• School Mathematics
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• v.17 no.1
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• pp.35-46
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• 2015

In this paper, the teaching contents for angle and measure of an angle in elementary mathematics textbook between Korea and Japan were compared. From this comparison, the following five suggestions were presented as implications to improve the teaching contents for angle and measure of an angle in elementary mathematics textbook in Korea. First, it is necessary to reconsider the way of the definition of angle. There is no use of half line in elementary mathematics, except when to define angle, and the way to define angle and the way to define right angle are not consistent. Second, considering to associate the turning of plane geometrical figures to the $90^{\circ}$, $180^{\circ}$, $270^{\circ}$, $360^{\circ}$ is necessary, and associating them is connected to dealing with point-symmetrical shapes in the fifth grade. Third, there is a need to deal with "the measures of angles are same." in comparing angles. This is possible by superimposing two angles in comparing the measures of them. Fourthly, it is necessary to consider the introduction of the rotational angle. Dealing with the $360^{\circ}$ as the rotational angle is related to explaining that the sum of measures of interior angles in quadrangle is $360^{\circ}$. Fifth, it is necessary to be connected with middle school mathematics curriculum. The term 'straight angle' is used in middle school, and to obtain the sum of the measures of the interior angles of a regular polygon is the contents to be dealt with in middle school.

• Journal of the Korea Computer Industry Society
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• v.5 no.9
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• pp.1101-1110
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• 2004

In the first quarter of 2004, there were about 1 billion 348 million mobile phone users worldwide with a penetration rate of only 29%. Korea ranks among the highest in the use of mobile communication, having over 36 million mobile phone subscribers with a mobile phone penetration rate of 75% as of May 2004. Since the introduction of wireless Internet service in May 1999, the number of subscribers rose to 34.5 million with 95.3% of the total mobile phone subscribers using wireless Internet services in May 2004, largely due to continued investments by telecommunication service providers, improvement of mobile handsets (color and digital camera phones) and implementation of policies on mobile number portability. In the Korean wireless Internet market, there are many user complaints since the service providers are competing with each other through TV commercial sales and phone discounts rather than improving their call quality, services and billing systems. therefore there is a growing need to improve the billing systems through means such as the implementation of reasonable payment plans according to consumer use, development of a wireless Internet billing system that can predict the number of users and establishment of pricing standards for controlled data (head, tail, etc...) as well as menu information by testing the texts. multimedia, video and other types of content provided by the three major mobile communication companies. The purpose of this study is to promote wireless Internet services and protect user rights by proposing a reasonable way to improve the billing systems for wireless Internet services after conducting a comparative analysis of file size and billing data of each of the service providers through a verification test on a packet billing system for wireless Internet services.

• KIPS Transactions on Software and Data Engineering
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• v.6 no.7
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• pp.371-378
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• 2017

Recently, with the spread of smart device and the introduction of web services, the data is rapidly increasing online, and it is utilized in various fields. In particular, the emergence of social media in the big data field has led to a rapid increase in the amount of unstructured data. In order to extract meaningful information from such unstructured data, interest in big data technology has increased in various fields. Big data is becoming a key resource in many areas. Big data's prospects for the future are positive, but concerns about data breaches and privacy are constantly being addressed. On this subject of big data, where positive and negative views coexist, the research of analyzing people's opinions currently lack. In this study, we compared the changes in peoples perception on big data based on unstructured data collected from the social media using a text mining. As a results, yearly keywords for domestic big data, declining positive opinions, and increasing negative opinions were observed. Based on these results, we could predict the flow of domestic big data.

• The Journal of the Korea Contents Association
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• v.7 no.10
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• pp.311-320
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• 2007

This study is to analyze the present condition of internal dance troupes' web sites contents and through this study, we aim at suggesting beneficial plans not only for constructing better web sites and contents for national dance troupes but also for contributing to the development of national dance troupes. In order to achieve this study's object, we selected eight dance troupes that run their own web sites and examined their contents. the conclusions are as following. First, among internal professional dance troupes, Korea National Ballet, Seoul Ballet Theatre and Universal Ballet Company offer the best contents at their home pages and they have the most lively community concerned activities at their internet web sites. Second as for the web sites of municipal(provincial) dance troupes, those of Gyeonggi provincial dance troupe, Daejeon municipal dance troupe, Busan municipal dance troupe, Seoul municipal dance troupe Incheon municipal dance troupe have lots of contents briskly carried on, but those of the others need complementary measures. Third, Seoul ballet theatre and Universal Ballet Company offer lots of information about their activities to satisfy their customers and make the maximum use for public relations ; performance news, the introduction of their members, the story of ballet press reviews, new letters. On the other hand, at the web sites of Metropolitan Dance Theater Provincial Dance Company, there are much fewer contents about their activities which doesn't lead customers to visit their webs.

