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Introduction of Inverse Analysis Model Using Geostatistical Evolution Strategy and Estimation of Hydraulic Conductivity Distribution in Synthetic Aquifer (지구통계학적 진화전략 역산해석 기법의 소개 및 가상 대수층 수리전도도 분포 예측에의 적용)

  • Park, Eungyu
    • Economic and Environmental Geology
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    • v.53 no.6
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    • pp.703-713
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    • 2020
  • In many geological fields, including hydrogeology, it is of great importance to determine the heterogeneity of the subsurface media. This study briefly introduces the concept and theory of the method that can estimate the hydraulic properties of the media constituting the aquifer, which was recently introduced by Park (2020). After the introduction, the method was applied to the synthetic aquifer to demonstrate the practicality, from which various implications were drawn. The introduced technique uses a global optimization technique called the covariance matrix adaptation evolution strategy (CMA-ES). Conceptually, it is a methodology to characterize the aquifer heterogeneity by assimilating the groundwater level time-series data due to the imposed hydraulic stress. As a result of applying the developed technique to estimate the hydraulic conductivity of a hypothetical aquifer, it was confirmed that a total of 40000 unknown values were estimated in an affordable computational time. In addition, the results of the estimates showed a close numerical and structural similarity to the reference hydraulic conductivity field, confirming that the quality of the estimation by the proposed method is high. In this study, the developed method was applied to a limited case, but it is expected that it can be applied to a wider variety of cases through additional development of the method. The development technique has the potential to be applied not only to the field of hydrogeology, but also to various fields of geology and geophysics. Further development of the method is currently underway.

A Systematic Review of Nonpharmacological Interventions on Activities of Daily Living in Dementia (치매 환자의 일상생활 수행능력 향상을 위한 비약물 중재에 관한 체계적 고찰)

  • Koo, Seul-Gi;Park, Hae-Yean;Park, Ji-Hyuk
    • 한국노년학
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    • v.37 no.2
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    • pp.445-459
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    • 2017
  • The purpose of this study is to provide a systematic review of the nonpharmacological interventions of ADL improvement for dementia published in foreign journals for the past 10 years, and to provide general information on nonpharmacological interventions and effective intervention methods to dementia expert in clinical practice. We searched published studies in the Medline Complete, PubMed Central, and Scopus databases from January 2007 to November 2016. The main keywords used "Dementia AND (ADL OR Activities of daily living) AND Nonpharmacological interventions" and total of 9 studies were selected for analysis from 974 searched articles. The level of evidence were belonged to 3 each studies in I~III level. The mostly provided nonpharmacological interventions were exercise, the study field was variety of areas including rehabilitation(occupational therapy, physical therapy), nursing, and psychology. The Barthel Index(BI) was most frequently used assessment tools to evaluate basic activities of daily living, Cognition was most dependent variables measured with the ADL. Through this study, we provided evidence for the understanding of nonpharmacological interventions of ADL improvement for dementia. In the future, based on this study, helpful intervention needed for ADL training.

A novel power trace aligning method for power analysis attacks in mobile devices (모바일 기기에서의 전력 분석 공격을 위한 새로운 전력 신호 정렬 방법)

  • Lee, Yu-Ri;Kim, Wan-Jin;Lee, Young-Jun;Kim, Hyoung-Nam
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.21 no.1
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    • pp.153-166
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    • 2011
  • Recent trends in mobile device market whose services are rapidly expanding to provide wireless internet access are drawing people's attention to mobile security. Especially, since threats to information leakage are reaching to the critical level due to the frequent interchange of important data such as personal and financial information through wireless internet, various encryption algorithms has been developed to protect them. The encryption algorithms confront the serious threats by the appearance of side channel attack (SCA) which uses the physical leakage information such as timing, and power consumption, though the their robustness to threats is theoretically verified. Against the threats of SCA, researches including the performance and development direction of SCA should precede. Among tile SCA methods, the power analysis (PA) attack overcome this misalignment problem. The conventional methods require large computational power and they do not effectively deal with the delay changes in a power trace. To overcome the limitation of the conventional methods, we proposed a novel alignment method using peak matching. By computer simulations, we show the advantages of the proposed method compared to the conventional alignment methods.

Interpretation of the Forest Therapy Process and Effect Verification through KeyWord Analysis of Literature on Forest Therapy (산림치유 효과 검증 연구의 주요어 분석을 통한 치유 발현과정 해석)

  • Park, Kyeong-Ja;Shin, Chang-Seob;Kim, Dongsoo
    • Journal of Korean Society of Forest Science
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    • v.110 no.1
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    • pp.82-90
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    • 2021
  • In this study, the validity of the forest therapy process, in which forest activities using forest therapy factors lead to immunity promotion and health promotion, was analyzed theoretically and qualitatively to refine and systemize the forest therapy concept. Research and analysis data were collected from the websites of institutions related to forest therapy; 33 theses and 33 original research articles from 2000 to March 2020 were searched for forest therapy key words, as well as the prize winning work of the 2016 forest therapy experience essay. A word cloud was generated by frequency of nouns and adjectives and from the key words in the web pages, theses, articles, and the forest therapy experience essay. Through interpretation of word frequency, the systemic flow of forest therapy was defined. The results suggest that the source of forest therapy's power was a positive experience of the forest and an improved attitude toward nature as well as forest therapeutic factors. The therapeutic effect is maximized through the forest healing program, leading to physical and mental resilience and resistance; consequently, health and immunity are promoted. From this study, forest therapy is proposed as "a health promotion activity for the psychological, physical, and spiritual resilience of the subjects through various environmental factors of the forest, positive experiences, and attitudes toward the forest."

