• Journal of Mechanical Science and Technology
• /
• v.15 no.9
• /
• pp.1257-1267
• /
• 2001

For efficient mechanical system optimization, a new two-point approximation method is presented. Unlike the conventional two-point approximation methods such as TPEA, TANA, TANA-1, TANA-2 and TANA-3, this introduces the shifting level into each exponential intervening variable to avoid the lack of definition of the conventional exponential intervening variables due to zero-or negative-valued design variables. Then a new quadratic approximation whose Hessian matrix has only diagonal elements of different values is proposed in terms of these shifted exponential intervening variables. These diagonal elements are determined in a closed form that corrects the typical error in the approximate gradient of the TANA series due to the lack of definition of exponential type intervening variables and their incomplete second-order terms. Also, a correction coefficient is multiplied to the pre-determined quadratic term to match the value of approximate function with that of the previous point. Finally, in order to show the numerical performance of the proposed method, a sequential approximate optimizer is developed and applied to solve six typical design problems. These optimization results are compared with those of TANA-3. These comparisons show that the proposed method gives more efficient and reliable results than TANA-3.

• Journal of Korean Society of Water and Wastewater
• /
• v.33 no.6
• /
• pp.429-436
• /
• 2019

Since the discovery of the first artificial synthetic plastic, bakelite, polymer materials have been recognized as one of the most innovative fields of research. The plastic debris that is being piled up on the earth (called abandoned plastic litters) is now being observed everywhere on Earth, becoming an increasingly serious environmental threat. The term 'microplastics', created in 2004, now refers to plastic particles that are smaller than 5 mm, including all nano-sized plastic particles. However, there is no legal regulation, and there is still a lack of comprehensive definitions that practically include microplastic size standards. In this study, we will refer to "microplastics" as the English name, and look at how to identify these microplastics and propose new definitions that focus on their size. This study is expected to contribute to the domestic consensus on scientific definitions of microplastics.

• Journal of the Korean Society for Library and Information Science
• /
• v.48 no.2
• /
• pp.353-378
• /
• 2014

The purpose of this study is to find factors to affect on the formation of semantic relation from terminology and what is to be affected by these factors to build the database scheme of terminology dictionary by a structural definition. In this research, 826,905 keywords of 88,874 social science articles and 985,580 keywords of 125,046 humanities science articles in the KCI journals from 2007 to 2011 were collected. From collected data, subject complexity, structural hole, term frequency, occurrence pattern and an effect between the number of nodes and the number of patterns which were derived from the semantic relation of linked terms of established 'STNet' System were analyzed. The summarized results from analyzed data and network patterns are as follows. Betweenness Centrality, term frequency, and effective size affect the numbers of semantic relation node. Among these factors, betweenness centrality was the most effective and effective size. But term frequency was the least effective. Betweenness Centrality, term frequency, and effective size affect the numbers of semantic relation type. Term frequency is the most effective. Therefore, when building a terminology dictionary, factors of betweenness centrality, term frequency, effective size, and complexity of subject are needed to select term. As a result, these factors can be expected to improve the quality of terminology dictionary.

• Journal of Periodontal and Implant Science
• /
• v.44 no.1
• /
• pp.39-47
• /
• 2014

