• Title/Summary/Keyword: current source

Search Result 4,027, Processing Time 0.033 seconds

Protective Effects of Traditional Korean Medicine Preparations, Herbs, and Active Compounds on the Blood-brain Barrier in Ischemic Stroke Models (허혈성 뇌졸중 모델에서 혈액-뇌 장벽에 보호효과를 나타내는 한약처방, 한약재 및 활성화합물)

  • Shin, Su Bin;Jang, Seok Ju;Lee, Na Gyeong;Choi, Byung Tae;Shin, Hwa Kyoung
    • Journal of Life Science
    • /
    • v.32 no.7
    • /
    • pp.550-566
    • /
    • 2022
  • Stroke is among the leading causes of death and long-term physical and cognitive disabilities worldwide, affecting an estimated 15 million people annually. The pathophysiological process of stroke is complicated by multiple and coordinated events. The breakdown of the blood-brain barrier (BBB) in people with stroke can significantly contribute to the development of ischemic brain injury. Therefore, BBB disruption is recognized as a hallmark of stroke; thus, it is important to develop novel therapeutic strategies that can protect against BBB dysfunction in ischemic stroke. Traditional medicines are composed of natural products, which represent a promising source of new ingredients for the development of conventional medicines. Indeed, several studies have shown the effectiveness of Korean medicine on stroke, highlighting the value of Korean medicinal treatment for ischemic stroke. This review summarizes the current information and underlying mechanisms regarding the ameliorating effects of the formula, decoction, herbs, and active components of traditional Korean medicine on cerebral ischemia-induced BBB disruption. These traditional medicines were shown to have protective effects on the BBB in many cellular and animal ischemia models of stroke, and experiments in various animal species, such as mice and rats. In addition, they showed brain-protective effects by protecting the BBB through the regulation of tight junction proteins and matrix metalloproteinase-9, reducing edema, neuroinflammation, and neuronal cell death. We hope that this review will help promote further investigation into the neuroprotective effects of traditional Korean medicines and stimulate the performance of clinical trials on Korean herbal medicine-derived drugs in patients with stroke.

Voice Interactions with A. I. Agent : Analysis of Domestic and Overseas IT Companies (A.I.에이전트와의 보이스 인터랙션 : 국내외 IT회사 사례연구)

  • Lee, Seo-Young
    • Journal of Korea Entertainment Industry Association
    • /
    • v.15 no.4
    • /
    • pp.15-29
    • /
    • 2021
  • Many countries and companies are pursuing and developing Artificial intelligence as it is the core technology of the 4th industrial revolution. Global IT companies such as Apple, Microsoft, Amazon, Google and Samsung have all released their own AI assistant hardware products, hoping to increase customer loyalty and capture market share. Competition within the industry for AI agent is intense. AI assistant products that command the biggest market shares and customer loyalty have a higher chance of becoming the industry standard. This study analyzed the current status of major overseas and domestic IT companies in the field of artificial intelligence, and suggested future strategic directions for voice UI technology development and user satisfaction. In terms of B2B technology, it is recommended that IT companies use cloud computing to store big data, innovative artificial intelligence technologies and natural language technologies. Offering voice recognition technologies on the cloud enables smaller companies to take advantage of such technologies at considerably less expense. Companies also consider using GPT-3(Generative Pre-trained Transformer 3) an open source artificial intelligence language processing software that can generate very natural human-like interactions and high levels of user satisfaction. There is a need to increase usefulness and usability to enhance user satisfaction. This study has practical and theoretical implications for industry and academia.

