• Journal of the Korea Concrete Institute
• /
• v.19 no.1
• /
• pp.121-130
• /
• 2007

To investigate the enhancement in strength and deformation capacities of concrete confined by FRP composites, tests under axial loads were carried out on three groups of thirty six short columns in circular section with diverse GFRP confining reinforcement. The major test variables considered include fiber content or orientation, wrap or tube type by varying the end loading condition, and continuous or discontinuous confinement depending on the presence of vortical spices between its two halves. The circumferential FRP strains at failure for different types of confinements were also investigated with emphasis. Various analytical models capable of predicting the ultimate strength and strain of the confined concrete were examined by comparing to observed results. Tests results showed that FRP wraps or tubes provide the substantial increase in strength and deformation, while partial wraps comprising the vertical discontinuities fail in an explosive manner with less increase in strength, particularly in deformation. A bilinear stress-strain response was observed throughout all tests with some variations of strain hardening. The failure hoop strains measured on the FRP surface were less than those obtained from the tensile coupons in all tests with a high degree of variation. In overall, existing predictive equations overestimated ultimate strengths and strains observed in present tests, with a much larger scatter related to the latter. For more accuracy, two simple design- oriented equations correlated with present tests are proposed. The strength equation was derived using the Mohr-Coulomb failure criterion, whereas the strain equation was based on entirely fitting of test data including the unconfined concrete strength as one of governing factors.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.31 no.3A
• /
• pp.235-249
• /
• 2011

A new form of I-type PSC bridge girder, which has hole in the web, is proposed in this paper. Three different concepts were combined and implemented in the design. First of all, a girder was precast at a manufacturing plant as divided pieces and assembled at the construction site using post-tensioning method, and the construction period at the site will be reduced dramatically. In this way, the quality of concrete can be assured at the manufacturing factory and concrete curing can be well controlled, and the spliced girder segments can be moved to the construction site without a transportation problem. Secondly, a numerous number of holes was made in the web of the girder. This reduces the self-weight of the girder. But more important thing related to the holes is that about half of the total anchorages can be moved from the girder ends into individual holes. The magnitude of negative moment developed at girder ends will be reduced. Also, since the longitudinal compressive stresses are reduced at ends, thick end diaphragm is not necessary. Thirdly, Prestressing force was introduced into the member through multiple stages. This concept of multi-stage prestressing method overcomes the prestressing force limit restrained by the allowable stresses at each loading stage, and maximizes the magnitude of applicable prestressing force. It makes the girder longer and shallower. Two 50 meter long full scale girders were fabricated and tested. One of them was non-spliced, or monolithic girder, made as one piece from the beginning, and the other one was assembled using post-tensioning method from five pieces of segments. It was found from the result that monolithic and spliced girder show similar load-deflection relationships and crack patterns. Girders satisfied specific girder design specification in flexural strength, deflection, and live load deflection control limit. Both spliced and monolithic holed web post-tensioned girders can be used to achieve span lengths of more than 50m with the girder height of 2 m.

• Journal of Periodontal and Implant Science
• /
• v.36 no.2
• /
• pp.555-565
• /
• 2006

