• Journal of Dental Rehabilitation and Applied Science
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• v.33 no.2
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• pp.114-118
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• 2017

Purpose: The aim of this study was to investigate the effects of a titanium component for the zirconia abutment in the internal connection implant system on screw loosening under thermocycling conditions. Materials and Methods: Internal connection titanium abutments and external connection zirconia abutments with titanium sockets were connected respectively to screw-shaped internal connection type titanium implants with 30 Ncm tightening. These implant-screw-abutment assemblies were divided into two groups of five specimens each; titanium abutments as control and zirconia abutments with titanium sockets as experimental group. The specimens were subjected to 2,000 thermocycles in water baths at $5^{\circ}C$ and $55^{\circ}C$, with 60 seconds of immersion at each temperature. The removal torque values (RTVs) of the abutment screws of the specimen were measured before and after thermocycling. RTVs pre- and post-thermocycling were investigated in statistics. Results: There was not screw loosening identified by tactile and visual inspection in any of the specimens during or after thermocycling. The mean RTV difference for the control group and the experimental group were $-1.34{\pm}2.53Ncm$ and $-1.26{\pm}2.06Ncm$, respectively. Statistical analysis using an independent t-test revealed that no significant differences were found in the mean RTV difference of the groups (P > 0.05). Conclusion: Within the limitations of this in vitro study, the titanium socket for the zirconia abutment did not show a significant effect on screw loosening under thermal stress compared to the titanium abutment in the internal connection implant.

• Journal of radiological science and technology
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• v.37 no.1
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• pp.1-6
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• 2014

Breast shooting performance management and quality control of the generator is applied to the amount of current IEC(International Electrotechnical Commission) 60601-2-45 tube voltage and tube current are based on standards that were proposed in the analysis of the test results were as follows. Tube voltage according to the value of the standard deviation by year of manufacture from 2001 to 2010 as a 42-3.15 showed the most significant, according to the year of manufacture by tube amperage value of the standard deviation to 6.38 in the pre-2000 showed the most significant, manufactured after 2011 the standard deviation of the devices, the PAE(Percent Average Error) was relatively low. This latest generation device was manufactured in the breast of the tube voltage and tube diagnosed shooting the correct amount of current to maintain the performance that can be seen. The results of this study as the basis for radiography diagnosed breast caused by using the device's performance and maintain quality control, so the current Food and Drug Administration "about the safety of diagnostic radiation generator rule" specified in the test cycle during three years of self-inspection radiation on a radiation generating device ensure safety and performance of the device using a coherent X-ray(constancy) by two ultimately able to keep the radiation dose to the public to reduce the expected effect is expected.

• Journal of Conservation Science
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• v.33 no.6
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• pp.443-456
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• 2017

The Geumran-gasa (Kasaya) and Jangsam of the monk Samyeong are historical relics and were designated as object No.29, a Buddhist costume of the Joseon Dynasty, by the National Folklore Cultural Heritage, in 1973. In 1984, after being treated for the purposes of washing and preserving the shape of the garments, the object was kept in the Temple Museum of Pyochungsa, as their holding institution. However, regular inspection conducted by the Cultural Heritage Administration in 2013 determined the need for a re-treatment. The Geumran-gasa had been originally made with 25 strips, but it had been separated into two parts and many pieces were lost. A part of the collar in the Jangsam was lost as well. Therefore, both relics needed to be restored. The re-treatment process involved pre-investigation, washing, reinforcement fabric dyeing, restoration, and fumigation. In particular, we focused on reinforcing the damaged parts and restoring the missing parts by applying advanced materials and methods in order to restore the original form as much as possible. This conservation is the result of the re-treatment of the cultural properties by replacing the old material used in past treatments and applying advanced methods under the basic principle of reversibility in conservation treatment.

• Journal of dental hygiene science
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• v.16 no.3
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• pp.249-255
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• 2016

The Ministry of Health and Welfare in Korea has enforced the oral health promotion program for elderly in Korea. There are the denture delivery program and the fluoride application-scaling program for elderly. Donggu Public Health Center in Daejeon has delivered the fluoride application-scaling program for elderly since the demonstration project in 2009. The official dental hygienists had a prior consultation with Dong-gu branch of Korean Senior Citizens Association in Daejeon. We expanded the program through government office, welfare centers, and nursing homes. The participants were satisfied with the public relations (95.2%), scaling (99.7%), fluoride application (91.5%), toothbrushing education (98.6%), and denture cleaning education (96.6%). After a medial accident with persistent bleeding, the pre-inspection survey about systemic disease and medication was reinforced. The official dental hygienists have agonized over the low participation of the low-income group and the overlap benefit with health insurance benefit of scaling. We suggested it be needed the assessment of the public oral health program to overlap with health insurance benefit.

