• Composites Research
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• v.17 no.4
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• pp.7-17
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• 2004

In this study, the effect of laminate thickness on the compressive behaviour of composite materials is investigated through systematic experimental work using the stacking sequences, $[O_4]_{ns},{\;}[45/0/-45/90]_{ns}$ and $[45_n/0_n/-45_n/90_n]_s$ (n=2 to 8). Parameters such as fibre volume fraction, void content, fibre waviness and interlaminar stresses, influencing compressive strength with increasing laminate thickness are also studied experimentally and theoretically. Furthermore the stacking sequence effects on failure strength of multidirectional laminates are examined. For this purpose, two different scaling techniques are used; (1) ply-level technique $[45_n/0_n/-45_n/90_n]s$ and (2) sublaminate level technique $[45/0/-45/90]_{ns}$. An apparent thickness effect existes in the lay-up with blocked plies, i.e. unidirectional specimens ($[O_4]_{ns}) and ply-level scaled multidirectional specimens ($[45_n/0_n/-45_n/90_n]_s$). Fibre waviness and void content are found to be main parameters contributing to the thickness effect on the compressive failure strength. However, the compressive strength of the sublaminate level scaled specimens ($[45/0/-45/90]_{ns}$) is almost unaffected regardless of the specimen thickness (since ply thickness remains constant). From the investigation of the stacking sequence effect, the strength values obtained from the sublaminate level scaled specimens are slightly higher than those obtained from the ply level scaled specimens. The reason for this effect is explained by the fibre waviness, void content, free edge effect and stress redistribution in blocked $0^{\circ}$ plies and unblocked $0^{\circ}$ plies. The measured failure strengths are compared with the predicted values.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.6
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• pp.1299-1308
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• 1994

This paper is considered on the dynamic behavior and the dynamic impact coefficient on the cable-stayed bridge under the vehicle load. The method of static analysis, that is, the transfer matrix method is used to get influence values about displacements, section forces of girder and cable forces. Gotten influence values were used as basic data to analyse dynamic behavior. This paper used the transfer matrix method because it is relatively simpler than the finite element method, and calculating speed of computer is very fast and the precision of computation is high. In the process of dynamic analysis, the uncoupled equation of motion is derived from simultaneous equation of the motion of cable-stayed bridge and vehicle travelling by using mode shape, which was borne from system of undamped free vibration. The solution of the uncoupled equation of motion, that is, time history of response of deflections, velocity and acceleration on reference coordinate system, is found by Newmark-${\beta}$ method, a kind of direct integral method. After the time history of dynamic response was gotten, and it was transfered to the time history of dynamic response of cable-stayed bridge by linear transformation of coordinates. As a result of this numerical analysis, effect of dynamic behavior for cable-stayed bridge under the vehicle load has varied depending on parameter of design, that is, the ratio of span, the ratio of main span length, tower height, the flexural rigidity of longitudinal girder, the flexural rigidity of tower, and the cable stiffness, investigated. Very good agreements with the existing solution in the literature are shown for the uncracked plate as well as the cracked plate.

• The Korean Society of Law and Medicine
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• v.12 no.2
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• pp.265-291
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• 2011

Changes in a drug's availability from prescription only to over-the-counter (OTC) status is of concern to physicians from both public health and individual patient perspectives. Government has generally been supportive of changes in medications from prescription(Rx) to over-the-counter (OTC) status in Korea, however, recognizing that there are both benefits and risks to any health care intervention, health care professionals are conservative in implementing changes to either the process or structure of health care. Changes in status of a drug from Rx to OTC can represent a change in both structure and process. Cost and convenience seem to be major factors in determining whether, given the choice, patients purchase a medicine over the counter or obtain it on prescription. With current arrangements, exemption from prescription charges provides an incentive to continue to obtain products on NHS prescription even when they are available over the counter. There is therefore no simple relation between the availability of over the counter medicines and the level of prescribing of deregulated products. The appropriate use of over the counter medicines-particularly those that have only recently been deregulated-places a burden of care on community pharmacists and calls for closer working relationships with general practitioners. In particular, systems for referral and for recording details of both prescribed and over the counter medicines need to be developed, and a direct route needs to be established for community pharmacists to report adverse drug reactions to over the counter products. Reclassification of prescription medicines-by making them available through pharmacies without a prescription-provides the opportunity for consumers to purchase a wider range of medicinal products without making a demand on NHS resources. There is, however, no simple relation between availability of over the counter medicines and demand for NHS prescriptions. In the late 1980s the UK government fuelled the over the counter market by making it easier to reclassify certain medicines from prescription only status to allow over the counter sale in pharmacies. To explore the influence of deregulation of medicines on NHS prescribing, this article presents analyses of consumer behaviour in using medicines and prescribers' attitudes to over the counter medication and collates findings from research. Policy makers should be aware that patients' expectations in relation to OTC medicines may be in conflict with evidence-based practice.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.11
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• pp.2150-2158
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• 1992

