• 대한의용생체공학회:의공학회지
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• 제42권3호
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• pp.125-142
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• 2021

The POCT (point-of-care test) sensing that has been a fast-developing field is expected to be a next generation technology in health care. The POCT sensors for the detection of proteins, small molecules and especially nucleic acids have lately attracted considerable attention. According to the World Health Organization (WHO), the POCT methods are required to follow the ASSURED guidelines (Affordable, Sensitive, Specific, User- friendly, Robust and rapid, Equipment-free, Deliverable to all people who need the test). Recently, several CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) based diagnostic techniques using the sensitive gene recognition function of CRISPR have been reported. CRISPR/Cas (Cas, CRISPR associated protein) systems based detection technology is the most innovative gene analysis technology that is following the ASSURED guidelines. It is being re-emerged as a powerful diagnostic tool that can detect nucleic acids due to its characteristics that enable rapid, sensitive and specific analyses of nucleic acid. The first CRISPR-based diagnosis begins with the discovery of the additional function of Cas13a. The enzymatic cleavage occurs when the conjugate of Cas protein and CRISPR RNA (crRNA) detect a specific complementary sequence of the target sequence. Enzymatic cleavage occurs on not only the target sequence, but also all surrounding non-target single-stranded RNAs. This discovery was immediately utilized as a biosensor, and numerous sensor studies using CRISPR have been reported since then. In this review, the concept of CRISPR, the characteristics of the Cas protein required for CRISPR diagnosis, the current research trends of CRISPR diagnostic technology, and some aspects to be improved in the future are covered.

• Restorative Dentistry and Endodontics
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• 제48권2호
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• pp.16.1-16.11
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• 2023

Objectives: The aim of this study was to evaluate the influence of peak kilovoltage (kVp) and a metal artifact reduction (MAR) tool on image quality and the diagnosis of vertical root fracture (VRF) in cone-beam computed tomography (CBCT). Materials and Methods: Twenty single-rooted human teeth filled with an intracanal metal post were divided into 2 groups: control (n = 10) and VRF (n = 10). Each tooth was placed into the socket of a dry mandible, and CBCT scans were acquired using a Picasso Trio varying the kVp (70, 80, 90, or 99), and the use of MAR (with or without). The examinations were assessed by 5 examiners for the diagnosis of VRF using a 5-point scale. A subjective evaluation of the expression of artifacts was done by comparing random axial images of the studied protocols. The results of the diagnoses were analyzed using 2-way analysis of variance and the Tukey post hoc test, the subjective evaluations were compared using the Friedman test, and intra-examiner reproducibility was evaluated using the weighted kappa test (α = 5%). Results: The kVp and MAR did not influence the diagnosis of VRF (p > 0.05). According to the subjective classification, the 99 kVp protocol with MAR demonstrated the least expression of artifacts, while the 70 kVp protocol without MAR led to the most artifacts. Conclusions: Protocols with higher kVp combined with MAR improved the image quality of CBCT examinations. However, those factors did not lead to an improvement in the diagnosis of VRF.

• Steel and Composite Structures
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• 제50권3호
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• pp.347-362
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• 2024

Controlling vibrations and noise in steel box girders is important for reducing noise pollution and avoiding discomfort to residents of dwellings along bridges. The fundamental approach to solving this problem involves first identifying the main path of transmission of the vibration energy and then cutting it off by using targeted measures. However, this requires an investigation of the characteristics of flow of vibration energy in the steel box girder, whereas most studies in the area have focused on analyzing its single-point frequency response and overall vibrations. To solve this problem, this study examines the transmission of vibrations through the segments of a steel box girder when it is subjected to harmonic loads through structural intensity analysis based on standard finite element software and a post-processing code created by the authors. We identified several frequencies that dominated the vibrations of the steel box girder as well as the factors that influenced their emergence. We also assessed the contributions of a variety of vibrational waves to power flow, and the results showed that bending waves were dominant in the top plate and in-plane waves in the vertical plate of the girder. Finally, we analyzed the effects of commonly used stiffened structures and steel-concrete composite structures on the flow of vibration energy in the girder, and verified their positive impacts on energy regionalization. In addition to providing an efficient tool for the relevant analyses, the work here informs research on optimizing steel box girders to reduce vibrations and noise in them.

