• Title/Summary/Keyword: driving stress

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Sustainable animal agriculture in the United States and the implication in Republic of Korea

  • Inkuk Yoon;Sang-Hyon Oh;Sung Woo Kim
    • Journal of Animal Science and Technology
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    • v.66 no.2
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    • pp.279-294
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    • 2024
  • Agriculture has played a significant role in the national economy, contributing to food security, driving economic growth, and safeguarding the dietary habits of the population. Korean agriculture has been compelled to focus on intensive farming due to its limited cultivation area, excessive input costs, and the limitations of agricultural mechanization. In the Republic of Korea (R.O.K), the concept of environmentally friendly animal agriculture began to be introduced in the early 2000s. This concept ultimately aims to cultivate sustainable animal agriculture (SAA) through environmentally friendly production practices, ensuring the healthy rearing of animals to supply safe animal products. Despite the government's efforts, there are still significant challenges in implementing environmentally friendly agriculture and SAA in the R.O.K. Therefore, the objective of this review is to establish the direction that the animal agriculture sector should take in the era of climate crisis, and to develop effective strategies for SAA tailored to the current situation in the R.O.K by examining the trends in SAA in the U.S. The animal agriculture sector in the U.S. has been working towards creating a SAA system where humans, animals, and the environment can coexist through government initiatives, industry research, technological support, and individual efforts. Efforts have been made to reduce emissions like carbon, and improve factors affecting the environment such as the carbon footprint, odor, and greenhouse gases associated with animal agriculture processes for animals such as cattle and pigs. The transition of the U.S. towards SAA appears to be driven by both external goals related to addressing climate change and the primary objectives of responding to the demand for safe animal products, expanding consumption, and securing competitiveness in overseas export markets. The demand for animal welfare, organic animal products, and processed goods has been increasing in the U.S. consumer market. A major factor in the transformation of the U.S. animal agriculture sector in terms of livestock specifications is attributed to environmentally friendly practices such as high-quality feed, heat stress reduction, improvements in reproductive ability and growth period reduction, and efforts in animal genetic enhancement.

The Behavior of Stabilizing Piles installed in a Large-Scale Cut Slope (대규모 절개사면에 설치된 억지말뚝의 거동)

  • Song, Young-Suk;Hong, Won-Pyo
    • The Journal of Engineering Geology
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    • v.19 no.2
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    • pp.191-203
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    • 2009
  • The effect of stabilizing piles on cut slopes is checked and the behavior of slope soil and piles are observed throughout the year by field measurements on the large-scale cut slopes. First of all, the behavior of the slope soil was measured by inclinometers during slope modification. Landslides occurred in this area due to the soil cutting for slope modification. The horizontal deformations of slope soil are gradually increased and rapidly decreased at depth of sliding surface. As the result of measuring deformation, the depth of sliding surface below the ground surface can be known. Based on the measuring the depth of the sliding surface, some earth retention system including stabilizing piles were designed and constructed in this slope. To check the stability of the reinforced slope using stabilizing piles, an instrumentation system was installed. As the result of instrumentation, the maximum deflection of piles is measured at the pile head. It is noted that the piles deform like deflection on a cantilever beam. The maximum bending stress of piles is measured at the soil layer. The pile above the soil layer is subjected to lateral earth pressure due to driving force of the slope, while pile below soil layer is subjected to subgrade reaction against pile deflection. The deflection of piles is increased during cutting slope in front of piles for the construction of soil nailing. As a result of research, the effect and applicability of stabilizing piles in large-scale cut slopes could be confirmed sufficiently.

Experimental Studies on the Structural Safety of Pipe-Houses (파이프하우스의 구조안전에 관한 실험적 연구)

  • 김문기;남상운
    • Journal of Bio-Environment Control
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    • v.4 no.1
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    • pp.17-24
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    • 1995
  • This study was carried out to make fundamental data for structural safety test of pipe- houses. Experiment on the stress distribution of pipe- houses was conducted to find suitable structural analysis model by examination of end support conditions of pipe. Besides, the loading test and the pile driving test were done to find pull-out capacity and bearing capacity of pipe on the assumption that pipe is pile foundation. For single span pipe - house, the theoretical results assuming the end support condition of pipe is fixed under ground agreed closely with the experimental results of stress distribution. On the other hand for double span pipe -house, the end support conditions of pipe were fixed support when vertical load is applied, and hinged one when horizontal load is applied. The pull - out capacity and allowable bearing capacity of the pipe portion that was buried in the grounds that were soft soil of paddy field and medium or hard soils of dry field derived from experimental results.

