• Journal of Hydrogen and New Energy
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• v.27 no.2
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• pp.144-154
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• 2016

HT-PEMFC (high temperature polymer electrolyte membrane fuel cell) using PA (phosphoric acid) doped PBI (polybenzimidazole) membrane has been researched for extending the lifetime. However, the existing work on durability of HT-PEMFC focuses on identifying degradation causes of lab scale. The short life time of HT-PEMFC is still the problem for its commercialization. In this paper, an operating method to maximize life time of 5kW HT-PEMFC stack are proposed. The proposed method includes major steps such as minimization of OCV (Open Circuit Voltage) exposure, control of the proper stack temperature, and N2 purging for the stack. This long life operating method was based on the fragmentary results of degradation from previous research works. Experimentally, the 5 kW homemade HT-PEMFC stack was operated for a long time based on the proposed method and the stack successfully can operate within the desired degradation rate for the target life time.

• Transactions on Electrical and Electronic Materials
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• v.15 no.4
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• pp.201-206
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• 2014

LED lighting,considered to be a new growth industry, has attracted a great deal of attention due to its higher illumination and longer life time than existing light sources. In this study, high-efficiency and long-life LED fog lamps for automobiles were developed, which can substitute the existing 27 W halogen fog lamps for a used car market. For this purpose, the number of LED modules, the body, heat sink, and the output of the fog lamp were first optimized through a numerical analysis. Then, a 10 W-class LED fog lamp was prototyped based on the optimized numerical model, and the performance of the fog lamp was successfully verified through the experiments.

• Journal of Ocean Engineering and Technology
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• v.12 no.2 s.28
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• pp.71-78
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• 1998

In this report for the assessment of creep properties of high-temperature tube materials in power plants, the long-time($10^4$~105h) creep life prediction by ISM for 2.25Cr1Mo steel was studied. It was clarified experimentally and quantitatively that the newly developed long-time creep life prediction equation was very coincident with the actual experimental data with high confidence, and the model was $t_r=\alpha\varepsilon_0^{\beta}\sigma^{-1}$.

• Animal cells and systems
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• v.3 no.4
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• pp.355-358
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• 1999

Three novel species, Philodromus daoxianen n. sp., P. ganxiensis n. sp., and P. longitibiacus n. sp., are described based on the specimens collected from Hunan Province, China. P. daoxianen is similar to P. rufus, but its spermathecae is calabash-shaped, that of the latter spherical. It is also similar to P. kendrabatai, but differs in the form of atrium, distance between two spermathecae and dorsal markings of the abdomen. P. ganxiensis differs from other species of the genus Philodromus in eplgynum by a pair of sword-shaped apophyses, palpal organ with slightly wider distal end of a tibial apophysis, and knife-shaped membranous median apophysis. P. longitibiacus differs from other related species in long and thin palps and legs especially tibia of palps, which is about 4.5 times as long as the cybium and basal portion of embolus strongly sclerotized.

• Korean Journal of Bronchoesophagology
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• v.19 no.1
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• pp.11-14
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• 2013

Gastro-esophageal reflux disease (GERD) is a recurrent, long-term gastrointestinal condition characterised by the abnormal reflux of stomach contents into the esophagus. Heartburn is the most dominant symptom, which can be life long and can considerably reduce quality of life. The main goals of treatment are to alleviate symptoms and prevent relapses, esophageal stricture and adenocarcinoma. This paper presents a review comparing the effectiveness of omeprazole with Nissen fundoplication surgery for the treatment of GERD. Nissen fundoplication is more effective in controlling heartburn symptoms, healing esophagitis and preventing relapses than omeprazole. Quality of life, in terms of productivity and ability to work, is difficult to assess in the omeprazole group and, as a result, a comparison of this aspect is limited. Although fundoplication is expensive in the short term, it is more cost-effective than omeprazole. Nurses need to be aware of the effectiveness of omeprazole and fundoplication to provide patients with accurate information, which assists patients in decision making regarding treatment options.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1999.10a
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• pp.249-256
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• 1999

This study is intended to propose a systematic procedure for the development of the reliability-based seismic safety and cost-effective Performance criteria for design and upgrading of long span PC bridges. In the paper, a set of cost function models for life cycle cost analysis of bridges is proposed. The total life cycle cost functions consist of initial cost and direct/indirect damage costs considering repair/replacement costs, human losses and property damage costs, road user costs, and indirect regional economic losses. The damage costs are successfully expressed in terms of Park-Ang median global damage indices and damage probabilities. The proposed approach is successfully applied to model bridges in both regions of a moderate seismicity area like Seoul, Korea and a high one like Tokyo, Japan. It may be expected that the proposed approach can be effectively utilized for the development of cost-effective performance criteria for design and upgrading of various types of bridges as well as long span PC bridges.