• Korean Security Journal
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• no.59
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• pp.189-215
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• 2019

As modern society has become specialised and complex in all areas of politics, economy and society, it has reached a point where it is difficult to control crime with the general public power. Private security, which began to fluctuate after the 19th century, has expanded its scope to subsidise public power in various areas, sometimes beyond public power. Among these private security activities, the private investigate system has long been used to provide private investigate services that are safe from personal human rights protection and crimes. This study investigate the private investigation system in the United Kingdom and South Korea focusing on the missing person investigation system by using the qualitative content analysis of research methods. First, the results of the qualitative content analysis are described through methods such as literature reviews and interviews on how the British private investigation system and the missing persons search system are implemented. Next, the results of the content analysis are presented through the methods of literature reviews and questionnaires on how the implementation of the civilian survey in Korea and the search for missing people is proceeding. It is a very important field in both countries, and there is a very limited study, especially from a Korean perspective. Therefore, it is expected that this study will not only facilitate discussions for the successful legalisation of the private research system, but also provides a basic foundation for future research. The study of the private research system should be ongoing and periodic, not temporary. In addition, in order to introduce Korea's private survey system, the private investigation system should be developed by discovering the problems of the Private Investigation Law mentioned in this study and collecting opinions from citizens, academics and related institutions. The introduction of the private investigation system requires the connection of the efforts and interests of citizens, academia and related institutions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.2
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• pp.249-254
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• 2013

As part of a study on insects as food, the nutritional and harmful components in the mealworm (Tenebrio molitor) were analyzed. In addition, due to a recent introduction of live Chinese mealworms in the Korean market, components between Korean and Chinese mealworms were compared. Analysis of general composition (moisture, crude protein, crude fat, crude ash, crude fiber, and carbohydrates) showed that crude protein (50.32~52.79%) was abundant in both Korean and Chinese mealworm powders, with the protein content in the Chinese mealworm powder higher than that in the Korean mealworm powder by 2.67%. The amino acid compositions were similar, but the fatty acid compositions differed in the Korean and Chinese mealworm powders. The unsaturated fatty acid contents were 76.80~80.55% of the total fatty acid content in the mealworms. The linoleic acid contents in the Korean and Chinese mealworms were $20.8{\pm}1.1%$ and $34.69{\pm}1.9%$; the linolenic acid contents were 0.47% and 1.31%; and the oleic acid contents were $51.40{\pm}0.9%$ and $40.20{\pm}1.5%$, respectively. With respect to harmful components, such as heavy metals and bacteria that cause food poisoning, bacteria such as Escherichia coli O157:H7 and Salmonella spp. were not detected in both Korean and Chinese mealworms, and the mercury content was below the standard values for common foods (Korea, 0.03 mg/kg; China, 0.08 mg/kg).

• Korean Journal of Construction Engineering and Management
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• v.11 no.2
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• pp.54-63
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• 2010

Domestic construction companies suffer from the difficulty in financing in the wake of economic slump at home and abroad. In the periods of this economic slump, which hit the nation REITs, the facilitator of fluid financing and the stimulating of construction economic, has increasingly been expanded since its introduction in 2001. But, REITs relatively falls behinds any other nations, in terms of its growth speed and marketing volume. The purpose of this research thesis is to suggest the method for composing a portfolio using Markowitz portfolio selection models for stimulating REITs. Main contents are as follows. First, the thesis made the comparative analysis on profit increase in REITs investment in application of models by Markowitz and REITs derivatives from 2007/07/03 to 2008/07/21 during investment analysis periods. The result showed that total profits by Markowitz model amounted to about 10 percent higher than average profits of REITs derivatives. Second, this thesis made the analysis on sensitivity of data-gathering and portfolio change periods of the existing profits, in order to measure the both periods and yield optimum profits. The six month data-collecting periods of profits accounted for some 16% higher profits than profits of REITs derivatives. In case when the two week periods of portfolio change accounted for some 11% higher profits than profits of REITs derivatives.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2001.10a
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• pp.61-86
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• 2001