• 한국식생활문화학회지
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• 제25권2호
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• pp.179-188
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• 2010

In order to aide in the design of an improved menu book, which could play an important role as a marketing tool, the current version of the menu books and managers (subjects) of 295 restaurants in the Incheon area were examined. These were managers of Korean (36.3%), Western (25.8%), Japanese (14.6%), cafeteria (12.5%) and Chinese (10.8%) style restaurants. The level of service (self-evaluation, 3-point scale) was average $2.25{\pm}0.45$. The general colorings of the menu books were green (19.0%), brown (18.6%), black (17.6%), yellow (15.9%), red (13.6%) and blue (13.2%). The material of the menu book cover was mainly leather (35.9%), and the internal material was mainly coated paper (59.7%). Physically, the design was two-panel fold (38.3%), two-panel multi-page (35.6%), die style (10.2%), single panel (8.1%) and tent style (7.8%). The type sizes were unchanged in 49.9% of the menu books and in 61.7% photos were not used. 53.9% of menu books did not explain the menus, and 13.2% did not classify the items into groups. Emphasis of profit-making menus was not done in 66.8%. 51.5% of menu books were irreplaceable in parts. The emphasis of profit-making menus was less among the Korean style restaurants (p<0.001). The possibility of partial replacement of menu books was lower in both Korean and Chinese restaurants (p<0.001). The explanation of the items was lower in the Japanese restaurants (p<0.001). The classification of items into groups was lower in cafeteria (p<0.001). In cases in which there were both seasonal and event menus, the possibility of partial replacements of menu books was higher (p<0.001). Restaurants of which service level was less than ordinary were lower in the differentiation of type sizes (p<0.001), the use of photos (p<0.001), the explanation of menus (p<0.001), the classification of menus by groups (p<0.05), the emphasis of profit-making menus (p<0.001) and the possibility of partial replacement of menu books (p<0.001). If these study findings are applied to the designing of menu books, the role of the menu book as an important tool for marketing could be greatly improved.

• 유통과학연구
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• 제11권5호
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• pp.63-76
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• 2013

Purpose - For the past several decades, behavioral economics or behavioral decision theory has undergone rapid development. This study provides a critical review of the development of behavioral economics with a focus on what are deemed to be core theories in the field. Starting from the utility function proposed by Daniel Bernoulli in the 18th century, the development history of utility functions until the emergence of the prospect theory is thoroughly reviewed. Some of the experimental results violating the traditionally assumed utility function and supporting the prospect theory value function are summarized. The most representative principles of rational choice are transitivity, independence from irrelevant alternatives (IIA), and regularity. The development of behavioral economics has been triggered by finding counter-examples to these principles. Some of the choice behaviors discussed in this study as counter-examples to the traditional theories of rational choice are the St. Petersburg paradox; the Allais paradox; gambling behavior; and the various context effects including the similarity effect, attraction effect, and the compromise effect. The Elimination-by-Aspects (EBA) model, which was proposed as an explanation for the similarity effect, is discussed in detail as well. Based on the literature review and further analysis, this study summarizes the relationship between the context effects, prospect theory, and EBA model. Research design, data, and methodology - This study provides an extensive literature review on several important theories in the field of behavioral decision theory and adds some critical comments to the theories and the relationships among them. This study first reviews the development of utility functions. Daniel Bernoulli introduced the concept of utility function to solve the St. Petersburg paradox. In the mid-20th century, Herbert Simon proposed the "satisficing" heuristic and presented a value function with a shape different from traditional utility functions. This study highlights the strengths and weaknesses of several utility functions proposed until the emergence of the prospect theory value function. Results - This study posits that prospect theory and EBA model are the two most important theories in the field of behavioral decision theory. They can explain various choice behaviors that traditional utility maximization analysis has been unable to. The application of these models to various fields is further increasing nowadays. This study explains how prospect theory and the EBA model can be used to explain the context effects. Conclusions - The traditional economic theory relies on a single variable called "utility" in explaining consumer choice. However, this study argues that, in investigating consumer choice, several other variables should also be considered. These are the similarity among alternatives, an alternative's prototypicality within the category, the dominance relationship between alternatives, and the reference point in evaluating alternatives. Due to the development of behavioral economics, we are now closer to a more complete understanding of consumer choice behavior than in the past when we had only a single tool called utility.

