• Journal of the Korean Society of Marine Environment & Safety
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• v.17 no.3
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• pp.257-264
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• 2011

On April 20, 2010, semi-submersible offshore drilling unit Deepwater Horizon was exploded and sank, and 4.9 million barrels(about 778 thousand tons) of crude oil was spilled into the Gulf of Mexico. As more than one year has been passed since the incident, a lot of investigation reports and lessons learned have been made public and also a lot more will be released soon. This paper studies the final report of the National Commission on "the BP Deepwater Horizon Oil Spill and Offshore Drilling", which was organized by the executive directive of U.S. President Barack Obama, and the interim report of Joint Investigation team of U.S. Coast Guard and BOEMRE of "Report of Investigation into the Circumstances Surrounding the Explosion, Fire, Sinking and Loss of Eleven Members Aboard the Mobile Offshore Drilling Unit Deepwater Horizon". The review is focused on the response to the oil spill. And the paper suggests how to improve national marine pollution response policy. In the paper, the Korean governments is suggested to reinforce the capability for instructing and supervising the responsible party's source control measures, to review how to introduce in-situ burning and vessel of opportunity program into our country, and to continue monitoring on the progress of developments of R&D projects related to oil spill response in the U.S..

• Proceedings of the KOR-BRONCHOESO Conference
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• 1991.06a
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• pp.11-12
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• 1991

편측 성대마비의 음성개선을 위하여 현재까지 알려진 치료방법은 teflon 또는 silicone 주입술, 외과적 성대 내전술, 갑상연골 성형술, 신경재식술, 등이 있으며, 근래까지는 Teflon 또는 Gelform 주입술이 제일 효과적인 방법이라 알려져 있으나, 이는 음의 높낮이 조절능력의 한계가 있고, 신경재식술의 결과 역시 만족스럽지 못한 경우가 많다. 따라서 저자는 발성기능의 생리학적인 측면에서, 보다 효과적인 음성개선의 방법을 찾기 위하여, 사람의 후두와 비교적 유사한 특성을 가진 개를 사용하여 실험을 하였다. 반회신경을 절단하여 편측 성대 마비를 유발한 뒤, 동측의 유일한 외전근인 후윤상피열근을 절제후 절단된 신경을 문합하여, 성대의 외전근 작용의 소실과, 발성시에 주로 작용하는 내전근만의 작용을 유도하여, 공동운동의 차단과, 내전운동의 향상을 기대하였다. 본 실험에 앞서, 임의적으로 신경을 자극시킬 수 있는 신경자극기와, 주위조직으로부터 신경만을 분리하여 자극할 수 있는 전극을 개발하여 사용하였으며, 또한 성대의 발성음을 임의대로 유발시킬 수 있는 생체 내 후두발성 모형(in vivo laryngeal phonation model)을 Moore(1987, 1988)등이 발표한 모형을 토대로 자체 개발하여 사용하였다. 실험은 13마리의 개를, 반회신경 절단군(3 마리), 반회신경 절단 및 후윤상피 열근 절제군(3 마리), 후윤상피열근 절제군(3 마리), 반회신경 문합 및 후윤상피 열근 절제군(4 마리)등으로 나누어 실험하였으며, 3 개월 후, 현수후두경, 후두 내시경, videolaryngoscopy, 신경자극 검사 등으로 성대의 내전운동 및 위치 변화의 관찰, 발성음의 음향분석 및 갑상피열근의 형태학적 변화를 관찰하여 다음과 같은 결과를 얻었다. 1. 반회신경 절단군과 반회 신경 절단 및 후윤상피열근 절제군은, 수술후 3 개월에 성대의 움직임이나 각도의 변화가 없었으며, 음향분석 결과 발성음이 아닌 잡음만이 포착되었다. 즉, 절단된 신경의 문합 없이 후윤상피열근 절제 만으로는 음성개선은 기대할 수 없었다. 2. 후윤상피열근 절제군에서는 수술 후 3 개월에 정상적인 성대의 내전운동이 관찰되었으며, 음향분석상 기본주파수 동요율 및 발성음의 강도는 약간의 증가를 보였다. 즉, 반회신경이 절단되지 않은 상태에서 후윤상피 열근 만을 절제하면, 발성음의 변화는 거의 없었다. 3. 반회신경을 절단후 문합하고 후윤상피열근을 절제한군 에서는 수술후 3 개월에, 성대의 정상적인 내전운동을 보였고, 음향분석상 수술직후에는 잡음만이 포착되었으나, 3 개월 후에는 잡음이 아닌 발성음을 들을 수 있었으며, 이 발성음의 기본주파수 및 강도는 수술전보다 감소되어 있었으나, 기본주파수 동요율은 증가되어 있었다. 즉 이 술식으로 인한 뚜렷한 발성음의 향상이 있었다. 이상의 결과로 미루어, 편측 신경 절단으로 인한 성대마비시, 절단된 신경을 봉합하고 성대의 유일한 외전근인 후윤상피열근을 절제하면, 공동운동의 차단과, 내향운동의 향상으로, 음성개선에 효과적이라고 사료되었으며, 이 방법이 편측 성대마비 환자의 효과적인 음성개선의 치료방법의 하나로 응용될 수 있으리라 생각된다.

