from 9 month to 7 years with median follow-up of 26 months. Results : Overall survival rates at 3 and 5 years for entire group of patients were $46\%\;and\;38\%$, respectively. Corresponding disease free survival rates were $44\%\;and\;36\%$. There was significant difference in survival between patients with Stage II and Stage III disease ($50\%\;vs\;28\%$ at 5-year). Five year survival rates for N1 and N2 patients were $52\%\;and\;20\%$, respectively (p<0.05). These were $40\%\;and\;34\%$ for patients with $T1\~2$ tumors and $T3\~4$ tumors. There were documented local relapses in $13\%$ of the patients. For patients with N1 and N2 Stage, local relapse rates were $8\%\;and\;18\%$, respectively. Conclusion : Our study confirms that postoperative radiotherapy for patients with non-small cell lung cancer improves local control. However, influence of postoperative radiotherapy on long-term survival is less clear. More effective systemic treatment to prevent distant metastasis should be investigated in future study to improve long-term survival.

• Radiation Oncology Journal
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• v.15 no.3
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• pp.255-262
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• 1997

Purpose : This is retrospective study to compare the results of radiation therapy alone and neoadjuvant chemotherapy and radiation in advanced stage of uterine cervical cancer. Materials and Methods : Seventy-six Patients who were treated with definitive radiation therapy for locally advanced cervical cacinoma between June 1988 and December 1993 at the department of radiation oncology, Keimyung University Dong-san Hospital. Thirty six patients were treated with radiation therapy alone and forty patients were treated with cisplatin based neoadjuvant chemotherapy and radiation therapy. According to FIGO staging system. there were 48 patients in stage IIb, 3 patients in stage IIIa, 23 patients in stage lIIb and two patients in stage IVa with median age of 53 years old. Follow-up periods ranged from 7 to 95 months with median 58 months. Results : Complete response (CR) rate were $86.1\%$ in radiation alone group and $80\%$ in chemoradiation group. There was no statistical difference in CR rate between the two groups. Overall five-year survival rate was $67.3\%$. According to stage, overall five-rear survival rates were $74\%$ in stage IIb, $66.7\%$ in stage IIIa, $49.8\%$ in stage IIb, $50\%$ in stage IVa. According to treatment modality overall five year survival rates were $74.1\%$ in radiation alone and $61.4\%$ in chemoradiation group (P=0.4) Five rear local failure free survival rates were $71.5\%$ in radiation alone group and $60\%$ in chemoradiation group (P=0.17). Five year distant metastasis free survival rates were $80.7\%$ in radiation aione group and $89.9\%$ in chemoradiation group (P=0.42). Bone marrow suppression (more than noted in 3 cases of radiaion alone group and 1 case of chemoradiation group. Grade II retal complication was noted in 5 patients of radiation group and 4 patients In chemoradiation group. Bowel obstruction treated with conservative treatment (1 patient) and bowel perforation treated with surgery (1 patient) were noted in radiation alone group. There was no statistical difference in complication between two groups. Conclusion : There was no statistical difference in survival, failure and complication between neoadjuvant chemotherapy and radiation versus radiation alone in locally advanced uterine cervical carcinoma.

• Radiation Oncology Journal
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• v.26 no.1
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• pp.24-34
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• 2008

Purpose: To assess the efficacy of the use of accelerated hyperfractionated radiotherapy(AHRT) for locally advanced uterine cervix cancers. Materials and Methods: Between May 2000 and September 2002, 179 patients were identified with FIGO stage IIB, IIIB, and IVA cancers. Of the 179 patients, 45 patients were treated with AHRT(AHRT group) and 134 patients were treated with conventional radiotherapy(CRT group), respectively. Patients undergoing the AHRT regimen received a dose of 30 Gy in 20 fractions(1.5 $Gy{\times}2$ fractions/day) to the whole pelvis. Subsequently, with a midline block, we administered a parametrial boost with a dose of 20 Gy using 2 Gy fractions. Patients also received two courses of low-dose-rate brachytherapy, up to a total dose of 85{\sim}90 Gy to point A. In the CRT group of patients, the total dose to point A was $85{\sim}90$ Gy. The overall treatment duration was a median of 37 and 66 days for patients that received AHRT and CRT, respectively. Statistical analysis was calculated by use of the Kaplan-Meier method, the log-rank test, and Chi-squared test. Results: For patients that received cisplatin-based concurrent chemotherapy and radiotherapy, the local control rate at 5 years was 100% and 79.2% for the AHRT and CRT group of patients, respectively(p=0.028). The 5-year survival rate for patients with a stage IIB bulky tumor was 82.6% and 62.1% for the AHRT group and CRT group, respectively(p=0.040). There was no statistically significant difference for severe late toxicity between the two groups(p=0.561). Conclusion: In this study, we observed that treatment with AHRT with concurrent chemotherapy allows a significant advantage of local control and survival for locally advanced uterine cervix cancers.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.1
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• pp.19-27
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• 2012