Development of High-Sensitivity and Entry-Level Nuclide Analysis Module (고감도 보급형 핵종 분석 모듈 개발)

  • Oh, Seung-Jin;Lee, Joo-Hyun;Lee, Seung-Ho
    • Journal of IKEEE
    • /
    • v.26 no.3
    • /
    • pp.515-519
    • /
    • 2022
  • In this paper, we propose the development of a high-sensitivity entry-level nuclide analysis module. The proposed measurement sensor module consists of an electronic driving circuit for nuclide analysis resolution, prototype production with nuclide analysis function, and GUI development applied to prototypes. The electronic part driving circuit for nuclide analysis resolution is divided into nuclide analysis resolution process by the electronic part driving circuit block diagram, MCU circuit design used for radiation measurement, and PC program design for Spectrum acquisition. Prototyping with nuclide analysis function is made by adding a 128×128 pixel OLED display, three buttons for operation, a Li-ion battery, and a USB-C type port for charging the battery. The GUI development department applied to the prototype develops the screen composition such as the current time, elapsed measurement time, total count, and nuclide Spectrum. To evaluate the performance of the proposed measurement sensor module, an expert witness test was conducted. As a result of the test, it was confirmed that the calculated result by applying the resolution formula to the Spectrum (FWHM@662keV) obtained using the Cs-137 standard source in the nuclide analysis device had a resolution of 17.77%. Therefore, it was confirmed that the nuclide analysis resolution method proposed in this paper produces improved performance while being cheaper than the existing commercial nuclide analysis module.

Investigation of the listening environment for lower grade students in elementary school using subjective tests (주관적 평가법을 이용한 초등학교 저학년 교실의 청취환경 조사)

  • Park, Chan-Jae;Haan, Chan-Hoon
    • The Journal of the Acoustical Society of Korea
    • /
    • v.40 no.3
    • /
    • pp.201-212
    • /
    • 2021
  • The present study was conducted as a pilot investigation to suggest the standards of acoustic performance for classrooms suitable for incomplete hearing people such as children under 9 years of age. Subjective evaluations such as questionnaire and speech intelligibility test were conducted to 264 students at two elementary schools in Cheong-ju in order to analyze the characteristics of the listening environment in the classrooms of the lower grades in elementary school. The survey was undertaken with a total of 264 students at two elementary schools in Cheong-ju, and investigated their satisfaction with the classroom listening environment. As a result, students responded that the most helpful information type for understanding class content is the voice of teacher. In addition, the volume of the current teacher's voice is normal, and the level of clarity is highly satisfactory. As for the acoustic performance of the classroom, the opinion that the noise was normal and the reverberation was very short was found to be dominant in overall satisfaction with the listening environment. Meanwhile, as a result of speech intelligibility test using the word list selected for the lower grade students of elementary school, it could be inferred that the longitudinal axis distance from the sound source in the case of 8-year-olds is a factor that affects speech recognition.

A Study on the Current Status and Characteristics of Fine Dust Generation in Construction Waste Intermediate Treatment Plants and Neighboring Areas (건설폐기물 중간처리 사업장과 인근 지역의 미세먼지 발생 현황 및 특성에 관한 연구)

  • Jang, Kyong-Pil;Song, Tae-Hyeob;Kim, Byung-Yun
    • Journal of the Korean Recycled Construction Resources Institute
    • /
    • v.9 no.4
    • /
    • pp.405-412
    • /
    • 2021
  • The objective of this study is to investigate the environmental impact of fine dust generated at the construction waste intermediate treatment plants, and to propose engineering data and measures to suppress the generation of fine dust to cope with the expected strengthened environmental regulations of the government. The following study conclusions are drawn. 1) T he maximum concentration of fine dust in the workplace was measured as 160㎍/m3 from the crushing operation followed by the point of waste unloading, where focused suppression plan of the fine dust generation is needed in the future. 2) Fine dust concentrations of 113㎍/m3 in wet road conditions and 50㎍/m3 in dry conditions were measured, indicating that fine dust could be reduced by 50% with watering alone. 3) The effect of distancing from the dust source was studied. PM10 during operation of the workplace was measured as about 25㎍/m3 higher than those of the neighboring areas. Whereas there was no significant difference in case of PM2.5 between workplace and neighboring areas. 4) The measurement results of the heavy metal contents showed that these metals did not affect neighboring areas.

