• Title/Summary/Keyword: model studies

Search Result 16,600, Processing Time 0.045 seconds

The Affective Impact of Citizen Archival Activities: Toward a Conceptual and Analytical Framework (시민 기록활동의 정동적 영향: 개념과 분석 방안을 중심으로)

  • Eunhee Bae;Moon-Won Seol
    • Journal of Korean Society of Archives and Records Management
    • /
    • v.24 no.3
    • /
    • pp.65-84
    • /
    • 2024
  • Since the 2000s, there has been growing interest in community archival research in the West, and in Korea, projects that support citizen or resident participation in archival activities have also been increasing. With the role of community members as producers of records having gained importance in Korea, it has become necessary to examine the affective approach currently discussed in archival studies, focusing on the impact of "archival activities" on individual citizens. Unlike emotion, which is a personal and subjective experience, affect is characterized by "a sense shared based on relationships" and involves the concept of transformation of being (affection). This study aims to explore a method for analyzing the "affective impact applicable to citizen archival activities," an area that has not been previously addressed. To this end, the study reviews the meaning and concept of citizen archival activities and their development in Korea, focusing on the UCLA study (2018) and Brophy's (2005) approach to analyzing the affective impact of community archives to explore methodologies. It also explores the integration of the concept of "partyhood" to better reflect the characteristics of citizen archival activities. Based on these findings, this study proposes a conceptual model for analyzing the affective impact of citizen archival activities on recorders in Korea.

Effect of Expanded Polystyreneon Growth and Development Time of Tenebrio molitor (발포폴리스티렌이 Tenebrio molitor의 성장 및 발달 기간에 미치는 영향)

  • Ji Yun Yun;Se Min Lee;Soo Jin Jeong;Ava Johnston;Emelyn Anderson;Steven Kim;Dong Sub Kim
    • Journal of Bio-Environment Control
    • /
    • v.33 no.3
    • /
    • pp.172-177
    • /
    • 2024
  • Many studies have reported that mealworms can ingest plastic during their larval stage. The purpose of this study was to investigate the effects of expanded polystyrene consumption on the growth and development of mealworms during their larval stage. We found that the growth rate is significantly different between mealworms consumed wheat bran and mealworms consumed expanded polystyrene (p < 0.001). The transformation into pupa occurred faster among the mealworms consumed expanded polystyrene than those consumed wheat bran (p < 0.001). However, the survival rate was not significantly different between the two groups of mealworms (p = 0.786). Based on the data, we conclude that mealworms consuming expanded polystyrene have a slower weight gain and a shorter development period than mealworms consuming wheat bran, but the expanded polystyrene does not affect the survival rate before the transformation into pupa. Practically, we anticipate that mealworms can be a resource for the sustainable and eco-friendly removal of expanded polystyrene waste.

Aromadendrin Inhibits Lipopolysaccharide-Induced Inflammation in BEAS-2B Cells and Lungs of Mice

  • Juhyun Lee;Ji-Won Park;Jinseon Choi;Seok Han Yun;Bong Hyo Rhee;Hyeon Jeong Jeong;Hyueyun Kim;Kihoon Lee;Kyung-Seop Ahn;Hye-Gwang Jeong;Jae-Won Lee
    • Biomolecules & Therapeutics
    • /
    • v.32 no.5
    • /
    • pp.546-555
    • /
    • 2024
  • Aromadendrin is a phenolic compound with various biological effects such as anti-inflammatory properties. However, its protective effects against acute lung injury (ALI) remain unclear. Therefore, this study aimed to explore the ameliorative effects of aromadendrin in an experimental model of lipopolysaccharide (LPS)-induced ALI. In vitro analysis revealed a notable increase in the levels of cytokine/chemokine formation, nuclear factor kappa B (NF-κB) activation, and myeloid differentiation primary response 88 (MyD88)/toll-like receptor (TLR4) expression in LPS-stimulated BEAS-2B lung epithelial cell lines that was ameliorated by aromadendrin pretreatment. In LPS-induced ALI mice, the remarkable upregulation of immune cells and IL-1β/IL-6/TNF-α levels in the bronchoalveolar lavage fluid and inducible nitric oxide synthase/cyclooxygenase-2/CD68 expression in lung was decreased by the oral administration of aromadendrin. Histological analysis revealed the presence of cells in the lungs of ALI mice, which was alleviated by aromadendrin. In addition, aromadendrin ameliorated lung edema. This in vivo effect of aromadendrin was accompanied by its inhibitory effect on LPS-induced NF-κB activation, MyD88/TLR4 expression, and signal transducer and activator of transcription 3 activation. Furthermore, aromadendrin increased the expression of heme oxygenase-1/ NAD(P)H quinone dehydrogenase 1 in the lungs of ALI mice. In summary, the in vitro and in vivo studies demonstrated that aromadendrin ameliorated endotoxin-induced pulmonary inflammation by suppressing cytokine formation and NF-κB activation, suggesting that aromadendrin could be a useful adjuvant in the treatment of ALI.