This study was carried out to investigate the flow structure and mixing process of a cross mixing flow formed by two round jets with respect to the ratio of mass flow rate. This flow configuration is of great practical relevance in a variety of combustion systems, and the flow behaviour of a cross jet defends critically on the ratio of mass flow rate and the cross angle. The mass flow rate ratios of two different jets were controlled as 1.0, 0.8, 0.6, and 0.4, and the crossing angle of two round jets was fixed at 45 degree. The velocities issuing from jet nozzle with an exit diameter of 20mm were adjusted to 40m/s, 32m/s, 24m/s, and 16m/s, and the measurements have been conducted in the streamwise range of $1.1X_0$to $2.5X_0$ by an on-line measurement system consisted of a constant temperature type two channel hot-wire anemometry connected to a computer analyzing system. The original air flow was generated by a subsonic wind tunnel with reliable stabilities and uniform flows in the test section. For the analysis of the cross mixing flow structure in the downstream region after the cross point, the mean velocity profiles, the resultant velocity contours, and the three-dimensional profiles depending upon the mass flow rate ratio have been concentrately studied.

• Journal of Preventive Medicine and Public Health
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• v.29 no.2 s.53
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• pp.159-172
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• 1996

A hospital-based case-control study was carried out to investigate the risk factors of uterine cervical cancer in Korea. Information on a wide-range of life-styles, which might be related with uterine cervix cancer, has been routinely collected through a dual application of the self-administered questionnaire and the direct interview by a well-trained nurse at the Department of Gynecology, Seoul National University Hosiptal since 1992. The number of cervical cancer cases, histologically confirmed at the hospital, were 284. Included were 939 women as controls, who were free of past history of any malignancies. Adjusted odds ratio and 95% confidence limits were based on the unconditional logistic regression model. The multivariate logistic model was constructed under the consideration of biologic characteristics on the natural history of the malignancy. In the multivariate results, the uterine cervical cancer risk was higher in women of shorter height$(P_{trend}<0.05)$, less educated spouse$(P_{trend}<0.001)$(0.001), multiple marriages(adjusted OR=2,70, 95% C.I. $1.64\sim4.47$), ever had a family history (adjusted OR=2.14., 95% C.I. $1.18\sim3.89$), multiparity$(P_{trend}<0.001)$, and early age at first $(P_{trend}<0.001)$. These results strongly suggest that the uterine cervix cancer might be related to the reproductive factors, and probably with sexual behaviour of both women and men in Korea.

• Journal of Korean Tunnelling and Underground Space Association
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• v.13 no.6
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• pp.431-450
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• 2011

When a circular vertical shaft is constructed below the groundwater level, additional forces caused by groundwater flow besides horizontal effective stresses will act on the wall. The inward direction of the groundwater flow will be inclined to the vertical wall and its direction will change depending on the wall depth. In this paper, to figure out the effect of seepage forces acting on the circular vertical shaft, the slope of the inclined flow varying with the depth is divided into vertical and horizontal components to derive the coefficient of earth pressure considering the seepage pressure and to obtain the vertical stress by taking the seepage pressure into account. The control volume in this study is assumed to be the same with that of the dry ground condition within which the earth pressure is acting on the wall by the creation of the plastic zone during shaft excavation. An example study shows that the vertical stress increases by about 1.4 times and the horizontal earth pressure increases up to 2.5 times compared to the dry ground condition. The estimated values from the proposed equation considering seepage forces and the calculated values from numerical analysis with "effective stress plus seepage force" show similar values, which verifies appropriateness of the proposed equation to estimate the earth pressure under the seepage condition.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.3
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• pp.443-448
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• 2008

