• Title/Summary/Keyword: Comparison of reducing characteristics

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Evaluation of Vibration Characteristics around the Conventional, Turnout System through the Field Measurements (현장측정을 통한 분기기시스템 주변의 진동특성 평가)

  • Kim, Young-Ha;Eum, Ki-Young;Shin, Min-Ho;Park, Yong-Gul
    • Proceedings of the KSR Conference
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    • 2008.11b
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    • pp.1000-1005
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    • 2008
  • A turnout system which permits trains to pass from one track to another is a combination of the switch, the crossing, lead rails which are necessary to connect the switch and the crossing, two guard rails and switch machines for operating the switch. A turnout is the sole moving part among the railway components and has complex configuration, so the safety has always been raised an issue. In Korea, it is planned to adopt the high speed tilting train, which operates at the maximum speed of 180km/h, at conventional lines. However, for the application of the tilting train to conventional lines, it is prerequisite to establish a stable turnout system allowing the tilting train to pass through it without reducing speed. Therefor, the improved turnout system for the speed-up of conventional lines has been developed and the prototype of the turnout system has been constructed. In this study, evaluation of Vibration characteristics around the improved turnout system was performed through the field measurements. Field measurements of Vibration around the conventional and the high-speed turnout system were also carried out for the comparison.

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Family Caregivers of the Impaired Elderly: A Comparison between Spouses and Adult Children (장기요양노인 가족수발자의 부양 실태에 관한 연구: 배우자 수발자와 자녀 수발자의 비교를 중심으로)

  • Shin, Kkot-Shi-Gye;Han, Gyoung-Hae
    • The Korean Journal of Community Living Science
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    • v.22 no.1
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    • pp.35-51
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    • 2011
  • This study examined how caregiving experiences of spouses and adult children were different to each other in terms of caregiver characteristics, the impairment level of the elderly, caregiving time, caregiver burden, the effects of long-term care services, etc. Data were collected from 321 spouses and 324 adult children who cared for the functionally and/or cognitively impaired elderly using long-term care services. The main results are as follows. (1) Caregiver characteristics differed significantly between spouses and adult children. (2) Adult children cared for the more severely impaired elderly in terms of IADL, cognitive impairment, and behavior problems while spouses spent more time helping in ADL activities. (3) Spouse caregivers experienced greater overall burden, worry and strain, and financial burden compared to adult child caregivers. (4) Long-term care services were effective in reducing caregiver burden and improving family relations. Additionally, relations between adult child caregivers and the elderly was more improved than relations between spouse caregivers and the elderly after using long-term care services. Based on these findings, the differential experiences between spouse caregivers and adult child caregivers were discussed.

Dosimetric comparison between modulated arc therapy and static intensity modulated radiotherapy in thoracic esophageal cancer: a single institutional experience

  • Choi, Kyu Hye;Kim, Jina;Lee, Sea-Won;Kang, Young-nam;Jang, HongSeok
    • Radiation Oncology Journal
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    • v.36 no.1
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    • pp.63-70
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    • 2018
  • Purpose: The objective of this study was to compare dosimetric characteristics of three-dimensional conformal radiotherapy (3D-CRT) and two types of intensity-modulated radiotherapy (IMRT) which are step-and-shoot intensity modulated radiotherapy (s-IMRT) and modulated arc therapy (mARC) for thoracic esophageal cancer and analyze whether IMRT could reduce organ-at-risk (OAR) dose. Materials and Methods: We performed 3D-CRT, s-IMRT, and mARC planning for ten patients with thoracic esophageal cancer. The dose-volume histogram for each plan was extracted and the mean dose and clinically significant parameters were analyzed. Results: Analysis of target coverage showed that the conformity index (CI) and conformation number (CN) in mARC were superior to the other two plans (CI, p = 0.050; CN, p = 0.042). For the comparison of OAR, lung V5 was lowest in s-IMRT, followed by 3D-CRT, and mARC (p = 0.033). s-IMRT and mARC had lower values than 3D-CRT for heart $V_{30}$ (p = 0.039), $V_{40}$ (p = 0.040), and $V_{50}$ (p = 0.032). Conclusion: Effective conservation of the lung and heart in thoracic esophageal cancer could be expected when using s-IMRT. The mARC was lower in lung $V_{10}$, $V_{20}$, and $V_{30}$ than in 3D-CRT, but could not be proven superior in lung $V_5$. In conclusion, low-dose exposure to the lung and heart were expected to be lower in s-IMRT, reducing complications such as radiation pneumonitis or heart-related toxicities.

