• Title/Summary/Keyword: Time Management

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Assessment of stream water quality and pollutant discharge loads affected by recycled irrigation in an agricultural watershed using HSPF and a multi-reservoir model (HSPF와 다중 저류지 모형을 이용한 농업지역 순환관개에 의한 하천 수질 및 배출부하 영향 분석)

  • Kyoung-Seok Lee;Dong Hoon Lee;Youngmi Ahn;Joo-Hyon Kang
    • Journal of Wetlands Research
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    • v.25 no.4
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    • pp.297-305
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    • 2023
  • The recycled irrigation is a type of irrigation that uses downstream water to fulfill irrigation demand in the upstream agricultural areas; the used irrigation water returns back to the downstream. The recycled irrigation is advantageous for securing irrigation water for plant growth, but the returned water typically contains high levels of nutrients due to excess nutrients inputs during the agricultural activities, potentially deteriorating stream water quality. Therefore, quantitative assessment on the effect of the recycled irrigation on the stream water quality is required to establish strategies for effective irrigation water supply and water quality management. For this purpose, a watershed model is generally used; however no functions to simulate the effects of the recycled irrigation are provided in the existing watershed models. In this study, we used multi-reservoir model coupled with the Hydrological Simulation Program-Fortran (HSPF) to estimate the effect of the recycled irrigation on the stream water quality. The study area was the Gwangok stream watershed, a subwatershed of Gyeseong stream watershed in Changnyeong county, Gyeongsangnam-do. The HSPF model was built, calibrated, and used to produce time series data of flow and water quality, which were used as hypothetical observation data to calibrate the multi-reservoir model. The calibrated multi-reservoir model was used for simulating the recycled irrigation. In the multi-reservoir model, the Gwangok watershed consisted of two subsystems, irrigation and the Gwangok stream, and the reactions (plant uptake, adsorption, desorption, and decay) within each subsystem, and fluxes of water and materials between the subsystems, were modeled. Using the developed model, three scenarios with different combinations of the operating conditions of the recycled irrigation were evaluated for their effects on the stream water quality.

Prediction of Spring Flowering Timing in Forested Area in 2023 (산림지역에서의 2023년 봄철 꽃나무 개화시기 예측)

  • Jihee Seo;Sukyung Kim;Hyun Seok Kim;Junghwa Chun;Myoungsoo Won;Keunchang Jang
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.25 no.4
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    • pp.427-435
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    • 2023
  • Changes in flowering time due to weather fluctuations impact plant growth and ecosystem dynamics. Accurate prediction of flowering timing is crucial for effective forest ecosystem management. This study uses a process-based model to predict flowering timing in 2023 for five major tree species in Korean forests. Models are developed based on nine years (2009-2017) of flowering data for Abeliophyllum distichum, Robinia pseudoacacia, Rhododendron schlippenbachii, Rhododendron yedoense f. poukhanense, and Sorbus commixta, distributed across 28 regions in the country, including mountains. Weather data from the Automatic Mountain Meteorology Observation System (AMOS) and the Korea Meteorological Administration (KMA) are utilized as inputs for the models. The Single Triangle Degree Days (STDD) and Growing Degree Days (GDD) models, known for their superior performance, are employed to predict flowering dates. Daily temperature readings at a 1 km spatial resolution are obtained by merging AMOS and KMA data. To improve prediction accuracy nationwide, random forest machine learning is used to generate region-specific correction coefficients. Applying these coefficients results in minimal prediction errors, particularly for Abeliophyllum distichum, Robinia pseudoacacia, and Rhododendron schlippenbachii, with root mean square errors (RMSEs) of 1.2, 0.6, and 1.2 days, respectively. Model performance is evaluated using ten random sampling tests per species, selecting the model with the highest R2. The models with applied correction coefficients achieve R2 values ranging from 0.07 to 0.7, except for Sorbus commixta, and exhibit a final explanatory power of 0.75-0.9. This study provides valuable insights into seasonal changes in plant phenology, aiding in identifying honey harvesting seasons affected by abnormal weather conditions, such as those of Robinia pseudoacacia. Detailed information on flowering timing for various plant species and regions enhances understanding of the climate-plant phenology relationship.