Beak trimming in laying hens is a routine practice in which about 1/3-1/2 of the upper and lower beak is removed with the aim of reducing cannibalism. This experiment aimed to identify if this procedure causes pain by examining self-administration of an analgesic (carprofen) and pecking behaviour in 80 laying pullets beak-trimmed by two different methods at one day of age using hot-blade cauterisation or infra-red cauterisation. We also tested a control treatment, pullets with intact beaks, and a positive control treatment of pullets beak trimmed at 10 weeks of age which were expected to experience some pain due to recent severing of the underlying nerves in the beak. At 11 weeks of age birds trimmed at 10 weeks of age pecked more (p<0.001) gently ($0.6{\pm}0.06N$) at a disc attached to a force-displacement transducer than birds trimmed at 1 day of age with an infra-red machine ($0.9{\pm}0.1N$) or a hot blade ($1.1{\pm}0.07N$) and intact birds ($1.2{\pm}0.1N$). Maximum force of pecks recorded was also lower (p<0.001) in birds trimmed at 10 weeks of age than birds trimmed at 1 day of age with an infra-red method or a hot blade and intact birds. However, the pecking force in birds trimmed at 10 weeks of age was not increased by providing them with analgesic-treated feed, though birds that ate more carprofen had a higher maximum force of peck (p = 0.03). Pecking force in birds beak-trimmed at 1 day of age was the same as the pecking force of intact birds, and was unaffected by feeding pullets carprofen. A method of self-administration of an analgesic had previously revealed that chickens in neuromuscular pain arising from lameness consumed more of a feed containing carprofen than healthy chickens. However, we found no evidence that beak-trimmed pullets consumed more carprofen-treated feed than pullets with an intact beak. It should be noted that the three beak trimming methods resulted in an average 34% reduction in beak length, considered a light trim, and is perhaps not representative of commercial birds where greater portions of the beak are removed. We conclude that although carprofen has been reported to have an analgesic effect on neuromuscular pain in chickens, it appears to have no analgesic effect on potential neuropathic pain arising from the nerves severed by a light beak trim.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7789-7794
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• 2015

Background: This study aimed to evaluate the impact of a community-based health education and communication programme on reducing liver fluke infections caused by the consumption of uncooked fish among people in a high-risk area of Thailand. Materials and Methods: The study was quasi-experimental in nature, with three-stages. Stage 1 involved a situational and capacity analysis of designated communities in Khon Kaen province. This was followed by the development of a model for community-based health education and communication to prevent liver fluke infections among high-risk people, and, lastly, implementation and evaluation of the model were performed. Data were collected using both qualitative and quantitative methods. In total, 390 people were surveyed, and quasi-experimental and comparison groups, each with 90 people, were assessed between May 2011 and April 2012. Analysis was using statistical OR, 95 % CI, the Willcoxon matched pairs signed ranks test, the chi-square test, and the Mann-Whitney U test. Results: The findings showed that most respondents had a high level of knowledge and understanding of liver fluke disease (89.5%, 95% CI:86.0-92.4), and positive attitudes toward the prevention of the disease (94.4%, 95% CI:91.6-96.4). However, with regard to changes in consumption of uncooked fish, most respondents were still in the pre-contemplation phase (55.1%, 95% CI:50.0-60.1), followed by the contemplation phase, 22.6%. Furthermore, four factors were found to be associated with the consumption of uncooked fish - the consumption of alcohol (OR 4.16, 95% CI:1.79-9.65), gender (OR 3.17, 95% CI:1.53-6.54), smoking (OR 3.03, 95% CI:1.31-7.05), and age 40 years and above (OR 2.68, 95% CI:1.02-7.05). After nine months of the health education and communication programme using local media based on local wisdom, culture and persons, the results showed that, compared to the control group, members of the experimental group had a higher level of knowledge, a better attitude and lower levels of ill-advised consumption behaviour. Also, it was found that consumption of uncooked fish, by an assessment of the level of stage of change, was reduced. (p-value 0.002). Conclusions: The health education and communication programme developed as part of the study was effective in changing the consumption of uncooked fish. Therefore, this approach should be promoted in other high-risk areas in Thailand in the future.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6311-6318
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• 2012

