• Title/Summary/Keyword: Response indices

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Analytical fragility curves for typical Algerian reinforced concrete bridge piers

  • Kibboua, Abderrahmane;Naili, Mounir;Benouar, Djillali;Kehila, Fouad
    • Structural Engineering and Mechanics
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    • v.39 no.3
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    • pp.411-425
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    • 2011
  • This paper illustrates the results of a seismic vulnerability study aimed to derive the fragility curves for typical Algerian reinforced concrete bridge piers using an analytical approach. Fragility curves express the probability of exceeding a certain damage state for a given ground motion intensity (e.g., PGA). In this respect, a set of 41 worldwide accelerometer records from which, 21 Algerian strong motion records are included, have been used in a non-linear dynamic response analyses to assess the damage indices expressed in terms of the bridge displacement ductility, the ultimate ductility, the cyclic loading factor and the cumulative energy ductility. Combining the damage indices defined for 5 damage rank with the ground motion indices, the fragility curves for the bridge piers were derived assuming a lognormal distribution.

Estimation of Fastened Condition of Bolts Using PZT Patches (압전소자를 이용한 볼트체결 상태계측 및 측정)

  • Chae, Kwan-Seok;Ha, Nam;Hong, Dong-Pyo;Chae, Hee-Chang
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2004.11a
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    • pp.889-893
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    • 2004
  • This work presents a study on development of a practical and quantitative technique for assessment of the structural health condition by piezoelectric impedance-based technique associated with longitudinal wave propagation method. The bolt fastening condition is adjusted by torque wrench. In order to estimate the damage condition numerically, three damage indices, impedance peak frequency shift ${\Delta}F$ is proposed in this paper. Furthermore, an assessment method is described for estimation of the damage by using these three damage indices.

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Effects of Buckwheat, Potato and Rice on Glycemic Indices in Healthy Subjects

  • Koh, Eun-Sook T.;Ju, Jin-Soon;Choi, Moon-Gi;Yoon, Tae-Heon;Ahn, Young-Sook;Lim, Kyung-Ja;Kim, Soon-Ok;Kim, Jong-Dai
    • Korean Journal of Medicinal Crop Science
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    • v.10 no.4
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    • pp.253-258
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    • 2002
  • We compared the long-term metabolic effects of equal amounts of carbohydrate from potato, rice and buckwheat on glycemic indices and blood lipids in healthy subjects. Nine healthy volunteers-2 men and 7 women were studied. All subjects ate diets based on the same-7-day rotating menu differing only in that the major source of carbohydrate (about 50% of daily total calories) came either from buckwheat, rice or potato. The study was conducted with a triple crossover design over three 7 day periods. On the morning of the 8th day, fasting blood was drawn from each subject to determine serum glucose, insulin, triglycerides, total and HDL-cholesterol. Subjects were then asked to eat breakfast with their respective carbohydrate within a 20 min period. Blood samples were drawn at 30, 60, 120 and 180 min after the start of breakfast to determine glucose and insulin levels. At 30 min the glucose response to the rice meal(7.15mmol/L) and potato meal(6.71mmol/L) were greater than the response to the buckwheat meal(5.855mmol/L) (P < 0.05). The mean area under the glucose response to the curve following the rice meal was greater than that following the buckwheat meal(P < 0.05). The insulin responses to the potato and rice meals at 30 and 60 min were greater than those to the buckwheat meal (P < 0.05). The mean area under the serum insulin response curve after the rice meal was greater than of buckwheat. Blood lipids, uric acid and glycosylated hemoglobin were not affected by the three meals. The study shows that the buckwheat meal has more beneficial effects on glycemic indices than either the rice meal or potato meal in healthy subjects.