The purpose of the present study is to evaluate the biological stability of the zirconia/alumina composite abutment by histologic and radiographic examination in clinical cases. 17 partially edentulous patients (5 men and 12 women, mean age 47) were treated with 37 implants. The implants were placed following the standard two-stage protocol. After a healing period of 3 to 6 months, zirconia/alumina composite abutments were connected. All radiographs were taken using paralleling technique with individually fabricated impression bite block, following insertion of the prosthesis and at the 3-, 6-, 12 month re-examinations. After processing the obtained images, the osseous level was calculated using the digital image in the mesial and distal aspect in each implant. An ANOVA and t-test were used to test for difference between the baseline and 3-, 6-, 12 months re-examinations, and for difference between maxilla and mandible. Differences at P <0.05 were considered statistically significant. For histologic examination, sample was obtained from the palatal gingiva which implant functioned for 12 months. Sections were examined under a light microscope under various magnifications. Clinically, no abutment fracture or crack as well as periimplantitis was observed during the period of study. The mean bone level reduction(${\pm}standard$ deviation) was 0.34 rom(${\pm}\;0.26$) at 3-months, 0.4 2mm(${\pm}\;0.30$) at 6-months, 0.62 mm(${\pm}\;0.28$) at 12-months respectively. No statistically significant difference was found between baseline and 3-, 6-, 12-months re-examinations (p > 0.05). The mean bone level reduction in maxilla was 0.33(${\pm}0.25$) at 3-months, 0.36(${\pm}0.33$) at 6-months, 0.56(${\pm}0.26$) at 12-months. And the mean bone level reduction in mandible was 0.35(${\pm}0.27$) at 3-months, 0,49(${\pm}0.27$) at 6-months, 0.68(${\pm}0.30$) at 12-months. No statistical difference in bone level reduction between implants placed in the maxilla and mandible. Histologically, the height of the junctional epithelium was about 2.09 mm. And the width was about 0.51 mm. Scattered fibroblasts and inflammatory cells, and dense collagen network with few vascular structures characterized the portion of connective tissue. The inflammatory cell infiltration was observed just beneath the apical end of junctional epithelium and the area of direct in contact with zirconia/alumina abutment. These results suggest the zirconia/alumina composite abutment can be used in variable intraoral condition, in posterior segment as well as anterior segment without adverse effects.

• Journal of Chest Surgery
• /
• v.32 no.9
• /
• pp.773-780
• /
• 1999

Background: It has been demonstrated that brief periods of calcium depletion and repletion (calcium-free preconditioning, CP) have cardioprotective effects as seen in ischemic preconditioning(IP) which enhances the recovery of post-ischemic contractile dysfunction and reduces the incidence of reperfusion-induced arrhythmia or infarct size after a prolonged ischemia. In the present study, we tested this paradoxical phenomenon in isolated rabbit hearts. Material and Method: Hearts isolated from New Zealand white rabbits(1.5∼2.0 Kg body weight) were perfused with Tyrode solution using the Langendorff technique. After stabilizing the baseline hemodynamics, the hearts were subjected to 45 minutes of global ischemia followed by 120 minutes of reperfusion with IP(IP group, n=7) or without IP (ischemic control group, n=7). IP was induced by a single episode of 5 minutes global ischemia and 10 minutes reperfusion. In the CP group(n=7), the hearts were subjected to perfusion with Tyrode solution with calcium depletion for 5 minutes and repletion for 10 minutes, and 45 minutes of ischemia and 120 minutes of reperfusion. Left ventricular function including developed pressure, dP/dt, heart rate, left ventricular end-diastolic pressure and coronary flow was measured. Infarct size was determined by staining with 1% triphenyltetrazolium chloride and planimetry. Data were analyzed by a one-way analysis of variance and Tukey's post-hoc test. Result: In comparison with the ischemic control group, IP significantly enhanced the recovery of the left ventricular function including the left ventricular developed pressure, contractility, and coronary flow; in contrast, these functional parameters of the CP group tended to be lower than those of the ischemic control group. However, the infarct size was significantly reduced by IP or CP(p<0.05). Conclusion: These results suggest that in isolated Langendorff-perfused rabbit heart model, CP(induced by single episode of 5 minutes calcium depletion and 10 minutes repletion) could not improve the post-ischemic contractile dysfunction(after a 45-minute global ischemia) but it has an infarct size-limiting effect.

• Korean journal of food and cookery science
• /
• v.21 no.5
• /
• pp.677-684
• /
• 2005

