• Title/Summary/Keyword: far-field effect

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한국산의 죽류에 관한 연구(제육보) 산죽류의 번식에 관하여

  • 정현배
    • Journal of Plant Biology
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    • v.7 no.2
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    • pp.9-13
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    • 1964
  • As to the up-lnd bamboos, I have reported, in my previous works, that Korea has two species in the genus of Pseudosasa, four in Pleioblastus, and other four in Sasa. In the present work, I dealt with Sasamorpha Purpurascens Nakai var. Borealis Nakai which proved the strongest vitality of all up-land bamboo yet found in various up-lands of Korea, and which might be most important from the utility view-point. This report is chiefly on its procreation. Sasamorpha Purpurascens Nakai var. Borealis Nakai can be found almost everywhere throughout the country, and its leaves and stems are much used in farms in various forms of manufacture. It is also welcomed as the feed for livestocks and as cover plants for aforestation, especially as the excellent means of errosion control on devastated hill sides. It is also widely accepted that it will provide, in the immediate future, abundant sources for the up-land bamboo pulp. As the first phase of my research plan on the subject, I undertook to determine the possible best way of its procreation, for which were included the experiments of inducing the growth of subterranean stems, the entire stand cutting, transplanting, reclaimed planting after burning etc. in order to observe the plant elongation, growing conditon, climatical effect etc. What has been fuond out so far given here as follows: 1) Of the various sections of the country, Mt. Odae area gives out the most excellent Sasamorpha Purpurascens Nakai var. Borealis Nakai(the leaf weight of which is 450 gr.) and Taekwanryong area comes the next class. This species can be transplanted anywhere in the South Korea. 2) The elongation of S.P. Nakai var. Borelais begins at around the middle of May and almost completely stops by the 20th of August. 3) The best studied transplanting season is supposed to be Feb. -April, for those transplanted during that period proved 100% of success. The next best transplanting season may be October. Rain fall does not have so much effect on transplanting as the growing season does. 4) In inducing the subterranean stems, the growing season can be ignored. The root expnsion is most animated during the months of April-June, the most active season for water absorption. Those stems induced during the winter proves more rapid growth. 5) The entire stand cutting shows greater growth than the reclaimed planting after burning and that, the growth is most vigorous during May-July, whereas during the hottest months of Aug-Sept. the growth shows only 5 cm. The new shoots grow slower both in the field of entire stand cutting and in the field of reclaimed planting after burning than in the otherwise fields.

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Domestic Research Trends on Grit (그릿에 관한 국내 연구동향)

  • Hong, Seung-Hee;Hyun, Yong-Chan;Park, Jung-Hwan
    • Journal of Convergence for Information Technology
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    • v.11 no.6
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    • pp.131-138
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    • 2021
  • The purpose of this study is to derive the implications of Grit research by analyzing domestic research trends on Grit, which is a non-cognitive subject that has been actively researched in Korea recently in order to grasp the achievements so far and to seek directions for research. The analysis method was analyzed according to the pre-set criteria (annual publication status, research subject, research method, research topic, etc.) which were focusing on KCI listed and KCI excellent Grit papers among domestic academic papers of 'RISS'. As a result of the study, from 2013 to 2019, a total of 203 papers were searched and published in 92 domestic journals. Beside that, the subjects of the study, 88 cases (43.35%) were college students and 180 cases (88.67%) were quantitative studies as the research method. So, the most common research method was quantitative research. As a quantitative research method, the structural relationship between Grit and other variables, mediating effect, difference verification, and moderation effect verification were shown in order, and qualitative research has been conducted since 2017 to develop the concept of Grit, the Grit scale, and the corresponding factor structure and validity. This study will contribute to the educational field by presenting the implications of research on the development of Grit in Korea.

Photocurrent study on the splitting of the valence band and growth of $CdGa_2Se_4$ single crystal thin film by hot wall epitaxy (Hot Wall epitaxy(HWE)법에 의한 $CdGa_2Se_4$ 단결정 박막의 성장과 가전자대 갈라짐에 대한 광전류 연구)

  • Park, Chang-Sun;Hong, Kwang-Joon
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.17 no.5
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    • pp.179-186
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    • 2007
  • Single crystal $CdGa_2Se_4$ layers were grown on a thoroughly etched semi-insulating GaAs(100) substrate at $420^{\circ}C$ with the hot wall epitaxy(HWE) system by evaporating the polycrystal source of $CdGa_2Se_4$ at $630^{\circ}C$. The crystalline structure of the single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction(DCXD). The carrier density and mobility of single crystal $CdGa_2Se_4$ thin films measured with Hall effect by van der Pauw method are $8.27{\times}10^{17}cm^{-3},\;345cm^2/V{\cdot}s$ at 293 K, respectively. The photocurrent and the absorption spectra of $CdGa_2Se_4/SI$(Semi-Insulated) GaAs(100) are measured ranging from 293 K to 10 K. The temperature dependence of the energy band gap of the $CdGa_2Se_4$ obtained from the absorption spectra was well described by the Varshni's relation $E_g(T)=2.6400eV-(7.721{\times}10^{-4}eV/K)T^2/(T+399K)$. Using the photocurrent spectra and the Hopfield quasicubic model, the crystal field energy(${\Delta}cr$) and the spin-orbit splitting energy(${\Delta}so$) far the valence band of the $CdGa_2Se_4$ have been estimated to be 106.5 meV and 418.9 meV at 10 K, respectively. The three photocurrent peaks observed at 10 K are ascribed to the $A_{1^-},\;B_{1^-},\;and\;C_{11}-exciton$ peaks.