The Effects of Gamification of e-Learning Platforms on Engagement: Focusing on Moderating Effects of Interaction, Difficulty, and Length (e-러닝 플랫폼의 게임화가 인게이지먼트에 미치는 영향: 상호작용, 스터디 난이도, 스터디 길이의 조절효과를 중심으로)

  • Ohsung Kim;Jungwon Lee
    • Information Systems Review
    • /
    • v.26 no.1
    • /
    • pp.73-91
    • /
    • 2024
  • Recently, e-learning platforms are rapidly growing by innovating the education industry by applying various IT technologies. Because student participation in the online environment is considered a prerequisite for learning, low participation rates are considered one of the most important issues determining the performance of e-learning platforms. Gamification has grown rapidly over the past decades and is highly valued for its applicability in education because it is expected to enhance learning motivation. However, despite the interest of researchers, previous studies have reported conflicting results on the effect of gamification on participation rates in the context of e-learning platforms, and have mainly studied structural gamification, but have not sufficiently addressed the effects of content gamification. In this context, this study aims to analyze the effect of content gamification on e-learning platform engagement and to explore the boundary conditions moderating this effect. For empirical analysis, 5,017 data registered from February 11, 2022 to May 31, 2022 were analyzed for the education platform entry (https://playentry.org). The propensity score matching method and Poisson multilevel regression model were applied as analysis methods. As a result of the analysis, content gamification had a statistically significant effect on engagement, and the interaction effects of interaction and content difficulty were statistically significant.

Open-ended Coaxial Probe Technique for the Dielectric Characterization of Propylene Carbonate, Dimethyl Carbonate and Their Mixtures from 0.1 to 8 GHz at 288.15, 298.15, and 308.15 K (개방 단말 동축선을 활용한 프로필렌 카보네이트, 디메틸 카보네이트 및 이들의 이성분계 혼합물의 유전 이완 측정과 해석)

  • Hyo Jung Kim;Seung-Wan Song;Tae Jun Yoon
    • Clean Technology
    • /
    • v.30 no.3
    • /
    • pp.228-238
    • /
    • 2024
  • Electrolytes are one of the essential components of a lithium-ion battery. They determine the battery's lifespan and cell characteristics. The dielectric constant is a key thermophysical property for determining how much salt can be dissociated and solvated in a solution. Hence, fast and reliable dielectric constant measurement is essential when formulating an electrolyte solution. This work implemented an open-ended coaxial probe (OECP) station as a quick and reliable tool to measure the complex permittivity spectra of electrolyte solutions. The capability of the OECP station was tested by measuring the complex permittivity of propylene carbonate (PC), dimethyl carbonate (DMC), and their mixtures from 0.1 to 8 GHz at 288.15, 298.15, and 308.15 K. The obtained dielectric spectra were then interpreted based on dielectric relaxation models and thermodynamic theories. The measured static dielectric constant data agreed well with the data from previous studies. They were also correlated using the Wang-Anderko thermodynamic model, showing approximately a 1% deviation from the experimental data. In addition, the relaxation characteristics, including the relaxation time and the Cole-Davidson exponent, showed that the microstructure of the solution significantly changes at the propylene carbonate mole fraction of 0.4. These results and methodologies are expected to contribute to the further understanding of electrolyte solutions and ultimately lead to the optimization of electrolyte formulation for lithium-ion batteries.

Development and Validation of a Korean Generative AI Literacy Scale (한국형 생성 인공지능 리터러시 척도 개발 및 타당화)

  • Hwan-Ho Noh;Hyeonjeong Kim;Minjin Kim
    • Knowledge Management Research
    • /
    • v.25 no.3
    • /
    • pp.145-171
    • /
    • 2024
  • Literacy initially referred to the ability to read and understand written documents and processed information. With the advancement of digital technology, the scope of literacy expanded to include the access and use of digital information, evolving into the concept of digital literacy. The application and purpose of digital literacy vary across different fields, leading to the use of various terminologies. This study focuses on generative artificial intelligence (AI), which is gaining increasing importance in the AI era, to assess users' literacy levels. The research aimed to extend the concept of literacy proposed in previous studies and develop a tool suitable for Korean users. Through exploratory factor analysis, we identified that generative AI literacy consists of four factors: AI utilization ability, critical evaluation, ethical use, and creative application. Subsequently, confirmatory factor analysis validated the statistical appropriateness of the model structure composed of these four factors. Additionally, correlation analyses between the newly developed literacy tool and existing AI literacy scales and AI service evaluation tools revealed significant relationships, confirming the validity of the tool. Finally, the implications, limitations, and directions for future research are discussed.

