• Title/Summary/Keyword: System Identification

Search Result 5,981, Processing Time 0.037 seconds

3SLS Analysis of Technology Innovation, Employment, and Corporate Performance of South Korean Manufacturing Firms: A Quantity and Quality of Employment Perspective (한국 제조기업의 기술혁신, 고용, 기업성과 간 관계에 대한 3SLS 분석: 고용의 양적·질적 특성 관점에서)

  • Dong-Geon Lim;Jin Hwa Jung
    • Journal of Technology Innovation
    • /
    • v.31 no.3
    • /
    • pp.139-169
    • /
    • 2023
  • This study analyzes the effects of firms' technology innovation(patent applications) on employment(number of workers and proportion of high-skilled workers) and corporate performance(sales per worker), while considering the two-way causal relationships between these variables. We used the three-stage least squares(3SLS) estimation to examine system of equations in which the dependent variables affect each other with a two-year lag wherever relevant, and applied it to firm-level panel data of Korean manufacturers with 100 or more workers. Our data covered the period of 2005-2017. Exogenous variables, such as firms' managerial and other characteristics, were controlled as explanatory variables. The identification variables for each equation included firms' R&D intensity, labor cost per worker(or operation of firms' own R&D center), and investment on worker training. We find that firms' patent applications increased number of workers, proportion of high-skilled workers, and sales per worker; the causal relationships in the opposite direction were also significant. Evidently, firms' technology innovation is critical to the growth and quality improvement of employment as well as sustainable corporate growth.

A Gap Analysis Using Spatial Data and Social Media Big Data Analysis Results of Island Tourism Resources for Sustainable Resource Management (지속가능한 자원관리를 위한 섬 지역 관광자원의 공간정보와 소셜미디어 빅데이터 분석 결과를 활용한 격차분석)

  • Lee, Sung-Hee;Lee, Ju-Kyung;Son, Yong-Hoon;Kim, Young-Jin
    • Journal of Korean Society of Rural Planning
    • /
    • v.30 no.2
    • /
    • pp.13-24
    • /
    • 2024
  • This study conducts an analysis of social media big data pertaining to island tourism resources, aiming to discern the diverse forms and categories of island tourism favored by consumers, ascertain predominant resources, and facilitate objective decision-making grounded in scientific methodologies. To achieve this objective, an examination of blog posts published on Naver from 2022 to 2023 was undertaken, utilizing keywords such as 'Island tourism', 'Island travel', and 'Island backpacking' as focal points for analysis. Text mining techniques were applied to sift through the data. Among the resources identified, the port emerged as a significant asset, serving as a pivotal conduit linking the island and mainland and holding substantial importance as a focal point and resource for tourist access to the island. Furthermore, an analysis of the disparity between existing island tourism resources and those acknowledged by tourists who actively engage with and appreciate island destinations led to the identification of 186 newly emerging resources. These nascent resources predominantly clustered within five regions: Incheon Metropolitan City, Tongyeong/Geoje City, Jeju Island, Ulleung-gun, and Shinan-gun. A scrutiny of these resources, categorized according to the tourism resource classification system, revealed a notable presence of new resources, chiefly in the domains of 'rural landscape', 'tourist resort/training facility', 'transportation facility', and 'natural resource'. Notably, many of these emerging resources were previously overlooked in official management targets or resource inventories pertaining to existing island tourism resources. Noteworthy examples include ports, beaches, and mountains, which, despite constituting a substantial proportion of the newly identified tourist resources, were not accorded prominence in spatial information datasets. This study holds significance in its ability to unearth novel tourism resources recognized by island tourism consumers through a gap analysis approach that juxtaposes the existing status of island tourism resource data with techniques utilizing social media big data. Furthermore, the methodology delineated in this research offers a valuable framework for domestic local governments to gauge local tourism demand and embark on initiatives for tourism development or regional revitalization.