• Journal of the Korea Society of Computer and Information
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• v.12 no.1 s.45
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• pp.161-168
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• 2007

Web attack uses structural, logical and coding error or web application rather than vulnerability to Web server itself. According to the Open Web Application Security Project (OWASP) published about ten types of the web application vulnerability to show the causes of hacking, the risk of hacking and the severity of damage are well known. The detection ability and response is important to deal with web hacking. Filtering methods like pattern matching and code modification are used for defense but these methods can not detect new types of attacks. Also though the security unit product like IDS or web application firewall can be used, these require a lot of money and efforts to operate and maintain, and security unit product is likely to generate false positive detection. In this research profiling method that attracts the structure of web application and the attributes of input parameters such as types and length is used, and by installing structural database of web application in advance it is possible that the lack of the validation of user input value check and the verification and attack detection is solved through using profiling identifier of database against illegal request. Integral security management system has been used in most institutes. Therefore even if additional unit security product is not applied, attacks against the web application will be able to be detected by showing the model, which the security monitoring log gathering agent of the integral security management system and the function of the detection of web application attack are combined.

• Communications of Mathematical Education
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• v.23 no.1
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• pp.109-128
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• 2009

This study aimed to investigate students' learning process by examining their perception process of problem structure and mathematization, and further to suggest an effective teaching and learning of mathematics to improve students' problem-solving ability. Using the qualitative research method, the researcher observed the collaborative learning of two middle school students by providing problem-posing activities of five lessons and interviewed the students during their performance. The results indicated the student with a high achievement tended to make a similar problem and a new problem where a problem structure should be found first, had a flexible approach in changing its variability of the problem because he had advanced algebraic thinking of quantitative reasoning and reversibility in dealing with making a formula, which related to developing creativity. In conclusion, it was observed that the process of problem posing required accurate understanding of problem structures, providing students an opportunity to understand elements and principles of the problem to find the relation of the problem. Teachers may use a strategy of simplifying external structure of the problem and analyzing algebraical thinking necessary to internal structure according to students' level so that students are able to recognize the problem.

• Korean Journal of Construction Engineering and Management
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• v.10 no.6
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• pp.146-153
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• 2009

The year 2008 was a hard year for Korea's construction companies. The real estate downturn resulted in halting new construction and stopping existing work, and inflation of global oil prices caused price hikes in rebar and concrete materials. As a solution to reducing the budget, the newly appointed government announced plans to increase low cost bid contracts from 10 billion to 30 billion won. When such economical and political factors negatively impact the construction market, projects based on low cost contracts are the hardest hit. Many problems already inherent in low cost bid contracts become accentuated. Consequently, this provides an opportune time to actually study and analyze the issues in these projects. This paper introduces the findings made from investigating four projects struggling to make ends meet in the year 2008. Results show that flow of cash (i.e., liquidity), or lack thereof, was the root cause which in turn was hampered by failed mechanisms for design changes, material inflation. Attributing cash flow risk to the bottom of the production structure (i.e., small business subcontractors) was also a problem within the industry. Contractors need a better way to prepare against material price fluctuations, and owners need to assist in expediting payment during times of extreme downturn.

• Journal of the Korean Institute of Gas
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• v.24 no.1
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• pp.10-16
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• 2020

In the safety control and business of liquefied petroleum gas act, LPG supply using bulk lorry of liquefied petroleum gas dealer is possible only to small storage tanks of less than 3 tons in bulk lorry less 10 tons. The government has announced plans to extend the bulk lorry supply to storage tanks of less than 10 tons, reflecting improved safety management capabilities of liquefied petroleum gas dealer. Therefore, in order to supply LPG to the storage tank stably through the bulk lorry, the technical evaluation of the existing bulk lorry LPG supply system is needed. In this study, we will investigate the status of LPG supply system in Korea through bulk lorry and investigate safe LPG supply method. First, we conducted a survey on the supply of LPG storage tanks through bulk lorry to related companies to collect basic data. Based on the results of the surveys, we will conduct field surveys to provide basic data for stable LPG supply.

