• Structural Engineering and Mechanics
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• v.69 no.6
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• pp.699-712
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• 2019

A cable-stayed bridge (CSB) is one of the most complicated structures, especially when subjected to earthquakes and taking into consideration the effect of soil-structure-interaction (SSI). A CSB of a 500 m mid-span was modeled by the SAP2000 software and was subjected to four different earthquakes. To mitigate the harmful effect of the vibration generated from each earthquake, four mitigation schemes were used and compared with the non-mitigation model to determine the effectiveness of each scheme, when applying on the SSI or fixed CSB models. For earthquake mitigation, tuned mass damper (TMD) systems and spring dampers with different placements were used to help reduce the seismic response of the CBS model. The pylons, the mid-span of the deck and the pylon-deck connections are the best TMDs and spring dampers placements to achieve an effective reduction of the earthquake response on such bridges.

• Journal of the Korean Wood Science and Technology
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• v.50 no.2
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• pp.104-112
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• 2022

Indoor air quality is a very important environmental factor in modern society. However, air pollutants generated from various interior construction materials significantly affect the human body, including formaldehyde (HCHO) and volatile organic compounds that threaten public health by deteriorating indoor air quality. Effective in removing these harmful substances are porous materials, such as woodceramics. In this study, charcoal, a porous material, was added to rice husk, an agricultural by-product, and sawdust generated during the sawing process to prepare boards and ceramics at different mixing ratios, and the HCHO deodorization performance and far-infrared emission characteristics were measured. As the mixing ratio of charcoal increased, the deodorization rate of the boards and ceramics tended to increase. Overall, the deodorization rate was measured to be 80% to 90%, indicating that the boards and ceramics prepared with charcoal are suitable to be used for the purpose of deodorization. The effect of the material mixing ratio on far-infrared emissivity and emission power was insignificant.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.111-118
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• 2022

Conflicts in public construction projects become more serious and complex so that they have a negative effect on performance of projecets. Conflicts in public construction projects are defined as expanding in complaints. This study analyzes the relationship structure and effect on performance between complaints and conflicts. First of all, 219 survey data collected from industry experts were used to derive complaints arising from the project and to understand the characteristics of each complaint. In the case of environmental damages, rather than environmental damage during construction, harmful substances or effects that can occur in completed facilities cause complaints from local residents, and opposition from environmental groups has a great effect on time and cost increase. As for safety damage, civil complaints related to prevention and countermeasures for safety accidents occur frequently, and additional construction affects cost increases. Through this study, it is possible to understand the serious complaints that are prone to conflict in public construction projects, their frequency, and the performance of the project.

• The Korean Nurse
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• v.36 no.5
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• pp.91-100
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• 1998

This study aims to investigate smoking patterns in high school student and to give student smoker effective information. The sample of 250 male highschool students out of two different schools in Tae-Jon was questioned from July 10th to 15th. 1995. In analyzing these date. the statistics shows the realities by means of number of students. The results are summarized into 17 items as follows. Regarding the level of smoking. 140 students out of 250 admit that they have ever smoked. 52.1% of smoking students say that the motivation of beginning smoking is mainly curiosity. The survey shows that 22.9% of smoking students feel very good when smoking. It also shows that 30.0% of smoking students began smoking in the first grade of high school. With regard to the volume of smoking per day. 41.4% of smoking students smoke variably. 42.1% drink when smoking. 15.0% spend more than W 70.000 a month. About the question who knows the fact of their smoking. 51.5% answer that their friends know the fact of their smoking. In regard to the resaltionship between smoking and school per-formance. 18.2% of non smoking students make poor grades as compared with 40% of smoking students. 9.3% of smoking students say that they are satisfied with the school life. but 35.7% of them are not satisfied. Regarding the attitude to smoking teachers. 35% of smoking students state that they are affected by them. 69.3% of smoking students say that they will stop smoking. while the remaining 30.7% say that they will keep smoking. The reason of 63.9% to stop smoking is that smoking is bad for the health. The reason of 46. 5% to keep smoking is the acquired habit of smoking. 97.2% know the fact that the major element of cigarettes is nicotine and it is very harmful to the health. 40.8% recognize the harmful effect of smoking by TV and radio programs. 97.2% know that smoking could cause lung cancer. From the above results. I propose as follows We should make specific plan to keep smoking by simple curiosity from being developed into habitual smoking. We should teach them how harmful smoking is and make them stop smoking by themselves. It is very essential for family members and teachers to give continuous interest since childhood. As the teacher affect the students very much, they should give up smoking first. The incidence of smoking should be identified in each of the middle and high schools. smoking prohibition programs relevant to each school should be developed and implemented. The local community should ban cigarette vending machines. Cigarettes should not be sold to adolescents. By setting every place where adolescents gather including schools nonsmoking area. we should decrease their impulse to smoke. then smoking opportunities. and harmful effects to them caused by passive smoking.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.6 no.3
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• pp.383-391
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• 2016