Purpose: Peri-implantitis, a clinical term describing the inflammatory process that affects the soft and hard tissues around an osseointegrated implant, may lead to peri-implant pocket formation and loss of supporting bone. However, this imprecise definition has resulted in a wide variation of the reported prevalence; ${\geq}10%$ of implants and 20% of patients over a 5- to 10-year period after implantation has been reported. The individual reporting of bone loss, bleeding on probing, pocket probing depth and inconsistent recording of results has led to this variation in the prevalence. Thus, a specific definition of peri-implantitis is needed. This paper describes the vast variation existing in the definition of peri-implantitis and suggests a logical way to record the degree and prevalence of the condition. The evaluation of bone loss must be made within the concept of natural physiological bony remodelling according to the initial peri-implant hard and soft tissue damage and actual definitive load of the implant. Therefore, the reason for bone loss must be determined as either a result of the individual osseous remodelling process or a response to infection. Methods: The most current Papers and Consensus of Opinion describing peri-implantitis are presented to illustrate the dilemma that periodontologists and implant surgeons are faced with when diagnosing the degree of the disease process and the necessary treatment regime that will be required. Results: The treatment of peri-implantitis should be determined by its severity. A case of advanced peri-implantitis is at risk of extreme implant exposure that results in a loss of soft tissue morphology and keratinized gingival tissue. Conclusions: Loss of bone at the implant surface may lead to loss of bone at any adjacent natural teeth or implants. Thus, if early detection of peri-implantitis has not occurred and the disease process progresses to advanced peri-implantitis, the compromised hard and soft tissues will require extensive, skill-sensitive regenerative procedures, including implantotomy, established periodontal regenerative techniques and alternative osteotomy sites.

• Journal of radiological science and technology
• /
• v.44 no.5
• /
• pp.545-554
• /
• 2021

According to the changes of the medical environment of the times, it is necessary to discuss the issues of the doctor's medical guidance and to conduct continuous research so that alternatives can be prepared systematically. Furthermore, in order to enhance the professionalism of radiological technologists and to develop the medical technician system, the new Radiological Technologist Independent Act has been established, which contains the overall contents of the scope of work, professional qualifications, and specialized education of radiological technologists, and provides quality medical services to patients through professional procedures and treatment. In order to increase the level of medical care, the purpose, definition, mission, role, and scope of work specified in the Medical Act, Medical Service Technologists, etc. Act, the Enforcement Decree, and the Enforcement Rules were variously analyzed and new directions were presented. First, the definition of a medical technician should use a generic term so that the factors of conflict and prejudice could be resolved. Second, change the doctor's guide to doctor's prescription; and then legislate the authority to sign and write medical records after examination by radiological technologists, thereby prohibiting unlicensed technicians that seriously endanger patient safety. Third, an accurate definition of radiological technologists' roles should be established; not only selection and management of radiological technologists' work but also procedures and treatment for each radiology field should be specified to suit the current medical system. Fourth, a professional radiological technologists' qualification system and a specialized education system should be established in order to secure human resources that could provide patients trust in procedures and treatment based on professional knowledge and experience in the field of radiology. Fifth, the Education and Evaluation Institute should be operated in Korea education system to educate the professional knowledge and competency for students. In addition, it is necessary to in-depth analysis of foreign cases could be applied to the medical system and education system in Korea; it could strive to nurture systematic human resources.

• Corrosion Science and Technology
• /
• v.4 no.5
• /
• pp.201-206
• /
• 2005

Starting with the meaning of the word quality, diverse concepts connoted by the term are examined. Instead of a bathtub curve, the desirable shape of a failure rate covering the entire life of a good product, which might be called hockey-stick line, is introduced. From the hockey-stick line and the definition of reliability, two measurements are extracted. The terms r-reliability (failure rate) and durability (product life) are explained. The conceptual analysis of failure mechanics explains that reliability technology pertains to design area. The desirable shape of hazard rate curve of electronic items, hockey-stick line, clarifies that Mean-Time-to-failure (MTTF) as the inverse of failure rate can be regarded a nominal life. And Bx life, different from MTTF, is explained. Reliability relationships between components and set products are explained. Reshaped definitions of r-reliability and durability are recommended. The procedure to improve reliability and the reasons for failing to identify failure mode are clarified in order to search right solutions. And generalized Life-Stress failure model is recommended for the calculation of acceleration factor.

