• Title/Summary/Keyword: second order effects

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Axial load detection in compressed steel beams using FBG-DSM sensors

  • Bonopera, Marco;Chang, Kuo-Chun;Chen, Chun-Chung;Lee, Zheng-Kuan;Tullini, Nerio
    • Smart Structures and Systems
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    • v.21 no.1
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    • pp.53-64
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    • 2018
  • Nondestructive testing methods are required to assess the condition of civil structures and formulate their maintenance programs. Axial force identification is required for several structural members of truss bridges, pipe racks, and space roof trusses. An accurate evaluation of in situ axial forces supports the safety assessment of the entire truss. A considerable redistribution of internal forces may indicate structural damage. In this paper, a novel compressive force identification method for prismatic members implemented using static deflections is applied to steel beams. The procedure uses the Euler-Bernoulli beam model and estimates the compressive load by using the measured displacement along the beam's length. Knowledge of flexural rigidity of the member under investigation is required. In this study, the deflected shape of a compressed steel beam is subjected to an additional vertical load that was short-term measured in several laboratory tests by using fiber Bragg grating-differential settlement measurement (FBG-DSM) sensors at specific cross sections along the beam's length. The accuracy of midspan deflections offered by the FBG-DSM sensors provided excellent force estimations. Compressive load detection accuracy can be improved if substantial second-order effects are induced in the tests. In conclusion, the proposed method can be successfully applied to steel beams with low slenderness under real conditions.

Retirement Preparing Behavior Analysis of Pastors with Application of Theory of Planned Behavior (계획된 행동이론을 적용한 목회자의 은퇴준비 행동분석)

  • Kim, Young-Chun;Kim, Jin-Youn
    • The Journal of the Korea Contents Association
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    • v.13 no.8
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    • pp.201-210
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    • 2013
  • The purpose of this study is to verify the effects on all factors from the research design by pastors. Research model is based on the theory of planned behavior. To this end, data were collected from 214 pastors and they were analyzed. In order to derived the results of a study, we used the statistical processing technique SPSS, to perform verification of factor analysis and reliability of each variable, AMOS analysis was performed for hypothesis testing. The results are as follows. First, this study demonstrated that there is a positive relationship between subjective norms and intention, perceived behavior control and intention of retirement preparing. Second, this study demonstrated that there is a positive relationship between intention and behavior, perceived behavior control and behavior of retirement preparing. Third, intention had a partial mediation effect between perceived behavior control and behavior of retirement preparing. As a result of this research, comprehensive implications were suggested for improving of retirement preparing by pastor.

The effects of Peer Relationship and Dysfunctional Family on Life Adjustment in University (대학생의 교우관계, 역기능 가정이 대학생활적응에 미치는 영향)

  • Jang, Sung-Hwa;Chun, Young-Hee;Ham, Seong-Soo
    • The Journal of the Korea Contents Association
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    • v.14 no.6
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    • pp.539-548
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    • 2014
  • The purpose of this study was to analyze the predictors of peer relationship and the dysfunctional family on life adjustment in university. The participants of study were 415 university students in Seoul province. A survey was carried out using convenient sampling, and correlation analysis and multiple regression were conducted. The results were summarized as follows: First, as for the peer relationship, dysfunctional family and life adjustment in university, all of the subvariables except for conflict, distrust and university of adaptation show significant correlations. Second, a multiple regression analysis showed that, in order of significance, conflict resolution, problem parents, recognition and attention variables significantly affected life adjustment in university. This has implications for the prevention of misfit university students, the related program development, and various policy establishments.

The Contractile and Electrical Responses of Guinea-pig's Gastric Smooth Muscle to Serotonin

  • Lee, Sang-Jin;Hwang, Sang-Ik;Kim, Ki-Whan
    • The Korean Journal of Physiology
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    • v.25 no.2
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    • pp.133-146
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    • 1991
  • In order to elucidate systematically the effects of serotonin on gastric motility of guinea-pig, the contractile and electrical responses to serotonin were recorded using four kinds of muscle strips prepared from antral circular, antral longitudinal, fundic circular, and fundic longitudinal muscles. Experiments were performed using various methods including isometric contraction recording, transmural electrical field stimulation, junction potential recording, intracellular microelectrode technique, and partition stimulation method. The results were as follows: 1) The effect of serotonin on spontaneous contractions was inhibitory in the circular muscle strips of the antrum and fundus, while it was excitatory in the longitudinal muscle strips of the antrum and fundus. Serotonin changed mainly phasic contractions of both the circular and longitudinal muscle strips in the antrum, while it changed mainly tonic contractions of both the circular and longitudinal muscle strips in the fundus. 2) On the contractions induced by transmural nerve stimulation, serotonin decreased the amplitude in the circular muscle strips of the antrum, but it increased them in the other three groups of muscle strips(antral longitudinal, fundic circular, and fundic longitudinal). 3) On the contractions induced by direct muscle stimulation, serotonin decreased the amplitude in the circular muscle strips of the antrum and fundus. 4) In the fundic circular muscle strips serotonin potentiated excitatory junction potentials (EJPs), and in the antral circular muscle strips it evoked EJPs after inhibitory junction potentials(IJPS). 5) In the antral circular muscle strips serotonin did not affect the slow wave even at the disappearance of spontaneous contractions. On the contrary it increased the amplitude of the slow wave, when the spike component was potentiated and the second component was inhibited. 6) In the antral circular muscle strips the membrane potential was slightly hyperpolarized, but the membrane resistance was not changed. From the above results following conclusions could be made. 1) Serotonin inhibits spontaneous contractions of the circular muscle layer and it increases those of the longitudinal one, irrespective of the gastric region. 2) In the guinea-pig stomach there exists a serotoninergic facilitatory neuromodulation system which exerts its effect on cholinergically mediated contraction. 3) The excitation-contraction decoupling was observed in the effect of serotonin.