This study investigated the changes in physicochemical characteristics after 120 days of aging Korean red pepper paste, 'Kochujang', made of minor cereals in substitution for glutinous rice which has been conventionally used as starch source. The cereals used were waxy job's tears, proso millet, sorghum, barley and foxtail millet, Glutinous rice with barley was used as controls. The items determined were water activity, pH, content of amino nitrogen, chromaticity and sensory test. 1. The water activities(Aw) of Kochujang samples were in range of $0.72{\sim}0.82$ at the beginning of fermentation, with Aw barley paste bing the lowest, and Aw of sorghum paste bing the highest. Then Aw were slowly decreased to the range of $0.49{\sim}0.50$ during 120 days of fermentation 2. The pH of the pastes was in range of $4.94{\sim}5.02$ at the initial time of fermentation, and decreased steadily to 4.32{\sim}4.73 at the end. 3. The content of amino nitrogen was in range of $330.9{\sim}340.7\;mg%$ at the early time of fermentation. The highest content, $351{\sim}381\;mg%$, was observed at the 90th day of aging of glutinous rice paste, 105th day of job's tears paste, 75th day each of barley and proso millet, and 60th day each of sorghum and foxtail millet. 4. The Hunter tristimulus values (L, a, b) of all pastes were gradually decreased during fermentation. The value of barley paste was lowest among the pastes. 5. The texture of barley paste in sensory test showed significant difference with other pastes, whereas there were no differences in color, odor, taste and sensory qualities.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.15 no.2
• /
• pp.124-134
• /
• 2005

To investigate the exposure effect of polynuclear aromatic hydrocarbons (PAHs), we measured airborne total PAHs as an external dose, urinary 1-hydroxypyrene (1-OHP) as an internal dose of PAHs exposure, and analyzed the relationship between urinary 1-OHP concentration and PAHs exposure. The study population contained 44 workers in steel-pipe coating and paint manufacture industries. The airborne PAHs was obtained during survey day, and urine were sampled at the end of shift. Personal information on age, body weight, height, eniployment duration, smoking habit, and alcohol consumption was obtained by a structured questionnaire. Airborne PAHs were analyzed by the gas chromatograph with mass selective detector. Urinary 1-OHP levels were analyzed by the high performance liquid chromatograph with ultraviolet wavelength detector. For statistical estimation, t-test, ${\chi}^2$-test, analysis of variance, correlation analysis, arid regression analysis were executed by SPSS/PC (Windows version 10). The mean of environmental total PAHs was $87.8{\pm}7.81{\mu}g/m^3$. The mean concentration ($526.5{\pm}2.85{\mu}g/m^3$) of workers in steel-pipe coating industries using coal tar enamel was the higher than that ($17.5{\pm}3.36{\mu}g/m^3$) of workers in paint manufacture industries using coal tar paint. The mean of urinary 1-OHP concentration ($51.63{\pm}3.144{\mu}\;mol/mol$ creatinine) of workers in steel-pipe coating industries was the higher than that ($2.33{\pm}4.709{\mu}\;mol/mol$ creatinine) of workers in paint manufacture industries. The mean of urinary 1-OHP concentration of smokers was the higher than that of non-smokers. There was significant correlation between the urinary concentration of 1-OHP and the environmental concentration of PAHs (r=O.S48, p<0.001), pyrene(r=0.859, p<0.001), and urinary cotinine (r=0.324, p<0.05). The regression equation between the urinary concentration of 1-OHP in ${\mu}g/g$ creatinine($C_{1-OHP}$) and airborne concentration of PAHs (or pyrene) in ${\mu}g/m^3$ ($C_{PAHs}$ or Cpyrene) is: Log ($C_{1-OHP}$)=-0.650+0.889×Log($C_{PAHs}$), where $R^2=0.694$ and n=38 for p<0.001.Log ($C_{1-OHP}$)=1.087+0.707${\times}$Log(Cpyrene), where $R^2=0.713$ and n=38 for p<0.001. From the results of stepwise multiple regression analysis about 1-OHP, significant independents were total PAHs and urinary cotinine (adjusted $R^2=0.743$, p<0.001). In this study, there were significant correlation between the urinary concentration of 1-OHP and the airborne concentration of PAHs. The urinary 1-OHP was effective index as a biomarker of airborne PAHs in workplace. But it was influenced by non-occupational PAHs source, smoking.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.11
• /
• pp.7524-7533
• /
• 2015