Comparison of the major compounds and antimicrobial activities of Koara garlic cultivated in different regions (산지별 고아라 마늘의 주요 성분과 항균활성 비교)

  • Kim, Ju-Sung;Ra, Jong Hwan
    • Korean Journal of Food Science and Technology
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    • v.51 no.3
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    • pp.258-262
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    • 2019
  • Although the chemical compositions and biological characteristics of some species of garlic have been investigated, data on Koara garlic are currently lacking. In order to investigate the major compounds and antimicrobial activity of Koara garlic, which was registered as a cultivar in 2012, it was cultivated in Seogwipo, Damyang, and Namhae. Analysis of the chemical composition of the cultivated garlic showed that the alliin, pyruvate contents, and antimicrobial activity were high in garlic grown in Seogwipo ($9.44{\pm}0.28mg/g$, $127.52{\pm}5.50{\mu}M/g$, and 0.31-1.25%, respectively). The total phenol content and reducing sugar contents were abundant in garlic grown in Namhae ($82.23{\pm}0.00g\;GAE/100g$ and $28.59{\pm}0.54mg\;GE/g$, respectively), and the total flavonoid content was high in garlic grown in Damyang ($22.41{\pm}0.77g\;QE/100g$). Although garlics grown in different cultivation areas had different chemical compositions, major compound contents and biological activities of Koara garlic were similar to those of other garlic varieties reported so far. These data will be useful for local farmers, distributors, and consumers.

Design of the Near Field Microwave Guide Type of Probe Having Enhanced High Transmission Efficiency and Smaller Beam Spot Area (고 투과 효율과 소형 빔 스팟 면적을 갖는 근접장 마이크로웨이브 도파관 탐침의 설계)

  • Ko, Ji-Hwan;Cho, Young-Ki
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.26 no.12
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    • pp.1058-1063
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    • 2015
  • In this article, we propose a near field microwave scanning probe structure in which two short conducting rods are attached to the center of the ridged(H-type) aperture, thereby reducing significantly the beam spot area while maintaining the high transmission efficiency through the output coupling H-type(ridged) aperture. Here the two short parallel conducting rods seem to play an important role of concentrating the transmitted electromagnetic energy through the H-type aperture and so reducing the beam area for high resolution. For validation of the proposed theory, the near field waveguide probe is fabricated according to the simulated results and its return loss characteristics versus frequencies are measured. The comparison between theory and experiment is seen to be in good agreements.

Antioxidant and Antimicrobial Activities of Sorghum Germplasms Introduced from USA (미국 도입 수수 유전자원의 항산화활성과 항균활성)

  • Goh, Eun-Jeong;Yoo, Ji-Hye;Seong, Eun-Soo;Lee, Jae-Geun;Hwang, In-Seong;Kim, Nam-Jun;Yu, Chang-Yeon
    • Korean Journal of Plant Resources
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    • v.25 no.2
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    • pp.193-199
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    • 2012
  • This study was carried out to evaluate the agronomic characteristics and biological activities of $Sorghum$ $bicolor$ germplasms introduced from USA. Plant height, stem diameter, tiller number, leaf length, leaf width, leaf vein color, ear type, ear length and ear width have different from the cultivated accessions. Sweet-N-Sterile (#4) showed the tallest height, widest ear-width and stem diameter. Most of $Sorghum$ $bicolor$ plants may be available to use for bio-energy from these results showing big biomass. Antioxidant activities of 11 cultivars collected from USA were examined by DPPH assay and reducing power. Among the cultivars, Premium stock (#1), Early Sumac (#7), SS Silage (#9) and WGF Grain Sorghum (#11) showed a significantly higher antioxidant activity in comparison to others. Early Sumac (#7) and SS silage (#9) showed more strong reducing power activities than ${\alpha}$-tocopherol, a positive control. Premium stock (#1), Sweet-N-Sterile (#4), Early Sumac (#7) and SS Silage (#9) were also showed high antioxidant activities by DPPH assay and reducing power experiment. BMR Gold I (#3) displayed strong antimicrobial activity against $Escherichia$ $coli$ at minimum inhibitory concentrations (125 ${\mu}g$/ml).

Overview of the Development of the Korean Exposure Factors Handbook

  • Jang, Jae-Yeon;Jo, Soo-Nam;Kim, So-Yeon;Myung, Hyung-Nam
    • Journal of Preventive Medicine and Public Health
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    • v.47 no.1
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    • pp.1-6
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    • 2014
  • A set of exposure factors that reflects the characteristics of individual behavior capable of influencing exposure is essential for risk and exposure assessment. In 2007, the Korean Exposure Factors Handbook was, therefore, issued, driven by the need to develop reliable exposure factors representing the Korean population. The purpose of this study was to overview the development process of the Korean Exposure Factors Handbook and major recommended exposure values for the Korean population to allow information exchanges and comparison of recommended values among nations. The researchers reviewed the domestic data that could be used in the development of exposure factors, confirmed a knowledge gap, and set a priority of development by phases. A methodology to measure exposure factors was established to develop measuring techniques and test their validity. Data were processed or a survey was conducted according to the availability of data. The study thus produced recommended values for 24 exposure factors grouped by general exposure factors, food ingestion factors, and activity factors by setting up a database of exposure factors and carrying out statistical analysis. The study has significantly contributed to reducing the potential uncertainty of the risk and exposure assessment derived by the application of foreign data or research findings lacking representativeness or grounds by developing a set of exposure factors reflecting the characteristics of the Korean people. It will be necessary to conduct revisions in light of the changing statistical values of national data and the exposure factors based on Korean characteristics.

