• Advances in concrete construction
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• v.2 no.1
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• pp.13-27
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• 2014

The principal objective of this study is to deepen the characterization studies already led on sand concretes in previous works. Indeed, it consists in studying the effect of the sand type on the main properties of sand concrete: fracture and mechanical properties. We particularly insist on the determination of the fracture characteristics of this material which apparently have not been studied. To carry out this study, four different types of sand have been used: dune sand (DS), river sand (RS), crushed sand (CS) and river-dune sand (RDS). These sands differ in mineralogical nature, grain shape, angularity, particle size, proportion of fine elements, etc. The obtained results show that the particle size distribution of sand has marked its influence in all the studied properties of sand concrete since the sand having the highest diameter and the best particle size distribution has given the best fracture and mechanical properties. The grain shape, the angularity and the nature of sand have also marked their influence: thanks to its angularity and its limestone nature, crushed sand yielded good results compared to river and dune sands which are characterized by rounded shape and siliceous nature. Finally, it should further be noted that the sand concrete presents values of fracture and mechanical properties slightly lower than those of ordinary concrete. Compared to mortar, although the mechanical strength is lower, the fracture parameters are almost comparable. In all cases, the sand grains are debonded from the paste cement during the fracture which means that the crack goes through the paste-aggregate interface.

• Women's Health Nursing
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• v.15 no.1
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• pp.54-63
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• 2009

Purpose: This study was done to develop an integrated breast health program for prevention and early detection of breast cancer, integrating primary and secondary prevention factors using cognitive-behavioral strategies. Method: This methodological study conducted as follows; Selection of components for the program through a literature review, survey to identify women's knowledge and risk perception of breast cancer and diet, and building prototype for the program using discussion based on findings. Using structured questionnaires, interviews were done with 130 women aged 40-59 who lived in a rural area. Result: Primary prevention (diet pattern, knowledge about breast cancer, and risk perception) and secondary prevention (early detection behaviors) factors were identified through the literature review. The survey showed that women lack knowledge and awareness about the risks of breast cancer, and have a low compliance rate for early detection behavior. Based on these results, a program was developed utilizing counseling and models to provide education and practice related to diet, breast cancer, and early detection behaviors. Conclusion: Use of this integrated and tailored breast health program with women at risk will contribute to better breast health, but further study is needed to verify the effects.

• Journal of the Institute of Convergence Signal Processing
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• v.4 no.2
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• pp.53-60
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• 2003

For the high center of gravity vehicles the roll stiffness of their suspensions is arranged to be very high because such vehicles are in some danger of tipping over in cornering. In some cases, the effective roll stiffness is determined significantly by the compliance of the tires because of the very stiff anti-roll members incorporated in the suspension. In such cases, it is clear that the shock absorbers which may be effective in damping heave oscillations have little effect on roll oscillations. Therefore, wind gusts and roadway unevenness may cause large swaying oscillations. In this paper, to improve the stability for the high center of gravity vehicles a control scheme to augment the damping of the roll mode is proposed. As the feedback signals needed to provide damping of the roll motion, the front or rear steer angles or both are chosen because they are very related to roll motion. The scheme is effective from moderate to high speeds and stabilizes the roll mode without introducing disturbance moments from roadway unevenness as shock absorbers do. The validity on the proposed method is verified through the computer simulation.

• Food Science of Animal Resources
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• v.36 no.3
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• pp.319-325
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• 2016

This study was conducted to determine the residual amount of veterinary drugs such as meloxicam, flunixin, and tulathromycin in animal products (beef, pork, horsemeat, and milk). Veterinary drugs have been widely used in the rearing of livestock to prevent and treat diseases. A total of 152 samples were purchased from markets located in major Korean cities (Seoul, Busan, Incheon, Daegu, Daejeon, Gwangju, Ulsan and Jeju), including Jeju. Veterinary drugs were analyzed by liquid chromatography-tandem mass spectrometry according to the Korean Food Standards Code. The resulting data, which are located within 70-120% of recovery range and less than 20% of relative standard deviations, are in compliance with the criteria of CODEX. A total of five veterinary drugs were detected in 152 samples, giving a detection rate of approximately 3.3%; and no food source violated the guideline values. Our result indicated that most of the veterinary drug residues in animal products were below the maximum residue limits specified in Korea.