• Korean Journal of Materials Research
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• v.11 no.2
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• pp.120-125
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• 2001

Generally, hydroxyapatite(HAp), zeolite, carbon molecular sieve , activated carbon and alumina are used as heavy metal ions adsorption materials. Among those adsorption materials, HAp which has good positive ion-exchange ability with metal ion, and zeolite are utilized in wastewater treatment. Most of water pollutions are caused by hazardous heavy metals ions as well as bacteria in waste water. In this study, a adsorption materials (HAP and zeolite) are ion-exchanged with a well known antimicrobial metal ions, such as $Ag^+,\;Cu^{2+},\;and\;Zn^{2+}$, in order to give a adsorption of heavy metal ions and a killing effects of bacteria. The antimicrobial effects of adsorption materials are observed using by E. Coli. The results show that there is a complete antimicrobial effect in the adsorption materials with $Ag^+$ at the concentration of $1{\times}10^{-4}$cell/$m\ell$ of E. Coli until 24 hours. However, there is not good antimicrobial effects in the adsorption materials with $Cu^{2+},\;and\;Zn^{2+}$ substitution. Feng et. al. showed the denaturation effects of silver ions which induces the condensed DNA molecules and losing their replication abilities.

• Journal of the Korea Convergence Society
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• v.9 no.11
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• pp.315-324
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• 2018

For Korean learners, writing is a harder part than any other areas in Korean languages. But in the future, the ability to organize and write systematically is essential for future koran languages learners to take classes, do assignments and presentations at school, and then adapt to job situations. Therefore, there is a need to devise a direction for this. In general, writing characteristics are viewed in many ways, including writing productivity, writing complexity, and writing errors. Accordingly, the study provided drawings and A4 paper for Vietnamese Korean learners, Chinese Korean learners, and Korean university students, before writing freely. Based on the their writing results, we looked at syntax factors (total C-units, total number of words), syntax complexity (number of words per C-unit and clause density), and writing errors (postposition, spell errors, and connective suffix, space errors) According to the study, Vietnamese and Chinese Korean language learners showed significantly lower syntax productivity and complexity than Korean university students, and showed more writing errors than Korean students in postposition and clause density. Based on the results of the study, we discussed writing guidelines for Korean languages learners. However, this study did not validate the differences in writing characteristics according to the Korean language level and length of residences for the study subjects. Therefore, it is necessary to consider this in future research.

• KIPS Transactions on Software and Data Engineering
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• v.7 no.12
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• pp.485-496
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• 2018

So far, the deep learning, a field of artificial intelligence, has achieved remarkable results in solving problems from unstructured data. However, it is difficult to comprehensively judge situations like humans, and did not reach the level of intelligence that deduced their relations and predicted the next situation. Recently, deep neural networks show that artificial intelligence can possess powerful relational reasoning that is core intellectual ability of human being. In this paper, to analyze and observe the performance of Relation Networks (RN) among the neural networks for relational reasoning, two types of RN-based deep neural network models were constructed and compared with the baseline model. One is a visual question answering RN model using Sort-of-CLEVR and the other is a text-based question answering RN model using bAbI task. In order to maximize the performance of the RN-based model, various performance improvement experiments such as hyper parameters tuning have been proposed and performed. The effectiveness of the proposed performance improvement methods has been verified by applying to the visual QA RN model and the text-based QA RN model, and the new domain model using the dialogue-based LL dataset. As a result of the various experiments, it is found that the initial learning rate is a key factor in determining the performance of the model in both types of RN models. We have observed that the optimal initial learning rate setting found by the proposed random search method can improve the performance of the model up to 99.8%.

• Journal of Korea Technology Innovation Society
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• v.22 no.2
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• pp.159-185
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• 2019

Chemical industry, as one of the basis industries of the country, is characterized by converged high-end technology and large scale capital investment. In 2018, the government announced "The Strategy for Chemical Industry Development" with the vision of 'An Upgrade to the Advanced Chemical Industry'. In the meantime, the advanced chemical industry in Korea has been developed not by its own R&D, but by the upgrading of technologies and processes through the technology transfer from developed countries. The method of technology transfer was mainly achieved with international joint ventures (hereafter IJV) linked with technology transferors from developed countries. As it is necessary to grasp the determinants of the technology transfer and their importance to promote the transfers through IJVs, this relative importance analysis study was conducted by using the method of quantifying experts' opinions (AHP) on the determinants of the technology transfer of both parties. As a result of the analysis, in the Hierarchy1(PEST factors), the technology transferees focus on economic factors such as 'profitability of technology transfer' and 'cost efficiency', while technology transferors considered technical factors such as 'operational excellence (abilities to continuously improve technology process)'. In addition, transferors and transferees have different priorities for technology transfer determinants in all areas of Hierarchy 2 (sub-determinants). This suggests that Korean government or enterprise should shift the policy direction toward 'technology-oriented' when they promote advanced-technology transfer through IJVs.