The open-top chamber (OTC) system is designed for long term studies on the climate change impact on the major tree species and their community in Korea. In Korea Forest Research Institute (KFRI), the modified OTC system has been operating since September 2009. The OTC facility consists of six decagon chambers (10 meters in diameter by 7 meters high) with controlled gas concentration. In each chamber, a series of vertical vent pipes are installed to disperse carbon dioxide or normal air into the center of the chamber. The OTC is equipped with remote controlled computer system in order to maintain a stable and elevated concentration of carbon dioxide in the chamber throughout the experimental period. The experiment consisted of 4 treatments: two elevated $CO_2$ levels ($1.4{\times}$ and $1.8{\times}$ ambient $CO_2$) and two controls (inside and outdoors of the OTC). Average operational rate was the lowest (94.2%) in June 2010 but increased to 98% in July 2010 and was 100% during January to December 2011. In 2010~2011, $CO_2$ concentrations inside the OTCs reached the target programmed values, and have been maintained stable in 2011. In 2011, $CO_2$ concentrations of 106%, 100% and 94% of target values has been recorded in control OTC, $1.4{\times}$ $CO_2$-enriched OTC and $1.8{\times}$ $CO_2$-enriched OTC, respectively. With all OTC chambers, the difference between outside and inside temperatures was the highest ($1.2{\sim}2.0^{\circ}C$) at 10 am to 2 pm. Temperature difference between six OTC chambers was not detected. The relative humidity inside and outside the chambers was the same, with minor variations (0~1%). The system required the highest amount of $CO_2$ for operation in June, and consumed 11.33 and 17.04 ton in June 2010 and 2011, respectively.

• Radiation Oncology Journal
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• v.29 no.1
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• pp.20-27
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• 2011

Purpose: This study was designed to evaluate the results of local control, survival rate, prognostic factors, and failure pattern in locally advanced esophageal cancer. Materials and Methods: We retrospectively studied 50 patients with locally advanced esophageal cancer treated with concurrent chemoradiotherapy at Keimyung University Dongsan Medical Center from June of 1999 to August of 2008. Seven patients with inappropriate data were excluded, and 43 patients were analyzed. There were 39 males and four female patients ranging in age from 43 to 78 years (median, 63 years). There were seven patients with stage IIA and 36 with stage III. Irradiation from 46 Gy to 63 Gy (median, 54 Gy) was carried out 5 days per week, 1.8 Gy once a day. There were eight patients with neo-adjuvant chemotherapy, and we mostly used 5-fluorouracil, cisplatin with 3 cycles for concurrent chemotherapy. The range of follow up periods was from 2 to 82 months (median, 15.5). Results: There were nine patients that exhibited a cornplete response, 23 that exhibited a partial response, 9 that exhibited no response, and 2 that exhibited disease progression. The median survival time was 15 months. Two-year and 5-year survival rates were 36.5% and 17.3%, respectively. Two-year and 5-year disease-free survival rates were 32.4% and 16%, respectively. Treatment failure occurred in 22 patients (51.2%). Patterns of failure were categorized as local failure in 18 patients and distant metastasis in four patients. In a univariate analysis for prognostic factors related to overall survival and disease-free survival, the hemoglobin levels during chemoradiotherapy (${\geq}$ 12 vs. <12, p=0.02(p=0.1) and the response to the treatments (CR/PR vs. NR/PD, p=0.002/p< 0.0001) were statistically significant. In a multivariate analysis, only response to the treatments was revealed to be statistically significant. There was no statistical significance associated with patient age, gender, disease stage, T-stage, smoking history, tumor location, or neo-adjuvant chemotherapy. Conclusion: Our survival rate was similar to those of other institutions. Local recurrence was the main reason for failure. It is suggested that further prospective studies should be performed to improve local control.

• Fashion & Textile Research Journal
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• v.24 no.6
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• pp.667-685
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• 2022

This paper aims to investigate 4D printing materials for soft robots. 4D printing is a targeted evolution of the 3D printed structure in shape, property, and functionality. It is capable of self-assembly, multi-functionality, and self-repair. In addition, it is time-dependent, printer-independent, and predictable. The shape-shifting behaviors considered in 4D printing include folding, bending, twisting, linear or nonlinear expansion/contraction, surface curling, and generating surface topographical features. The shapes can shift from 1D to 1D, 1D to 2D, 2D to 2D, 1D to 3D, 2D to 3D, and 3D to 3D. In the 4D printing auxetic structure, the kinetiX is a cellular-based material design composed of rigid plates and elastic hinges. In pneumatic auxetics based on the kirigami structure, an inverse optimization method for designing and fabricating morphs three-dimensional shapes out of patterns laid out flat. When 4D printing material is molded into a deformable 3D structure, it can be applied to the exoskeleton material of soft robots such as upper and lower limbs, fingers, hands, toes, and feet. Research on 4D printing materials for soft robots is essential in developing smart clothing for healthcare in the textile and fashion industry.

• Journal of Life Science
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• v.33 no.12
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• pp.1015-1024
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• 2023

Antibiotics have greatly contributed to the treatment and prevention of bacterial diseases in humans, animals, and fish. However, antibiotic misuse has led to the emergence and spread of multidrug-resistant bacteria. In addition to antibiotic discovery research, efforts are being made to combat such multidrug-resistant bacteria using antimicrobial agents, antioxidants, host immune enhancement, probiotics, and bacteriophages, as well as various symptomatic therapies. To discover novel bioactive compounds, it is crucial to adopt approaches that incorporate fresh ideas, new targets, innovative techniques, and untapped resources. Halophytes are plants that grow in high-salt soils and are known to adapt to salt-induced stress through unique metabolic processes that produce secondary metabolites. This study aimed to investigate the effects of extracts of halophytes native to Korea on oxidative stress and to determine whether they exert inhibitory activity against biofilms, which are major pathogenic factors of infectious bacteria. The Acinetobacter baumannii strain ATCC 17978, a representative drug-resistant bacterium, was used to measure anti-biofilm activity. The results showed that Aster spathulifolius, Carex kobomugi, Rosa rugosa, and Asparagus cochinchiensis exerted strong antioxidant and anti-biofilm effects without affecting bacterial growth itself. The halophytes used in this study are promising candidates for the development of pharmaceutical agents with antioxidant and antimicrobial properties.