• Title/Summary/Keyword: Research design

Search Result 44,833, Processing Time 0.101 seconds

Development of Optimal Seed Production Methods Using Domestic Rye Cultivar in Central and North Area of Korea (중·북부지역에서 국내육성 호밀품종의 채종방법)

  • Han, Ouk-Kyu;Song, Ju-Hee;Ku, Ja-Hwan;Kim, Dea-Wook;Kwon, Young-Up;Lee, Yu-Young;Park, Chang-Hwan;Kweon, Soon-Jong;Ahn, Jong-Woong
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.38 no.1
    • /
    • pp.44-52
    • /
    • 2018
  • This experiment was conducted at Suwon, Korea from 2013 to 2015. The objective of this study was to establish the optimum seeding rate, and to clarify the nitrogen fertilizer level for rye seed production in central and north area of Korea. We used Korean rye cultivar 'Gogu' for this test. We employed a split-plot design with three replications. The main plots were designed by three seeding levels (3, 5 and $7kg\;10a^{-1}$), but other sub-plots were randomly seeded. The plots were treated with three different nitrogen fertilizer levels (3, 6 and $9kg\;10a^{-1}$). The percentage of productive tiller, number of grain per spike, fertility rate, 1 liter weight, and 1000-grain weight decreased as seeding rate increased from $3kg\;10a^{-1}$ to $7kg\;10a^{-1}$, whereas the number of spike per $m^2$ increased. Therefore the grain yields of rye had less of an effect by increasing seeding rate. There was an increase in number of spike per $m^2$, number of grain per spike, and fertility rate as nitrogen fertilizer level increased from $3kg\;10a^{-1}$ to $9kg\;10a^{-1}$, but grain yields significantly not affected by the interaction of seeding rate ${\times}$ nitrogen fertilizer levels. However, the best seeding rate and nitrogen fertilizer level for rye seed production were 5 kg and $5{\sim}6kg\;10a^{-1}$, respectively, considering seed and fertilizer reduction and the prevention of pollution by excess fertilization.

Effect of Silicate on Creeping Bentgrass Growth of Green at the Golf Course during Summer in Korea (규산염의 시비가 크리핑 벤트그래스의 여름철 생육에 미치는 영향)

  • Lee, Jae-Pil;Yoo, Tae-Young;Moon, Se-Jong;Ham, Suon-Kyu;Kim, Doo-Hwan
    • Asian Journal of Turfgrass Science
    • /
    • v.22 no.2
    • /
    • pp.217-223
    • /
    • 2008
  • This study was conducted to figure out the effect of silicate as growth stimulator on growth of 'Pencrosss' creeping bentgrass. Creeping bentgrass(Agrostis palustris cv. 'Pencross') at the nursery of Sinwon Country Club was used. Silicate was applied at the concentration of 0, $200{\times}$, $500{\times}$, $1.000{\times}$. Polt size was 1 by 2 meter and there were three replications with completely randomized design(CRD). Creeping bentgrass growth was evaluated with visual turf grass quality, root length and No. of tiller density(ea/$cm^2$). Results of this study are as followings; 1. Average root length with silicate was $1.5{\sim}1.9cm$ longer than control. Especially, Root length of silicate was $7{\sim}8cm$ in summer. 2. Tiller density with silicate was $l8{\sim}22ea/cm^2$, $0.4{\sim}2.l$ less than control. But there was no significant difference. 3. Visual turfgrass quality with silicate was $5.0{\sim}8.3$, $0.3{\sim}1.5$ higher than control. But there was no significant difference. In conclusion, silicate might be grown as root growth stimulator of creeping bentgrass during summer in Korea. However, this study was conducted under one year. Accordingly, in-depth experiment should be done over several years.