Anti-melanogenic Effects of Cnidium japonicum in B16F10 Murine Melanoma Cells (B16F10 피부 흑색종세포에서 갯사상자 추출물의 멜라닌 합성 저해 효과)

  • Jo, Hyun Jin;Karadeniz, Fatih;Oh, Jung Hwan;Seo, Youngwan;Kong, Chang-Suk
    • Journal of Life Science
    • /
    • v.32 no.5
    • /
    • pp.331-339
    • /
    • 2022
  • Melanin is a pigment produced by melanocytes to protect the skin from external stimuli, mainly ultraviolet (UV) rays. However, abnormal and excessive production of melanin causes hyperpigmentation disorders, such as freckles, age spots, and discoloration. Natural cosmeceuticals are a new trend for treating or preventing hyperpigmentation due to fewer side effects and biocompatibility. In this context, the current study focused on Cnidium japonicum, a halophyte with several uses in folk medicine, to evaluate its potential as a skin-whitening agent. The effect of C. japonicum extract (CJE) on melanin production was analyzed in melanogenesis-stimulated B16F10 melanoma cells. The results showed that CJE successfully inhibited the oxidation of tyrosine and L-DOPA by tyrosinase and subsequently decreased the production of the key enzymes responsible for melanin production: tyrosinase, tyrosinase-related protein-1, and protein-2. This effect was confirmed by decreased intracellular and extracellular melanin levels in B16F10 melanoma cells after CJE treatment. Further experiments to elucidate the action mechanism revealed that CJE treatment suppressed melanin production by inhibiting the activation of glycogen synthase kinase 3 β (GSKβ)/β-catenin and protein kinase A (PKA)/cAMP-response element binding protein (CREB) pathways, which are the upstream activators of melanogenesis. In conclusion, the present study suggests that C. japonicum is a potential natural source of bioactive substances for the development of novel cosmeceuticals that can act against hyperpigmentation.

Plant-derived Anti-HIV Natural Products: A Review of Recent Research (천연물의 항 HIV 효능에 대한 최신 연구동향)

  • Karadeniz, Fatih;Oh, Jung Hwan
    • Journal of Life Science
    • /
    • v.32 no.9
    • /
    • pp.734-741
    • /
    • 2022
  • Currently, around 40 million people worldwide are living with human immunodeficiency virus (HIV) infection making HIV a critical global health risk. Present therapies for HIV infection consist of drug cocktails that target different steps of the HIV life cycle to prevent infection, replication, and release of the virus. Due to its mutating nature, drug resistance coupled with side-effects of long-term drug use, novel strategies, and pharmaceuticals to treat and manage HIV infection are constant needs and continuously being studied. Plants allocate a major repertoire of chemical diversity and are therefore regarded as an important source of new bioactive agents that can be utilized against HIV. Since the early 1990s, upon recommendations of the World Health Organization, numerous studies reported phytochemicals from different structural classes such as flavonoids, coumarins, tannins and terpenes with strong inhibitory effects against HIV infection. The present review gathered and presented recent research (2021-present) on plant extracts and phytochemicals that exhibit anti-HIV properties with the aim of providing insights into future studies where ethnomedical and underutilized plant sources may yield important natural products against HIV. Considering the relation and importance of HIV treatment with current viral infection risks such as SARS-CoV-2, screening plants for anti-HIV agents is an important step towards the discovery of novel antivirals.

The Effects of Firms' Engagement in Fair Trade Practice on Consumers' Purchase Intention : An Experimental Study on Koreans' Attitude toward Foreign Coffee Brands (기업의 공정무역행위가 소비자들의 제품 구매의도에 미치는 영향 - 한국 소비자들의 커피 브랜드 태도에 관한 실험을 중심으로 -)