Ballast water provides stability and manoeuvrability to a ship. Foreign harmful aquatic organisms, which were transferred by ballast water, cause disturbing ecosystem. In order to minimize transference of foreign harmful aquatic organisms, IMO(International Maritime Organization) adopted the International Convention for the Control and Management of Ship's Ballast Water and Sediments in 2004. If the convention take effect, a port authority might need to check that ballast water is properly disposed of. In this paper, we propose a method of counting harmful aquatic organisms in ballast water thorough image processing. We extracted three samples from the ballast water that had been collected at Busan port in Korea. Then we made three grey-scale images from each sample as experimental data. We made a comparison between the proposed method and CellProfiler which is a well known cell-counting program based on image processing. Setting of CellProfiler is empirically chosen from the result of cell count by an expert. After finding a proper threshold for each image at which the result is similar to that of CellProfiler, we used the average value as the final threshold. Our experimental results showed that the proposed method is simple but about ten times faster than CellProfiler without loss of the output quality.

• Korean Journal of Culture and Social Issue
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• v.9 no.2
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• pp.61-78
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• 2003

The researcher examined the relationship between dating violence and drinking behaviors. Study participants included 440 Korean College students(184 males and 256 females) currently involved in heterosexual dating relationships. Participants' ages ranged from 17 to 30(M=20.08, SD=1.89). Questionnaires and psychological tests used included: Straus' Conflict Tactics Scale, Alcohol Use Disorder Identification Test(AUDIT), Cooper's Revised Drinking Motives Questionnaire(DMQ), and Index of Family Alcohol Use. Research designs were 2(gender) × 2(experience of inflicting dating violence), i.e. 2-way MANOVAs. Results suggest students who drink one or more times a week are more likely to commit acts of violence toward their dating partners than students drinking less often. The study revealed males tend to drink with higher social, enhancement, conformity and coping motives than females. The study also showed that students inflicting dating violence drank with higher coping motives than students who did not. Males showed more hazardous, dependent and harmful drinking patterns than females. Also, students who had inflicted dating violence showed a higher degree of these characteristics (hazardous, dependent and harmful drinking patterns) along with a greater family history of alcohol use than participants who had not inflicted dating violence. The findings showed significant 2-way interactions in dependent and harmful drinking patterns. Simple main effect analysis revealed that differences in dependent and harmful drinking patterns in males are more significant than the same differences in females.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.11
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• pp.4929-4934
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• 2016

Cancer, a worldwide epidemic disease with diverse origins, involves abnormal cell growth with the potential to invade other parts of the body. Globally, it is the main cause of mortality and morbidity. To overcome the drawbacks of the commercially available chemotherapies, natural products-loaded nano-composites are recommended to improve cancer targetability and decrease the harmful impact on normal cells. This study aimed at exploring the anti-cancer impacts of Moringa oleifera seed oil in its free- (MO) and nano-formulations (MOn) through studying whether it mechanistically promotes mitochondrial apoptosis-mediating cell death. Mitochondrial-based cytotoxicity and flow cytometric-based apoptosis analyses were performed on cancer HepG2, MCF7, HCT 116, and Caco-2 cell lines against normal kidney BHK-21 cell line. The present study resulted that MOn triggered colorectal cancer Caco-2 and HCT 116 cytotoxicity via mitochondrial dysfunction more powerful than its free counterpart (MO). On the other side, MOn and MO remarkably induces HCT 116 mitochondrial apoptosis, while sparing normal BHK-21 cells with minimal cytotoxic effect. The present results concluded that nano-micelle of Moringa oleifera seed oil (MOn) can provide a novel therapeutic approach for colorectal and breast cancers via mitochondrial-mediated apoptosis, while sparing normal and even liver cancer cells a bit healthy or with minimal harmful effect. Intriguingly, MOn induced breast cancer not hepatocellular carcinoma cell death.