• Radiation Oncology Journal
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• v.38 no.2
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• pp.84-92
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• 2020

Patients undergoing radiation therapy for head and neck cancer (HNC) experience significant early and long-term side effects. The likelihood and severity of complications depends on a number of factors, including the total dose of radiation delivered, over what time it was delivered and what parts of the head and neck received radiation. Late side effects include: permanent loss of saliva; osteoradionecrosis; radiation recall myositis, pharyngoesophageal stenosis; dental caries; oral cavity necrosis; fibrosis; impaired wound healing; skin changes and skin cancer; lymphedema; hypothyroidism, hyperparathyroidism, lightheadedness, dizziness and headaches; secondary cancer; and eye, ear, neurological and neck structures damage. Patients who undergo radiotherapy for nasopharyngeal carcinoma tend to suffer from chronic sinusitis. These side effects present difficult challenges to the patients and their caregivers and require life-long strategies to alleviate their deleterious effect on basic life functions and on the quality of life. This review presents these side effects and their management.

• Genomics & Informatics
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• v.16 no.4
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• pp.30.1-30.6
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• 2018

There is urgent need for effective and cost-efficient data storage, as the worldwide requirement for data storage is rapidly growing. DNA has introduced a new tool for storing digital information. Recent studies have successfully stored digital information, such as text and gif animation. Previous studies tackled technical hurdles due to errors from DNA synthesis and sequencing. Studies also have focused on a strategy that makes use of 100-150-bp read sizes in both synthesis and sequencing. In this paper, we a suggest novel data encoding/decoding scheme that makes use of long-read DNA (~1,000 bp). This enables accurate recovery of stored digital information with a smaller number of reads than the previous approach. Also, this approach reduces sequencing time.

• Animal Bioscience
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• v.37 no.2
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• pp.203-209
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• 2024

Objective: This study aimed to assess the impact of the dilution ratio of Tris diluent, storage at 0℃, and long-distance transportation on the spermatozoa of Simmental cattle. It also validated the feasibility of the regional distribution of fresh semen. Methods: In experiment 1, semen was diluted at four dilution ratios (1:6, 1:9, 1:12, and 1:15) to determine the optimal dilution ratio of Tris diluent. In experiment 2, we assessed sperm viability, progressive motility (objectively assessed by computer-assisted sperm analyzer), and acrosome intactness in Tris dilutions kept at constant 0℃ for 1, 3, 6, 9, and 12 days. We compared them to Tianshan livestock dilutions (Commercial diluent). In experiment 3, semen was diluted using Tris diluent, and sperm quality was measured before and after long-distance transport. Artificial insemination of 177 Simmental heifers compared to 156 using Tianshan Livestock dilution. Results: The outcomes demonstrated that 1:9 was the ideal Tris diluent dilution ratio. The sperm viability, Progressive Motility, and acrosome integrity of both Tris and Tianshan dilutions preserved at 0℃ gradually decreased over time. sperm viability was above 50% for both dilutions on d 9, with a flat rate of decline. The decrease in acrosome integrity rate was faster for Tianshan livestock dilutions than for Tris dilutions when stored at 0℃ for 1 to 6 days. There was no significant difference (p>0.05) in sperm viability between semen preserved in Tris diluent after long-distance transportation and semen preserved in resting condition. The conception rates for Tris dilution and Tianshan livestock dilution were 49.15% and 46.15% respectively, with no significant difference (p>0.05). Conclusion: This shows that Tris diluent is a good long-term protectant. It has been observed that fresh semen can be successfully preserved for long-distance transport when stored under 0℃ conditions. Additionally, it is feasible to distribute semen regionally.

• Korean Journal of Head & Neck Oncology
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• v.16 no.2
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• pp.191-195
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• 2000

Objectives: Despite various attempts to preserve the normal voice in advanced laryngeal cancer, it is inevitable for many advanced laryngeal cancer patients to undergo total laryngectomy and thus making a trade off between quality and quantity of life. Laryngectomees are faced with voice loss, change in physical appearance and health deterioration which hinder their efforts to rehabilitate back into their family and employment leading to poor quality of life. The objectives of this study were to evaluate the quality of life in long term surviving laryngectomees to, define the factors which are most important in determining their present quality of life and to propose a theoretical model for quality of life after laryngectomy in Korea. Materials and Methods: From 1986 to 1995, 120 laryngectomees with no evidence of disease were followed up for at least 3years were evaluated. Each of 15 quality of life domains with a total of ten points were given for a quality of life score. Results: There was no significant difference in the physical-mental adaptation index such as general health and mental health between the laryngectomees and control group(p>0.05). However, social adaptation index such as social activity, occupational status and economic status for laryngectomees were significantly lower with 2.3, 3.5, and 4.4 points compared to control group with 8.5, 7.6, and 7.1 points respectively(p<0.05). Conclusion : Vocational and social rehabilitation should be emphasized with highest priority for improving their economic status and thus improving their quality of life.