• Title/Summary/Keyword: Uncertainty

Search Result 7,016, Processing Time 0.034 seconds

Uncertainties of SO2 Vertical Column Density Retrieval from Ground-based Hyper-spectral UV Sensor Based on Direct Sun Measurement Geometry (지상관측 기반 태양 직달광 관측장비의 초분광 자외센서로부터 이산화황 연직칼럼농도의 불확실성 분석 연구)

  • Kang, Hyeongwoo;Park, Junsung;Yang, Jiwon;Choi, Wonei;Kim, Daewon;Lee, Hanlim
    • Korean Journal of Remote Sensing
    • /
    • v.35 no.2
    • /
    • pp.289-298
    • /
    • 2019
  • In this present study, the effects of Signal to Noise Ratio (SNR), Full Width Half Maximum (FWHM), Aerosol Optical Depth (AOD), $O_3$ Vertical Column Density ($O_3$ VCD), and Solar Zenith Angle (SZA) on the accuracy of sulfur dioxide Vertical Column Density ($SO_2$ VCD) retrieval have been quantified using the Differential Optical Absorption Spectroscopy (DOAS) method with the ground-based direct-sun synthetic radiances. The synthetic radiances produced based on the Beer-Lambert-Bouguer law without consideration of the diffuse effect. In the SNR condition of 650 (1300) with FWHM = 0.6 nm, AOD = 0.2, $O_3$ VCD = 300 DU, and $SZA=30^{\circ}$, the Absolute Percentage Difference (APD) between the true $SO_2$ VCD values and those retrieved ranges from 80% (28%) to 16% (5%) for the $SO_2$ VCD of $8.1{\times}10^{15}$ and $2.7{\times}10^{16}molecules\;cm^{-2}$, respectively. For an FWHM of 0.2 nm (1.0 nm) with the $SO_2$ VCD values equal to or greater than $2.7{\times}10^{16}molecules\;cm^{-2}$, the APD ranges from 6.4% (29%) to 6.2% (10%). Additionally, when FWHM, SZA, AOD, and $O_3$ VCD values increase, APDs tend to be large. On the other hand, SNR values increase, APDs are found to decrease. Eventually, it is revealed that the effects of FWHM and SZA on $SO_2$ VCD retrieval accuracy are larger than those of $O_3$ VCD and AOD. The SZA effects on the reduction of $SO_2$ VCD retrieval accuracy is found to be dominant over the that of FWHM for the condition of $SO_2$ VCD larger than $2.7{\times}10^{16}molecules\;cm^{-2}$.

Analysis of Climate Change Adaptation Researches Related to Health in South Korea (한국의 건강 분야 기후변화적응 연구동향 분석)

  • Ha, Jongsik
    • Journal of Climate Change Research
    • /
    • v.5 no.2
    • /
    • pp.139-151
    • /
    • 2014
  • It is increasingly supported by scientific evidence that greenhouse gas caused by human activities is changing the global climate. In particular, the changing climate has affected human health, directly or indirectly, and its adverse impacts are estimated to increase in the future. In response, many countries have established and implemented a variety of mitigation and adaptation measures. However, it is significant to note that climate change will continue over the next few centuries and its impacts on human health should be tackled urgently. The purpose of this paper is to examine domestic policies and research in health sector in adaptation to climate change. It further aims to recommend future research directions for enhanced response to climate change in public health sector, by reviewing a series of adaptation policies in the selected countries and taking into account the general features of health adaptation policies. In this regard, this study first evaluates the current adaptation policies in public health sector by examining the National Climate Change Adaptation Master Plan(2011~2015) and Comprehensive Plan for Environment and Health(2011~2020) and reviewing research to date of the government and relevant institutions. For the literature review, two information service systems are used: namely, the National Science and Technology Information Service(NTIS) and the Policy Research Information Service & Management(PRISM). Secondly, a series of foreign adaptation policies are selected based on the global research priorities set by WHO (2009) and reviewed in order to draw implications for domestic research. Finally, the barriers or constraints in establishing and implementing health adaptation policies are analyzed qualitatively, considering the general characteristics of adaptation in the health sector to climate change, which include uncertainty, finance, technology, institutions, and public awareness. This study provides four major recommendations: to mainstream health sector in the field of adaptation policy and research; to integrate cross-sectoral adaptation measures with an aim to the improvement of health and well-being of the society; to enhance the adaptation measures based on evidence and cost-effectiveness analysis; and to facilitate systemization in health adaptation through setting the key players and the agenda.