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The Effects of Internal Polity on Commitment and Relationship Performance between Franchisors and Franchisees (프랜차이즈 본부와 가맹점간의 내부정치가 결속 및 관계성과에 미치는 영향)

  • Cho, Hyun-Jin
    • Journal of Distribution Research
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    • v.10 no.2
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    • pp.27-47
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    • 2005
  • This study is basically focused on the relationship between the franchisors and franchisees. The goal of this study is mainly to inquire the variables of relationship characteristics affecting the commitment which lies in internal polity, and secondly to comprehensively analyze the performance resulting from commitment and examine the efficient alternatives onto relationship management. The practical methodology using in this study has been done in a national representing food franchise system. This study has been resulted in following: First, the variables that show significantly to the commitment are noncoercive influential strategy, dependence, cooperation, and goal divergence. In the contrast the coercive influential strategy hasn't showed significantly; Second, the result has showed that the commitment when it would be related with performance furthered the financial performance and role performance; and. therefore, we finally conclude that it would be more important to make lots of efforts of establishing the win-win relationship through the long-term commitment between the franchisor and franchisee in order to develop the more effective relationship of the franchise system.

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Effect of Dietary Fatty Acids and Vitamin E Supplementation on Antioxidant Vitamin Status of the Second Generation Rat Brain Sections (식이 지방산 및 비타민 E 보충 식이가 흰쥐의 뇌조직 부위별 항산화 비타민 농도에 미치는 영향)

  • 박정화;황혜진;김미경;이양자
    • Journal of Nutrition and Health
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    • v.34 no.7
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    • pp.754-761
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    • 2001
  • Effects of dietary fatty acids and vitamin E on antioxidant vitamin status were studied in rat brain sections. Sources of dietary fat(10t%) were safflower oil(SO) poor in $\omega$3 fatty acid and mixed oil (MO) with computer-adjustd fatty acid ratios(AA/DHA=1.4, $\omega$6/$\omega$3=6.3, P/M/S=1.0/1.5/1, AA=2.%)with (ME) and without(MO) vitamin E(500mg/kg diet). Rats were fed the three kinds of diet from 3-4 wks prior to the conception. At the age of 3 & 9wks of the 2nd generation rat, antioxidant vitamins were measured in frontal cortex(FC), corpus striatum (CS), cerebellum(CB) and hippocampus(HP) using a multiwavelength, reverse phase gradient HPLC system. The levels of antioxidant vitamins converged to the similar value in all groups at 9 wks of age. Retinol, lycopene and cryptoxanthin levels of all experimental groups were found to be the highest in hippocampus at both 3 & 9wks of age. The levels of vitamin E appeared to be higher in the order of HP>CS-CB>FC in MO & ME. Beta-carotene and retinol showed the lowest level in hippocampus of vitamin E supplemented groups, even though vitamin E level tended to be higher in other sections. It seemed that vitamin E has an inhibitory action on the uptake of beta-carotene or acts as a preferred antioxidant to beta-carotene in certain section of the brain. By improving fatty acid balance (AA/DHA = 1.4, $\omega$6/$\omega$3=6.3, P/M/S=1.0/1.5/1, AA = 2%), the levels of vitamin E, retinol, lycopene & beta=carotene tended to be higher in MO than in SO, although crytoxanthin became lower at 3wks of age. In short, dietary fatty acids and vitamin E have different influence on antioxidant vitamin status in different rat brain sections. The higher levels of antioxidant vitamins in hippocampus should be pursued further in relation to behavioral development of rats.