Factors which Influence Customers' Intention to Switch from Call-Based Driver-for-hire Services to App-Based Driver-for-hire Services Based on Online to Offline (O2O) Business Model: Focusing on Kakao Driver service (콜 대리업체 서비스에서 O2O 방식이 적용된 대리운전 사업 모델로의 소비자 전환 의도에 관한 연구: 카카오 드라이버를 중심으로)

  • Kim, Daewon;Jeong, Hye Seung
    • The Journal of Society for e-Business Studies
    • /
    • v.21 no.3
    • /
    • pp.51-78
    • /
    • 2016
  • Online-to-offline (O2O) commerce is the new trend that merges online commerce with traditional industries in various fields. The primary purpose of this paper is to find out which factors influence customers' intention to switch from call-based driver-for-hire services to O2O app-based services. This study used variables and factors based on Theory of Switching Intention, and Extended Unified Theory of Acceptance and Use of Technology in order to design research questions. We surveyed 500 users of call-based driver-for-hire services. According to the result of this study, dissatisfaction with the current call-based driver-for-hire services is estimated to be a significant factor that strengthens customers' intention to switch from the call-based driver-for-hire services to the app-based services. Loyalty to the previous call-based driver-for-hire services was not seen as a crucial motivator that causes customers to switch to the new O2O driver service. Switching cost also did not play a key role in explaining the relationship between dissatisfaction with the current call-based service and the intention to use the new app-based service. Performance expectancy, easiness in use, the level of user's knowledge or available assistance in relation to the use of app-based services, and expectancy for reasonable price was found to have meaningful impacts on customers' intention to switch from the call-based driver-for-hire services to the app-based services. Age, gender and user experience on the new service were found incapable of moderating the relationship between aforementioned factors which influence customers' choice of the app-based driver-for-hire service, and customers' intent to switch to the app-based service.

Strategies of Large Park Development and Management through Governance - Case Studies of The Presidio and Sydney Harbour National Park - (거버넌스를 통한 대형 도시공원의 조성 및 운영관리 전략 - 프레시디오 공원과 시드니 하버 국립공원 사례를 중심으로 -)

  • Sim, Joo-Young;Zoh, Kyung-Jin
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.44 no.6
    • /
    • pp.60-72
    • /
    • 2016
  • This study aims to suggest strategies of development and management for large parks by examining experimental cases of park governance models related to a shift away from public administration. The shifts towards governance as well as public-private partnership in city parks have involved the need for new public management. This study has analyzed two exemplary cases of Presidio Park and Sydney Harbour National Park in the aspects of planning process and management strategies, as the results derived the meaning and effect of park governance management and is also an essential prerequisite for the achievement of the model. There are six dimensions of research frames--namely policy, governance, partnership, finances and funds, design and maintenance-management, and evaluation-monitoring-taken as the basis for this study. Through the analysis, several key characteristics of these cases were elicited. First, the park planning process must be consistent in carrying a policy from planning to implementation, and furthermore, an independent operation body which can properly authorize an execution and uphold its responsibility from the public could serve in adaptable park services. Second, it has been suggested to build various partnerships with PAs and NGOs, private corporations, community groups, and academic institutes that allow it to expand the diversity of the park activities. Third, there has been experimental exploration to achieve a financially self-sufficient model by establishing internal revenue models and hence allow the reduction of reliance on public finances. The result of this type of park management would allow for improving park quality and make the park space a vital part of the local economy. Fourth, the strategies for a local community's participation are needed to allow the community to become a producer as well as a consumer. This study shows that the direction and significance of the park governance model regarding the fact that the plans sought by the two parks are extending the layout of public-centered discussion to the private sector and the third non-governmental sector including to the local community group. This shows both implications and limitations, such as the risk of privatization through non-governmental activities at the park or the violation of essential functions as a public good due to a profit-generating management policy for securing financial self-sufficiency. At the current point in which plans are under way for the development and management of large parks, a park governance model requires continuous study and expansion of discussion in the future.

Effect of the Characteristics of Organizational Support on Company HRD Education & Training Program (기업 HRD 교육훈련 프로그램의 조직지원 특성에 따른 효과성)