• Atmosphere
• /
• v.21 no.1
• /
• pp.45-55
• /
• 2011

A definition on the tropical cyclone (TC) that influenced the Korean Peninsula (KP), the KP-influence TC, is widely used in the TC communities, but its criterion is not clear mainly due to the ambiguity and subjectiveness of the term such as 'influence', which led to the inconsistent TC statistical analysis. This study suggests a definition and criterion on the TC approaching to the KP (KP-approach TC) additionally, which is more obvious and objective than the KP-influence TC. In this study, the criterion on the KP-approach TC is determined when the TC's center from the RSMC best track data encounters the box areas of $28^{\circ}N{\sim}40^{\circ}N$ and $120^{\circ}E{\sim}138^{\circ}E$. The range is chosen by finding a minimum area that includes all official KP-influence TCs except three TCs that affected the KP as a tropical depression (TD). Statistical analysis reveals that, among total 1,537 TCs that occur in the western North Pacific during 1951-2008, the KP-approach TC was 472, the KP-influence TC was 187, and the KP-landfall TC was 87. August was the month that the largest TCs approach and influence to the KP. Finally, this paper suggests to determine the KP-influence TC by the strong wind and heavy rain advisories in the KP based on the observation after the storm's passage.

• Asian Journal of Business Environment
• /
• v.4 no.4
• /
• pp.5-11
• /
• 2014

Purpose - The paper aims to study strategic enterprise resource initiative formation processes. It analyzes the process of managing the strategic resource initiative and discusses its implementation mechanism. A research model for enterprises' strategic development is proposed, which suggests a geometric interpretation for estimating a company's long-term development. Research design, data, and methodology - The analysis employs theoretical studies of modern researchers. The main models used to determine the optimal alternative business strategy are graphic interpretation and mathematical modeling. Results - The hypotheses testing demonstrates the definition of a company's strategic resource initiative and explains the-mechanism or design of its formation. The study presents a geometric prism-refraction model of practice using a strategic resource initiative. Conclusions - An enterprise's strategy could return to its initial state in case of its unexpected deviation as a result of passing through the nodal points. The proposed model allows us to evaluate business performance, its surrounding environment, and the resource management strategy, to determine the necessary scope of strategy changes necessary to bring it back to the original state.

• Journal of Korean Academy of Nursing
• /
• v.23 no.4
• /
• pp.713-725
• /
• 1993

This paper presents methodological paradigms : quantitative positivistic (logical empiricism) as the received tradition in the scientific inquiry and qualitative naturalistic (post -positivism or nataralism) as a new paradigm in the Kuhnian sense. Various kind of qualitative methods under the umbrella term, qualitative inquiry, were briefly introduced. Details on the definition, epistemology, naming of subject, field technique (participant observation and ethnographic interview) of ethnographic research method as an adequate method for studying on the unique nursing phenomena in Korean culture were done. Besides, the concept of triangulation, issues on the methododogical paradigm, a criteria for rigor of qualitative naturalistic inquiry were mentioned.

• Journal of Science Education
• /
• v.44 no.3
• /
• pp.289-299
• /
• 2020

In this study, the definition, the level of difficulty, and the certainty of the understanding of 113 astronomy terminologies from 2009 revised middle school geoscience textbooks were examined. And through further interviews, the types of students' misconceptions about astronomy terminologies and their representative terms - examples of misconceptions were analyzed. The definitions of the terms presented by the students were largely classified as correct, low-level, and incorrect understanding. And low-level understanding was subdivided into high-level definition descriptions, undifferentiated concepts, and incorrect answers were subdivided into interference by scientific misconception and lack of prior knowledge. Given that the misconceptions due to terminologies can be distinguished from the prior misconception, the misconceptions due to terminologies can be effectively prevented by changing the term itself. In addition, students were aware of the advantages and disadvantages of metaphorical terms, and the recognition of their level of understanding is expected to be a good starting point considering that recognizing their own misconceptions is the first step in correcting them. Terminologies in science education is always an important subject of discussions, striving to select the right term according to the times, and scientific terms may change. It is expected that the results of this study will be the basis for discussions on the modification of terms.