• Journal of Advanced Marine Engineering and Technology
• /
• v.41 no.4
• /
• pp.323-329
• /
• 2017

Nowadays, considering global warming and enhanced prohibition to discharge pollutants at sea, all of existing operation-ships must lead to the reduction of fuel consumption. International standards of International Maritime Organization and EU rules governing harbor pollutants are being strengthened. Therefore, ship-owners and operators are seeking ways to reduce $CO_2$, SOx, and NOx emissions. Although world trade continues to expand, total fuel usage for sea transport tends to diminish. However, ICS(International Chamber of Shipping) has set a goal of reducing $CO_2$ emissions from shipping by 50% until 2050. In addition, with respect to the Paris Climate Change Accord in 2015, IMO proposes to set up a reduction target of GHG emission from existing operation-ships. For setting up a reduction target of GHG from international maritime transport, "A data collection system for fuel consumption" will be introduced in the near future. In order to effectively reduce the use of fuel in a ship in accordance with the trend of compulsory fuel saving from operation ships, this paper suggested adoption of an Incentive-Penalty scheme based on Emission-Trading-Scheme, Carbon Tax, and basic calculation formula after verifying the EEOI level for a year.

• Journal of the Korean School Mathematics Society
• /
• v.17 no.4
• /
• pp.507-539
• /
• 2014

The algebra is an important tool influencing on a mathematics in general. To make good use of the algebra, it is necessary to transfer from a given situation to a proper algebraic representation. But some research in related to algebraic word problems have reported the difficulty changing to a proper algebraic representation. Our study have focused on transformation and elaboration of algebraic representation. We investigated in detail the responses and perceptions of 29 Grade 7 students while transforming to algebraic representation, only concentrating on the literature expression form the problematic situations given. Most of students showed difficulties in transforming both descriptive and geometric problems to algebraic representation. 10% of them responded wrong answers except only a problem. Four of them were interviewed individually to show their thinking and find the factor influencing on a positive elaboration. As results, we could find some characteristics of their thinking including the misconception that regard the problem finding a functional formula because there are the variables x and y in the problematic situation. In addition, we could find the their fixation which student have to set up the equation. Furthermore we could check that making student explain own algebraic representation was able to become the factor influencing on a positive elaboration. From these, we also discussed about several didactical implications.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.2
• /
• pp.1005-1010
• /
• 2014

Background: A relation between abdominal obesity and colorectal tumor development has been reported repeatedly, and is believed to be more remarkable in man than in women. However, the details vary depending on scientific reports. This may be due at least partly to the selected surface anthropometric index in addition to the influence of gender and ethnic groups. To cope with this, we considered a new index of abdominal obesity and evaluated its risk prediction potential. Materials and Methods: Six hundred ninety five Japanese (262 women and 433 men) who had a colonoscopy were studied. The new index was named as waist circumference to height index (WHI) and was calculated by the formula of waist circumference (cm)/height (m)/height (m). Biochemical and lifestyle factors were investigated preceding the colonoscopy. Statistical analysis was performed using SPSS for Windows. Results: Increase of WHI was associated with altered metabolism of carbohydrate and lipid in both women and men. WHI was positively related with the development of colon tumor of women, while not with that of men. Logistic regression analysis performed for stratified age groups (45-54, 55-64 and 65-74 years) showed that WHI significantly increased odds ratio to 1.31 (CI 1.05-1.64 p=0.01) in women of 55-65 years. In contrast, in men this index WHI reduced the odds ratio insignificantly, while low density lipoprotein and triglyceride significantly increased the odds ratio to 1.01 (CI 1.00-1.03 p=0.02) in the 55-65 year group and to 1.02 (CI 1.00-1.03 p=0.02) in the 45-55 year group. Conclusions: In Japanese the risk factors for colon tumor development are different between women and men. WHI is a simple and efficient predictor of colon tumor risk in Japanese women and may be used to select those who should have colonoscopy.