Satellite-Based Cabbage and Radish Yield Prediction Using Deep Learning in Kangwon-do (딥러닝을 활용한 위성영상 기반의 강원도 지역의 배추와 무 수확량 예측)

  • Hyebin Park;Yejin Lee;Seonyoung Park
    • Korean Journal of Remote Sensing
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    • v.39 no.5_3
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    • pp.1031-1042
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    • 2023
  • In this study, a deep learning model was developed to predict the yield of cabbage and radish, one of the five major supply and demand management vegetables, using satellite images of Landsat 8. To predict the yield of cabbage and radish in Gangwon-do from 2015 to 2020, satellite images from June to September, the growing period of cabbage and radish, were used. Normalized difference vegetation index, enhanced vegetation index, lead area index, and land surface temperature were employed in this study as input data for the yield model. Crop yields can be effectively predicted using satellite images because satellites collect continuous spatiotemporal data on the global environment. Based on the model developed previous study, a model designed for input data was proposed in this study. Using time series satellite images, convolutional neural network, a deep learning model, was used to predict crop yield. Landsat 8 provides images every 16 days, but it is difficult to acquire images especially in summer due to the influence of weather such as clouds. As a result, yield prediction was conducted by splitting June to July into one part and August to September into two. Yield prediction was performed using a machine learning approach and reference models , and modeling performance was compared. The model's performance and early predictability were assessed using year-by-year cross-validation and early prediction. The findings of this study could be applied as basic studies to predict the yield of field crops in Korea.

Monitoring and Preventive Preservation of Cultural Heritages to Maintain Original Wooden Architectural Cultural Heritage (목조건축문화재 원형유지를 위한 문화재돌봄 모니터링과 예방보존)

  • CHUN Kyoungmee
    • Korean Journal of Heritage: History & Science
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    • v.56 no.4
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    • pp.192-214
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    • 2023
  • Wooden architectural cultural heritages are one of the visible legacies that show the national's identity. Even when the concept of 'the original' of cultural heritages was not accurately understood, the emphasis of preservation and management of cultural heritages was placed on 'preservation of the original form' or 'maintenance of the original form'. Moreover, these days, following the trend of international preservation principles, cultural heritages are considered important as "values as historical objects." This paper is the result of an attempt to determine the scope and content of what parts should be monitored to maintain the original form of wooden architectural cultural heritage. The first thing to be done in monitoring wooden architectural cultural heritage is to check the condition of the ground and foundation. The second is the column. This is because the instability of the column causes damage to the joint with each member and the fitting part, resulting in physical changes leading to damage to the wall. The third is monitor the roof tiles. If the leak continues into the building due to the separation or damage of the roof, the defect should be partially dismantled and repaired, so it should be monitored to maintain its original shape as much as possible. The monitoring range of the base, column, and roof serves as a reference point for identifying what damage is being done to the relevant cultural heritages. In other words, the data at the time when monitoring began becomes the 'original' for the year. Alternatives based on the analysis of monitoring for the preservation of original cultural heritages should be actively introduced. In addition, by sharing the current state and situation of cultural heritages as a result of monitoring with various related organizations, preventive preservation should be established rather than preservation of cultural heritages by "intervention."

A Study on the Social Venture Startup Phenomenon Using the Grounded Theory Approach (근거이론 접근법을 이용한 소셜벤처 창업 현상에 관한 고찰)

  • Seol, Byung Moon;Kim, Young Lag
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.18 no.1
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    • pp.67-83
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    • 2023
  • The social venture start-up phenomenon is found from the perspectives of social enterprise and for-profit enterprise. This study aims to fundamentally explore the start-up phenomenon of social ventures from these two perspectives. Considering the lack of prior research that researched both social and commercial perspectives at the same time, this paper analyzed using grounded theory approach of Strauss & Corbin(1998), an inductive research method that analyzes based on prior research and interview data. In order to collect data for this study, eight corporate representatives currently operating social ventures were interviewed and data and phenomena were analyzed. This progressed to a theoretical saturation where no additional information was derived. The analysis results of this study using the grounded theory approach are as follows. As a result of open coding and axial coding, 147 concepts and 70 subcategories were derived, and 18 categories were derived through the final abstraction process. In the selective coding, 'expansion of social venture entry in the social domain' and 'expansion of social function of for-profit companies' were selected as key categories, and a story line was formed around this. In this study, we saw that it is necessary to conduct academic research and analysis on the competitive factors required for companies that pursue the values of two conflicting relationships, such as social ventures, to survive with competitiveness. In practice, concepts such as collaboration with for-profit companies, value combination, entrepreneurship competency and performance improvement, social value execution competency reinforcement, communication strategy, for-profit enterprise value investment, and entrepreneur management competency were derived. This study explains the social venture phenomenon for social enterprises, commercial enterprises, and entrepreneurs who want to enter the social venture field. It is expected to provide the implications necessary for successful social venture startups.