Background: HER2/neu overexpression due to gene amplification is an important factor in breast cancer, modifying the sensitivity to anti-HER2 monoclonal antibody therapy. The clinical significance of HER2 expression in non small cell lung carcinoma (NSCLC) is currently under evaluation. The tumor suppressor gene PTEN negatively regulates the HER2/PI3K/Akt signalling pathway. The purpose of this study was to evaluate the role of simultaneous alteration in HER2 and PTEN protein expression in relation to biological behaviour of NSCLCs. Materials and Methods: Protein expression was determined by immunohistochemistry in sixty-one (n=61) NSCLC cases along with CISH for HER2 gene analysis and detection of chromosome 17 aneuploidy. Patients were followed-up for a period of 34 to 41 months after surgery. Results: HER2 overexpression (2+/3+score) was detected in 17 (27.9%) patients while loss of PTEN expression was observed in 24 (39.3%) cases, low expression in 29 (47.6%) and overexpression in 8 (13.1%). Simultaneous HER2 overexpression and PTEN low/loss of expression were correlated with metastasis (71.4% vs 36.2% p=0.03). Analysis in the subgroup of 22 patients of pTNM stage III with lymph node status N1 or N2 revealed that there was a relationship between the number of positive regional lymph node groups and simultaneous deregulation of the two genes (p=0.04). Multivariate analysis determined that HER2 overexpression was associated with an increasing risk of developing metastases (OR: 4.3; 95%CI: 1.2-15.9; p: 0.03) while PTEN overexpression was associated with lower risk (OR: 0.1; 95%CI: 0.1, 1.0; p: 0.05). Conclusions: Simultaneous HER2/PTEN deregulation is a significant genetic event that leads to a more aggressive phenotype of NSCLC.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.9
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• pp.4491-4501
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• 2016

Verruco-papillary lesions (VPLs) of the oral cavity described in the literature involve a spectrum of conditions including squamous papilloma, verruca vulgaris, focal epithelial hyperplasia, condyloma, proliferative verrucous leukoplakia and verrucous carcinoma. A majority of the VPLs are slow growing, benign in nature and have a viral aetiology. Virus associated benign mucosal outgrowths are not too difficult to diagnose either clinically or by microscopy. Apart from virus-associated lesions, VPLs harboring malignant potential or behaviour such as verrucous carcinoma, proliferative verrucous leukoplakia, oral verrucous hyperplasia (OVH), oral papillary squamous cell carcinoma (PSCC) and oral conventional squamous cell carcinoma with papillary features (CSCC) need to be further clarified for better understanding of their predictable biologic behavior and appropriate treatment. Current understanding of potentially malignant VPLs is perplexing and is primarily attributed to the use of confusing and unsatisfactory terminology. In particular, the condition referred to as oral verrucous hyperplasia (OVH) poses a major diagnostic challenge. OVH represents a histopathological entity whose clinical features are not well recognised and is usually clinically indistinguishable from a verrucous carcinoma and a PSCC or a CSCC. A consensus report published by an expert working group from South Asia as an outcome of the 'First Asian Regional Meeting on the Terminology and Criteria for Verruco-papillary Lesions of the Oral Cavity' held in Kuala Lumpur, Malaysia, recognised the clinical description of these OVH as a new entity named 'Exophytic Verrucous Hyperplasia'. Previously described clinical features of OVH such as the 'blunt' or 'sharp' variants; and the 'mass' or 'plaque' variants can now collectively fall under this newly described entity. This paper discusses in detail the application of the standardized criteria guidelines of 'Exophytic Verrucous Hyperplasia' as published by the expert group which will enable clinicians and pathologists to uniformly interpret their pool of OVH cases and facilitate a better understanding of OVH malignant potential.