  • Ryu, Seok-Woo;Yang, Hea-Sool
    • The Journal of the Korea Contents Association
    • /
    • v.12 no.6
    • /
    • pp.497-507
    • /
    • 2012
  • This study aims to verify how the characteristics of organizational supporting unit affect the effectiveness of company-wide HRD Education & Training program. To achieve this objective, we performed an empirical analysis, with the characteristics of organizational supporting unit comprising supervisor's support, job support, and company support as independent variables, and with the level of reaction stage, learning stage, transfer stage, and result stage as dependent variables. Empirical data was collected during the period from August 16, 2011 to September 9, 2011 by sending out questionnaires to employees of 5 securities firms listed on KOSDAQ where online and offline education & training program is running year-round with headquarter in Seoul. A total of 340 questionnaires were sent out three times for the survey, and total of 164 questionnaires were sampled for the final analysis. According to the outcome of the analysis, regarding the first hypothesis that tries to reveal how the characteristics affect the level of reaction stage, it is verified that all of supervisor's support, job support and company support have positive impact on the level of reaction stage with p value less than 0.01. In regard to the second hypothesis that tries to see how the characteristics affect the level of learning stage, it is confirmed that supervisor's support, job support and company support have significant impact on the level of learning stage with p value less than 0.05 or 0.01, respectively. Concerning the third hypothesis that aims to investigate how the characteristics affect the level of transfer stage, it is appeared that all of supervisor's support, job support and company support have positive impact on the level of transfer stage. And lastly, as for the fourth hypothesis that tries to see how the characteristics affect the level of result stage, it is analyzed that supervisor's support, job support and company support have positive impact on the level of result stage with p value less than 0.01. This study reconfirm the outcomes of previous research, which is that the effectiveness of company-wide education & training program depends not only on the contents and quality of education & training program, but also more importantly on the role of organizational supporting unit, and the working environment where what is learned in classroom can be applied to real business. Companies or experts that run education & training program in real world should recognize that the performance of training is dependent more significantly on the characteristics of organizational supporting unit rather than the design or features of education & training program.

Experimental Study on Structural Behavior of Precast PSC Curved Girder Bridge (프리캐스트 PSC 곡선 거더교의 구조거동에 대한 실험적 연구)

  • Kim, Sung Jae;Kim, Sung Bae;Uhm, Ki Ha;Kim, Jang Ho Jay
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.34 no.6
    • /
    • pp.1731-1741
    • /
    • 2014
  • Recently, many overpasses, highway, and advanced transit systems have been constructed to distribute the traffic congestion, thus small size of curved bridges with small curvature such as ramp structures have been increasing. Many of early curved bridges had been constructed by using straight beams with curved slabs, but curved steel beams have replaced them due to the cost, aesthetic and the advantage in building the section form and manipulating the curvature of beams, thereby large portion of curved bridges were applied with steel box girders. However, steel box girder bridges needs comparatively high initial costs and continuous maintenance such as repainting, which is the one of the reason for increasing the cost. Moreover, I-type steel plate girder which is being studied by many researchers recently, seem to have problems in stability due to the low torsional stiffness, resulting from the section characteristics with thin plate used for web and open section forms. Therefore, in recent studies, researchers have proposed curved precast PSC girders with low cost and could secured safety which could replace the curved steel girder type bridges. Hence, this study developed a Smart Mold system to manufacture efficient curved precast PSC girders. And by using this mold system a 40 m 2-girder bridge was constructed for a static flexural test, to evaluate the safety and performance under ultimate load. At the manufacturing stage, each single girder showed problems in the stability due to the torsional moment, but after the girders were connected by cross beams and decks, the bridge successfully distributed the stress, thereby the stability was confirmed. The static loading test results show that the initial crack was observed at 1,400 kN when the design load was 450 kN, and the load at the allowable deflection by code was 1,800 kN, which shows that the safety and usability of the curved precast PSC bridge manufactured by Smart Mold system is secured.

Analysis of Flexural Behavior of Composite Beam with Steel Fiber Reinforced Ultra High Performance Concrete Deck and Inverted-T Shaped Steel with Tension Softening Behavior (인장연화거동을 고려한 강섬유 보강 초고성능 콘크리트 바닥판과 역T형 강재 합성보의 휨거동 해석)

  • Yoo, Sung-Won;Yang, In-Hwan;Jung, Sang-Hwa
    • Journal of the Korea Concrete Institute
    • /
    • v.27 no.2
    • /
    • pp.185-193
    • /
    • 2015
  • Ultra high performance concrete (UHPC) has been developed to overcome the low tensile strengths and brittleness of conventional concrete. Considering that UHPC, owing to its composition and the use of steel fibers, develops a compressive strength of 180 MPa as well as high stiffness, the top flange of the steel girder may be superfluous in the composite beam combining a slab made of UHPC and the steel girder. In such composite beam, the steel girder takes the form of an inverted-T shaped structure without top flange in which the studs needed for the composition of the steel girder with the UHPC slab are disposed in the web of the steel girder. This study investigates experimentally and analytically the flexural behavior of this new type of composite beam to propose details like stud spacing and slab thickness for further design recommendations. To that goal, eight composite beams with varying stud spacing and slab thickness were fabricated and tested. The test results indicated that stud spacing running from 100 mm to 2 to 3 times the slab thickness can be recommended. In view of the relative characteristic slip limit of Eurocode-4, the results showed that the composite beam developed ductile behavior. Moreover, except for the members with thin slab and large stud spacing, most of the specimens exhibited results different to those predicted by AASHTO LRFD and Eurocode-4 because of the high performance developed by UHPC.