A Study on Microbial Community Diversity and Antibiotic Resistance in Public Waters in Gwangju (광주지역 공공수역의 미생물 군집 다양성 및 항생제 내성에 관한 연구)

  • Sun-Jung Kim;Ji-Young Park;Seung-Ho Kim;Min-Hwa Lim;Ji-Yong Yu;Kyu-Sung Han;Se-Il Park;Gwangyeob Seo;Gwangwoon Cho
    • Journal of Environmental Health Sciences
    • /
    • v.50 no.2
    • /
    • pp.93-101
    • /
    • 2024
  • Background: As pollutants caused by non-point sources flow into rivers, river water quality monitoring for fecal pollution is becoming increasingly important. Objectives: This study was conducted to investigate the distribution of microbial communities in the Yeongsangang River water system and sewage treatment plants in Gwangju and to evaluate their antibiotic resistance. Methods: In the experiment, samples were distributed to five selective media at each point and then cultured for 18 to 24 hours. When bacteria were observed, they were sub-cultured by size and shape and identified using MALDI-TOF MS equipment. When identification was completed, 17 types of antibiotic susceptibility tests were performed using VITEK II equipment, focusing on gram-negative dominant species among the identified strains. Results: During the study period, a total of 266 strains were isolated from 39 samples. Gram-positive bacteria were 37 strains in four genera, or 13.9% of the total, and Gram-negative bacteria were 229 strains in 23 genera, or 86.1% of the total. Antibiotic susceptibility testing of 23 strains, the major dominant species, showed that one strain (4.3%) was resistant to only one antibiotic, and two strains (8.7%) were 100% susceptible to the 17 antibiotics tested. The other 20 strains (87.0%) were multidrug resistant bacteria resistant to two or more antibiotics. There were various types of multidrug resistance. Among them, penicillin and cephalosporin series showed the highest resistance. Conclusions: Based on the results of this study, it was found that the bacterial community structure changed according to regional and environmental factors, and it was judged that continuous research such as genetic analysis of antibiotic-resistant bacteria present in natural rivers is necessary.

The Molecular Insight into the Vascular Endothelial Growth Factor in Cancer: Angiogenesis and Metastasis (암의 혈관내피 성장인자에 대한 분자적 통찰: 혈관신생과 전이)

  • Han Na Lee;Chae Eun Seo;Mi Suk Jeong;Se Bok Jang
    • Journal of Life Science
    • /
    • v.34 no.2
    • /
    • pp.128-137
    • /
    • 2024
  • This review discusses the pivotal role of vascular endothelial growth factors (VEGF) in angiogenesis and lymphangiogenesis, vital processes influencing vascular permeability, endothelial cell recruitment, and the maintenance of tumor-associated blood and lymphatic vessels. VEGF exerts its effects through tyrosine-kinase receptors, VEGFR-1, VEGFR-2, and VEGFR-3. This VEGF-VEGFR system is central not only to cancer but also to diseases arising from abnormal blood vessel and lymphatic vessel formation. In the context of cancer, VEGF and its receptors are essential for the development of tumor-associated vessels, making them attractive targets for therapeutic intervention. Various approaches, such as anti-VEGF antibodies, receptor antagonists, and VEGF receptor function inhibitors, are being explored to interfere with tumor growth. However, the clinical efficacy of anti-angiogenic agents remains uncertain and necessitates further refinement. The article also highlights the physiological role of VEGFs, emphasizing their involvement in endothelial cell functions, survival, and vascular permeability. The identification of five distinct VEGFs in humans (VEGF-A, VEGF-B, VEGF-C, VEGF-D, and PLGF) is discussed, along with the classification of VEGFRs as typical receptor tyrosine kinases with distinct signaling systems. The family includes VEGFR-1 and VEGFR-2, crucial in tumor biology and angiogenesis, and VEGFR-3, specifically involved in lymphangiogenesis. Overall, this review has provided a comprehensive overview of VEGF and VEGFR, detailing their roles in various diseases, including cancer. This is expected to further facilitate the utilization of VEGF and VEGFR as therapeutic targets.