• 한국습지학회지
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• 제18권2호
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• pp.194-200
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• 2016

도시화는 불투수면의 증가를 야기 시켜 물순환 왜곡, 도시열섬효과, 비점오염물질 유출 등의 다양한 문제를 유발한다. 이러한 환경적 영향을 저감하기 위하여 도시지역과 같은 개발 사업에서는 저영향개발(Low Impact Development, LID) 기법이 중요한 대안으로 제시되고 있다. LID 기술의 주요 기작은 토양, 여재, 미생물과 식물 상호간의 수문학적 및 환경학적 기능이 포함되며, 이 중에서 여재는 LID 시설에서의 토양 내 투수율과 저류율 확보에 있어 중요한 구성요소이다. 따라서 본 연구는 LID 시설에 다양하게 활용되고 있는 제올라이트(Zeolite), 우드칩(Woodchip), 바텀애쉬(Bottom ash), 바이오세라믹(Bioceramic) 등의 여재를 단층 또는 복층으로 구성하여 강우유출수내 오염물질 저감 효율을 평가하기 위하여 수행되었다. 실험에 사용된 모든 여재는 강우유출수에 포함된 입자상 물질과 중금속을 60% 이상 제거하는 것으로 나타났으며 여재층을 복층구조로 배치할 경우에 여재 입자간의 다양한 크기의 공극과 여재 내의 미세공극(micro-pores)을 충분히 확보할 수 있기에 입자상물질 및 중금속 저감에 효과적인 것으로 나타났다. 또한 유입수 내의 효과적인 중금속의 저감을 위해서는 중금속의 입자 및 용존성 함량비율에 따른 여재의 선정과 배치가 중요한 인자로 나타났다.

• Toxicological Research
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• 제24권4호
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• pp.273-280
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• 2008

The single intratracheal instillation (ITI) of bleomycin (BLM) is a widely used method for inducing experimental pulmonary fibrosis in rat model. In the present study, pulmonary function tests (PFTs) of tidal volume ($V_T$), minute volume ($V_M$), and respiratory frequency ($F_R$) have been applied to study their possibility as a tool to monitor the progress of BLM-induced lung injury in rat model. Rats were treated with a single ITI of BLM (2.5 mg/kg) or saline (control). Animals were euthanized at 3, 7, 14, 21, and 28 days post-ITI. Lung toxicity effects were evaluated by inflammatory cell count, lactate dehydrogenase (LDH) activity in the bronchoalveolar lavage fluid (BALF), and light microscopic examination of lung injury. The PFT parameters were measured immediately before the animals were sacrificed. BLM treatment induced significant cellular changes in BALF-increase in number of total cells, neutrophils, and lymphocytes along with sustained increase in number of macrophages compared to the controls at days 3, 7, and 14. BALF LDH level was significantly increased compared to that in the controls up to day 14. On day 3, infiltration of neutrophils was observed in the alveolar spaces. These changes developed into marked peribronchiolar and interstitial infiltration by inflammatory cells, and extensive thickening of the interalveolar septa on day 7. At 14, 21, and 28 days, mild peribronchiolar fibrosis was observed along with inflammatory cell infiltration. The results of PFT show significant consistencies compared to the results of other toxicity tests. These data demonstrate that the most suitable time point for assessing lung fibrosis in this model is 14 days post-ITI of BLM based on the observation of fibrosis at 14, 21, and 28 days. Further, the progress of lung injury can be traced by monitoring the PFT parameters of $F_R$, $V_T$, and $V_M$.

• Advances in Energy Research
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• 제1권2호
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• pp.147-163
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• 2013

The world faces several issues of energy crisis and environmental deterioration due to over-dependence on single source of which is fossil fuel. Though, fuel is needed as ingredients for industrial development and growth of any country, however the fossil fuel which is a major source of energy for this purpose has always been terrifying thus the need for alternative and renewable energy sources. The search for alternative energy sources resulted into the acceptance of a biofuel as a reliable alternative energy source. This work presents the study of optimization of process of transesterification of vegetable oil to biodiesel using NaOH as catalyst. A $2^4$ factorial design method was employed to investigate the influence of ratio of oil to methanol, temperature, NaOH concentration, and transesterification time on the yield of biodiesel from vegetable oil. Low and high levels of the key factors considered were 4:1 and 6:1 mole ratio, 30 and $60^{\circ}C$ temperatures, 0.5 and 1.0 wt% catalyst concentration, and 30 and 60 min reaction time. Results obtained revealed that oil to methanol molar ratio of 6:1, tranesetrification temperature of $60^{\circ}C$, catalyst concentration of 1.0wt % and reaction time of 30 min are the best operating conditions for the optimum yield of biofuel from vegetable oil, with optimum yield of 95.8%. Results obtained on the characterizzation of the produced biodiesel indicate that the specific gravity, cloud point, flash point, sulphur content, viscosity, diesel index, centane number, acid value, free glycerine, total glycerine and total recovery are 0.8899, 4, 13, 0.0087%, 4.83, 25, 54.6. 0.228mgKOH/g, 0.018, 0.23% and 96% respectively. Results also indicate that the qualities of the biodiesel tested for are in conformity with the set standard. A model equation was developed based on the results obtained using a statistical tool. Analysis of variance (ANOVA) of data shows that mole ratio of ground nut oil to methanol and transesterification time have the most pronounced effect on the biodiesel yield with contributions of 55.06% and 9.22% respectively. It can be inferred from the results various conducted that vegetable oil locally produced from groundnut oil can be utilized as a feedstock for biodiesel production.

