• Title/Summary/Keyword: 4DT

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A New Implementable Scheduling Algorithm Supporting Various Traffics in ATM Networks (ATM 망에서 다양한 트래픽을 지원하기 위한 동적 셀 스케줄링 알고리즘)

  • 심재정;이원호;변재영;고성제
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.4B
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    • pp.675-682
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    • 2000
  • In this paper, we propose a new scheduling algorithm called the Adaptive Weighted Round Robin with Delay Tolerance (AWRR/DT). The proposed scheme is based on the per-class queueing mechanism in which a number of connections of similar characteristics are multiplexed into one class-queue. Traffic classes of the proposed method are classified into a single non-real-time traffic class and other real-time traffic classes. The proposed scheme determines the weights of classes according to the input traffic and delay characteristics of each class at the beginning of every cycle. Furthermore, this scheme incorporates a cell discarding method to reduce the QoS degradation that may be incurred by congestion of networks. We have evaluated the proposed scheme through discrete-event simulation. Simulation results indicate that the proposed scheme can reduce the average delay of non-real-time class while maintaining the QoS of real-timeclasses. The proposed algorithm can be effectively applied to high-speed networks such as ATM networks.

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A Study on the High Temperature Creep Crack Growth Properties for Steam Turbine Rotor Steel under Static and Cyclic Loading Condition (화력 발전용 고압 로터강의 정하중 및 변동하중하의 고온 크립 균열전파 특성에 관한 연구)

  • O, Se-Gyu;Jeong, Sun-Eok
    • Journal of Ocean Engineering and Technology
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    • v.5 no.2
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    • pp.207-207
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    • 1991
  • The crack length measurements by electrical potential(EP) method for 1% Cr-Mo-V and 12%Cr steel of 0.5T-CT specimen were performed at $500^{\circ}C, 600^{\circ}C 700^{\circ}C$, and an applicability of stress intensity factor($K_I$), net section stress($\sigma_{net}$), $C^*$-ingegral and $C_t$ parameter was studied to measure creep crack growth rate(da/dt) with side groove and without side groove under static and cyclic loading condition. The experimental result could be summarized as follows: 1) Crack measurement by EP method was available and coincided with the Johnson,s analytical equation. 2) da/dt by $K_I$ and $\sigma_{net}$ was not adequate because of the wide scatter band according to load and temperature, but $C^*$-integral, except for transition region, was adequate. 3) $C_t$ parameter showed the best fitted line through total creep region without relating with both temperature and load condition. 4) Under the cyclic loading condition, $C_t$ parameter was proper to extimate da/dt. And it was shown that da/dt for 1% Cr-Mo V steel under the static condition(R=1) was 1.16 times faster than the case under cyclic loading(R=0), and for 12% Cr steel, 1.43 times.

A Study on the High Temperature Creep Crack Growth Properties for Steam Turbine Rotor Steel under Static and Cyclic Loading Condition (화력 발전용 고압 로터강의 정하중 및 변동하중하의 고온 크립 균열전파 특성에 관한 연구)

  • O, Se-Gyu;Jeong, Sun-Eok
    • Journal of Ocean Engineering and Technology
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    • v.5 no.2
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    • pp.67-75
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    • 1991
  • The crack length measurements by electrical potential(EP) method for 1% Cr-Mo-V and 12%Cr steel of 0.5T-CT specimen were performed at $500^{\circ}C, 600^{\circ}C 700^{\circ}C$, and an applicability of stress intensity factor($K_I$), net section stress($\sigma_{net}$), $C^*$-ingegral and $C_t$ parameter was studied to measure creep crack growth rate(da/dt) with side groove and without side groove under static and cyclic loading condition. The experimental result could be summarized as follows: 1) Crack measurement by EP method was available and coincided with the Johnson, s analytical equation. 2) da/dt by $K_I$ and $\sigma_{net}$ was not adequate because of the wide scatter band according to load and temperature, but $C^*$-integral, except for transition region, was adequate. 3) $C_t$ parameter showed the best fitted line through total creep region without relating with both temperature and load condition. 4) Under the cyclic loading condition, $C_t$ parameter was proper to extimate da/dt. And it was shown that da/dt for 1% Cr-Mo V steel under the static condition(R=1) was 1.16 times faster than the case under cyclic loading(R=0), and for 12% Cr steel, 1.43 times.