The purpose of this study was to investigate the effects of purple sweet potato(PSP) intake and aerobic combined exercise in obese middle school girls. Twenty-four, obese(%body fat > 30%) middle school girls composed of the purple sweet potato intake and aerobic combined exercise group(A, n=6), the aerobic combined exercise group(B, n=6), the purple sweet potato intake group(C, n=6), the control group(D, n=6). The variables of health related fitness, blood lipid profile, insulin resistance were measured in all the subjects before the start and after the end of 12 week aerobic combined exercise program(40~70%HRR, 3 times per week, 70 mins). The test data were analyzed by paired t-test and one way ANOVA, and the alpha level of p<.05 was set for all tests of significance. In the comparison within each group, %body fat[A(p<.01), C(p<.05) groups], TC[A(p<.05), B(p<.01), C(p<.01) groups] and insulin resistance[A(p<.05) group] were significantly decreased and LBM[A(p<.01), B(p<.01) groups], muscular strength[A(p<.01), B(p<.001), C(p<.05) groups], muscular endurance[A(p<.05), B(p<.001) groups], flexibility[A(p<.05), B(p<.01) groups] and cardiorespiratory endurance[A(p<.05), B(p<.001), C(p<.01) groups] were significantly increased. In the comparison between groups, A group was significantly decreased in %body fat, TC and TG than D group(p<.05). A group was significantly increased in muscular strength and cardiorespiratory endurance than C, D groups (p<.05). A group was significantly increased in muscular endurance and HDL-C than D group(p<.05). A, B groups were significantly increased in flexibility than D group(p<.05). A, B, C groups were significantly decreased in insulin resistance than D group(p<.05). In conclusion, purple sweet potato intake and aerobic combined exercise were effective in improving the health related fitness, blood lipid profile and insulin resistance in obese middle school girls.

• Korean Journal of Hospice Care
• /
• v.2 no.2
• /
• pp.28-48
• /
• 2002

The advances of medical technologies have not only prolonged human life span, but also extended suffering period for the patients with incurable medical diseases. Hospice movement was developed to help these patients keep dignity and lives peaceful at the end of their life. Since many patients prefer to spend the last moment of life at home with their family, hospice home care has become very popular worldwide. The purpose of this study for a promotion and development of hospice home care in Korea, and features basic research on medical profession's knowledge and attitudes to hospice home care. This study which was used for the research questionnaires developed by the researcher that were answered by 100 physicians and 127 nurses in a general hospital. Data were collected from April 22, 2002 to May 10, 2002. The SPSS was used to make a comparative analysis of the frequency, percentile, ANOVA, and x2-test. The results of the study were as follows; 1.The medical profession showed high level of knowledge of the definition and philosophy of hospice. However, the physician group of the examinees showed insufficient knowledge of the fact that hospice care includes bereavement care, while the nurse group's response to the same question showed a significant difference(x2=10.752, p=.001). 2.For whom the hospice home care is provided, 95.6% of the respondents showed very high level of knowledge as answering that the incurable terminal illness patients and their families are the beneficiaries of hospice care. The respondents counted nurses, volunteers, pastors, physicians and social workers, consecutively, as hospice care providers. More nurse were positive toward pastors than physicians in regarding as a hospice care provider by a significant difference(x2=11.634, p=.001). 3.For when to referral hospice home care to the patients, only 34.2% answered that patients with less than 6 months of survival time are advised to receive hospice care, reflecting very low level of knowledge. 23.0% of the physicians and 48.0% of the nurses answered that hospice care should be provided when death is imminent, making a significant difference between the two groups(x2=6.413, p=.000). 4.To promote hospice activities, 87.2% pointed out that it is crucial to make general people, including those engaging in the medical field, more aware of hospice. 79.7% answered that a national hospice management should be developed, marking a significant difference between the physician group and nurse group(x2=10.485, p=.001). 5.Advantages of hospice home care are 87.2% responded that patients can have better rest at home receiving hospice home care. Economical merit was brought forward as one of the advantages also, where there was a significant difference between the physicians group and nurse group(x2=7.009, p=.008). 6.The medical professions' attitude to hospice home care are 92.8% of the physicians answered that they would advise incurable terminally ill patients to be discharged from hospital, with 44.3% of them advising the patients to receive hospice home care after leaving the hospital. From the nurses' point of view, 20.9% of the terminally ill patients are being referred to hospice home care after discharge, which makes a significant difference from the physicians' response(x2=19.121, p=.001). 7. 30.6% of physicians have referred terminally ill patients to hospice home care, 75.9% of whom were satisfied with their decision. Those physicians who have never referred their patients to hospice home care either did not know how to do it(66.7%) or were afraid of losing trust by giving the patients an impression of giving up(27.3%). 94.9% of the physicians responded that they would refer their last stage patients to a doctor who is involving palliative care. 8.Only 36.2% of nurses have suggested to physicians that refer the terminally ill patients discharged from the hospital to hospice home care. Once suggested, 95.8% of the physicians have accepted the suggestion. Nurses were reluctant to suggest hospice home care to the physicians, as 48.8% of the nurses said they did not want to. From the result of this study the following conclusion can be drawn, the medical profession's awareness of general hospice care has been increased greatly compared to the results of the previously performed studies. However, this study result also shows that their knowledge of hospice home care is not good enough yet. There is a need for high recommended that medical education institute and develop regular courses on various types of hospice care. Medical field training courses for physicians and nurses will be very helpful as well. It is also important to train hospice experts such as palliative physicians and develop a national hospice management urgently in order to improve the hospice care in Korea.

