• Title/Summary/Keyword: Characteristics of Work

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Rheological Characteristics of Hydrogen Fermented Food Waste and Review on the Agitation Intensity (음식물류폐기물 수소 발효액의 유변학적 특성과 교반강도 고찰)

  • Kim, Min-Gyun;Lee, Mo-Kwon;Im, Seong-Won;Shin, Sang-Ryong;Kim, Dong-Hoon
    • Journal of the Korea Organic Resources Recycling Association
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    • v.25 no.4
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    • pp.41-50
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    • 2017
  • The design of proper agitation system is requisite in biological waste treatment and energy generation plant, which is affected by viscosity, impeller types, and power consumption. In the present work, hydrogen fermentation of food waste was conducted at various operational pHs (4.5~6.5) and substrate concentrations (10~50 g Carbo. COD/L), and the viscosity of fermented broth was analyzed. The $H_2$ yield significantly varied from 0.51 to $1.77mol\;H_2/mol\;hexose_{added}$ depending on the pH value, where the highest performance was achieved at pH 5.5. The viscosity gradually dropped with shear rate increase, indicating a shear thinning property. With the disintegration of carbohydrate, the viscosity dropped after fermentation, but it did not change depending on the operational pH. At the same pH level, the $H_2$ yield was not affected much, ranging $1.40{\sim}1.86mol\;H_2/mol\;hexose_{added}$ at 10~50 g Carbo. COD/L. The zero viscosity and infinite viscosity of fermented broth increased with substrate concentrations, from 10.4 to $346.2mPa{\cdot}s$, and from 1.7 to $5.3mPa{\cdot}s$, respectively. There was little difference in the viscosity value of fermented broth at 10 and 20 g Carbo. COD/L. As a result of designing the agitation intensity based on the experimental results, it is expected that the agitation intensity can be reduced during hydrogen fermentation. The initial and final agitation intensity of 30 g Carbo. COD/L in hydrogen fermentation were 26.0 and 10.0 rpm, respectively. As fermentation went on, the viscosity gradually decreased, indicating that the power consumption for agitation of food waste can be reduced.

Retrieval of Vegetation Health Index for the Korean Peninsula Using GK2A AMI (GK2A AMI를 이용한 한반도 식생건강지수 산출)

  • Lee, Soo-Jin;Cho, Jaeil;Ryu, Jae-Hyun;Kim, Nari;Kim, Kwangjin;Sohn, Eunha;Park, Ki-Hong;Jang, Jae-Cheol;Lee, Yangwon
    • Korean Journal of Remote Sensing
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    • v.38 no.2
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    • pp.179-188
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    • 2022
  • Global warming causes climate change and increases extreme weather events worldwide, and the occurrence of heatwaves and droughts is also increasing in Korea. For the monitoring of extreme weather, various satellite data such as LST (Land Surface Temperature), TCI (Temperature Condition Index), NDVI (Normalized Difference Vegetation Index), VCI (Vegetation Condition Index), and VHI (Vegetation Health Index) have been used. VHI, the combination of TCI and VCI, represents the vegetation stress affected by meteorological factors like precipitation and temperature and is frequently used to assess droughts under climate change. TCI and VCI require historical reference values for the LST and NDVI for each date and location. So, it is complicated to produce the VHI from the recent satellite GK2A (Geostationary Korea Multi-Purpose Satellite-2A). This study examined the retrieval of VHI using GK2A AMI (Advanced Meteorological Imager) by referencing the historical data from VIIRS (Visible Infrared Imaging Radiometer Suite) NDVI and LST as a proxy data. We found a close relationship between GK2A and VIIRS data needed for the retrieval of VHI. We produced the TCI, VCI, and VHI for GK2A during 2020-2021 at intervals of 8 days and carried out the interpretations of recent extreme weather events in Korea. GK2A VHI could express the changes in vegetation stress in 2020 due to various extreme weather events such as heatwaves (in March and June) and low temperatures (in April and July), and heavy rainfall (in August), while NOAA (National Oceanic and Atmospheric Administration) VHI could not well represent such characteristics. The GK2A VHI presented in this study can be utilized to monitor the vegetation stress due to heatwaves and droughts if the historical reference values of LST and NDVI can be adjusted in a more statistically significant way in the future work.