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Exploring the Model of Social Enterprise in Sport: Focused on Organization Form(Type) and Task (스포츠 분야 사회적기업의 모델 탐색: 조직형태 및 과제)

  • Sang-Hyun Park;Joo-Young Park
    • Journal of Industrial Convergence
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    • v.22 no.2
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    • pp.73-83
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    • 2024
  • The purpose of this study is to diagnose various problems arising around social enterprises in the sport field from the perspective of the organization and derive necessary tasks and implications. In order to achieve the purpose of the study, the study was largely divided into three stages, and the results were derived. First, the main status and characteristics of social enterprises in the sport field were examined. The current status was analyzed focusing on aspects such as background and origin, legislation and policy, organizational goals, organizational structure and procedures, and organizational characteristics. Social enterprises in the sport sector were in their early stages, and the government's social enterprise policy goal tended to focus on increasing the number of social enterprises in a short period of time through financial input. In addition, it was found that most individual companies rely on government subsidy support due to insufficient profit generation capacity. In the second stage, we focused on the situational factors that affect the functional performance of social enterprises in the sport field. As a result of reviewing the value, ideology, technology, and history of the organization, which are situational factors, it was derived that when certified as a social enterprise in the sport field and supported by the central government or local governments, political control is strong to some extent and exposure to the market is not severe. In the last third step, tasks and implications were derived to form an appropriate organization for social enterprises in the sport field. After the social enterprise ecosystem in the sport sector has been established to some extent, it is necessary to gradually move from the current "government-type" organization to the "national enterprise" organization. This is true in light of the government's limited financial level, not in the short term, but in order for the organization of social enterprises in the sports sector to survive in the long term.

An Analysis of Accessibility to Hydrogen Charging Stations in Seoul Based on Location-Allocation Models (입지배분모형 기반의 서울시 수소충전소 접근성 분석)

  • Sang-Gyoon Kim;Jong-Seok Won;Yong-Beom Pyeon;Min-Kyung Cho
    • Journal of the Society of Disaster Information
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    • v.20 no.2
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    • pp.339-350
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    • 2024
  • Purpose: This study analyzes accessibility of 10 hydrogen charging stations in Seoul and identifies areas that were difficult to access. The purpose is to re-analyze accessibility by adding a new location in terms of equity and safety of location placement, and then draw implications by comparing the improvement effects. Method: By applying the location-allocation model and the service area model based on network analysis of the ArcGIS program, areas with weak access were identified. The location selection method applied the 'Minimize Facilities' method in consideration of the need for rapid arrival to insufficient hydrogen charging stations. The limit distance for arrival within a specific time was analyzed by applying the average vehicle traffic speed(23.1km/h, Seoul Open Data Square) in 2022 to three categories: 3,850m(10minutes), 5,775m(15minutes), 7,700m(20minutes). In order to minimize conflicts over the installation of hydrogen charging stations, special standards of the Ministry of Trade, Industry and Energy applied to derive candidate sites for additional installation of hydrogen charging stations among existing gas stations and LPG/CNG charging stations. Result: As a result of the analysis, it was confirmed that accessibility was significantly improved by installing 5 new hydrogen charging stations at relatively safe gas stations and LPG/CNG charging stations in areas where access to the existing 10 hydrogen charging stations is weak within 20 minutes. Nevertheless, it was found that there are still areas where access remains difficult. Conclusion: The location allocation model is used to identify areas where access to hydrogen charging stations is difficult and prioritize installation, decision-making to select locations for hydrogen charging stations based on scientific evidence can be supported.

Buddhist Sculptures from Seongbulsa Temple in Hwanghae-do Province as Seen through Gelatin Dry Plates and Archival Materials from the Collection of the National Museum of Korea (국립중앙박물관 소장 유리건판과 기록자료로 본 황해도 성불사(成佛寺)의 불교조각)