• Journal of Global Scholars of Marketing Science
• /
• v.20 no.3
• /
• pp.249-261
• /
• 2010

As consumers' concern for the environment has continued to increase, many firms have actively engaged in environmental marketing to achieve their objectives. However, consumers' high concerns about the environment are not always reflected in their purchasing behavior. This indicates the need for an in-depth understanding of the development of green consumption within the individual's belief system. In consideration of psychological approaches, a large body of research has examined the factors underlying ecologically conscious "green" consumer behavior and the interrelationships of these factors. However, most previous studies have concentrated on Western countries. Using a sample of Korean consumers, this study attempts to understand the basis of Korean green consumerism and find universal values that are cross-culturally important in guiding consumers' environmental attitudes and behaviors. To this end, this study relates Schwartz's 10 universal values (Schwartz 1992) to environmental behaviors in a hierarchical model of value-attitude-behavior. With reference to the value-attitude-behavior framework, the conceptual model developed for the study explains what motivations can be manifested in Korean consumers' environmental attitudes, and subsequently how the attitudes affect their green choices. Using the pattern of relationships among values that can be related to environmentalism, the first hypothesis holds that there would be particular relationships between motivational value types and environmental attitudes. Hypothesis 2 assumes that environmental attitudes predict environmental behaviors. On the basis of the claim that favorable attitudes toward the environment may be expressed in many different behaviors, the assumption is that consumers' favorable attitudes toward the environment would be linked to a variety of environmental behaviors because people with high environmental attitudes can be more interested in and knowledgeable about environmental actions. Consistent with H2, H3 hypothesizes that there would be a positive relationship between different types of environmental behavior. A total of 564 university students participated in the study. The sample included 308 men, 254 women, and two participants who did not indicate their gender. The average age of the participants was 22.5 years, with a range of 19 to 39. Regarding majors, special efforts were made to draw the participants from different departments of the university. Data were collected by a survey administered via self-completion questionnaires., which assessed the participants' value priorities, environmental attitudes, and behaviors. Path analysis conducted to test the proposed model found the overall fit to be ${\chi}^2$=72.01 (p=0.00), GFI=0.983, CFI=0.982, NFI=0.970, RMR=0.070, and REMSEA=0.050. Thus, most of the fit measures indicated a good fit of the model with the data, and a hierarchical relationship from values to environmental attitudes to environmental non-purchasing behavior to environmental purchasing behavior was confirmed. An assessment of all the predicted paths by path coefficients led to several major hypothesized effects being confirmed. Out of the ten value types, universalism and power were significantly but conversely related to environmental attitudes. In line with the other studies, these findings confirm that environmental attitudes are an important factor in leading to a variety of green behaviors. Finally, significant relationships were found between environmental purchasing and non-purchasing behaviors. The path analysis supported the idea that universalism values provide a motivation for Korean consumers' greenness and indirectly promote environmental acts through favorable attitudes toward the environment. Participants with high environmental attitudes were found to actively engage in diverse forms of green consumer behavior. This research provides an opportunity to examine cross-cultural differences with respect to values leading to environmentalism, and, further, to verify previous findings. The study also examined the attitude-behavior relationship with respect to three distinct types of environmental behaviors. The different strengths of paths between green attitudes and behaviors suggest that researchers should consider the specificity of behavior explained as an effort to improve the low attitude-behavior correlation. Finally, the findings here illustrate that with increased environmental concerns among people, they come to include more such behaviors in their green portfolios.