Prediction of a hit drama with a pattern analysis on early viewing ratings (초기 시청시간 패턴 분석을 통한 대흥행 드라마 예측)

  • Nam, Kihwan;Seong, Nohyoon
    • Journal of Intelligence and Information Systems
    • /
    • v.24 no.4
    • /
    • pp.33-49
    • /
    • 2018
  • The impact of TV Drama success on TV Rating and the channel promotion effectiveness is very high. The cultural and business impact has been also demonstrated through the Korean Wave. Therefore, the early prediction of the blockbuster success of TV Drama is very important from the strategic perspective of the media industry. Previous studies have tried to predict the audience ratings and success of drama based on various methods. However, most of the studies have made simple predictions using intuitive methods such as the main actor and time zone. These studies have limitations in predicting. In this study, we propose a model for predicting the popularity of drama by analyzing the customer's viewing pattern based on various theories. This is not only a theoretical contribution but also has a contribution from the practical point of view that can be used in actual broadcasting companies. In this study, we collected data of 280 TV mini-series dramas, broadcasted over the terrestrial channels for 10 years from 2003 to 2012. From the data, we selected the most highly ranked and the least highly ranked 45 TV drama and analyzed the viewing patterns of them by 11-step. The various assumptions and conditions for modeling are based on existing studies, or by the opinions of actual broadcasters and by data mining techniques. Then, we developed a prediction model by measuring the viewing-time distance (difference) using Euclidean and Correlation method, which is termed in our study similarity (the sum of distance). Through the similarity measure, we predicted the success of dramas from the viewer's initial viewing-time pattern distribution using 1~5 episodes. In order to confirm that the model is shaken according to the measurement method, various distance measurement methods were applied and the model was checked for its dryness. And when the model was established, we could make a more predictive model using a grid search. Furthermore, we classified the viewers who had watched TV drama more than 70% of the total airtime as the "passionate viewer" when a new drama is broadcasted. Then we compared the drama's passionate viewer percentage the most highly ranked and the least highly ranked dramas. So that we can determine the possibility of blockbuster TV mini-series. We find that the initial viewing-time pattern is the key factor for the prediction of blockbuster dramas. From our model, block-buster dramas were correctly classified with the 75.47% accuracy with the initial viewing-time pattern analysis. This paper shows high prediction rate while suggesting audience rating method different from existing ones. Currently, broadcasters rely heavily on some famous actors called so-called star systems, so they are in more severe competition than ever due to rising production costs of broadcasting programs, long-term recession, aggressive investment in comprehensive programming channels and large corporations. Everyone is in a financially difficult situation. The basic revenue model of these broadcasters is advertising, and the execution of advertising is based on audience rating as a basic index. In the drama, there is uncertainty in the drama market that it is difficult to forecast the demand due to the nature of the commodity, while the drama market has a high financial contribution in the success of various contents of the broadcasting company. Therefore, to minimize the risk of failure. Thus, by analyzing the distribution of the first-time viewing time, it can be a practical help to establish a response strategy (organization/ marketing/story change, etc.) of the related company. Also, in this paper, we found that the behavior of the audience is crucial to the success of the program. In this paper, we define TV viewing as a measure of how enthusiastically watching TV is watched. We can predict the success of the program successfully by calculating the loyalty of the customer with the hot blood. This way of calculating loyalty can also be used to calculate loyalty to various platforms. It can also be used for marketing programs such as highlights, script previews, making movies, characters, games, and other marketing projects.

Exploring the Factors Influencing on the Accuracy of Self-Reported Responses in Affective Assessment of Science (과학과 자기보고식 정의적 영역 평가의 정확성에 영향을 주는 요소 탐색)