A Study on Metadata Design for Managing Person and Organization Names in the National Debt Redemption Movement Digital Archive (국채보상운동 디지털 아카이브의 개인/단체명 관리를 위한 메타데이터 설계에 관한 연구)

  • Sangeun Han;Seulki Do
    • Journal of the Korean Society for information Management
    • /
    • v.41 no.1
    • /
    • pp.509-536
    • /
    • 2024
  • The purpose of this study is to develop a metadata AP for managing the person and organization name authority data in the National Debt Redemption Movement Digital Archive, a small-scale digital archive. The design principles and core metadata elements were derived by analyzing person/organization(group or corporateBody) metadata standards, implementation practices, and guidelines of libraries and archives, and mapped to the National Debt Redemption Movement person/organization name thesaurus data and the Wikidata Linked Metadata Model, resulting in 10 elements in the identification area, 14 elements in the content area, 8 elements in the relationship area, and 4 elements in the control area. A simple structure schema was applied so that it can be applied even in small organizations, and for interoperability, the schema was proposed with reference to DublinCore and SKOS schemes, and the applicability was confirmed based on actual data. The results of this study can be utilized as a basis for institutions that recognize the importance of data management but have difficulty in applying it in practice, when they want to prepare a system for managing their own authority data.

Trends identification of species distribution modeling study in Korea using text-mining technique (텍스트마이닝을 활용한 종분포모형의 국내 연구 동향 파악)

  • Dong-Joo Kim;Yong Sung Kwon;Na-Yeon Han;Do-Hun Lee
    • Korean Journal of Environmental Biology
    • /
    • v.41 no.4
    • /
    • pp.413-426
    • /
    • 2023
  • Species distribution model (SDM) is used to preserve biodiversity and climate change impact. To evaluate biodiversity, various studies are being conducted to utilize and apply SDM. However, there is insufficient research to provide useful information by identifying the current status and recent trends of SDM research and discussing implications for future research. This study analyzed the trends and flow of academic papers, in the use of SDM, published in academic journals in South Korea and provides basic information that can be used for related research in the future. The current state and trends of SDM research were presented using philological methods and text-mining. The papers on SDM have been published 148 times between 1998 and 2023 with 115 (77.7%) papers published since 2015. MaxEnt model was the most widely used, and plant was the main target species. Most of the publications were related to species distribution and evaluation, and climate change. In text mining, the term 'Climate change' emerged as the most frequent keyword and most studies seem to consider biodiversity changes caused by climate change as a topic. In the future, the use of SDM requires several considerations such as selecting the models that are most suitable for various conditions, ensemble models, development of quantitative input variables, and improving the collection system of field survey data. Promoting these methods could help SDM serve as valuable scientific tools for addressing national policy issues like biodiversity conservation and climate change.

Development and mathematical performance analysis of custom GPTs-Based chatbots (GPTs 기반 문제해결 맞춤형 챗봇 제작 및 수학적 성능 분석)

  • Kwon, Misun
    • Education of Primary School Mathematics
    • /
    • v.27 no.3
    • /
    • pp.303-320
    • /
    • 2024
  • This study presents the development and performance evaluation of a custom GPT-based chatbot tailored to provide solutions following Polya's problem-solving stages. A beta version of the chatbot was initially deployed to assess its mathematical capabilities, followed by iterative error identification and correction, leading to the final version. The completed chatbot demonstrated an accuracy rate of approximately 89.0%, correctly solving an average of 57.8 out of 65 image-based problems from a 6th-grade elementary mathematics textbook, reflecting a 4 percentage point improvement over the beta version. For a subset of 50 problems, where images were not critical for problem resolution, the chatbot achieved an accuracy rate of approximately 91.0%, solving an average of 45.5 problems correctly. Predominant errors included problem recognition issues, particularly with complex or poorly recognizable images, along with concept confusion and comprehension errors. The custom chatbot exhibited superior mathematical performance compared to the general-purpose ChatGPT. Additionally, its solution process can be adapted to various grade levels, facilitating personalized student instruction. The ease of chatbot creation and customization underscores its potential for diverse applications in mathematics education, such as individualized teacher support and personalized student guidance.