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Variation of the Germination Responses to Temperature of Plantago asiatica Seed Population along Altitude in Mt. Chiri (지리산에서 고도에 따른 질경이(Plantago asiatica) 개체군의 온도에 대한 발아습성의 변이)

  • Lee, Ho-Joon;Kim, Yong-Ok;Jeon, Jae-Hee;Seong, Mi-Seon;Jang, Il-Do
    • The Korean Journal of Ecology
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    • v.17 no.4
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    • pp.485-499
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    • 1994
  • This study was focused on the effect of the altitude on the geographical variations of germination characteristics in the populations of Plantago asiatica L. distribute in Mt. Chiri. There was a significant difference among the 14 groups in the phenological pattern in relation to altitudes. When the altitude becomes higher, the thermal time which was required for 10 to 80% germination rate showed higher and wider distribution. On the other hand, the germination response of increasing temperature (IT) and secreasing temperature (DT) regime was classified into 3 group. The first group was the spering germination type. This group showed that the IT regime hadhigher germination rate than that of the DT regime, and was distributed in Macheon(300m) and Packmudong (500m). The second was the spring-fall germination type which was distributed in Hadong (900m) and Saemt대 (1100m). This group also showed higher germination rate in the IT regime, but the difference of the germination rate between IT and DT regime was less than that in the first group (the spring type). The third group was the early fall germination type which was found in the Nogodan (1507m), Changetomok (1750m) and Cheonwangbong (1915m). The germination rate of this group showed almost 100% similarity between IT and DT regime. These data suggested that the geographical varations of germination characteristics within species was an important ecological strategy for the survival from severe environmental conditions.

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Effects of Added Corn Starches and Hydrocolloids on the Characteristics of Mungbean Starch and the Mook(Starch Gel) (옥수수 전분과 Hydrocolloids 첨가가 녹두 전분 및 묵의 특성에 미치는 영향)

  • Park, Ok-Jin;Kim, Kwang-Ok
    • Korean Journal of Food Science and Technology
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    • v.20 no.4
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    • pp.618-624
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    • 1988
  • This study was conducted to observe the effects of partial replacement of mungbean starch(MB) with dent(DT) or cross-linked(CL) corn starches, and of added hydrocolloids on the characteristics of mungbean starch and the mook. The replacement with CL caused less changes compared to that with DT in phase transition enthalpy of MB measured with defferential scanning calorimeter. The viscosity of MB paste cooled to $50^{\circ}C$ after heating was also affected less with CL than with DT. The addition of hydrocolloids to mixed starches of MB and CL did not affect initial viscosity increase but resulted in marked increase in viscosity at later stage of heating. Mixed monks with CL were more similar to MB monks than those with DT. Hydrocolloids added to MB-CL mixture further decreased the gap between monks with and without CL.

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Cryogenic Distillation Simulation for Hydrogen Isotopes Separation (수소 동위원소 분리를 위한 초저온증류공정 모사)

  • Noh, Sanggyun;Rho, Jaehyun;Cho, Jungho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.9
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    • pp.4643-4651
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    • 2013
  • In this study, we have surveyed the new technologies in the cryogenic distillation of ITER, equilibrium reactors and helium refrigeration cycle contained in the isotope separation system (ISS). We also have collected thermodynamic and transport properties for $H_2$, HD, $D_2$, HT, DT and $T_2$ components of which properties are not built in a general purpose chemical process simulators such as Aspen Plus and PRO/II with PROVISION. Verification works have been performed to compare between literature data and simulation results. For the simulation of ISS involving six hydrogen isotope components, four distillation columns and two equilibrium reactors are used for the separation of $D_2$ and DT from $T_2$.

Effects of Chiropractic Using Sacro Occipital Technique on Pain and Physical Function in Patients with Low Back Pain (천골후두골 테크닉을 이용한 카이로프랙틱이 만성 요통환자의 통증과 신체기능에 미치는 영향)

  • Jeong, Ji-Moon;Kim, Jaehee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.9
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    • pp.4402-4411
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    • 2013
  • The aim of this study was to identify the effects of chiropractic treatment using Sacro Occipital Technique (SOT) on low back pain (LBP) and physical functions in patients with chronic LBP. Forty-five women with chronic LBP were randomly assigned to the Diversified Technique (DT), SOT or DT+SOT group and received chiropractic treatment two times a week for 8 weeks. LBP was measured using Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), and Roland-Morris Disability Questionnaire (RMDQ) at baseline and after 4 and 8 weeks of treatment. Physical functions were evaluated using lumbar strength, flexibility, and body symmetries. After 4 and 8 weeks, VAS, ODI, and RMDQ were significantly decreased in all 3 groups (all p<.001). Lumbar strength, flexibility, and shoulder and pelvic balances were significantly improved in all 3 groups (all p<.05). In conclusion, our results suggest that SOT and DT both may be effective for reducing LBP and improving physical functions.