  • Chung, Sue-Im;Shin, Donghee
    • Journal of The Korean Association For Science Education
    • /
    • v.39 no.3
    • /
    • pp.363-377
    • /
    • 2019
  • This study reveals the aspects of subjectivity in the test results in a science-specific aspect when assessing science-related affective characteristic through self-report items. The science-specific response was defined as the response that appear due to student's recognition of nature or characteristics of science when his or her concepts or perceptions about science were attempted to measure. We have searched for cases where science-specific responses especially interfere with the measurement objective or accurate self-reports. The results of the error due to the science-specific factors were derived from the quantitative data of 649 students in the 1st and 2nd grade of high school and the qualitative data of 44 students interviewed. The perspective of science and the characteristics of science that students internalize from everyday life and science learning experiences interact with the items that form the test tool. As a result, it was found that there were obstacles to accurate self-report in three aspects: characteristics of science, personal science experience, and science in tool. In terms of the characteristic of science in relation to the essential aspect of science, students respond to items regardless of the measuring constructs, because of their views and perceived characteristics of science based on subjective recognition. The personal science experience factor representing the learner side consists of student's science motivation, interaction with science experience, and perception of science and life. Finally, from the instrumental point of view, science in tool leads to terminological confusion due to the uncertainty of science concepts and results in a distance from accurate self-report eventually. Implications from the results of the study are as follows: review of inclusion of science-specific factors, precaution to clarify the concept of measurement, check of science specificity factors at the development stage, and efforts to cross the boundaries between everyday science and school science.

Illness Experiences and Palliative Care Needs in Community Dwelling Persons with Cardiometabolic Diseases (심혈관대사질환이 있는 지역사회 거주 환자의 질환경험 및 완화의료 요구)

  • Cha, EunSeok;Lee, JaeHwan;Lee, KangWook;Hwang, Yujin
    • Journal of Hospice and Palliative Care
    • /
    • v.22 no.1
    • /
    • pp.8-18
    • /
    • 2019
  • Purpose: This study was conducted to better understand the illness experiences and palliative care needs in community-dwelling persons with cardiometabolic diseases. Methods: This qualitative descriptive study was conducted with 11 patients (and three family members) among 28 patients contacted. Interviews were led by the principal investigator in her office or at participants' home depending on their preference. All interviews were digitally recorded and transcribed by a research assistant. The interviews were analyzed by two independent researchers using a conventional method. Results: Participants' ages ranged from 42 to 82 years (nine men and two women). Three themes were identified: (1) same disease, but different illness experiences; (2) I am in charge of my disease(s); (3) preparation for disease progression. Participants were informed of the name of their disease when they were diagnosed, but not provided with explanation of the diagnosis or meant or how to do self-care to delay the disease progression, which increased the feelings of uncertainty, hopelessness and anxiety. Taking medication was considered to be the primary treatment option and self-care a supplemental one. Advanced care plans were considered when they felt the progression of their disease(s) while refraining from sharing it with their family or health care professionals to save their concerns. All participants were willing to withhold life-sustaining treatment without making any preparation in writing. Conclusion: Education on self-care and advanced care planning should be provided to community-dwelling persons with cardiometabolic diseases. A patient-centered education program needs to be developed for this population.

The Applicability of Conditional Generative Model Generating Groundwater Level Fluctuation Corresponding to Precipitation Pattern (조건부 생성모델을 이용한 강수 패턴에 따른 지하수위 생성 및 이의 활용에 관한 연구)

  • Jeong, Jiho;Jeong, Jina;Lee, Byung Sun;Song, Sung-Ho
    • Economic and Environmental Geology
    • /
    • v.54 no.1
    • /
    • pp.77-89
    • /
    • 2021
  • In this study, a method has been proposed to improve the performance of hydraulic property estimation model developed by Jeong et al. (2020). In their study, low-dimensional features of the annual groundwater level (GWL) fluctuation patterns extracted based on a Denoising autoencoder (DAE) was used to develop a regression model for predicting hydraulic properties of an aquifer. However, low-dimensional features of the DAE are highly dependent on the precipitation pattern even if the GWL is monitored at the same location, causing uncertainty in hydraulic property estimation of the regression model. To solve the above problem, a process for generating the GWL fluctuation pattern for conditioning the precipitation is proposed based on a conditional variational autoencoder (CVAE). The CVAE trains a statistical relationship between GWL fluctuation and precipitation pattern. The actual GWL and precipitation data monitored on a total of 71 monitoring stations over 10 years in South Korea was applied to validate the effect of using CVAE. As a result, the trained CVAE model reasonably generated GWL fluctuation pattern with the conditioning of various precipitation patterns for all the monitoring locations. Based on the trained CVAE model, the low-dimensional features of the GWL fluctuation pattern without interference of different precipitation patterns were extracted for all monitoring stations, and they were compared to the features extracted based on the DAE. Consequently, it can be confirmed that the statistical consistency of the features extracted using CVAE is improved compared to DAE. Thus, we conclude that the proposed method may be useful in extracting a more accurate feature of GWL fluctuation pattern affected solely by hydraulic characteristics of the aquifer, which would be followed by the improved performance of the previously developed regression model.