• 한국응급구조학회지
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• 제12권1호
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• pp.17-26
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• 2008

Purpose : With a view to providing basic data to develop basic cardiopulmonary resuscitation education suitable for female college students, the basic cardiopulmonary resuscitation education was conducted to grasp students' knowledge, skill accuracy and the attitude change before and after the education. Methods : Convenience sampling was made on first graders(total-38 students) of K college located in K city, Chungcheongnam-do, and this was a preliminary research designed before and after choosing a single group. In terms of methods, the researchers as specified ; 1) Handed out questionnaires to students directly to make them fill in firsthand and collected the questionnaires. 2) Utilized Power Point materials based on 2005 AHA guideline and used Anne/Skill Reporter$^{(R)}$ torso produced by Leardal Inc, and Little Anne$^{(R)}$ to conduct practical education individually. 3) Asked students to give Anne/Skill Reporter$^{(R)}$ torso basic cardiopulmonary resuscitation five times with the ratio of 30:2, and then one of researchers filled in the evaluation sheet individually. 4) Evaluated the accuracy of students' ability to perform the resuscitation based on the record of Anne/Skill Reporter$^{(R)}$ integrated printer(which was the objective tool to grasp students' skills accuracy). 5) Gave out questionnaires to make students fill them in and then collected them, after completing the practical evaluation. Results : 1) In case of the attitude(confidence) about basic cardiopulmonary resuscitation, students' confidency rose from 14%(before the education) to 55.5%(after the education)- which was a positive change. 2) In case of the attitude(educational necessity) about basic cardiopulmonary resuscitation, students' confidency rose from 94.7%(before the education) to 100%(after the education)- which was a positive change. 3) As a result of the education, some female college students' scored knowledge about basic cardiopulmonary resuscitation. The average point also reached 88.95%(after the education), jump from 63.51%(before the education), which was the rise of 25.44%. 4) Regarding skill accuracy, pressure accuracy(%)($M{\pm}SD=91.37{\pm}14.16$) was higher than respiration accuracy(%)($M{\pm}SD=61.55{\pm}26.13$). Conclusion : The result showed that students' attitude(confidence, on basic cardiopulmonary resuscitation changed positively, and meaningful difference(p= .000) existed in the change of students' knowledge. Anne/Skill Reporter$^{(R)}$ performance showed that the accuracy of mouth-to-mouth resuscitation was lower than that of chest compression.

• 지구물리와물리탐사
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• 제13권1호
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• pp.40-50
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• 2010

연결성이 좋지 않은 노두, 주향 경사 등의 지질 구조선을 연결하여 지질도를 작성하는 과정은 지질학자의 주관적인 견해를 배제하기 어렵다. 따라서 이러한 지질도는 좁은 지역들에서 나타나는 노두의 복잡한 공간적 분포를 이용하여 해석하게 된다. 또한, 물리탐사 자료를 이용하여 부족한 지질구조 정보를 보완하는 연구들이 수행되고 있으나, 물리탐사 자체가 가지는 역산해의 비유일성 및 각 지질 구조간의 물성 차이에 대한 불확실성으로 인하여 많은 제한점을 갖고 있다. 이번 연구에서 제안하는 방법은 예비 지질 모델 구현에 이용될 수 있는 물리탐사 자료 해석을 통해 획득된 구조 경계 정보와 지형학 자료의 삼점 해석 결과를 이용하여 주향 경사와 같은 지질 구조 정보를 제공할 수 있다. 이를 통하여 추정된 지질 정보들이 지질 조사를 통해 획득된 정보와 결합되기 위해서는 공간 규모 측면에서의 호환 가능성이 검증되어야 하며, 검증된 자료들은 평면상의 자료로 구성되어 지질학자들이 지질도를 작성하는 과정의 초기 자료로 이용되어진다. 따라서 해석된 지질도는 추정된 지질 정보와 공간적 구조적으로 부합되어져야 한다. 이 연구에서 개발된 알고리즘은 캐나다 뉴브런즈윅주 배서스트 광산 부근 두 지역의 습곡구조에 적용하여 해석하였다.