• Journal of the Korean Society of Safety
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• v.28 no.2
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• pp.78-83
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• 2013

The traffic culture index is used as a major index in evaluating the traffic safety services of local governments and also serve as important data for the planning and implementation of traffic safety services. However, as the traffic culture index gradually became a standard for comparison among local governments, in part, certain cases arose which questioned the grounds for selecting variables for the index and the validity of the index in terms of its influential relationship between evaluation items. This study analyzed the index's influential relationship by utilizing a PLS structural equation model based on the evaluation results of the 2011 traffic culture index. A variable-linking model was created which recognized the relativity taking into account of the indirect effects between latent variables and this model was proven to be a model suitable in explaining the traffic culture index with a 97.8% explanation power. It was found that traffic safety(0.530), driving behavior(0.527), pedestrian behavior(0.187) and vulnerable road users(0.147), in such order, had an effect on the traffic culture index. It was also found that human casualties due to traffic accidents under "traffic safety" and traffic light compliance rate under "driving behavior" had an important effect. The study showed that motor vehicle share in illegal parking in school zones did not have a valid explanation power regarding "vulnerable road users".

• Fire Science and Engineering
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• v.34 no.2
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• pp.49-53
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• 2020

This study aimed to identify the characteristics of 40 chemical accidents that occurred in Jeollabuk-do from 2004 to 2019. During this time, there were 2.5 accidents per year on average in the province; their types were classified as spill/leak, fire, explosion, adverse reaction, and complex. There were 34 leaks and six explosions, and they are categorized as follows: 12 by worker error, 16 from facility defects, and 12 by transport vehicle accidents. The substances involved in these accidents were ammonia (15%), sulfuric acid (12.5%), and silicon tetrachloride (7.5%). Notably, the rate of chemical accidents (75%) is the highest during spring and summer. In order to reduce chemical accidents, first, there should be compliance with the relevant laws. Second, the quality of safety education and training of workers should be improved. Finally, valuable government support is also necessary to improve facilities.

• Journal of Korean Academy of Nursing Administration
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• v.8 no.1
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• pp.85-95
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• 2002

The purpose of this study was to develope a critical pathway for the chemotherapy of non-small cell lung cancer patients and to identify its effects after implementation. Critical pathway was developed through 5 steps including content and clinical validity tests with collaborative efforts of nurses, clinicians, and other allied healthcare professionals with the aim of improving the quality of patient care, while minimizing cost to the patients. This paper was described an evaluation of the impact of a developed critical pathway on complication rate, length of stay, costs, the interval of treatment and patient satisfaction by nonequivalent control group posttest-only non-synchronized research design.Results were compared between the two groups of patients. There were no significant differences in demographic variables and the occurrence of bone marrow suppression between experimental group and control group(t=-0.01, p=0.992). There were statistically significant decreases in the average length of stay(t=-10.45, p=0.000), in the average cost(t=-2.988, p=0.004), and in the interval of treatment(t=-6.75, p=0.000) after implementation of the critical pathway compared to control group. Also, there was a statistically significant improvement of the patient satisfaction after implementation of the critical pathway compared to control group(t=4.57, p=0.000). This paper concludes that critical pathway in chemotherapy for lung cancer, implemented in the context of an general hospital, is the useful tool to shorten the hospital stay, reduce treatment costs, and improve the quality of life in cancer patients. Further study needs to be conducted to identify other clinical outcomes including job satisfaction, collaboration among health professionals and potential for use in education. Also, it is recommended that nurses should revise continuously the developed critical pathway through clinical implementation and maintain their role of patient advocacy through monitoring pathway compliance.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.19
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• pp.8259-8263
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• 2014