• The Journal of the Korea Contents Association
• /
• v.11 no.8
• /
• pp.475-487
• /
• 2011

In this paper, we present a systematic method to derive spectrum of high-order pulse and a novel design of e-Learning system that deals with deriving the spectrum using concept-based branching method. Spectrum of high-order pulse can be derived using conventional methods including 'Consecutive Differentiations' or 'Convolutions', however, their complexity of calculation should be too high to be used as the order of the pulse increase. We develop a recursive algorithm according to the order of pulse, and then derive the formula of spectrum connected to the order with a newly designed look-up table. Moving along, we design an e-Learning content for studying the procedure of deriving high-order pulse spectrum described above. In this authoring, we use the concept-based object branching method including conventional page or title-type branching in sequential playing. We design all four Content-pages divided into 'Modeling', 'Impulse Response and Transfer Function', 'Parameters' and 'Look-up Table' by these conceptual objects. And modules and sub-modules are constructed hierarchically as conceptual elements from the Content-pages. Students can easily approach to the core concepts of the analysis because of the effects of our new teaching method. We offer step-by-step processes of the e-Learning content through unit-based branching scheme for difficult modules and sub-modules in our system. In addition we can offer repetitive learning processes for necessary block of given learning objects. Moreover, this method of constructing content will be considered as an advanced effectiveness of content itself.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.10
• /
• pp.94-105
• /
• 2020

Recently, most studies of 3D printing in construction have focused on the development of 3D printers and materials suitable for construction 3D printers. In comparison, there has been little research on design support tools that enable representative BIM data of building modeling tools to be applied to 3D printing. In addition, existing 3D printing slicing programs are commercialized around manufacturing, showing that they are unsuitable for construction 3D printing. Therefore, this research aims to develop a design support tool for 3D printing for buildings. The developed design support tool was validated based on arbitrary BIM data. Verification showed that wall pattern generation was modeled accurately without errors, and a calculation of the construction period showed that the formula presented in this study was valid. Furthermore, the maximum length of the mesh split was set to 100mm to minimize errors when converting to STL files.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2007.10a
• /
• pp.473-476
• /
• 2007

Location determination of mobile user via RSSI approach has received ample attention from researchers lately. However, it remains a challenging issue due to the complexities of RSSI signal propagation characteristics, which are easily exacerbated by the mobility of user. Hence, a segmentation-based linear spline interpolation method is proposed to cater for the dynamic fluctuation pattern of radio signal in complex environment. This optimization algorithm is proposed in addition to the current radiolocation's (CC2431, Chipcon, Norway) algorithm, which runs on IEEE802.15.4 standard. The enhancement algorithm involves four phases. First phase consists of calibration model in which RSSI values at different static locations are collected and processed to obtain the mean and standard deviation value for the predefined distance. RSSI smoothing algorithm is proposed to minimize the dynamic fluctuation of radio signal received from each reference node when the user is moving. Distances are computed using the segmentation formula obtain in the first phase. In situation where RSSI value falls in more than one segment, the ambiguity of distance is solved by probability approach. The distance probability distribution function(pdf) for each distances are computed and distance with the highest pdf at a particular RSSI is the estimated distance. Finally, with the distances obtained from each reference node, an iterative trilateration algorithm is used for position estimation. Experiment results obtained position the proposed algorithm as a viable alternative for location tracking.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.3
• /
• pp.488-496
• /
• 2020

This study was based on nitrate chemical accidents at home and abroad. Toxic gases due to adverse reactions are generated in the workplace, laboratory, hospital, container damage, and chemical misinjection. Through a case review of possible situations and safety, this study analyzed various cases of accidents, accident status, accident type, cause of the accident, location of the accidents, etc. from 2014 to 2018. The plans for improvement in education and nitrate accidents were reviewed. As a result, 36 nitrate chemical accidents were investigated, including 16 careless worker accidents, eight transportation accidents, and 12 facilities shortages. Nitrate chemical accidents are occurring continuously. Based on this, the range of toxic effects using CARIS was calculated at the worst-case scenario, and the effective response range was measured through the damage impact range. For this purpose, the impact range was predicted based on the strengthening of safety education, emergency action plan and correlation, and the quantified data was identified. In addition, the reliability of the scope of impact was reviewed based on the correlation formula that could facilitate the evacuation of residents, and it was applied to actual accident scenarios of the workplace to present the effects of the accident response and preventive measures.