• Journal of Korean Elementary Science Education
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• v.29 no.4
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• pp.552-566
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• 2010

This paper is an in-depth case study to analyze integrated elementary science lesson planning and practical teaching by two teachers at an urban elementary schools. One is an experienced teacher and the other is a beginning teacher. For this study, researchers asked teachers to design 5 stages of lesson planning after sharing basic theories about the integrated science education. The first of the 5 lesson planning stages is curriculum analysis and choice of integrated science topic. The second stage is constructing the frame of integrated science lesson contents, and the third is drawing a diagram of the integrated science lesson development. The fourth stage is making a table of lesson plans, and the last stage is writing integrated science lesson plans. Then, the teachers implemented the lessons they created. They taught students one unit of science which is composed of 8 lessons. Difficulties that teachers meet during designing plans and integrated science class were analyzed. 5 staged lesson planning, video transcriptions, teacher interview about lesson planning and teaching, researchers' checklists, reports of inspection classes, teachers' self evaluation, and students interviews were used for this study. One of the significant results of this study is that both experienced and beginning teachers had many difficulties in deciding on time to teach and contents of science and other subjects, as well as selection and organization of whole topics of integrated science teaching. The beginning teacher especially had greater issues with developing definite teaching-learning strategy to conduct thoughts and views for integrated science at the whole unit and each lesson. However, the experienced teacher was using various teaching-learning strategies by utilizing integrated science teaching professionalism to develop students' integrated thinking ability during the instruction of other subjects. The outcomes of this study are that both teachers could deeply understand the need and value of integrated science education at the elementary school through planning and teaching 8 lessons, and that they could have self-confidence with development of teaching professionalism for integrated science teaching. It may be possible that this study could help the development of pre- and in-service program for improvement of integrated science teaching professionalism for elementary school teacher.

• 한국환경농학회:학술대회논문집
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• 2009.07a
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• pp.3-18
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• 2009

It is difficult for consumers to satisfy high safety request with post-management method such as inspection and surveillance, as various changes in-and-out of the country associated with food safety. In terms of food safety problems related to foods, it is crucial to recognize public health and consumer protection and construct pre-preventive Food Control System. A joint committee, FAO/WHO made the following consultations to the National Food Safety System. ${\circ}$ Approach entirely from farm to table ${\circ}$ Get ready for Risk Analysis System ${\circ}$ Secure transparency ${\circ}$ Establish the optimal policy by evaluating the effect of regulation When it comes to summarizing the consultation, it would be accumulated as two key words; "Efficiency" and "Credibility". Whereas the problem of efficiency focuses on precaution rather than post-management, it requires policy option to maximize consumer's benefit by evaluating the cost for the Food Safety Management and its benefit. Also, analyzing risk's character and amount, demanding an optimal means, and introducing scientific analysis system put much value on the stakeholder's communications are procedure's security which can satisfy both "Efficiency" and "Credibility" simultaneously. Especially, it is emphasized here that Risk Assessment need to be separated from Risk Management. This action is a valid means of credibility security throughout improving transparency. A number of nations and organizations have reformed the method of food management passing through reflection and examination of the prior National Food Safety Management since BSE occurred in Britain, 1996. FSA; Food Standard Agency, AFFSA, EFSA, BfR, and FSC are Risk Assessment Organization functionally separated from Risk Management Organization, JECFA, JMCFA, JMPR, JEMRA in Codex charge Risk Assessment internationally. In case of advanced countries excluding several those such as The U.S. and so forth, though these Risk Assessment Organizations are either separated functionally within Risk Management Organization or operated as apart organ, common factors are in which it has independence as Science Base. While securing independence of Risk Assessment Function, it is a tendency Risk Management should be functionally unified into efficiency as well. Though Germany constructs integral Risk Management System of diverse ways according to social and political conditions of each country such as GFOCP, DVFA, SNFA, CFIS and AQIS, there is a key word in the center, "Securing efficiency of Food Safety Management". However our nation has a representative plural；diversified system with The U.S., we took a step forward for unification as empowering policy's generalization；adjustment and Risk Assessment Function by means of enacting the "Food Safety Fundamental Law" in 2008 and establishing the "Food Safety Policy Commission" with private and governmental sectors in the Prime Minister's office. Even though the unification of Risk Management hereby increased, there is the lack of strengthening function of Risk Assessment and securing independence. It needs to be required for the professional committee in Food Safety Policy Commission to develop as a exclusive office of Risk Assessment by separating from a policy decision. Administrative Branches should reinforce feeble functions such as fundamental investigation；research for carrying out Risk Assessment with securing efficiency throughout reassessment of prior Risk Management Means.