Aims: To determine the clinical characteristics, pathological features, local and distant failure patterns in patients with carcinoma of major salivary glands treated with surgery and postoperative radiotherapy (PORT). Materials and Methods: We retrospectively reviewed 106 cases of major salivary gland tumor seen at our centre (1998-2008). Sixty five cases of major salivary gland carcinoma were selected for analysis (exclusions: benign, palliative, non-carcinomas). The patient population treated by surgery and PORT was divided into two groups: 1) Patients who underwent surgery and immediate PORT (Primary PORT); 2) Patients with recurrent carcinoma who underwent at least two surgeries and received PORT in the immediate post-operative period of the last performed surgery (Recurrent PORT). Recurrence free survival (RFS) was assessed using the Kaplan-Meier method. Results: Median age was 35 years with a male: female ratio of 1.3:1. The majority of cancers were located in the parotid gland (86.2%) and the most common histology was mucoepidermoid carcinoma (43%). Thirty nine cases (60%) were primary while 26 (40%) were recurrent. Optimal surgery was performed in 59/65 patients (90.8%). 43 patients (66.2%) underwent neck dissection, of which 14 (32.5%) had nodal metastasis. Overall, 61 (93.8%) patients complied with the prescribed radiotherapy. Median dose of PORT was 60 Gy. Median follow-up was 13.1 months (range 2-70). Relapse free survival was 50.4% at 60 months. Some 12 cases (18.5%) recurred with a median time to recurrence of 16.9 months. Conclusions: Surgery and PORT is an effective treatment for major salivary gland carcinoma with over 90% compliance and <20% recurrence. Early treatment with postoperative radiotherapy may increase the survival rate in major salivary gland carcinoma patients.

• Plant Journal
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• v.16 no.1
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• pp.38-43
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• 2020

In this study, Seochon Thermal Power Plant No.1 for anthracite coal was tested to find the proper operation range of limestone slurry pH in the absorber tower which can be operated continuously in compliance with the Air Quality Preservation Act and Seocheon Thermal Power Division's internal regulation, sulfur dioxide average emission regulation. When operating the sulfur dioxide concentration [ppm] in the combustion gas flowing into the desulfurization absorption tower at 370, 400, 460 and 550 ppm while the main operating elements such as the flow rate of the combustion gas were fixed, the proper slurry pH Were 4.4, 4.5, 4.8 and 5.1, respectively. Therefore, it is recommended to operate with the correlation equation, R_pH=0.004×C_in+2.93 derived using sulfur dioxide and the appropriate slurry pH.

• Journal of Information Technology Services
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• v.18 no.5
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• pp.165-182
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• 2019

An equity crowdfunding system of Korea has been introduced since January 25, 2016. The crowdfunding has contributed to remove the funding gap for startups in Korea. In the three years since the introduction of the system, the amount issued has been growing annually 31 percent. In 2018, the general investors who participated in equity crowdfunding, account for 93.8% of the total market size. General investors are a large part of equity crowdfunding. Investors, however, are facing the information asymmetry problems. General investors rely heavily on the investment prospectus provided by startups to obtain the information they need to determine their investment decisions. Under these circumstances, startups have the incentive to provide information that is advantageous to them, and investors are likely to be adversely affected by the investment prospectus. In this study, we collected the novel crowdfunding prospectus dataset: a total of 459 investment prospectus and conducted a morphological analysis. The analysis showed that the more positive the word, the higher the success rate of investors' subscriptions. We also compared projects that were heavily invested by general investors with projects that were heavily invested by professional investors. Then, we were able to examine that the success rates of project subscription, which were heavily invested by general investors, were higher than the projects of professional investor type. It can be interpreted as a general investor driven crowdfunding market. Based on these results, we propose three policies. First, the supervisor should be strengthened to provide more detailed information on investment risk factors in the prospectus. Second, the crowdfunding intermediary should monitor information provided by startups. Third, an investor should be asked to add a question to the investment compliance test that allows the investor to recognize the problem in the manual.