A Comparison of Muscle Contraction Using Functional Electrical Stimulation: Intermittent High Frequency Alternating Stimulation Versus Intermittent Low Frequency Synchronous Stimulation (기능적 전기자극기를 이용한 간헐적 고주파 교대자극과 간헐적 저주파 동시자극의 근 수축력 비교)

  • Song, Young-Hee;Cho, Sang-Hyun;Lee, Young-Hee
    • Physical Therapy Korea
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    • v.9 no.2
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    • pp.115-131
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    • 2002
  • Functional electrical stimulation (FES) training of the knee extensors is a useful way to rehabilitate the ability to stand and walk. However, training using FES has not been able to solve the problem of fatigue; clinical application of FES quickly produces muscle fatigue, due to the continuous activation of the muscles of the lower extremity. Therefore, reduction of muscle fatigue is an important factor in increasing the effectiveness of FES training in paraplegia. Intermittent high frequency alternating stimulation is a method that combines the advantages of high frequency (leading to strong muscle contractions) and alternating stimulation (reducing muscle fatigue), thereby continuously strengthening muscles. It is not known whether low frequency simultaneous stimulation results in stronger muscle contraction than high frequency alternating stimulation. This study compared the effectiveness of high frequency alternating stimulation with low frequency synchronized stimulation. Muscle power using FES on the quadriceps of 20 normal subjects were compared. Intermittent high frequency alternating stimulation did not produce more powerful muscle contraction than intermittent low frequency synchronized stimulation, because the muscle characteristics differed individually. Significant individual variation according to muscle characteristics was founded when applying FES. Accordingly, when physical therapists use FES to treat patients, they must be aware of individual variation in muscle characteristics.

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Quality Characteristics of Sulgidduck prepared by Addition of Astringent Persimmon Powder (떫은감 분말을 첨가한 설기떡의 품질특성)

  • Kim, Gwi-Young;Moon, Hye-Kyung;Lee, Su-Won
    • Food Science and Preservation
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    • v.13 no.6
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    • pp.697-702
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    • 2006
  • This study investigated the quality characteristics of sulgidduck prepared by the addition of astringent persimmon powder. For Sulg : dduck, the amounts of added astringent persimmon powder were 0, 5, 10, 15, 20%. With the addition of astringent persimmon powder content the moisture content of persimmon sulgidduck (sulgidduck prepared by adding astringent persimmon powder) decreased. With increasing addition of those, Reducing sugar, free sugar and mineral (Ca, K and Mg) of persimmon sulgidduck were increased significantly. L-value in color decreased whereas a- and b-values were increased. Adhesiveness, cohesiveness, gumminess and chewiness in textural profile analysis were decreased. However, there is no respective comparison hole. These result suggest that persimmon sulgidduck can be used as rice cakes commercially desired.

An Experimental Study on the Combustion Characteristics in Low Emission Multi-Staged Oil Burner (다단연소를 이용한 저 NOx 버너의 연소특성에 관한 연구)

  • An, Guk-Yeong;Kim, Han-Seok;Jo, Eun-Seong
    • 연구논문집
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    • s.27
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    • pp.101-108
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    • 1997
  • The characteristics of combustion and emissions in multi-staged oil burner have been experimentally studied for the various range of equivalence ratios, drop sizes and fuel formulations. Malvern system was used to measure droplet size of fuel. Light fuel oil and light fuel oil doped with pyridine($C_5H _5N$) were used to investigate the effects on fuel NOx emission. The emissions of NO and CO in exhaust gas and the flame temperatures were measured by the gas analyzer and thennocouples. NOx emissions were increased by increasing the excess air ratio (range:$lambda=1.1-1.4$) or decreasing the SMD of droplet in single-staged burner. In comparison with the single-staged burner, the emission of NOx in multi-staged burner was reduced by 50% but CO emission was slightly increased. It is found that multi-staged burner has a good capability in reducing thermal NOx resulting from the distributed heat release rate and lower flame temperature in fuel-rich and fuel-lean combustion zone. Moreover, the fuel NOx emission of the multi-staged burner is lower than that of single-staged burner, because multi-staged burner has fuel rich zone where fuel N is converted to $N_2$ more than NO. In 3-staged burner, the percentage of each stage combustion air have strong influence on emission characteristics. It is also found that NOx emission can be reduced by decreasing inner and outer air percentage or increasing middle air flow rate and CO emission is vice versa.

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