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STUDIES ON THE SHELLFISH PROCESSING 6. Effect of Antioxidants or EDTA Treatment on the Quality of Pressed-and-Dehydrated Sea Mussel Mytilus edulis (패류 가공에 관한 연구 6. 항산화제 또는 EDTA 처리가 진주담치 압착 건제품의 제조 및 저장중의 품질에 미치는 영향에 대하여)

  • HUR Jong-Wha;LEE Eung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.4 no.1
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    • pp.22-30
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    • 1971
  • Sea mussel Mytilus edulis, world-widely distributed, is a sort of popular food in Korea. The demands of high quality and mass production are not being satisfied since it is usually sun dried. A rapid dehydration and the treatment of food additives to improve the quality of the product seems to be required. In this paper, the effect of antioxidants and EDTA treatment was studied when sea mussel was pressed and hot-air dehydrated for 10 hours at 45 to $52^{\circ}C$ under the air flow rate of 3 meter per second. The results are as follows: 1) Cooked and pressed sea mussel was dehydrated mere rapidly than cooked without pressing. 2) The rehydration rate of pressed and dehydrated sea mussel was higher than that of the unpressed. 3) Among six samples, BHA treated material showed the best color preservation during dehydration and storage. The treatment of Teonox-II was also effective following BHA. 4) The effects of antioxidants used during dehydration and storage were in order of BHA, Tenox-II and NDGA treatment, while EDTA was ineffective. 5) No significant difference in rehydration rate was found between those treated with antioxidants or EDTA and the untreated. 6) The amount of soluble protein was higher in the samples treated with antioxidants than in EDTA treated or untreated samples. 7) The results suggest that the treatment of BHA and pressing process produce improved product in quality which gives higher amount of soluble protein and better rehydration, color preservation and preventive effect of rancidity.

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Application of Response Surface Method as an Experimental Design to Optimize Coagulation Tests

  • Trinh, Thuy Khanh;Kang, Lim-Seok
    • Environmental Engineering Research
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    • v.15 no.2
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    • pp.63-70
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    • 2010
  • In this study, the response surface method and experimental design were applied as an alternative to conventional methods for the optimization of coagulation tests. A central composite design, with 4 axial points, 4 factorial points and 5 replicates at the center point were used to build a model for predicting and optimizing the coagulation process. Mathematical model equations were derived by computer simulation programming with a least squares method using the Minitab 15 software. In these equations, the removal efficiencies of turbidity and total organic carbon (TOC) were expressed as second-order functions of two factors, such as alum dose and coagulation pH. Statistical checks (ANOVA table, $R^2$ and $R^2_{adj}$ value, model lack of fit test, and p value) indicated that the model was adequate for representing the experimental data. The p values showed that the quadratic effects of alum dose and coagulation pH were highly significant. In other words, these two factors had an important impact on the turbidity and TOC of treated water. To gain a better understanding of the two variables for optimal coagulation performance, the model was presented as both 3-D response surface and 2-D contour graphs. As a compromise for the simultaneously removal of maximum amounts of 92.5% turbidity and 39.5% TOC, the optimum conditions were found with 44 mg/L alum at pH 7.6. The predicted response from the model showed close agreement with the experimental data ($R^2$ values of 90.63% and 91.43% for turbidity removal and TOC removal, respectively), which demonstrates the effectiveness of this approach in achieving good predictions, while minimizing the number of experiments required.

Study on corporate Culture & Job Satisfaction of Airlines' Flight Attendants (항공사 객실 승무원의 조직문화와 직무만족에 관한 연구)

  • Heo, Myung-Sun;Yoon, Sun-Yung
    • Journal of Advanced Navigation Technology
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    • v.13 no.1
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    • pp.1-10
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    • 2009
  • In this study, what effects corporate culture of airlines' flight attendants has on job satisfaction was analyzed and the following results were derived. First, it showed that flight attendants of airlines feel job satisfaction with the ability of handling works by themselves before supervisors order something, with the faith of supervisors that subordinates will be able to work well, and with being able to talk about difficulties of the company open-minded. Second, flight attendants inairlines showed different levels of recognition about corporate culture based on age, married or not, position and how long they have worked in the company. Especially, it showed a big difference by their positions. Third, looking into the effect demographical characters have on job satisfaction, it indicated that the higher the positions were, the higher job satisfaction was, and especially, compared that job satisfaction of flight attendants having 4-7 years' careers is low, that of the flight attendantsmore than 8 years is high.

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The Buffering Effect of Family Cohesion in the Relationship between Depression and Suicidal Risk (우울감과 자살위험간의 관계에서 가족결속도의 완충효과)

  • Kim, Yun-Jeong;Kang, Hyun-Jung
    • The Journal of the Korea Contents Association
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    • v.14 no.3
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    • pp.241-249
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    • 2014
  • The aim of this paper is to examine the buffering effect of family cohesion in the relationship between depression and suicidal risk among adolescents, adults, and the elderly. To achieve the research aim, surveys were conducted in 10 cities across the country for 399 adolescents, 473 adults, and 370 elderly from May to August 2010. Major findings of the data analysis are as follows. First, while, in the relationship between depression and suicidal risk, the elderly were the highest, followed by adolescents and adults in descending order, in family cohesion, adults were the highest, followed by the elderly and adolescents. Second, the analysis of the buffering effect of family cohesion in the relationship between depression and suicidal risk showed that it was significant only for adolescents and adults, which means that for those two groups family cohesion alleviates the effects of depression on suicidal risk, demonstrating the necessity of strengthening family cohesion to reduce suicides among the two groups of people. But, for the elderly for whom family relationship is more important than any other age group, the buffering effect of family cohesion in the relationship between depression and suicidal risk was not proved. The interpretation of this phenomenon is given in the part of the paper where the characteristics of the suicide of the old age group is discussed.