• Journal of Science and Technology Studies
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• v.18 no.1
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• pp.5-62
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• 2018

Over the last 10 years, the fight against occupational diseases of semiconductor workers led by SHARPS(the Supporters for the Health And Rights of People in the Semiconductor industry, NGO) has accomplished considerable achievements, especially in the legal and institutional aspects. First, the court and the government accepted the claims that 24 injured workers respectively filed, recognizing their 10 types of diseases as occupational illness. The court not only expanded the list of work places and diseases that it recognized, but also presented more progressive logic of recognition. The most remarkable achievement among them is the case ruled by the Supreme court in July, 2017. In terms of 'worker's right to know', which is the most important factor in preventing occupational diseases, there have been significant legislative bills, court rulings and government guidelines. The revised bill of the Industrial Safety and Health Act to strengthen workers' rights to know and to introduce the pre-review system on trade secret is currently under review by the National Assembly. The court recently ruled that the government should disclose its inspection results on safety and health management at semiconductor factories. The ministry of labor has drawn up internal guidelines to more actively open its safety and health data to public. This study looks over recent developments in such rulings, bills and guidelines and then, analyzes their implications, laying the groundwork for future actions for worker health in the electronic industry.

• Smart Structures and Systems
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• v.21 no.5
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• pp.687-694
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• 2018

The problem of wheel tread defects has become a major challenge for the health management of high-speed rail as a wheel defect with small radius deviation may suffice to give rise to severe damage on both the train bogie components and the track structure when a train runs at high speeds. It is thus highly desirable to detect the defects soon after their occurrences and then conduct wheel turning for the defective wheelsets. Online wheel condition monitoring using wheel impact load detector (WILD) can be an effective solution, since it can assess the wheel condition and detect potential defects during train passage. This study aims to develop an FBG-based track-side wheel condition monitoring method for the detection of wheel tread defects. The track-side sensing system uses two FBG strain gauge arrays mounted on the rail foot, measuring the dynamic strains of the paired rails excited by passing wheelsets. Each FBG array has a length of about 3 m, slightly longer than the wheel circumference to ensure a full coverage for the detection of any potential defect on the tread. A defect detection algorithm is developed for using the online-monitored rail responses to identify the potential wheel tread defects. This algorithm consists of three steps: 1) strain data pre-processing by using a data smoothing technique to remove the trends; 2) diagnosis of novel responses by outlier analysis for the normalized data; and 3) local defect identification by a refined analysis on the novel responses extracted in Step 2. To verify the proposed method, a field test was conducted using a test train incorporating defective wheels. The train ran at different speeds on an instrumented track with the purpose of wheel condition monitoring. By using the proposed method to process the monitoring data, all the defects were identified and the results agreed well with those from the static inspection of the wheelsets in the depot. A comparison is also drawn for the detection accuracy under different running speeds of the test train, and the results show that the proposed method can achieve a satisfactory accuracy in wheel defect detection when the train runs at a speed higher than 30 kph. Some minor defects with a depth of 0.05 mm~0.06 mm are also successfully detected.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.321-327
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• 2020

Engine oil leaks comprise the largest percentage of the major quality problems that have occurred during the engine production process for military land system equipment over the last two years. To minimize this, it is essential to understand the root cause of the engine oil leakage and perceive the more common leakage area, as well as reduce the quality costs of pre-identification for leaks in the engine assembly process and single items. Therefore, in this study, the mass production quality of engines installed and operated in power equipment was improved by visualizing the engine oil leakage injected with the fluorescent dye and increasing the identification of the engine oil leak phenomenon. For this reason, the possibility of substituting the engine oil was considered and the engine oil was injected with the fluorescent dye. The maintenance was improved by reforming the engine oil injection process and leakage inspection process. Finally, these results suggest that the quality costs between mass production processes can be minimized by ensuring the reliability of military engines by reducing the user's complaints and improving the quality control capabilities of engine manufacturers.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.46 no.2
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• pp.65-77
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• 2009

This paper proposes fast image processing algorithms using SSE (Streaming SIMD Extensions) instructions. The CPU's supporting SSE instructions have 128bit XMM registers; data included in these registers are processed at the same time with the SIMD (Single Instruction Multiple Data) mode. This paper develops new SIMD image processing algorithms for Mean filter, Sobel horizontal edge detector, and Morphological erosion operation which are most widely used in automated optical inspection systems and compares their processing times. In order to objectively evaluate the processing time, the developed algorithms are compared with OpenCV 1.0 operated in SISD (Single Instruction Single Data) mode, Intel's IPP 5.2 and MIL 8.0 which are fast image processing libraries supporting SIMD mode. The experimental result shows that the proposed algorithms on average are 8 times faster than the SISD mode image processing library and 1.4 times faster than the SIMD fast image processing libraries. The proposed algorithms demonstrate their applicability to practical image processing systems at high speed without commercial image processing libraries or additional hardwares.