Population Strategy for Physical Activity in Korea (우리나라 신체활동 및 운동사업에서의 인구집단 전략)

  • Lee, Moo-Sik
    • Journal of agricultural medicine and community health
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    • v.30 no.2
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    • pp.227-240
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    • 2005
  • Health promotion has more comprehensive approaches in recent years. Nevertheless we accept the concept of health promotion differently, we are agree on that community is the most important field in health promotion which includes population at the aspect of health policy, individual skill and, environment. And there are a number of different approaches to health promotion. In them, 'population approaches' and 'high -risk group approaches' has the most different characteristics. 'Population approaches' is equally important or more important than 'individual approaches' for maintaining and promoting population health. Almost part of this article contents is the summary of the guideline and population strategy of health promotion in Korea, 1999 - 2005. Community based health promotion program should be reinforced, integrated, comprehensive, collaborative through efficiently utilizing community resources. Recent new orientation of community health program is integrated health program, we can find this orientation at Ottawa charter 1986. Comprehensive approaches with the determinant factors for health are essential task. Physical activity is a key health determinant. The population-health approach suggests that educating people about physical activity is not enough. Individual behavior changes are important too, but need to be balanced with strategies for environmental change. Population strategy with physical activity for health promotion should be developed through improving social and physical supportive environment, linking and integrating community resources between public and private sectors in national, regional and local level. Continuous public education and social marketing should be provided through collaborating with community physical activity organization, facilities, work-places and school for increasing concern of all the people of community about physical activity. Governments, agencies and citizens should held and participate to building movement. And the strategy that various 'active for life' program should be developed, delivered, maintained and reinforced continuously. Basically, adequate and sufficient financing, developing human resources, policies and legislation would be provided and supported fully too. At last, research development and knowledge exchange are required domestically and internationally. In Korea, we had classified the category of strategic priority of physical activity programs by environmental support, life-course approach, high-risk group approach and disease group approach for physical activity program based on community health center. Community based core programs for physical activity that includes infrastructure building and establishment of supporting environment, community campaign, health promotion education and public service announcement, physical activity programs for elderly and obesity, exercise prescription program.

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Spatial Distribution of Rice Root under Long-term Chemical and Manure Fertilization in Paddy (화학비료 및 희비 장기시용에 따른 벼 뿌리 분포 특성)

  • 전원태;박창영;조영손;박기도;윤을수;강위금;박성태;최진용
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.48 no.6
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    • pp.484-489
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    • 2003
  • It is well known that root distribution of rice is a crucial factor for nutrient absorbtion and affect by soil fertility management. However, the findings on root distribution are limited due to laborious and tedious work. The characteristics of root distribution were investigated in long-term fertilizer experiment plots that were established in paddy soil, a fine silty family of typic Hal-paqueps (Pyeongtaeg series) in 1967. fertilizer experiment plots of no fertilizer, compost, NPK and NPK+compost plot have been maintained consistently for the past thirty six year and Npk+silicate plot for the past twenty two years. In NPK plot, 150kg N (urea), 100kg -$\textrm{P}_2\textrm{O}_5$ (fused phosphate) and 100kg $\textrm{K}_2\textrm{O}$(potassium chloride) per hectare have been applied. For NPK+silicate plot, 500kg $\textrm{Si}\textrm{O}_2$ (silicate) was applied in addition to fertilizer in NPK plot. For the compost plot, 10,000kg rice straw compost per hectare were applied. Root samples were taken from the positions of hill-center (below hill) and mid-point of four adjacent rice hills at heading stage by cylinder monolith (CM) method. The soil cores were sampled 20cm depth from the soil surface and partitioned four into layers at an interval of 5cm. The soil particles surrounding roots were washed out with tap water, Length and weight of the roots in each soil layer were measured and root length density (RLD), root weight density (RWD), specific root length(SRL) and rooting depth index (RDI) were calculated. Total root length was measured by intersection method. Plant height, tiller and shoot dry weight were the highest in NPK+compost plot. But RLD of hill-center soil cores was the highest in no-fertilizer plots. In the soil cores from mid-point position of four adjacent hills, RLD at 15-20cm soil depth was higher in compost plot than NPK plot. RLD in compost plots showed even distribution compared to those in chemical- fertilizer plots. RWD was the highest in the NPK+compost plot. SRL was the lowest in the NPK+silicate plot. RDI was the highest in the compost plot. Also, in this experiment it was found that the distribution of roots was closely related to the physical properties of the soil as affected by fertilization management.

The Development and Effectiveness of a PBL Based Career Education Program (PBL 기반 진로교육 프로그램의 개발 및 효과검증)