Relationships of Psychological Factors to Stress and Heart Rate Variability as Stress Responses Induced by Cognitive Stressors (스트레스에 대한 심리 반응 유형과 심박변이도의 관련성)

  • Jang, Eun Hye;Kim, Ah Young;Yu, Han Young
    • Science of Emotion and Sensibility
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    • v.21 no.1
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    • pp.71-82
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    • 2018
  • Stress involves changes in behavior, autonomic function and the secretion of hormones. Autonomic nervous system (ANS) contributes to physiological adaptive process in short durations. In particular, heart rate variability (HRV) analysis is commonly used as a quantitative marker depicting the ANS activity related to mental stress. The aim of this study is to investigate correlations between psychological responses to stress and HRV indices induced by the cognitive stressor. Thirty-three participants rated their mental and physical symptoms occurred during the past two weeks on Stress Response Inventory (SRI), which is composed of seven stress factors that may influence the status of mental stress levels. Then, they underwent the psychophysiological procedures, which are collected electrocardiogram (ECG) signals during a cognitive stress task. HRV indices, the standard deviation of R-R interval (SDNN), root mean square of successive R-R interval difference (RMSSD) and low frequency (LF)/high frequency (HF) ratio were extracted from ECG signals. Physiological responses were calculated stress responses by subtracting mean of the baseline from the mean of recovery. Stress factors such as tension, aggression, depression, fatigue, and frustration were positively correlated to HRV indices. In particular, aggression had significant positive correlations to SDNN, RMSSD and LF/HF ratio. Increased aggressive responses to stress correlated with the increases of all HRV indices. This means the increased autonomic coactivation. Additionally, tension, depression, fatigue, and frustration were positively associated with RMSSD reflecting increases in parasympathetic activation. The autonomic coactivation may represent an integrated response to specific cognitive reactions such as the orienting response.

RELATIONSHIPS BETWEEN ENSO AND DROUGHTS IN KOREA AND THE CONTINENTAL U.S.

  • Lee, Dong-Ryu;Jose D. Salas
    • Water Engineering Research
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    • v.2 no.2
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    • pp.139-148
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    • 2001
  • The teleconnections between El Nino/Southern Oscillation (ENSO) and droughts in Korea and the continental United States(U.S.) are investigated using cross analysis. For this purpose, monthly ENSO data and Palmer Drought Severity Index (PDSI) for Korea and for seven states in the U.S. are used. This study shows that there are significant statistical associations between ENSO indices and PDSI for Korea; however, the associations are very weak. It is found that dry conditions in Korea are positively correlated with El Nino, while wet conditions with La Nina. SOI, SSt in the Nino 4 and Ship track 6 regions among ENSO indices are more strongly correlated with PDSI than the other ENSO indices when using the original standardized data, but the SST Nino 3, SST Nino 4, and Darwin SSP exhibit abetter correlations with PDSI when using filtered data to be removed autocorrelation components of the original standardized data. The response time lag for maximum correlation between ENSO indices and PDSI appears to be affected by filtering the data. This is expecially true for Korea than for state analyzed in U.S. In addition, it is found that the PDSI in the continental U.S. is more strongly correlated wiht ENSO than in Korea. Furthermore, in analyzing the El Nino and La Nina aggregate composite data, it is found that the dry anomalies in Korea occur from the year following El Nino to about tow years after while the wet anomalies occur from La Nina year for a period of about two years.

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Ancillary Service Requirement Assessment Indices for the Load Frequency Control in a Restructured Power System with Redox Flow Batteries

  • Chandrasekar, K.;Paramasivam, B.;Chidambaram, I.A.
    • Journal of Electrical Engineering and Technology
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    • v.11 no.6
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    • pp.1535-1547
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    • 2016
  • This paper proposes various design procedures for computing Power System Ancillary Service Requirement Assessment Indices (PSASRAI) for a Two-Area Thermal Reheat Interconnected Power System (TATRIPS) in a restructured environment. In an interconnected power system, a sudden load perturbation in any area causes the deviation of frequencies of all the areas and also in the tie-line powers. This has to be corrected to ensure the generation and distribution of electric power companies to ensure good quality. A simple Proportional and Integral (PI) controllers have wide usages in controlling the Load Frequency Control (LFC) problems. So the design of the PI controller gains for the restructured power system are obtained using Bacterial Foraging Optimization (BFO) algorithm. From the simulation results, the PSASRAI are calculated based on the settling time and peak over shoot concept of control input deviations of each area for different possible transactions. These Indices are useful for system operator to prepare the power system restoration plans. Moreover, the LFC loop coordinated with Redox Flow Batteries (RFB) has greatly improved the dynamic response and it reduces the control input requirements and to ensure improved PSASRAI, thereby improving the system reliability.