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Photochemical Index Analysis on Different Shading Level of Garden Plants (정원 식물의 차광 조건별 광화학적 생리지표 해석)

  • Kang, Hong Gyu;Kim, Tae Seong;Park, So Hyun;Kim, Tae Wan;Yoo, Sung Yung
    • Korean Journal of Environmental Biology
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    • v.34 no.4
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    • pp.264-271
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    • 2016
  • The objective of this study was to determine the growth and light utilization efficiency of garden plants in shade area through chlorophyll fluorescence reaction analysis. Ten garden plants was grown for 75 days under 50% and 80% shading conditions. Under shading, $ET2_O/RC$, the fluorescence parameter related to electron-transport in photosystem II, was effectively enhanced. However, the electron transport flux until PSI acceptors per reaction center ($RE1_O/RC$) was reduced. These changes in photochemical parameters evoked a decrease in performance index (PI) and driving force (DF) of electron transport flux. In addition, some photochemical parameters such as $F_V$, $FV/F_O$, $RE1_O/RC$, $ET2_O/RC$, $PI_{TOTAL\;ABS}$, and $DF_{TOTAL\;ABS}$ were found to be important for shade tolerance. Three species (Pachysandra terminalis Siebold & Zucc, Physostegia virginiana L., and Carex maculata Bott) were found to be shade tolerant. Based on these results, shading factor index (SFI) deduced from photochemical parameters is useful for evaluating of shading stress of garden plants.

Development and Verification of a Large Scale Resonant Column Testing System (대형 공진주시험기의 개발 및 검증)

  • Kim, Nam-Ryong;Ha, Ik-Soo;Shin, Dong-Hoon;Kim, Min-Seub
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.32 no.6C
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    • pp.295-304
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    • 2012
  • In this study, a resonant column testing system which is the largest in Korea has been developed to evaluate the dynamic deformation characteristics of coarse granular geomaterials, and the performance and the applicability of the testing system have been verified. The system has been developed as a typical Stokoe type device whose boundary conditions are fixed bottom and free top with additional mass, and can adopt a large specimen with 200 mm in diameter and 400 mm in height. The driving and measurement instruments are configured as high performance and precision systems, hence the automated testing system is appropriate to drive enough stress and to measure the behavior precisely for the test in practical manner. The dynamic response of the mechanical components and the applicability of the system have been evaluated using metal specimens as well as polyurethane specimens, and its precision was verified by comparing its results with those from other equipment and/or methods. To confirm the applicability of the large system for coarse geomaterials, the resonant column test results from both large and normal scale apparatus for the same material were compared and it was found that the result can be partially affected by scale. Finally, the dynamic deformation characteristics of coarse geomaterial which is used for construction of large dam was evaluated using the large system and its practicality could be confirmed.

A Mathematical Model of Return Flow outside the Surf Zone (쇄파대(碎波帶) 밖에서 return flow의 수학적(數學的) 모형(模型))

  • Lee, Jong Sup;Park, II Heum
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.14 no.2
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    • pp.355-365
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    • 1994
  • An analytical model of return flow is presented outside the surf zone. The governing equation is derived from the Navier-Stokes equation and the continuity. Each term of the governing equation is evaluated by the ordering analysis. Then the infinitesimal terms, i.e. the turbulent normal stress, the squared vertical velocity of water particle and the streaming velocity, are neglected. The driving forces of return flow are calculated using the linear wave theory for the shallow water approximation. Especially, the space derivative of local wave heights is described considering a shoaling coefficient. The vertical distribution of eddy viscosity is discussed to the customary types which are the constant, the linear function and the exponential function. Each coefficient of the eddy viscosities which sensitively affect the precision of solutions is uniquely decided from the additional boundary condition which the velocity becomes zero at the wave trough level. Also the boundary conditions at the bottom and the continuity relation are used in the integration of the governing equation. The theoretical solutions of present model are compared with the various experimental results. The solutions show a good agreement with the experimental results in the case of constant or exponential function type eddy viscosity.

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The Effects of Information Systems Quality on the Performance of Emotional Labors : Focused on the Airline Call Centers (정보시스템 품질이 감정노동 성과에 미치는 영향: 항공사 콜센터를 중심으로)

  • Park, Wonhee;Kim, Shinkon;Kim, Changkyu
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.12
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    • pp.8800-8811
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    • 2015
  • When the crucial role of the agent in communicating with the customer is acknowledged well enough to relieve the agent's stress, it will lead to the decrease of the agent's emotional labor and the improvement of the business organization's performance simultaneously. However, the research on the relationship between information system and the emotional labor has been scarcely conducted even though the importance of the emotional labor is actively researched and discussed these days. Therefore, much effort has been put in this study to fine out how the quality of airline call center information system affects expectations-conformation and how expectations-conformation and self-efficacy affect performance of Emotional Labors. Analysis of the results to target a call center agent 436 people, When you provide them with quality information systems, it increased satisfaction and pride in their job. This mechanisms subsequently reduces the strength of the emotion labor, which ultimately improves the service performance. The implications of this study can be summarized as following: First, this research presented practical guidelines to the organization's decision-makers related to the airline call center operations in order to introduce and expand successful call center information system. Second, this research suggested the possible method to inspect and diagnose the system by way of applying the measurement model mentioned in this research into the airline information system and analyzing it. Third, the performance-measuring model developed in order to measure the performance of the airline call center information system can also be used when we carry out the performance-measuring task in the similar information system as the basis of diagnosing the situation and presenting the driving directions.