The effect of practical reasoning Home Economics instruction on morality of middle school students (실천적 추론 가정과 수업이 중학생의 도덕성에 미치는 효과)

  • 채정현;유태명;박미정;이지연
    • Journal of the Korean Home Economics Association
    • /
    • v.41 no.12
    • /
    • pp.53-68
    • /
    • 2003
  • The purpose of this study was to develop lesson plans and teaching materials applying practical reasoning instruction for the 7th home economics curriculum content, and to test the effect of practical reasoning instruction on morality of middle school students. This study is a quasi-experimental research with a pretest-posttest design. Practical reasoning instruction for experimental group and traditionally lecture oriented instruction for comparison group were input, and tested the statistical differences between two groups before and after the treatment. The subjects for this study were 8th grade students of a middle school located in Kwangju city. Two classes of 76 students homogeneous in characteristics and academic record for each experimental and comparison group were assigned. Instrument used for this study was a revised moral indicator, that was developed by KEDI(2001). Spss/win for 10.0 statistics program was used for analysis of data. ANCOVA was done for testing statistical difference between pretest and posttest of experiment group and comparison group. Result of study which showed statistically significant difference between groups were:1. Virtue of "responsibility for words and deeds"(from 3.22 to 3.61 for experimental group and from 3.27 to 3.26 for comparison group) in domain of responsibility and cooperation, and virtue of "punctuality"(from 3.59 to 3.76 for experimental group and from 3.41 to 3.28 for comparison group) in domain of trustworthiness, 2. Virtue of "conversation etiquette"(from 3.47 to 3.67 for experimental group and from 3.28 to 3.31 for comparison group) in domain of caring for others, 3. Virtue of "forgiveness other′s mistakes"(from 3.32 to 3.65 for experimental group and from 3.33 to 3.25 for comparison group) in domain of kindness, concession, forgiveness, and virtue of "volunteering activity"(from 2.89 to 3.71 for experimental group and from 3.36 to 3.45 for comparison group) in domain of compassion and service, 4. Virtue of "equip the convenient facility for handicapped"(from 4.19 to 4.29 for experimental group and from 4.17 to 3.91 for comparison group) in domain of equality and human rights, virtue of "recovering selfness for own community"(from 2.34 to 2.79 for experimental group and from 2.14 to 2.29 for comparison group), virtue of "opposing way of accomplishing purpose by an means"(from 3.27 to 3.31 for experimental group and from 3.47 to 3.05 for comparison group), virtue of "opposing election of considering acquaintance"(from 3.35 to 3.56 for experimental group and from 3.12 to 3.14 for comparison group) in domain of fairness, and virtue of "eradication of military force or violence among countries"(from 3.49 to 3.57 for experimental group and from 3.38 to 3.05 for comparison group) in domain of love for humanity. The morality of experimental group was improved more than that of comparison group in all of above items. From the results of this study, following conclusion was drawn. Practical reasoning instruction in home economics is effective in raising students′ virtue and value of responsibility in words and deeds, trustworthiness in punctuality, courtesy of not interrupting conversation, forgiveness of other′s mistakes, volunteering activity, equity for handicapped, fairness opposing selfness for own community, fairness opposing way of accomplishing purpose by all means, fairness opposing election of considering acquaintance, and love for humanity opposing war.