Towards Efficient Aquaculture Monitoring: Ground-Based Camera Implementation for Real-Time Fish Detection and Tracking with YOLOv7 and SORT (효율적인 양식 모니터링을 향하여: YOLOv7 및 SORT를 사용한 실시간 물고기 감지 및 추적을 위한 지상 기반 카메라 구현)

  • TaeKyoung Roh;Sang-Hyun Ha;KiHwan Kim;Young-Jin Kang;Seok Chan Jeong
    • The Journal of Bigdata
    • /
    • v.8 no.2
    • /
    • pp.73-82
    • /
    • 2023
  • With 78% of current fisheries workers being elderly, there's a pressing need to address labor shortages. Consequently, active research on smart aquaculture technologies, centered on object detection and tracking algorithms, is underway. These technologies allow for fish size analysis and behavior pattern forecasting, facilitating the development of real-time monitoring and automated systems. Our study utilized video data from cameras outside aquaculture facilities and implemented fish detection and tracking algorithms. We aimed to tackle high maintenance costs due to underwater conditions and camera corrosion from ammonia and pH levels. We evaluated the performance of a real-time system using YOLOv7 for fish detection and the SORT algorithm for movement tracking. YOLOv7 results demonstrated a trade-off between Recall and Precision, minimizing false detections from lighting, water currents, and shadows. Effective tracking was ascertained through re-identification. This research holds promise for enhancing smart aquaculture's operational efficiency and improving fishery facility management.

Identification and molecular characterization of the chitinase gene, EaChi, from the midgut of the earthworm, Eisenia andrei (붉은줄지렁이 (Eisenia andrei) 중장에서 발현되는 chitinase 유전자, EaChi의 동정 및 분자생물학적 특성에 관한 연구)

  • Tak, Eun Sik;Kim, Dae hwan;Lee, Myung Sik;Ahn, Chi Hyun;Park, Soon Cheol
    • Journal of the Korea Organic Resources Recycling Association
    • /
    • v.18 no.3
    • /
    • pp.31-37
    • /
    • 2010
  • Chitinases (EC 3.2.1.14) hydrolyze the ${\beta}$-1,4-linkages in chitin, the second most abundant polymer of N-acetyl-${\beta}$-D-glucosamine which is a structural component of protective biological matrices such as fungal cell walls and insect exoskeletons. The glycosyl hydrolases 18 family including chitinases is an ancient gene family widely expressed in archea, prokaryotes and eukaryotes. Since earthworms live in the soil with a lot of microbial activities and fungi are supposed to be a major component of the diet of earthworm, it has been reported that there would be appropriate immune system to protect themselves from microorganisms attacks. In this study, the novel chitinase, EaChi, from the midgut of earthworm, Eisenia andrei, were identified and characterized. To obtain full-length cDNA sequence of chitinase, RT-PCR and RACE-PCR analyses were carried out by using the previously identified EST sequence amongst cDNA library established from the midgut of E. andrei. EaChi, a partial chitinase gene, was composed of 927 nucleotides encoding 309 amino acids. By the multiple sequence alignments of amino acids with other different species, it was revealed that EaCHI is a member of glycosyl hydrolases 18 family, which has two highly conserved domains, substrate binding and catalytic domain.

A Study on the Countmeasures of the Korean Pharmaceutical/Bio Industry to the EU Corporate Sustainability Due Diligence Directive, by using Text Mining (텍스트 마이닝을 활용한 국내 제약·바이오 업종의 EU 공급망 실사법 대응 방안 연구)

  • Sori Kim;Joonhak Ki
    • Information Systems Review
    • /
    • v.26 no.1
    • /
    • pp.93-117
    • /
    • 2024
  • In February 2022, the EU announced a draft of the EU Corporate Sustainability Due Diligence Directive requiring due diligence and disclosure of information on environmental and human rights risks in corporate supply chains. This study evaluated the ability of 13 Korean pharmaceutical/bio companies to respond to the EU's demand for due diligence in the supply chain and compared it to 13 globally leading pharmaceutical/bio companies which are considered good in environmental and human rights risk management. For comparative analysis, text mining analysis was performed using R. Basic word frequency and concurrent words were analyzed and topic modeling was performed by applying Latent Dirichlet Allocation. As a result of the analysis, it was found that compared to advanced companies, domestic pharmaceutical and bio companies lack negative issue reporting and identification systems and supply chain due diligence implementation processes, and require advancement of data management for environmental and human rights information disclosure. Accordingly, domestic pharmaceutical and bio companies need to prepare differentiated support measures to systematically identify and reduce risks in the supply chain of small and medium-sized businesses beyond simply providing financial support. It is also desirable for the government to provide policy support by mandating Korea's own supply chain environment and human rights due diligence system, along with support for strengthening the ability to respond to due diligence of domestic pharmaceutical and bio companies, such as expert consulting and financial support.