• Food Science and Preservation
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• v.14 no.1
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• pp.87-93
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• 2007

This study investigated the antimicrobial effect of germinated acorn pollen solution on harmful food-borne microorganisms. The antimicrobial activity when 8% (w/v) acorn pollen in 10% (w/v) sugar solution was extracted at $30^{\circ}C$ for 4 days. The minimal inhibitory concentration of this germinated acorn pollen solution was $40\;{\mu}L/mL$ for Gram-positive bacteria and $30\;{\mu}L/mL$ for Gram-negative bacteria. Acetic and lactic acids were present at high levels in germinated acom pollen solution. As pollen germination releases heat, the antimicrobial activities are heat-stable. The activities are tolerant of low pH. In summary, acorn pollen germination solution showed active antibiosis and should be developed as a natural preservative material.

• Korean Journal of Environmental Biology
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• v.27 no.2
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• pp.140-145
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• 2009

All organisms are being exposed to harmful factors present in the environmental. The combined action of various factors is a distinguishing feature of modern life. An interaction between two chemicals is considered as synergistic when the effect produced is greater than the sum of the two single responses. The biological effects due to the combined action of ionizing radiation with the other factor are hard to estimate and predict in advance. In the current study, we investigated the synergistic effects between ionizing and $HgCl_2$ using fish hepatoma cells (PLHC-1 cells). The results showed a dramatic decrease of cell viability after simultaneous treatment of PLHC-1 cells with ionizing radiation and $HgCl_2$. Neiither of the two had any cytotoxic effect when treated alone. The cytotoxicity of ionizing radiation was enhanced in the presence of $HgCl_2$. The synergistic effects were observed after exposure of the PLHC-1 cells to ionizing radiation combined with $HgCl_2$. The synergistic interaction was due to an increase of irreversibly damaged cells after the combined exposure. Analysis of the extent of synergistic interaction enables to make quantitative estimation of irreversibly damaged cells after the combined exposure. The present study suggests that PLHC-1 cells can serve as rapid screening tools for detecting the toxicity of harmful factors.

• Tribology and Lubricants
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• v.34 no.6
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• pp.292-299
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• 2018

The objective of this research is to investigate the impact of engine oil aging on PM(Particulate Matter), exhaust gases, and DPF. It is widely known that the specification of a lubricant and its consumption in an ICE considerably influences the release of regulated harmful emissions under normal engine operating conditions. Considering DPF clogging phenomena associated with lubricant-derived soot/ash components, a simulated aging mode is designed for DPF to facilitate engine dynamometer testing. A PM/ash accumulation cycle is developed by considering real-world engine operating conditions for the increment of engine oil consumption and natural DPF regeneration for ash accumulation. The test duration for DPF aging is approximately 300 h with high- and low-SAPs engine oils. Detailed engine lubricant properties of new and aged oils are analyzed to evaluate the effect of engine oil degradation on vehicle mileage. Furthermore, physical and chemical analyses are performed using X-CT, ICP, and TGA/DSC to quantify the engine oil contribution on the PM composition. This is achieved by sampling with various filters using specially designed PM sampling equipment. Using high SAPs engine oil causes more PM/ash accumulation compared with low SAPs engine oils and this could accelerate fouling of the EGR in the engine, which results in an increase in harmful exhaust gas emissions. These test results on engine lubricants under operating conditions will assist in the establishment of regulated and unregulated toxic emissions policies and lubricant quality standards.