  • Heo Hyeonguk
    • Bangmulgwan gwa yeongu (The National Museum of Korea Journal)
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    • v.1
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    • pp.278-305
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    • 2024
  • Gelatin dry plate photographs dating to the Japanese colonial era and the official documents from the Japanese Government-General of Korea Museum in the collection of the National Museum of Korea are significant materials documenting cultural heritage in North Korea before it was severely damaged in 1950 during the Korean War. There has been an increase in recent years in studies of Buddhist sculptures in North Korea based on these photographs and documents. This paper presents some new comments on the Buddhist sculptures at Seongbulsa Temple in Hwangju, one of the most famous temples in Hwanghae-do Province, based on the related existing research outcomes. This paper aims to facilitate a more comprehensive understanding of the Buddhist sculptures at Seongbulsa Temple by chronicling its history based on historical records, examining its current status, and exploring in detail the production dates and backgrounds of the Buddhist sculptures featured on gelatin dry plates. Prior to Korea's liberation from Japan in 1945, Seongbulsa housed at least seven sculptural items: two Bodhisattva statues, four Buddha statues, and a triad. Two items are from the early Goryeo period, one is from the late Goryeo period, three are from the early Joseon period, and one is from the late Joseon period. Among them, two surviving items are noteworthy. One is the early Goryeo-era Stone Seated Bhaishajyaguru Buddha photographed in Eungjinjeon Hall at Seongbulsa Temple. A close examination of a schematic drawing of the sculpture's pedestal made at the time it was photographed reveals that its material accords with the materials used for the headless Stone Seated Bhaishajyaguru Buddha and pedestal currently found in the old Sangwonam Hermitage site in the Inner Geumgang Valley of Jeongbangsan Mountain. This accordance could mean that the statue is a new significant example of early Goryeo Buddhist sculpture in North Korea. The other notable sculpture is the Gilt-bronze Seated Amitabha Buddha Triad created in 1454 (the second year of the reign of King Danjong) and discovered in Geungnakjeon Hall at Seongbulsa. This statue is currently in the collection of the Sariwon History Museum in Hwanghae-do Province. It is an important example of a dated small gilt-bronze Buddhist statue from the early Joseon period found in North Korea. This paper is a case study of Buddhist sculptures in North Korea, focusing on Seongbulsa Temple. Further utilization of the National Museum of Korea's gelatin dry plates will contribute to developing the study of the history of Korean Buddhist sculpture.

The Public Health Welfare Conception of the Beveridge Report and Its Realization via the NHS (베버리지 보고서의 의료보장 구상과 NHS를 통한 구현)

  • Juneyoub Han;Jiyong Park
    • The Korean Society of Law and Medicine
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    • v.24 no.3
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    • pp.59-104
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    • 2023
  • This essay attempts to analyze the public health welfare conception within the text of the Beveridge Report and its realization via the NHS in Great Britain. Once referring to the influence of the Report to create the foundations of the 20th-century welfare system, the quest to scrutinize the original intentions of the Report and its succession to the NHS is certainly intriguing. Furthermore, when regarding the significance of public health policy for a modern state, the effort to engage in Beveridge's conception and its realization is more than timely. In light of such a premise, this paper indulges in its study by the following methods. First, the historical background of the Report - namely, the role of the spirit of the age and the experience of the Emergency Medical Service are to be analyzed to identify the origins of the welfare policies proposed by Beveridge. Furthermore, the public health welfare conception of the Report conceived from its time is reflected upon by engaging on the goal towards social welfare and public health scheme. Lastly, the aims of the NHS and its management, treatment classification, and rehabilitation program are reviewed for comparative analysis with the Report to survey the realization of Beveridge's design. In this process, this paper not only takes into account the original text of the Report - but also other essential works of law and public policy, including the NHS Constitution for England and the National Health Service Act of 1946. The intentions of this study are not bound by merely coinciding with the Report, but resonate significance via reflecting upon the Beveridgian legacy on the modern welfare state from the current perspective. The structured analysis to research the aims and policies of the Report and to compare them to the reality of the NHS may provide an opportunity to confirm the realization of Beveridge's scheme in British society. In addition, this essay is part of an academic endeavor to critically assess the past and the present of the welfare institution in the public health sector. As such, it is hopeful that the essay sheds light on further studies concerning the constructive remedies of the Korean welfare system as well.

A Study on the Continuous Usage Intention Factors of O2O Service (O2O 서비스의 지속사용의도에 미치는 영향요인 연구)

  • Sung Yong Jung;Jin Soo Kim
    • Information Systems Review
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    • v.20 no.4
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    • pp.1-23
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    • 2018
  • A smart phone has been widely spread around world and makes people enjoy online shopping in any time and any place. Recently it also changes the distribution environment. O2O (Online-to-Offline) service becomes new normal due to its convenience of ease shopping of product and services. O2O service market shows steady and steep growth, It is reported that, however, 80% of the businesses has been discontinued within the first year because of unstable business models, customer dissatisfaction and distrust of service. Therefore, it is very important research issue to find out influential factors promoting continuous usage intention of O2O service. Previous study shows that it only considers online characteristics and lack of analysis about offline characteristics and social impact factors. The purpose of this paper is to find out continuous usage intention factors of O2O services by literature review, case analysis, and empirical test. A comprehensive research model and related hypothesis are developed and tested by using a structural equation, Survey was carried out among users who have used O2O service including payment service for at least once. Finally 611 samples are selected out of total 813 surveys. The result shows that the model is theoretically proved and 12 out of 17 hypotheses are accepted. The contribution of this paper is that it provides a new theoretical research model about continuous usage intention factors as well as practical guidelines about promoting continuous usage and growth strategies of O2O service.