A Study on the Instrument Panel Design Trend for Automobile Interior (자동차 인테리어의 인스트루먼트 패널 디자인 경향 연구)

  • Cho, Kyung-Sil;Lee, Myung-Ki
    • Archives of design research
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    • v.18 no.4 s.62
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    • pp.129-138
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    • 2005
  • Until the early part of the 1990s, interior design has never been thought important by car makers. Repeated attempts have been made to systemize a technical structure, such as layout, driving method, and size, and the car's interior design has been developed by in simple comparison with the exterior design. In the 1990s, however, this trend began to change because consumers began spending more time in their cars, so the motive of the technology development became that of giving comfort and functional satisfaction to the customers. Observing how a person spends inside his or her car and considering the latest trends in car interiors have made a consumer-oriented sense of value i.e., intensifying the personality of the car's interior design and considering the emotional makeup of the consumer factor in the acquisition of a strategic brand identity. These days, car interiors assume a new concept every year due to the constant change in various factors, and the application of a high-tech design, with a sensing function and a navigation system, to achieve driverless running, is being raised as a key trend element technology for the future. Now, at the present when multilateral concept applications of design are attempted under the direct influences from other fields such as product design, fashion and furniture, I would like to lay stress on investigating and analysing the changes in car interior design varying with the background of the times and formative characteristics from the object point of view. On this study, I would like to compare the background of the times and flow of car interior design with priority given to crash pad and would like to attempt to present the direction of the future car interior design together with diversifying major technical factors.

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Prevalence Rate of Low_Back Pain and Its Related Factors in Physical Therapists (물리치료사의 요통 유병률과 관련요인)

  • Jung Soo-yeoun;Shin Hyung-soo;Park Jae-yong
    • The Journal of Korean Physical Therapy
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    • v.17 no.2
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    • pp.22-37
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    • 2005
  • This study was performed to investigate LBP(low-back pain) prevalence rate and its related factors inphysical therapists. A self-administered questionnaire survey was conducted to 522 physical therapists in Daegu and Gyeongsangbuk. The LBP prevalence rate for recent 6 months was $61.7\%$. According to age, the prevalence rate was highest in the group aged 24 or less for both male and female physical therapistis. For male physical therapists , it was higher in smokers and drivers, but for female ones, it was not in a significant relationship with smoking and driving. According to work experience, the prevalence rates of those who had been working for less than one year were the highest, and those who had been working at hospitals and clinics were $69.1\%$, significantly high. According to therapy techinque, the prevalence rate related ti PNF was $71.6\%$, the highest and to occupational therapy was $34.3\%$, the lowest. According to working environment for six months, in both male and female physical therapists. LBP prevalence rate was in a statistically significant relationship with work hours during the day, night and weekend duties, repetitive works, motions that bend or twist the waist, the number of patients per day, the number of time to help patients per day, the number of time to carry medical equipment per day and the length of time to work standing. The rate was also higher when physical therapists fekt nire stress from their work. According to the result of multiple logistic regression analysis, male was in a significant relationship with work experience and motions that bend or twist the waist and female was in a significant relationship with work hours during the night and weekend duties, the number of time to help patients per day, motions that bena or twist the waist, actions taken to protect the waist. As for the developmental pattem of LBP in the group of physical therapists with LBP for six moths, $15.7\%$ of them had LBP for first time, $42.3\%$ had recurred LBP, and $42.0\%$ had chronic LBP. As for the causes of LBP, $51.7\%$ said that it was because they worked in the same posture for a long time, and as for how to treat LBP, 48.8% said that they treated themselvs or got help from their co-wokers. The results presented above suggest that physical therapists are exposed to high risk of LBP caused form occupational activities. Therefire, it is necessary to improve working environment to reduce the occurrence of LBP and to develop education programs for preventing the occurrence and recurrence of LBP.

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Development of Steel Pipe Attached PHC Piles for Increasing Base Load Capacity of Bored Pre-cast Piles (매입말뚝의 선단지지력 증대를 위한 강관 부착 PHC파일 개발)

  • Paik, Kyu-Ho;Yang, Hee-Jeong
    • Journal of the Korean Geotechnical Society
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    • v.29 no.8
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    • pp.53-63
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    • 2013
  • Bored pre-cast piles using PHC piles is widely used in foundation of building structures constructed in urban areas because noise and vibration due to pile installation are low. However, since slime is formed at the base of borehole and the density of bearing stratum surrounding the base of borehole is decreased due to stress relaxation in drilling process of bored pre-cast pile method, the base load capacity of bored pre-cast piles is very low compared to the strength of bearing stratum. In this study, a new type of PHC pile, which short steel pipe with the same diameter as the PHC pile is attached to the pile tip, is developed to increase the base load capacity of bored pre-cast piles. In order to check the effect of the use of new PHC pile on the base load capacity of bored pre-cast piles, field pile load tests are performed for bored pre-cast piles using the new and existing PHC piles. Results of the pile load tests show that the new PHC pile gives higher base load capacity to bored pre-cast piles than the existing PHC pile, since the tip of new PHC pile is penetrated to undisturbed bearing stratum passing through the slime at the base of borehole and the loosened bearing stratum under the slime by pile driving using light hammer.