The Study on the Effect of Target Volume in DQA based on MLC log file (MLC 로그 파일 기반 DQA에서 타깃 용적에 따른 영향 연구)

  • Shin, Dong Jin;Jung, Dong Min;Cho, Kang Chul;Kim, Ji Hoon;Yoon, Jong Won;Cho, Jeong Hee
    • The Journal of Korean Society for Radiation Therapy
    • /
    • v.32
    • /
    • pp.53-59
    • /
    • 2020
  • Purpose: The purpose of this study is to compare and analyze the difference between the MLC log file-based software (Mobius) and the conventional phantom-ionization chamber (ArcCheck) dose verification method according to the change of target volume. Material and method: Radius 0.25cm, 0.5cm, 1cm, 2cm, 3cm, 4cm, 5cm, 6cm, 7cm, 8cm, 9cm, 10cm with a Sphere-shaped target Twelve plans were created and dose verification using Mobius and ArcCheck was conducted three times each. The irradiated data were compared and analyzed using the point dose error value and the gamma passing rate (3%/3mm) as evaluation indicators. Result: Mobius point dose error values were -9.87% at a radius of 0.25cm and -4.39% at 0.5cm, and the error value was within 3% at the remaining target volume. The gamma passing rate was 95% at a radius of 9cm and 93.9% at 10cm, and a passing rate of more than 95% was shown in the remaining target volume. In ArcCheck, the average error value of the point dose was about 2% in all target volumes. The gamma passing rate also showed a pass rate of 98% or more in all target volumes. Conclusion: For small targets with a radius of 0.5cm or less or a large target with a radius of 9cm or more, considering the uncertainty of DQA based on MLC log files, phantom-ionized DQA is used in complementary ways to include point dose, gamma index, DVH, and target coverage. It is believed that it is desirable to verify the dose delivery through a comprehensive analysis.

Vietnam in 2016: The Situations and Prospects of Politics, Economy, and International Relations (베트남 2016: 정치, 경제, 대외관계의 현황과 전망)

  • LEE, Han Woo;CHAE, Su Hong
    • The Southeast Asian review
    • /
    • v.27 no.1
    • /
    • pp.163-191
    • /
    • 2017
  • This article aims to review the recent, especially focusing on the year of 2016, situations and prospects of the Vietnamese politics, economy, and international relations. Politically, Vietnam completed the election of members for the National Assembly and organized new leadership at the 12th National Congress of the Vietnamese Communist Party in 2016. One characteristic of the new leadership is that the politicians, especially the members of politburo, from the North continue to occupy the position of majority. The other one is that the new leadership promised to carry out the restructuring of economy toward industries producing higher value-added commodities even though Vietnam industries admittedly need to accelerate present industrialization and modernization as a developing country under the seemingly contradictory slogan of "the development of market economy for socialism." The declared goals of the new leadership in Vietnam are inevitable in a sense since the development of Vietnamese economy has been heavily dependent upon Foreign Direct Investment(FDI) taking advantage of Vietnamese cheap labor and simultaneously it is evident that its future is unsecure if it maintains status quo. In fact, the Vietnamese economy has impressively showed high growth rate by the help of foreign capitals since 1990s despite the repetitive recessions of global economy but its growth is not likely to be sustainable anymore if it will not reduce foreign dependency and social economic inequality in a long term. In a short run, global economic recession, the financial and monetary policies of global powers, and recent protectionism and uncertainty of trade agreements will be three crucial variables to affect Vietnamese economy. In terms of international relations, Vietnam is continuously expected to practise the policy of checks and balances among the powerful countries. Vietnam has seriously disputed with China on islands sovereignty in the South China Sea and attempted to maintain close relationship with other powerful countries including especially America. However, mainly due to the new protectionism by the regime of American president Donald Trump, the Vietnamese government also need to keep close relationship with China increasingly for both economic and diplomatic security. Under the circumstances, Vietnam is expected to maintain more practical and balanced international relations.