A Study on Rust Cleaning of Various Industrial Equipment Using Cosmetic and Food Materials (화장품과 식품 재료를 이용한 각종 산업장비 녹(rust) 세정에 관한 연구)

  • Yeom, Seok-Jae;Jung, Sundo;Oh, Eunha
    • Journal of the Korean Applied Science and Technology
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    • v.38 no.1
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    • pp.19-28
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    • 2021
  • Corrosion is the degradation of metals by reaction with the environment. It is difficult to completely remove. Corrosion proceeds rapidly after the protective barrier is destroyed, and several reactions occur that alter the composition and properties of the metal surface and local environments, such as diffusion of metal cations into the matrix, the formation of oxides, and local pH changes. The study of corrosion of steel and iron is of theoretical and practical interest and is receiving considerable attention. Acid solutions, which are widely used in industrial pickling, acid descaling, cleaning and acidification of oil wells, require the use of corrosion inhibitors to suppress corrosion attacks on metallic materials. Physical removal of rust requires expensive special equipment, and chemical removal of it can cause corrosion or shorten the life of the metal. In this study, an eco-friendly rust cleaner was developed using cosmetics and food materials by applying the concept of perm reducing agent and chelate, and applied to remove rust from industrial and hot water pipes and various industrial devices. As a result, it was found that rust cleaners remove rust more effectively and safely compared to conventional treatment methods. At the same time, the rust removal efficiency was 1.75 to 2.5 times better for industrial piping and 1.56 to 2.2 times better for boiler hot water than conventional methods.

Interpretation of Electrical Resistivity Tomogram with Contents of Clay Minerals for the Land Creeping Area (점토광물 함유량을 고려한 땅밀림 산사태 지역의 전기비저항 자료의 해석)

  • Kim, Jeong-In;Kim, Ji-Soo;Lee, Sun-Joong;Cho, Kyoung-Seo;Kim, Jong-Woo
    • The Journal of Engineering Geology
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    • v.31 no.2
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    • pp.187-197
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    • 2021
  • Clay mineral content of weathered zone is a key parameter for landslide studies. Electrical resistivity tomography is usually performed to delineate the geometry of complex landslides and to identify the sliding surface. In clay-bearing weathered zone, parallel resistivity Archie equation is employed to investigate the effect of conductivity added (resistivity reduced) by clay minerals of kaolinite and montmorillonite, which is dependent on their specific surface area and cation exchange capacities (CEC). A decrease of overall resistivity and apparent formation factor is observed with increasing pore-water resistivity, significantly in montmorillonite. Formation factor is found decreased with increasing porosity and decreasing cementation factor. Parallel Archie equation was applied to the electrical resistivity data from the test area (Sinjindo-ri, Taean-gun, Chungcheongnam-do, Korea) which experienced land creeping in the year of 2014. A panel test with varying clay-mineral contents provides the best fit section when the theoretical section constructed with the assumed contents approaches the field section, from which the clay-mineral content of the weathered zone is estimated to be approximately 10%. Resistivity interpretation schemes including the clay mineral contents for land creeping studies explored in this paper can be challenged more when porosity, saturation, and pore-water resistivity are provided and they are included in the numerical resistivity modeling.

A Qualitative Study on Continuing Bonds Experienced by Adolescent Victims' Parents of the Ferry Sewol Disaster : Focusing on implications for Grief Counseling by applying the Bereavement Two Track Model (세월호 재난으로 자녀를 잃은 부모의 지속유대 경험에 대한 질적 연구 : 사별 2축 이론을 적용한 애도상담에의 시사점을 중심으로)

  • Jeon, Ji-Yeol;Lee, Dong-Hun
    • The Journal of the Korea Contents Association
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    • v.22 no.7
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    • pp.443-477
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    • 2022
  • The purpose of this study was to explore the continuing bonds experienced by adolescent victims' 15 parents of the Sewol ferry disaster. The research aim is to classify the continuing bonds into representational, functional, emotional, and relationship characteristics through contents analysis and identify them. The way dimension was found to be continuing bond through "physical objects and space," "dream and spiritual exchange," "personal memorial and ritual activities," "thoughts of deceased children," and "surviving children." In the "functional dimension," it was found that sustainable ties help families find new meanings and purposes in their lives and comfort them by making them feel they are with their children. In addition, at the emotional level, they experienced 'positive emotions' while feeling with their children, and experienced 'pain', and some research participants found it difficult to sustain the bond itself. At the level of each relationship characteristic, the relationship between parents and children was an extension of the relationship even after the child was deceased, and the relationship characteristics were reproduced. The implications for grief counseling were presented by applying a dead two-axis model to the results of this study.