Privilege and Immunity of Information and Data from Aviation Safety Program in Unites States (미국 항공안전데이터 프로그램의 비공개 특권과 제재 면제에 관한 연구)

  • Moon, Joon-Jo
    • The Korean Journal of Air & Space Law and Policy
    • /
    • v.23 no.2
    • /
    • pp.137-172
    • /
    • 2008
  • The earliest safety data programs, the FDR and CVR, were electronic reporting systems that generate data "automatically." The FDR program, originally instituted in 1958, had no publicly available restrictions for protections against sanctions by the FAA or an airline, although there are agreements and union contracts forbidding the use of FDR data for FAA enforcement actions. This FDR program still has the least formalized protections. With the advent of the CVR program in 1966, the precursor to the current FAR 91.25 was already in place, having been promulgated in 1964. It stated that the FAA would not use CVR data for enforcement actions. In 1982, Congress began restricting the disclosure of the CVR tape and transcripts. Congress added further clarification of the availability of discovery in civil litigation in 1994. Thus, the CVR data have more definitive protections in place than do FDR data. The ASRS was the first non-automatic reporting system; and built into its original design in 1975 was a promise of limited protection from enforcement sanctions. That promise was further codified in an FAR in 1979. As with the CVR, from its inception, the ASRS had some protections built in for the person who might have had a safety problem. However, the program did not (and to this day does not) explicitly deal with issues of use by airlines, litigants, or the public media, although it appears that airlines will either take a non-punitive stance if an ASRS report is filed, or the airline may ignore the fact that it has been filed at all. The FAA worked with several U.S. airlines in the early 1990s on developing ASAP programs, and the FAA issued an Advisory Circular about the program in 1997. From its inception, the ASAP program contained some FAA enforcement protections and company discipline protections, although some protection against litigation disclosure and public disclosure was not added until 2003, when FAA Order 8000.82 was promulgated, placing the program under the protections of FAR 193, which had been added in 2001. The FOQA program, when it was first instituted through a demonstration program in 1995, did not contain protections against sanctions. Now, however, the FAA cannot take enforcement action based on FOQA safety data, and an airline is limited to "corrective action" under the program. Union contracts can exclude FOQA from the realm of disciplinary action, although airline practice may be for airlines to require retraining if there is no contract in place forbidding it. The data is protected against disclosure for litigation and public media purposes by FAA Order 8000.81, issued in 2003, which placed FOQA under the protections of FAR 193. The figure on the next page shows when each program began, and when each statute, regulation, or order became effective for that program.

  • PDF

A Feasibility Study on the Use of Liner and Cover Materials Using Sewage Sludge (하수슬러지의 차수재 및 복토재로의 이용타당성에 관한 연구)

  • 유남재;김영길;박병수;정하익
    • Journal of the Korean Geotechnical Society
    • /
    • v.15 no.2
    • /
    • pp.43-71
    • /
    • 1999
  • This research is an experimental work of developing a construction material using municipal wastewater sludge as liner and cover materials for waste disposal landfill. Weathered granite soil and flyash, produced as a by-product in the power plant, were used as the primary additives to improve geotechnical engineering properties of sludge. For secondary additives, bentonite and cement were mixed with sludge to decrease the permeability and to increase the shear strength, respectively. Various laboratory test required to evaluate the design criteria for liner and cover materials, were carried out by changing the mixing ratio of sludge with the additives. Basic soil properties such as specific gravity, grain size distribution, liquid and plastic limits were measured to analyze their effects on permeability, compaction, compressibility and shear strength properties of mixtures. Laboratory compaction tests were conducted to find the maximum dry densities and the optimum moisture contents of mixtures, and their effectiveness of compaction in field was consequently evaluated. Permeability tests of variable heads with compacted samples, and the stress-controlled consolidation tests with measuring permeabilities of samples during consolidation process were performed to obtain permeability, and to find the compressibility as well as consolidational coefficients of mixtures, respectively. To evaluate the long term stability of sludges, creep tests were also conducted in parallel with permeability tests of variable heads. On the other hand, for the compacted sludge decomposed for a month, permeability tests were carried out to investigate the effect of decomposition of organic matters in sludges on its permeability. Direct shear tests were performed to evaluate the shear strength parameters of mixed sludge with weathered granite, flyash and bentonite. For the mixture of sludge with cement, unconfined compression tests were carried out to find their strength with varying mixing ratio and curing time. On the other hand, CBR tests for compacted specimen were also conducted to evaluate the trafficability of mixtures. Various test results with mixtures were assessed to evaluate whether their properties meet the requirements as liner and cover materials in waste disposal landfill.

  • PDF