Thailand in 2016: The Death of King Bhumibol Adulyadej and the Uncertainty in Political Economy (태국 2016: 푸미폰 국왕의 서거와 정치·경제적 불확실성)

  • KIM, Hong Koo;LEE, Mi Ji
    • The Southeast Asian review
    • /
    • v.27 no.2
    • /
    • pp.245-271
    • /
    • 2017
  • The purpose of this study is to examine and assess the major characteristics and changes of politics, economy, and diplomacy in Thailand in 2016. Specifically, it reviewed the New Constitution that was passed in 2016, the confrontation between different political forces and the trend of military regime around the New Constitution, and the political instability caused by the accession of the new king to the throne. This study also set out to figure out changes to the economy and foreign relations of the country, including its relations with South Korea, under the military regime and make predictions for the impact and future prospects of King Bhumibol Adulyadej's death on the politics and economy of the country. In 2016, the politics of Thailand took a step further toward the transfer of power to civil government and established a foundation for an authoritarian system. The draft of the New Constitution, which does not seem to be democratic, was approved by a referendum and enabled the military authorities to continue their political interventions, even after the general election. The New Constitution, in particular, reduces the power of political parties itself in addition to simply keeping the Thaksin's party in check; thus, anticipating ongoing conflicts between the military authorities and political parties. In this situation, the absence of King Bhumibol Adulyadej, who used to play a decisive role in promoting the political stability of the country, and the accession of the new king to the throne raise concerns about the acceleration of political instability, which has continued after the coup and influenced the diplomatic relations of the country. Today, Thailand is distancing itself from Western nations that do not recognize the current military regime including the U.S.A. and EU member states and instead maintains a rapidly friendly and close relation with China. In 2016, the economy of Thailand made a gradual recovery rather than high growth. The death of King Bhumibol Adulyadej has exerted limited direct economic impacts only on individual consumption and tourism and is not likely to cause a recession. An economic crisis will, however, be unavoidable if the political confrontations escalate before the general election to transfer power to the civil government.

A Proposal for Korean armed forces preparing toward Future war: Examine the U.S. 'Mosaic Warfare' Concept (미래전을 대비한 한국군 발전방향 제언: 미국의 모자이크전 수행개념 고찰을 통하여)

  • Chang, Jin O;Jung, Jae-young
    • Maritime Security
    • /
    • v.1 no.1
    • /
    • pp.215-240
    • /
    • 2020
  • In 2017, the U.S. DARPA coined 'mosaic warfare' as a new way of warfighting. According to the Timothy Grayson, director of DARPA's Strategic Technologies Office, mosaic warfare is a "system of system" approach to warfghting designed around compatible "tiles" of capabilities, rather than uniquely shaped "puzzle pieces" that must be fitted into a specific slot in a battle plan in order for it to work. Prior to cover mosaic warfare theory and recent development, it deals analyze its background and several premises for better understanding. The U.S. DoD officials might acknowledge the current its forces vulnerability to the China's A2/AD assets. Furthermore, the U.S. seeks to complete military superiority even in other nation's territorial domains including sea and air. Given its rapid combat restoration capability and less manpower casualty, the U.S. would be able to ready to endure war of attrition that requires massive resources. The core concept of mosaic warfare is a "decision centric warfare". To embody this idea, it create adaptability for U.S. forces and complexity or uncertainty for the enemy through the rapid composition and recomposition of a more disag g reg ated U.S. military force using human command and machine control. This allows providing more options to friendly forces and collapse adversary's OODA loop eventually. Adaptable kill web, composable force packages, A.I., and context-centric C3 architecture are crucial elements to implement and carry out mosaic warfare. Recently, CSBA showed an compelling assessment of mosaic warfare simulation. In this wargame, there was a significant differences between traditional and mosaic teams. Mosaic team was able to mount more simultaneous actions, creating additional complexity to adversaries and overwhelming their decision-making with less friendly force's human casualty. It increase the speed of the U.S. force's decision-making, enabling commanders to better employ tempo. Consequently, this article finds out and suggests implications for Korea armed forces. First of all, it needs to examine and develop 'mosaic warfare' in terms of our security circumstance. In response to future warfare, reviewing overall force structure and architecture is required which is able to compose force element regardless domain. In regards to insufficient defense resources and budget, "choice" and "concentration" are also essential. It needs to have eyes on the neighboring countries' development of future war concept carefully.

  • PDF