An Interactive Process Capability-Based Approach to Multi-Response Surface Optimization (대화식 절차를 활용한 공정능력지수 기반 다중반응표면 최적화)

  • Jeong, In-Jun
    • Journal of Korean Society for Quality Management
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    • v.45 no.2
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    • pp.191-207
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    • 2017
  • Purpose: To develop an interactive version of the conventional process capability-based approach, called 'Interactive Process Capability-Based Approach (IPCA)' in multi-response surface optimization to obtain a satisfactory compromise which incorporates a decision maker(DM)'s preference information precisely. Methods: The proposed IPCA consists of 4 steps. Step 1 is to obtain the estimated process capability indices and initialize the parameters. Step 2 is to maximize the overall process capability index. Step 3 is to evaluate the optimization results. If all the responses are satisfactory, the procedure stops with the most preferred compromise solution. Otherwise, it moves to Step 4. Step 4 is to adjust the preference parameters. The adjustment can be made in two modes: relaxation and tightening. The relaxation is to make the importance of one of the satisfactory responses lower, which is implemented by decreasing its weight. The tightening is to make the importance of one of the unsatisfactory responses higher, which is implemented by increasing its weight. Then, the procedure goes back to Step 2. If there is no response to be adjusted, it stops with the unsatisfactory compromise solution. Results: The proposed IPCA was illustrated through a multi-response surface problem, colloidal gas aphrons problem. The illustration shows that it can generate a satisfactory compromise through an interactive procedure which enables the DM to provide his or her preference information conveniently. Conclusion: The proposed IPCA has two major advantages. One is to obtain a satisfactory compromise which is faithful to the DM preference structure. The other is to make the DM's participation in the interactive procedure easier by using the process capability index in judging satisfaction/unsatisfaction. The process capability index is very familiar with quality practitioners as well as indicates the process performance levels numerically.

Increase in the Th1-Cell-Based Immune Response in Healthy Workers Exposed to Low-Dose Radiation - Immune System Status of Radiology Staff

  • Karimi, Gholamreza;Balali-Mood, Mahdi;Alamdaran, Seyed-Ali;Badie-Bostan, Hassan;Mohammadi, Elaheh;Ghorani-Azam, Adel;Sadeghi, Mahmood;Riahi-Zanjani, Bamdad
    • Journal of Pharmacopuncture
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    • v.20 no.2
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    • pp.107-111
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    • 2017
  • Objectives: Radiation is one of the most important sources of free radical (such as reactive oxygen species) production, which plays an essential role in the etiology of over hundred diseases. The aim of the study was to investigate some immune parameters and hematological indices in healthy workers of the Radiology Department, University Hospital of Mashhad, Iran. Methods: The study was performed on 50 healthy workers: 30 radiology staff as the case group and 20 laboratory workers as the control group. The radiation dose received by the radiology staff participating in the study was less than the annual maximum permissible level, 50 millisievert. Hematological parameters, lymphocyte proliferation and cytokine production were studied in both groups. Results: Among healthy radiology workers, the hematological indices did not differ statistically; however, their proliferation indices and $IFN-{\gamma}$ levels showed significant increases in parallel with decreases in the IL-4 levels as compared to controls. The immune system of workers exposed to low-dose ionizing radiation was found to be shifted from a Type 2 to a Type 1 response to promote cellular immunity. Conclusion: Based on our data, exposure to low-dose ionizing radiation may decrease the prevalence, frequency, and recurrence of various cancers and infectious diseases because of an increase in Th1-cell-based response, thus leading to more protection of the human body against tumor cells and foreign agents and possibly increased longevity. However, due to high rate of fluoroscopy use for interventional radiology, we suggest continuing research projects on radiation protection and hazards to prevent irreversible damage. As a recommendation, in future studies, radiology staff with a weakened immunity due to high radiation exposure should be considered as good choices to be treated using acupuncture techniques because acupuncture has been demonstrated to enhance the function and the number of immune cells.