• Journal of Intelligence and Information Systems
• /
• v.17 no.1
• /
• pp.91-110
• /
• 2011

This paper analyzes the cases where the hotels have increased their services and enhanced their work process through IT solutions to cope with computerization globalization. Also the cases have been studies where national hotels use the CRM solution internally to respond effectively to customers requests, increase customer analysis, and build marketing strategies. In particular, this study discusses the introduction of the CRM solutions and CRM sales business and marketing services using a process for utilizing the presumed, CRM by introducing effective DEA(Data Envelopment Analysis). First, the comparison has done regarding the relative efficiency of L Company with the CCR model, then compared L Company's restaurants and facilities' effectiveness through BCC model. L Company reached a conclusion that it is important to precisely create and manage sales data which are the preliminary data for CRM, and for that reason it made it possible to save sales data generated by POS system on each sales performance database. In order to do that, it newly established Oracle POS system and LORIS POS system concerned with restaurants for food and beverage as well as rooms, and made it possible to stably generate and manage sales data and manage. Moreover, it set up a composite database to control comprehensively the results of work processes during a specific period by collecting customer registration information and made it possible to systematically control the information on sales performances. By establishing a system which unifies database and managing it comprehensively, impeccability of data has been greatly enhanced and a problem which generated asymmetric data could be thoroughly solved. Using data accumulated on the comprehensive database, sales data can be analyzed, categorized, classified through data mining engine imbedded in Polaris CRM and the results can be organized on data mart to provide them in the form of CRM application data. By transforming original sales data into forms which are easy to handle and saving them on data mart separately, it enabled acquiring well-organized data with ease when engaging in various marketing operations, holding a morning meeting and working on decision-making. By using summarized data at data mart, it was possible to process marketing operations such as telemarketing, direct mailing, internet marketing service and service product developments for perceived customers; moreover, information on customer perceptions which is one of CRM's end-products could feed back into the comprehensive database. This research was undertaken to find out how effectively CRM has been employed by comparing and analyzing the management performance of each enterprise site and store after introducing CRM to Hotel enterprises using DEA technique. According to the research results, efficiency evaluation for each site was calculated through input and output factors to find out comparative CRM system usage efficiency of L's Company four sites; moreover, with regard to stores, the sizes of workforce and budget application show a huge difference and so does the each store efficiency. Furthermore, by using the DEA technique, it could assess which sites have comparatively high efficiency and which don't by comparing and evaluating hotel enterprises IT project outcomes such as CRM introduction using the CCR model for each site of the related enterprises. By using the BCC model, it could comparatively evaluate the outcome of CRM usage at each store of A site, which is representative of L Company, and as a result, it could figure out which stores maintain high efficiency in using CRM and which don't. It analyzed the cases of CRM introduction at L Company, which is a hotel enterprise, and precisely evaluated them through DEA. L Company analyzed the customer analysis system by introducing CRM and achieved to provide customers identified through client analysis data with one to one tailored services. Moreover, it could come up with a plan to differentiate the service for customers who revisit by assessing customer discernment rate. As tasks to be solved in the future, it is required to do research on the process analysis which can lead to a specific outcome such as increased sales volumes by carrying on test marketing, target marketing using CRM. Furthermore, it is also necessary to do research on efficiency evaluation in accordance with linkages between other IT solutions such as ERP and CRM system.