  • Lee, Hye-Suk;Kim, You-Me
    • The Korean Journal of Elementary Counseling
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    • v.8 no.1
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    • pp.33-50
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    • 2009
  • The purpose of this study was to develop a PBL-based career education program and to examine its effectiveness on school children's career maturity. It's specifically meant to prepare a career education program to assist students to get an accurate grip on their aptitude, interest and personality and explore various sorts of occupations in the course of solving authentic and contextual career-related problems. After children's developmental characteristics and needs were analyzed, task analysis was implemented, and the objectives were defined. And then the core of the program, PBL problems were developed, and the validity of the problems were verified Evaluation plans and tools were prepared to assess children's problem-solving process and presentation, and an online learning space was designed. The program that consisted of 10-minute 21 sessions was provided to fifth-grade elementary schoolers for eight weeks. The findings of the study were as follows: The experimental group that participated in the PBL-based career education program showed a more significant improvement than the control group that didn't in career attitude and three career attitude subfactors involving planness, disposition and compromise. And the former made a more significant progress than the latter in career ability and its subfactors including vocational comprehension, self-understanding and decision-making skills as well. As a result of making a content analysis to make up for the survey, the students reported that they were able to get an objective understanding of themselves and acquire diverse and profound knowledge on work and the business world in the middle of solving the given PBL problems related to different areas in group and giving a presentation. In conclusion, a PBL based career education program developed by this researcher encouraged the students to have an objective self-understanding, to have a dynamic interactive discussion with their group members. Therefore the program had a positive impact on boosting the career attitude and career ability of the elementary schoolers. The findings suggested that in the field of elementary career education, autonomous learning attitude and subjecthood are the crucial factors to stimulate school children to explore and create their own future.

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The Sociocultural Characteristics of Korean Ethnics in Central Asia (중앙아시아 한인의 사회문화적 특성과 과제)

  • 정성호
    • Korea journal of population studies
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    • v.20 no.2
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    • pp.161-180
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    • 1997
  • There are about 400, 000 Korean ethnics living in Central Asia. Most of Koreans in Central Asia are leading a stable middle class life mostly engaged in farm work. With increase of educational attainment of their children, a number of Koreans are launching into political and academic circles as well as in the cultural world or the press. In recent years, however, the countries in this area(Uzbekistan and Kazakstan) for this study advocate an ethnic united policy to stabilize the politics and society and to carry out efficient transformation from the former socialistic economy to a market oriented economy. In addition, they are trying to recover the culture and the language of each nation which has been forgotten in the assimilation of Russia policy. Koreans have difficulty in adaption to this kind of change. In fact, a number of Koreans lost traditional culture and could not speak their mother language - Korean. Although they more or less maintain national consciousness, they recognize Uzbekistan or Kazakstan as their nation politically. They associated with North Korea unilaterally before the launching of the Perestroika policy. But after the Seoul Olympics held in 1998, there was movement to know and understand South Korea. There has been increased in the investment by Korean companies in Central Asia. Now, what is an alternative idea for Korean community consciousness\ulcorner It can be summarized as follows: 1) The increase of aid to Korean education institute : Considering the last few decades of Russia's strong racial assimilation policy, which leads most Koreans to lost their language and national culture, the priority should go to Koreans education. 2) Local Korean press support : Though Korean newspaper are published and Korean broadcasting is on the air currently in Uzbekistan and Kazakstan, they are suffering from qualified staff and poor financial status. Therefore, positive support should be established for these Korean mass communication media outlets to recover their own function and expand their dissemination powers quickly. 3) Research on the actual condition for Korean Community : It is essential to directly examine the local Korean community's regional distribution, population structure, Korean group's formation and operation, social and cultural understanding, racial consciousness, hope for their mother land and much more. 4) Increase of mother land and education opportunity : To stir up national culture and national consciousness within the Korean community, it is necessary to expand continuous opportunities for mother land visits and education training for local Koreans, especially for second and third generations.

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Basic Study on Historical Repair Techniques for Landscape Architectural Facilities - Focusing on Government-managed Spaces in Joseon Dynasty - (전통조경 시설물의 역사적 수리기법에 관한 기초연구 - 조선시대 관영공간을 중심으로 -)

  • Kim, Min-Seon;Oh, Jun-Young
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.41 no.4
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    • pp.8-20
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    • 2023
  • Although the landscape architectural facilities need to be repaired according to historical and authentic techniques, the repair criteria of the standard specification for repairing cultural heritages still remain at a theoretical level, and there are little research analyzing detailed techniques from specific cases. This study discussed the repair techniques based on historical facts, around terraced flower beds, ponds, waterways and pavement in the government-managed spaces in the Joseon Dynasty. It analyzed the materials and finish of stone wall elements, the structural reinforcement and backfill materials, and topsoil surface protection measures, and drew out stones for foundation reinforcement, plastering material for agglutination, and stone processing techniques for the terraced flower beds. It examined the materials and structures of the rock revetment, foundation reinforcement and waterproofing techniques and drew out the outstanding characteristics of the foundation work, the recycle of used elements and the management of water quality, for the ponds. It primarily investigated the materials, foundation reinforcement and waterproofing techniques and discovered the repair techniques such as cover stone finishing methods, foundation and backfill materials, and flow reduction methods, for the waterways. Finally, it provided actual cases of the foundation composition, auxiliary materials and tools, and the use of cyperaceae and highlighted the existence of professional craftsmen called Bangjeonjang(方磚匠), for the pavement. This study is expected to be a staring point for discovering the repair techniques for landscape architectural facilities and used as basic data for revising specifications in the future.