All cancers are caused by abnormalities in DNA sequence. Throughout life, the DNA in human cells is exposed to mutagens and suffers mistakes in replication, resulting in progressive, subtle changes in the DNA sequence in each cell. Since the development of conventional and molecular cytogenetic methods to the analysis of chromosomal aberrations in cancers, more than 1,800 recurring chromosomal breakpoints have been identified. These breakpoints and regions of nonrandom copy number changes typically point to the location of genes involved in cancer initiation and progression. With the introduction of molecular cytogenetic methodologies based on fluorescence in situ hybridization (FISH), namely, comparative genomic hybridization (CGH) and multicolor FISH (m-FISH) in carcinomas become susceptible to analysis. Conventional CGH has been widely applied for the detection of genomic imbalances in tumor cells, and used normal metaphase chromosomes as targets for the mapping of copy number changes. However, this limits the mapping of such imbalances to the resolution limit of metaphase chromosomes (usually 10 to 20 Mb). Efforts to increase this resolution have led to the "new"concept of genomic DNA chip (1 to 2 Mb), whereby the chromosomal target is replaced with cloned DNA immobilized on such as glass slides. The resulting resolution then depends on the size of the immobilized DNA fragments. We have completed the first draft of its Korean Genome Project. The project proceeded by end sequencing inserts from a library of 96,768 bacterial artificial chromosomes (BACs) containing genomic DNA fragments from Korean ethnicity. The sequenced BAC ends were then compared to the Human Genome Project′s publicly available sequence database and aligned according to known cancer gene sequences. These BAC clones were biotinylated by nick translation, hybridized to cytogenetic preparations of metaphase cells, and detected with fluorescein-conjugated avidin. Only locations of unique or low-copy Portions of the clone are identified, because high-copy interspersed repetitive sequences in the probe were suppressed by the addition of unlabelled Cotl DNA. Banding patterns were produced using DAPI. By this means, every BAC fragment has been matched to its appropriate chromosomal location. We have placed 86 (156 BAC clones) cytogenetically defined landmarks to help with the characterization of known cancer genes. Microarray techniques would be applied in CGH by replacement of metaphase chromosome to arrayed BAC confirming in oncogene and tumor suppressor gene: and an array BAC clones from the collection is used to perform a genome-wide scan for segmental aneuploidy by array-CGH. Therefore, the genomic DNA chip (arrayed BAC) will be undoubtedly provide accurate diagnosis of deletions, duplication, insertions and rearrangements of genomic material related to various human phenotypes, including neoplasias. And our tumor markers based on genetic abnormalities of cancer would be identified and contribute to the screening of the stage of cancers and/or hereditary diseases

• The Journal of the Korean bone and joint tumor society
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• v.11 no.1
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• pp.32-39
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• 2005

Introduction: Currently, F-18 fluorodeoxyglucose positron emission tomography scans (FDG-PET) has been investigated in soft tissue tumor especially for tumor detection and noninvasive grading. However, the validity and the efficacy of FDG-PET are still unclear in clinical evaluation. The purpose of this study is to determine the efficacy of FDG-PET in compared to conventional diagnostic imaging studies currently used in the soft tissue tumor. Methods: Between March 2001 and March 2002, 29 patients (sixteen males, thirteen females, mean age, 47 years; a range from 4 to 73) diagnosed with soft tissue tumor were evaluated by both conventional diagnostic imaging and FDG-PET. Valid reference test of the local lesion was the histopathologic diagnosis, which was measured in all patients. The suspecting metastasis in the imaging studies was validated by pathology or follow up imaging for at least 6 months. Each imaging diagnosis was made independently. The accuracy of each diagnostic method was evaluated. The incremental cost accuracy ratio was determined in each diagnostic method. Results: For detection of local lesion, sensitivity, specificity, and accuracy for MRI and FDGPET scans were 91%, 57%, 83% and 95%, 43%, 83% respectively. For detection of distant lesion, sensitivity, specificity, accuracy for conventional diagnostic methods and FDG-PET scans were 77%, 89%, 87% and 92%, 94%, 93% respectively. The incremental cost accuracy ratio (ICAR) of FDG-PET for detection of distant lesion was 145,000won/%. According to ICAR for each tumor grade, PET strategy is most cost-effective at high grade tumors. Conclusions: For detection of local lesion such as recurrence or remnant tumor, FDG-PET scan was not more accurate than MRI. However, It was more accurate for detection of metastatic lesion than conventional methods. For detection of high grade tumor, PET was most costeffective than for detection of lower grade tumor.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.1
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• pp.49-53
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• 2011

Introduction: This study compared the strength of osseointegration as determined by the resistance to reverse torque rotation of three different hydroxyapatite coated implants in the rabbit femur model. Materials and Methods: Three hydroxyapatite coated implants (HAPTITE), Tapered Screw-Vent (TSV) and BioTite-H - were used. A total of 40 implants were placed in the femur of 20 adult male rabbits. The animals were divided into two groups. In group A (n=10); one HAPTITE was placed into each right femur and one TSV was placed into each left femur. In group B (n=10); one HAPTITE was placed into each right femur and one BioTite-H was placed into each left femur. Five rabbits of each group were sacrificed at 4 and 8 weeks. The implants were removed by reverse torque rotation using a digital torque-measuring device. A total of 40 implants in 20 rabbits were used for the removal torque measurements. Results: In the Group A, 4 weeks after implant placement, the mean removal torque for the HAPTITE and TSV was $70.7{\pm}31.6$ N cm and $28.9{\pm}15.1$ N cm, respectively. Eight weeks after implant placement, the mean removal torque for the HAPTITE and TSV was $87.9{\pm}26.2$ N cm and $54.9{\pm}22.4$ N cm, respectively. In the Group B, 4 weeks after implant placement, the mean removal torque for the HAPTITE and BioTite-H was $58.0{\pm}29.6$ N cm and $37.7{\pm}14.1$ N cm, respectively. Eight weeks after implant placement, the mean removal torque for the HAPTITE and BioTite-H was $91.4{\pm}47.1$ N cm and $30.8{\pm}9.8$ N cm. HAPTITE showed a higher removal torque than the other implants. Conclusion: These results suggest that HAPTITE increases the strength of osseointegration significantly as determined by the resistance to reverse torque rotation.