Distress and Associated Factors in Patients with Breast Cancer Surgery : A Cross-Sectional Study (유방암 수술환자의 디스트레스 및 연관인자 : 단면연구)

  • Lee, Sang-Shin;Rim, Hyo-Deog;Woo, Jungmin
    • Korean Journal of Psychosomatic Medicine
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    • v.26 no.2
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    • pp.77-85
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    • 2018
  • Objectives : This study aimed to investigate the level of distress using the distress thermometer (DT) and the factors associated with distress in postoperative breast cancer (BC) patients. Methods : DT and WHOQOL-BREF (World Health Organization Quality of Life Scale Abbreviated Version) along with sociodemographic variables were assessed in patients undergoing surgery for their first treatment of BC within one week postoperatively. The distress group consisted of participants with a DT score ${\geq}4$. The prevalence and associative factors of distress were examined by descriptive, univariable, and logistic regression analysis. Results : Three hundred seven women were recruited, and 264 subjects were finally analyzed. A total of 173 (65.5%) were classified into the distress group. The distress group showed significantly younger age (p=0.045), living without a spouse (p=0.032), and worse quality of life (QOL) as measured by overall QOL (p=0.009), general health (p=0.005), physical health domain (p<0.000), and psychological health domain (p=0.002). The logistic regression analysis showed that patients aged 40-49 years were more likely to experience distress than those aged ${\geq}60years$ (Odds ratios [OR]=2.992, 95% confidence interval [CI] 1.241-7.215). Moreover, the WHOQOL-BREF physical health domain was a predictive factor of distress (OR=0.777, 95% CI 0.692-0.873). Conclusions : A substantial proportion of patients are experiencing significant distress after BC surgery. It would be expected that distress management, especially in the middle-aged patients and in the domain of physical QOL (e.g., pain, insomnia, fatigue), from the early BC treatment stage might reduce chronic distress.

Transfer of R plasmids of Bacterial Isolates and Their Cloned R Genes in Natural Wastewater Environments (I) -Cloning of $Km^rCm^r$Gene- (하폐수의 자연환경에서 R plasmid와 재조합 유전자의 전이특성( I ) -$Km^rCm^r$유전자의 클로닝-)

  • 김치경;이성기
    • Microbiology and Biotechnology Letters
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    • v.17 no.5
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    • pp.447-453
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    • 1989
  • In order to study the transfer of antibiotics resistance genes of the genetically cloned bacteria in water environments, DK1 strain, which is resistant to kanamycin (Km), chloramphenicol (Cm), streptomycin (Sm), and sulfadiazine (Su), was selected from the Gram-negative bacterial isolates from wastewater. One of 4 plasmids harboured in the DK1 strain was found to possess Km$^{${\gamma}$}$Cm$^{${\gamma}$}$ gene and be about 68 kb in size, and it was designated as pDK101. The plasmid of pDK101 was also found to have 16, 32, and 6 restriction sites for EcoRI. .PstI, and SalI, respectively. From the digestion fragments of pDK101 plasmid and pKT230 used as a vector by EcoRI restriction endonuclease, pDT309 and pDT529 were constructed as chimeric plasmids which possess Km$^{${\gamma}$}$Cm$^{${\gamma}$}$ gene and are 30.9 and 52.9 kb in size, respectively. When the chimeric plasmids were trasformed into E. coli C600 or E. coli HB101, transformants of DKC601, DKC602, DKH102, and DKH103 were obtained as cloned bacterial cells. The Km$^{${\gamma}$}$Cm$^{${\gamma}$}$ genes were well expressed in those cloned cells and the chimeric plasmids were clearly detected in the cloned cells of DKC601 and DKH103.

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Relationship between Obesity and Dental Caries (비만과 치아우식증의 관계)

  • Lee, Sun-Hee
    • Journal of Digital Convergence
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    • v.12 no.12
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    • pp.633-641
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    • 2014
  • The purpose of this study was to grasp relationship between obesity and dental caries. A research was performed by utilizing raw data of the 3rd year(2009) in the 4th term for Korean National Health and Nutrition Examination Survey, which is a survey of health and nutrition in the national unit for the Republic of Korea. The research subjects are finally 7,393 people except the subjects with missing of variables relevant to obesity and dental caries among adults aged over fully 19 years old. Data analysis was used SPSS 18.0 program. As a result of analyzing with significant level in 0.05, the following conclusions were obtained. 1. Overweight(${\beta}$ = -0.12, p = .02) was indicated to be low in number of DT pieces compared to normality. 2. Obesity(OR = 0.69, 95% CI: 0.57, 0.84) was indicated to be low in possibility of having DMFT compared to normality. 3. Overweight(${\beta}$ = -0.39, p = .02) and obesity(${\beta}$ = -0.70, p<.0001) was indicated to be low in number of DMFT pieces compared to normality. And to conclude, obesity(body mass index) and dental caries(DT, DMFT) were found to have negative correlation. A significant result was indicated even after adjusting confounding variables.