A Study on the Application of Block Chain Technology on EVMS (EVMS 업무의 블록체인 기술 적용 방안 연구)

  • Kim, Il-Han;Kwon, Sun-Dong
    • Management & Information Systems Review
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    • v.39 no.2
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    • pp.39-60
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    • 2020
  • Block chain technology is one of the core elements for realizing the 4th industrial revolution, and many efforts have been made by government and companies to provide services based on block chain technology. In this study we analyzed the benefits of block chain technology for EVMS and designed EVMS block chain platform with increased data security and work efficiency for project management data, which are important assets in monitoring progress, foreseeing future events, and managing post-completion. We did the case studies on the benefits of block chain technology and then conducted the survey study on security, reliability, and efficiency of block chain technology, targeting 18 block chain experts and project developers. And then, we interviewed EVMS system operator on the compatibility between block chain technology and EVM Systems. The result of the case studies showed that block chain technology can be applied to financial, logistic, medical, and public services to simplify the insurance claim process and to improve reliability by distributing transaction data storage and applying security·encryption features. Also, our research on the characteristics and necessity of block chain technology in EVMS revealed the improvability of security, reliability, and efficiency of management and distribution of EVMS data. Finally, we designed a network model, a block structure, and a consensus algorithm model and combined them to construct a conceptual block chain model for EVM system. This study has the following contribution. First, we reviewed that the block chain technology is suitable for application in the defense sector and proposed a conceptual model. Second, the effect that can be obtained by applying block chain technology to EVMS was derived, and the possibility of improving the existing business process was derived.

Speech Recognition Using Linear Discriminant Analysis and Common Vector Extraction (선형 판별분석과 공통벡터 추출방법을 이용한 음성인식)

  • 남명우;노승용
    • The Journal of the Acoustical Society of Korea
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    • v.20 no.4
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    • pp.35-41
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    • 2001
  • This paper describes Linear Discriminant Analysis and common vector extraction for speech recognition. Voice signal contains psychological and physiological properties of the speaker as well as dialect differences, acoustical environment effects, and phase differences. For these reasons, the same word spelled out by different speakers can be very different heard. This property of speech signal make it very difficult to extract common properties in the same speech class (word or phoneme). Linear algebra method like BT (Karhunen-Loeve Transformation) is generally used for common properties extraction In the speech signals, but common vector extraction which is suggested by M. Bilginer et at. is used in this paper. The method of M. Bilginer et al. extracts the optimized common vector from the speech signals used for training. And it has 100% recognition accuracy in the trained data which is used for common vector extraction. In spite of these characteristics, the method has some drawback-we cannot use numbers of speech signal for training and the discriminant information among common vectors is not defined. This paper suggests advanced method which can reduce error rate by maximizing the discriminant information among common vectors. And novel method to normalize the size of common vector also added. The result shows improved performance of algorithm and better recognition accuracy of 2% than conventional method.

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Developmental Standard of the Short Sensory Profile for Korean Children of School Age (7 to 9 years old) (만 7~9세 학령기아동의 감각통합 임상관찰평가의 발달기준에 관한 일연구)

  • Ji, Seok-Yeon;Kim, Mi-Sun;Keum, Hyo-Jin;Kim, Sung-Hee
    • The Journal of Korean Academy of Sensory Integration
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    • v.7 no.1
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    • pp.27-36
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    • 2009
  • Introduction : Occupational therapists commonly use clinical observation to assess neuromuscular function witch is a fundamental component of sensory integration function. Clinical Observation of Motor and Postural Skills (COMPS) is a standardized assessment with seven items and used to screen if a child's problem is due to neuromuscular and sensory integration system. However, developmental standard of the test need to be validated with Korean children. Objective : This study is purposed to propose developmental standard of the COMPS for Korean children. Method : Seven to nine years old students (76 male and 70 female) participated in this study. In order to find out any difference by gender and age, the data was analyzed using t-test and ANOVA. Results : There is no significant difference by gender for all other items except Prone Extension Position (PEP). There is significant difference between children who are 7 years old and those who are 9 years old for Slow Motion(SM), Finger-Nose Touching (FNT), Asymmetrical Tonic Neck Reflex (ATNR), Supine Flexion(SF). There is also significant difference between those who are 8 years old and 9 years old for SM, FNT, ATNR. However, there is no significant difference between those who are 7 years and 8 years old. Conclusions : This study examines any difference in neuromuscular characteristics by age among school-aged children, based on the COMPS. The result of this study will provide a good evidence to establish developmental standard of COMPS for Korean children. It issuggested to continue further standardization work of the COMPS in order to establish a developmental standard for Korean children.

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