Dietary Calcium Intake and Colorectal Adenoma in Men and Women with Low Calcium Intake

  • Jioh Kang;Sang Hoon Kim;Joowon Chung;Dong Hyun Kim;Min Kyu Jung;Seun Ja Park;Hoon Jai Chun;Yun Jeong Lim;Hyun Jeong Cho;Jung Eun Lee
    • Journal of Digestive Cancer Research
    • /
    • v.12 no.2
    • /
    • pp.53-67
    • /
    • 2024
  • Backgrounds/Aims: Calcium is a preventive factor for colorectal cancer, which develops from colorectal adenoma. This study aimed to investigate the association between dietary calcium intake and prevalence of colorectal adenoma among Korean adults. Methods: Overall, 612 participants aged ≥ 20 years who underwent gastrointestinal endoscopy at 8 medical centers from 2021 to 2023 were included. Dietary calcium intake was assessed using a food frequency questionnaire and was energy-adjusted using the residual model. Multivariate logistic regression models were used to calculate for the odds ratios (ORs) and 95% confidence intervals (CIs). The associations between dietary calcium intake and colorectal adenoma prevalence were also assessed according to the anatomic subsites and adenoma status (advanced or nonadvanced). Results: Among the 612 participants, 269 were diagnosed with colorectal adenoma (170 men and 99 women). With respect to the gender-specific association, low dietary calcium intake was associated with higher prevalence of colorectal adenoma among men (ORs [95% CIs]: 2.13 [0.50-9.00] for < 250 mg/day; 3.53 [1.06-11.76], 250 to < 350 mg/day; and 1.84 [0.63-5.35], 350 to < 650 mg/day, compared to ≥ 650 mg/day of dietary calcium [p for trend = 0.07]). Similar association was observed among women, but neither the association nor trend was statistically significant (p for trend = 0.59). These inverse associations remained similar for distal colon/rectal adenoma among women and advanced adenoma among men. Conclusions: Low dietary calcium intake was associated with high colorectal adenoma prevalence, particularly among men. Given the limited number of studies among Asian populations, our findings should be replicated in other Asian groups.

A Study on the Methodology for Assessment of Safe Operating Envelope on Light Aircraft Carrier Using CFD Modeling Database of Flight Deck Air-wake (함재기 안전임무수행범주 평가를 위한 함정갑판 공기유동의 CFD 모델링 DB 활용연구)

  • Jae Hwan Jung;Dong-Min Park;Seok-Kyu Cho;Sa Young Hong
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.61 no.5
    • /
    • pp.312-323
    • /
    • 2024
  • This study aims to evaluate the safe operating envelope (SOE) for light aircraft carriers using a computational fluid dynamics (CFD) modeling database of flight deck air-wake. Assessing the SOE is crucial for ensuring the safe operation of carrier-based aircraft, particularly during take-off and landing maneuvers. Traditional methods that only consider relative wind envelopes (RWE) provide basic information but fail to account for the complex airflow patterns over the flight deck. To address this limitation, this research utilizes CFD to analyze the air-wake and integrate these findings into the SOE assessment. Various studies on CFD modeling of airflow around naval ships and aircraft carriers were reviewed, confirming the importance of accurate airflow databases for operational safety. This study employs the KRISO-CVX1 model, a light aircraft carrier designed by the Korea Research Institute of Ships & Ocean Engineering (KRISO), to demonstrate the application of CFD data in SOE evaluations. The methodology involves a detailed analysis of turbulent flow and thermal fields around the carrier deck under different wind speed, direction, and ship speed conditions. The results indicate significant variations in air-wake characteristics depending on the relative wind speed and direction, impacting the operational safety of carrier-based aircraft. This study emphasizes the need for incorporating CFD-based airflow data into SOE assessments to enhance the accuracy and reliability of operational safety evaluations for aircraft carriers. In conclusion, the integration of CFD air-wake modeling databases provides a more comprehensive approach to assessing the SOE, offering improved safety margins for carrier-based aircraft operations. This research is expected to contribute to the development of more robust and precise operational guidelines for naval aviation.