Influence of Total Abdominal Fat Accumulation on Serum Lipids and Lipoproteins in Korean middle-aged men (한국 중년 남성에서 복부지방 축적이 혈청 지질 및 지단백 농도에 미치는 영향)

  • 허갑범;이종호;백인경;안광진;정윤석;김명중;이현철;이영해;이양자
    • Journal of Nutrition and Health
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    • v.26 no.3
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    • pp.299-312
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    • 1993
  • Anthropometry, computed tomography(CT) at the umbilical level, nutrient intake, blood pressure, serum levels of lipids and lipoproteins and response of glucose, c-peptide, insulin, and free fatty acid(FFA) during oral glucose tolerance test(OGTT) were estimated on 11 normal-weight controls and 35 overweight and obese middle-agd men. The areas of total abdominal, subcutaneous and visceral were determined by CT scanning technique. Total abdominal fat area correlated the most significantly with the levels of serum lipids, lipoproteins and insulin among several obese indices. Compared with normal-weight controls, overweight and obese men with abdominal fat lower than 29000$\textrm{mm}^2$ showed an increase in waist-hip ratio, areas of total abdominal(35%), visceral and subcutaneous fat and C-peptide response area during OGTT, though age, percent ideal body weight, body mass index, % body fat, and all biochemical indices except C-peptide response area were not different between two groups. Overweight and obese men with abdominal fat greater than 29000$\textrm{mm}^2$ showed a higher values in total abdominal fat(85%), serum levels of triglyceride, total-and LDL-cholesterol, the ratio of LDL-to HDL-cholesterol, and response areas of FFA, insulin and C-peptide during OGTT than normal-weight controls. Overweight and obese men with great abdominal fat showed an increase in alcohol ingestion and percent calorie intake per total energy expenditure, compared with normal-weight controls. Our results indicate that obesity and a certain level of total abdominal fat accumulation is required to observe abnormal levels of serum lipids, lipoproteins and insulin in Korean middle-aged men. In addition, increased alcohol and calorie intake and decreased physical activity could partly explain total abdominal fat accumulation in men.

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A Review Study on Ozone Phytotoxicity Metrics for Setting Critical Levels in Asia

  • Agathokleous, Evgenios;Kitao, Mitsutoshi;Kinose, Yoshiyuki
    • Asian Journal of Atmospheric Environment
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    • v.12 no.1
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    • pp.1-16
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    • 2018
  • Ground-level ozone ($O_3$) can be a menace for vegetation, especially in Asia where $O_3$ levels have been dramatically increased over the past decades. To ensure food security and maintain forest ecosystem services, such as nutrient cycling, carbon sequestration and functional diversity of soil biota, in the over-populated Asia, environmental standards are needed. To set proper standards, dose-response relationships should be established from which critical levels are derived. The predictor of the response in the dose-response relationship is an $O_3$ metric that indicates the dose level to which the plant has been exposed. This study aimed to review the relevant scientific literature and summarize the $O_3$ metrics used worldwide to provide insights for Asia. A variety of $O_3$ metrics have been used, for which we discuss their strengths and weaknesses. The most widely used metrics are based only on $O_3$ levels. Such metrics have been adopted by several regulatory agencies in the global. However, they are biologically irrelevant because they ignore the plant physiological capacity. Adopting AOT40 ($O_3$ mixing ratios Accumulated Over the Threshold of $40nmol\;mol^{-1}$) as the default index for setting critical levels in Asia would be a poor policy with severe consequences at national and Pan-Asian level. Asian studies should focus on flux-based $O_3$ metrics to provide relevant bases for developing proper standards. However, given the technical requirements in calculating flux-based $O_3$ metrics, which can be an important limitation in developing countries, no-threshold cumulative exposure indices like AOT0 should always accompany flux-based indices.