• Archives of Plastic Surgery
• /
• v.44 no.1
• /
• pp.26-33
• /
• 2017

Background The purpose of this study was to assess the correlation between the 2-dimensional (2D) extent of orbital defects and the 3-dimensional (3D) volume of herniated orbital content in patients with an orbital wall fracture. Methods This retrospective study was based on the medical records and radiologic data of 60 patients from January 2014 to June 2016 for a unilateral isolated orbital wall fracture. They were classified into 2 groups depending on whether the fracture involved the inferior wall (group I, n=30) or the medial wall (group M, n=30). The 2D area of the orbital defect was calculated using the conventional formula. The 2D extent of the orbital defect and the 3D volume of herniated orbital content were measured with 3D image processing software. Statistical analysis was performed to evaluate the correlations between the 2D and 3D parameters. Results Varying degrees of positive correlation were found between the 2D extent of the orbital defects and the 3D herniated orbital volume in both groups (Pearson correlation coefficient, 0.568-0.788; $R^2=32.2%-62.1%$). Conclusions Both the calculated and measured 2D extent of the orbital defects showed a positive correlation with the 3D herniated orbital volume in orbital wall fractures. However, a relatively large volume of herniation (>$0.9cm^3$) occurred not infrequently despite the presence of a small orbital defect (<$1.9cm^2$). Therefore, estimating the 3D volume of the herniated content in addition to the 2D orbital defect would be helpful for determining whether surgery is indicated and ensuring adequate surgical outcomes.

• International Journal of Highway Engineering
• /
• v.14 no.3
• /
• pp.173-182
• /
• 2012

Entry and exits of the rest area are sections where designed speed can be rapidly change and also a weak traffic safety section. In addition, two tasks can be performed simultaneously at entry of the rest area, particularly searching for deceleration and parking spaces/parking sides etc. Thus, design criteria is required in order to procure the stability of accessed vehicle. In case of Korea, geometric structure design criteria of entry facilities, such as toll-gate, interchange, junction etc was established. However there are no presence in a detailed standards for geometric structure of the rest area which affiliated road facilities. In this study, Derive problems in regards to the entry of geometric structure of resting areas by utilizing a sight survey and an investigation research of traffic accidents. The survey was targeting 135 general service areas. After Classifying the design section of resting areas' entry as well as derive design elements on each section, a speed measurement by targeting entry of rest areas and car behavior surveys were performed, then each element's minimum standard was derived through the analyses. According to the speeds at the starting/end point of entrance connector road, the minimum length of the entrance connector road is decided as 40m using Slowing-down length formula and based on the driving pattern, the range of the junction setting angle of the entrance connector road is defined as $12^{\circ}{\sim}17^{\circ}$. Suggest improvement plans for existing rest areas that can be applied realistically. This should be corresponded to the standards of entry and exit of developed rest areas.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.23 no.3
• /
• pp.554-561
• /
• 2009

Soyangin-Hyeongbangpaedok-san(SHBPDS) is a herbal formula used for the common cold or upper respiratory illness. In order to investigate the effect of SHBPDS, mice were orally administered with SHBPDS alcohol extract for 7 days followed by intravenous anti-CD3 injection. In addition, splenocytes and CD4 T cells were cultured with SHBPDS in response to anti-CD3 in vitro and cytokines and transcription factors were evaluated. In vivo treatment with SHBPDS significantly augmented the expressions of the percentage of CD4 T cells and CD 69, an indicator of early T cell activation. Serum levels of IL-4 were significantly increased but those of IFN-${\gamma}$ and IL-2 did not reach statistical significance. The expressions of IFN-${\gamma}$ and T-bet mRNA were significantly downregulated in SHBPDS treated mice while those of IL-4 and C-Maf were significantly upregulated. In vitro stimulation of splenocytes and CD4 T cells by SHBPDS resulted in a reduction in IFN-${\gamma}$ secretion and STAT4 activity. The IL-4 releases from both cells were slightly reduced, but STAT6 activity was rather increased. In conclusion, SHBPDS exerted an inhibition in the expression of IFN-${\gamma}$, T-bet and STAT4 while IL-4, C-Maf and STAT6 were increased. Further studies are required to examine its pharmacological effects using more appropriate animal experiments.