A Study on Sustainable Packaging for Flower Basket Design (지속 가능한 꽃바구니 디자인 패키징에 관한 연구)

  • Ahn, Hye Kyung;Kim, Heung Ryeol
    • Journal of the Korean Society of Floral Art and Design
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    • no.43
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    • pp.81-100
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    • 2020
  • Since sustainable packaging of flower basket designs that are sold from florist shops is needed for both the seller and the buyer, studying of second packaging of flower basket design has begun. In this study, based on the survey that has been done in 2019, and the analysis of the interview that has been done in 2020, the suggestion of sustainable packaging development is the purpose. The definition of flower basket design was done and surveys of the status of domestic flower basket designs' second packaging were done in accordance with the type of basket which is an object, transportation, and characteristic of a florist shop. For sustainable packaging, based on physical theory, second packaging which depends on the packaging that includes design factor, transportation final destination has to be different. The factors to be considered as sustainable packaging are the quality of opaque paper, the necessity of first packaging, packaging structure that can fix an object, the form of second packaging influenced by types of transportation. Suggestions for packaging development included new materials for first packaging, eco-friendly objects that can be recycled and reused, structural packaging design, standardization and variability of packaging, protection of floristry which is the fundamental purpose of packaging, and brand advertisement effect. Based on the result of this study further designs of packaging will be commercialized. This study is significant for serving the opportunity of new packaging design for futuristic floristry that fit for unmanned system and studying of categories of products.

An Analysis of Inquiry Activities Performed by Pre-service Elementary Teachers to Learn Optical Phenomena Using Algodoo Simulations (Algodoo 시뮬레이션을 활용한 초등 예비교사의 광학 현상 탐구 활동 분석)

  • Park, Jeongwoo
    • Journal of Korean Elementary Science Education
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    • v.41 no.3
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    • pp.538-552
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    • 2022
  • This study attempted to understand the characteristics of pedagogic activities performed by pre-service elementary school teachers. To this end, it applied Algodoo simulations to analyze the actions of students and obtain educational implications for optical learning. The study's participants comprised 79 first-year students enrolled in a teacher training college. Their activities could be classified as representation reproductions, verification experiments, and inquiry experiments. Students who performed representation reproduction exercises replicated renowned and authoritative exemplars, apprehending and demonstrating their principal features through simulations. Students performing verification experiments attempted to validate previously learned optical concepts by reviewing the relevant theoretical contexts. Such students primarily conducted simple experiments. Students accomplishing inquiry experiments used simulations to explore phenomena they did not know. Some of them even investigated optical phenomena beyond the domain of general physics. The above results confirmed that free optical experiments performed using Algodoo can effectively denote starting points for learners to engage in activities at varying levels. Additionally, students require assistance from instructors in addressing queries about the application of the principles and models related to optics. This study suggests ways in which instructors should help students at each level of activity. Additionally, the paper presents examples of varying levels of inquiry-related activities available on Algodoo. It also discusses the advantages and disadvantages of performing inquiry-based activities on Algodoo and suggests ways of enhancing the learning achieved through this platform.

A Semiotic Analysis of the Formation of Ecologically Educational Place Identity through Nature Trails in National Parks (국립공원 자연관찰로를 통한 생태교육적 장소정체성 형성에 대한 기호학적 해석)

  • Kim, Dong-Ryeul;Choi, Song-Hyun
    • Journal of Korean Elementary Science Education
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    • v.41 no.2
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    • pp.373-394
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    • 2022
  • This study aimed to find out the formation of ecologically educational place identity of nature trails in national parks, which elementary school students to adults can understand, by analyzing the connectivity between characteristics (signs) of nature trails and elementary science environment-related key concepts and the domain of ecological education in the course of environment and by developing a semiotic interpretation model of place identity based on Barthes's semiotic theory. When analyzing correlations between the interpretation board-focused surrounding environment of nature trails and the content system of ecological education, this study found out that it showed the highest connectivity with the domain of 'System of Ecological Environment'. When analyzing the formation of place identity of nature trails in terms of semiotics, this study discovered that geographical locations or landscapes, artificial environments and physical elements as characteristics of surrounding environments mostly acted on the formation of placeness. Besides, it was found that both knowledge and attachment elements equally could act on the formation of a sense of place. Being likely to develop through interaction between placeness and a sense of place, place identity was mostly composed of behavioral internal stages and sympathetic internal stages. To diversify the formation of place identity, however, this study found it necessary to develop environment education projects and create surrounding environments and interpretation boards with the environmental uniqueness of nature trails reflected much more.