  • Kim, Min-Hee;Kim, Min-Ho;Oh, Han-Mo
    • Korea Trade Review
    • /
    • v.41 no.5
    • /
    • pp.1-14
    • /
    • 2016
  • Consumers have been increasing their interests in firms' ethicality as well as in the features of the firms' products when they decide to purchase a certain product. Recently, fair trade is considered to be a type of ethical marketing in the business-to-consumer market. In this regard, the effects of fair trade-based marketing on firm performance have become the center of academic and managerial concerns. Despite this importance, few studies have investigated whether fair-trade is a source of competitive advantage or just a cost of doing business. The present research attempts to provide evidence of how fair trade-based marketing influences competitive advantage. Two experimental studies were conducted to explore consumers' purchase intention, which can be a proxy of competitive advantage, in a foreign product-consumption context. Drawing on the stakeholder theory, the first study was performed to examine the effects of fair trade marketing on consumers' purchase intention through a within-subjects design. In addition, building on the signal theory, the second study was executed to test the effects of a fair trade mark on consumers' purchase intention. The findings of the current research reveal that consumers prefer fair trade-based products to others and that when it comes to fair trade-certified products, consumers are more likely to purchase products with that certification than otherwise, even when those products are sold at higher costs than rival products. Interestingly, the results of this research present that there is a significant difference of consumers' purchase intention of a fair trade-based product between two different marketers. This implies that fair trade-based products should be differentially distributed and targeted at a certain type of consumers.

  • PDF

KOMUChat: Korean Online Community Dialogue Dataset for AI Learning (KOMUChat : 인공지능 학습을 위한 온라인 커뮤니티 대화 데이터셋 연구)

  • YongSang Yoo;MinHwa Jung;SeungMin Lee;Min Song
    • Journal of Intelligence and Information Systems
    • /
    • v.29 no.2
    • /
    • pp.219-240
    • /
    • 2023
  • Conversational AI which allows users to interact with satisfaction is a long-standing research topic. To develop conversational AI, it is necessary to build training data that reflects real conversations between people, but current Korean datasets are not in question-answer format or use honorifics, making it difficult for users to feel closeness. In this paper, we propose a conversation dataset (KOMUChat) consisting of 30,767 question-answer sentence pairs collected from online communities. The question-answer pairs were collected from post titles and first comments of love and relationship counsel boards used by men and women. In addition, we removed abuse records through automatic and manual cleansing to build high quality dataset. To verify the validity of KOMUChat, we compared and analyzed the result of generative language model learning KOMUChat and benchmark dataset. The results showed that our dataset outperformed the benchmark dataset in terms of answer appropriateness, user satisfaction, and fulfillment of conversational AI goals. The dataset is the largest open-source single turn text data presented so far and it has the significance of building a more friendly Korean dataset by reflecting the text styles of the online community.

Approaches to Creating a Digital Encyclopedia of Korean Archaeology (한국고고학 디지털 사전 구축 방안 연구)

  • LEE Chorong
    • Korean Journal of Heritage: History & Science
    • /
    • v.56 no.2
    • /
    • pp.28-45
    • /
    • 2023
  • Although we have entered the era of digital transformation, there is currently no system that efficiently collects, manages, integrates, and services a large number of archaeological digital source materials produced as a result of cultural relics research, i.e., an intelligent integrated management and service platform for archaeological academic information. In this regard, the need to build a digital dictionary of Korean archaeology was confirmed by examining the problem of the Digital Encyclopedia of Korean Archaeology, which is currently available in PDF format on the web, the current status of the publication and use of the Dictionary of Korean Archaeology, and the cases of building digital platforms at home and abroad. Therefore, this paper aims to suggest a general direction for creating a digital encyclopedia of Korean archaeology based on the Dictionary of Korean Archaeology, which includes quality knowledge information, to reconsider the accessibility of archaeological data in conformity with data access limitations. The application of the series Dictionary of Korean Archaeology, published since 2001, and the necessity for digital transformation were examined, as well as the application of data from the archaeological data archiving platforms of Europe, the USA, Japan, and cases of establishing platforms corresponding to specialized encyclopedias from Korea. Based on these, a three-step implementation plan and detailed projects were suggested to create the Digital Encyclopedia of Korean Archaeology. Through this, we proposed the design of metadata for computerized records and the expansion to semantic (meaning-based) data that gives and shows the relationship information between the produced metadata as the implementation tasks to build the Digital Dictionary of Korean Archaeology. It is hoped that such research will help create an integrated intelligent management and service platform for archaeology, raise awareness, and provide a better understanding of Korean archaeology to the general public.