Stand Volume Estimation of Pinus Koraiensis Using Landsat TM and Forest Inventory (Landsat TM 영상과 현장조사를 이용한 잣나무림 재적 추정)

  • Park, Jin-Woo;Lee, Jung-Soo
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.17 no.1
    • /
    • pp.80-90
    • /
    • 2014
  • The objective of this research is to estimate the stand volume of Pinus koraiensis, by using the investigated volume and the information of remote sensing(RS), in the research forest of Kangwon National University. The average volume of the research forest per hectare was $307.7m^3/ha$ and standard deviation was $168.4m^3/ha$. Before and after carrying out 3 by 3 majority filtering on TM image, eleven indices were extracted each time. Independent variables needed for linear regression equation were selected using mean pixel values by indices. The number of indices were eleven: six Bands(except for thermal Band), NDVI, Band Ratio(BR1:Band4/Band3, BR2:Band5/Band4, BR3:Band7/Band4), Tasseled Cap-Greeness. As a result, NDVI and TC G were chosen as the most suitable indices for regression before and after filtering, and R-squared was high: 0.736 before filtering, 0.753 after filtering. As a result of error verification for an exact comparison, RMSE before and after filtering was about $69.1m^3/ha$, $67.5m^3/ha$, respectively, and bias was $-12.8m^3/ha$, $9.7m^3/ha$, respectively. Therefore, the regression conducted with filtering was selected as an appropriate model because of low RMSE and bias. The estimated stand volume applying the regression was $160,758m^3$, and the average volume was $314m^3/ha$. This estimation was 1.2 times higher than the actual stand volume of Pinus koraiensis.

The Liability for Damage and Dispute Settlement Mechanism under the Space Law (우주법상 손해배상책임과 분쟁해결제도)

  • Lee, Kang-Bin
    • Journal of Arbitration Studies
    • /
    • v.20 no.2
    • /
    • pp.173-198
    • /
    • 2010
  • The purpose of this paper is to research on the liability for the space damage and the settlement of the dispute with reference to the space activity under the international space treaty and national space law of Korea. The United Nations has adopted five treaties relating to the space activity as follows: The Outer Space Treaty of 1967, the Rescue and Return Agreement of 1968, the Liability Convention of 1972, the Registration Convention of 1974, and the Moon Treaty of 1979. All five treaties have come into force. Korea has ratified above four treaties except the Moon Treaty. Korea has enacted three national legislations relating to space development as follows: Aerospace Industry Development Promotion Act of 1987, Outer Space Development Promotion Act of 2005, Outer Space Damage Compensation Act of 2008. The Outer Space Treaty of 1967 regulates the international responsibility for national activities in outer space, the national tort liability for damage by space launching object, the national measures for dispute prevention and international consultation in the exploration and use of outer space, the joint resolution of practical questions by international inter-governmental organizations in the exploration and use of outer space. The Liability Convention of 1972 regulates the absolute liability by a launching state, the faulty liability by a launching state, the joint and several liability by a launching state, the person claiming for compensation, the claim method for compensation, the claim period of compensation, the claim for compensation and local remedy, the compensation amount for damage by a launching state, the establishment of the Claims Commission. The Outer Space Damage Compensation Act of 2008 in Korea regulates the definition of space damage, the relation of the Outer Space Damage Compensation Act and the international treaty, the non-faulty liability for damage by a launching person, the concentration of liability and recourse by a launching person, the exclusion of application of the Product Liability Act, the limit amount of the liability for damage by a launching person, the cover of the liability insurance by a launching person, the measures and assistance by the government in case of occurring the space damage, the exercise period of the claim right of compensation for damage. The Liability Convention of 1972 should be improved as follows: the problem in respect of the claimer of compensation for damage, the problem in respect of the efficiency of decision by the Claims Commission. The Outer Space Damage Compensation Act of 2008 in Korea should be improved as follows: the inclusion of indirect damage into the definition of space damage, the change of currency unit of the limit amount of liability for damage, the establishment of joint and several liability and recourse right for damage by space joint launching person, the establishment of the Space Damage Compensation Review Commission. The 1998 Final Draft Convention on the Settlement of Disputes Related to Space Activities of 1998 by ILA regulates the binding procedure and non-binding settlement procedure for the disputes in respect of space activity. The non-binding procedure regulates the negotiation or the peaceful means and compromise for dispute settlement. The binding procedure regulates the choice of a means among the following means: International Space Law Court if it will be established, International Court of Justice, and Arbitration Court. The above final Draft Convention by ILA will be a model for the innovative development in respect of the peaceful settlement of disputes with reference to space activity and will be useful for establishing the frame of practicable dispute settlement. Korea has built the space center at Oinarodo, Goheung Province in June 2009. Korea has launched the first small launch vehicle KSLV-1 at the Naro Space Center in August 2009 and June 2010. In Korea, it will be the possibility to be occurred the problems relating to the international responsibility and dispute settlement, and the liability for space damage in the course of space activity. Accordingly the Korean government and launching organization should make the legal and systematic policy to cope with such problems.

  • PDF