Effect On the Air Permeability of Composting Bulking Agent (퇴비화 첨가제의 공기투과성에 대한 분석)

  • Kim, Byung Tae
    • Journal of the Korea Organic Resources Recycling Association
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    • v.20 no.3
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    • pp.71-82
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    • 2012
  • Common bulking agents in composting system include woody materials such as sawdust and woodchips. These bulking agents are mainly used for the purpose of the proper control of C/N ratio and moisture content in the composting. The topic for the effect on air permeability of bulking agents has far received relatively little attention in the composting field. This study investigated the effect of bulk density, moisture content, air-filled porosity, particle size and air flow rate on air permeability of several mixture ratios of sawdust and woodchip bulking agent. Increasing the moisture contents, the air-filled porosity was decreased and the particle size was increased for all kinds of bulking agent mixtures. Especially, with the increasing of mixing ratio of woodchip, these effects were sharply magnified. The air permeability respond to air-filled porosity was very similar to that for moisture content which was anticipated the linear relationship between air-filled porosity and moisture content. Above the region of moisture content 0.25 or 0.43(d.b.)(20 or 30% w.b.), the pressure drop decreased even though air-filled pore spaces were filling with water. Especially, to the particle size of 5 mm the pressure drop was decreased exponentially, so the air permeability was dramatically improved. By the water had the role of binding of the small particles, the macropores less resistances to air flow were created in the matrix. The effect of particle size on air permeability was much stronger than that of air-filled porosity or moisture content. And it is needed the preparing of initial particle size above 5 mm for efficient composting.

The Effects of Preparation for Old Age of the past on Activity of the elderly: The mediating effect of Psycho-Social resources (과거 노후준비가 노년기의 활동성에 미치는 영향 : 심리사회적 자원의 매개효과)

  • Shin, Soo-Min;Kim, Dongbae
    • Korean Journal of Social Welfare Studies
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    • v.44 no.3
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    • pp.57-83
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    • 2013
  • There has neither been enough research on how to approach the concept of active aging through an integrated view nor an examination to verify the relationship between preparation for old age and active aging in later life. Therefore, this research aims to verify that the elderly, who have prepared for their later life, affected their active aged life. In addition, by setting up self-efficacy and social support as mediator in the research model, this paper looks into the psycho-social resource mechanism of the relationship in depth. In order to verify the correlation of two variables, the Seoul welfare panel data, a mediating model structured by psycho-social resources created by Seoul welfare foundation in 2010, was used. The total sample size was a group of 1,492 elders aged over 65. When it came to our research methods, structured equation analysis was applied to verify the mediating effect and theoretical background. The results revealed that physical preparation, financial preparation, social preparation and leisure preparation directly affected their active aging level positively, thus, psycho-social resources showed a partial mediating effect between preparation for old age of the past and active aging level. The research implications are as follows. First, this research makes an effort to approach the concept of preparation for old age with an integrated perspective through making a construct by entire preparation types. Second, it will attempt to verify the relationship between preparation for old age in the past and active aging in terms of multi-dimension is meaningful. Third, this research reveals the function of psycho-social resource, self-efficacy and social support within the relationship. As far as the partial mediating effect is concerned, preparation for old age education for the middle-aged class should be modified as a decent field to enhance of the elderly.

The Influence of the Reference Electrode on Compound Muscle Action Potential Onset Latency and Amplitude (복합근육활동전위의 시작잠복기와 진폭에 대한 기준전극의 영향)

  • Lee, Sang-Moo;Choi, Heui-Chul;Son, Jong-Hee
    • Annals of Clinical Neurophysiology
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    • v.12 no.1
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    • pp.11-15
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    • 2010
  • Background: In belly-tendon (bipolar) montage, reference (R2) electrode placed on muscle's tendon has traditionally been considered to be electrically inactive. However, recent studies have revealed that R2 electrode is not simply referential, but actively contributes to compound muscle action potential (CMAP) waveform morphology. These findings suggest that CMAP onset latency and amplitude may also be influenced by the position of R2 electrode. This study was performed in order to evaluate the effect of R2 electrode position on CMAP onset latency and amplitude. Methods: We performed motor nerve conduction studies of median, ulnar, tibial and peroneal nerves on bilateral limbs of 20 normal subjects. We used traditional bipolar and monopolar montage and compared their CMAP onset latencies and amplitudes. In bipolar montage, recording (R1) electrode was placed on mid-belly of muscle with R2 electrode on the tendon of the muscle. In monopolar montage, R1 electrode was placed on the same site of bipolar montage, while R2 electrode was placed on the contralateral limb. Results: The mean CMAP onset latencies of median and peroneal nerves in bipolar montage were significantly different (p<0.05) with those in monopolar montage. And those of ulnar and tibial nerves were not significantly different (p>0.05). The mean CMAP amplitudes of all the tested nerves except ulnar nerve were significantly different (p<0.05). Conclusions: This study shows that change in R2 electrode position can affect the CMAP onset latency and amplitude, and these differences seem to be related to the generation of far field potential by CMAP.

A Study on the Vocational Ethics of Security and Secretary Service (전문경호비서의 직업윤리에 관한 연구)

  • Park, Ok-cheol
    • Journal of the Society of Disaster Information
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    • v.3 no.2
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    • pp.55-78
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    • 2007
  • Currently, the departments related to security and secretary service exist in 18 universities and 30 colleges in Korea in order to raise professional security and secretary personnel. Among the 18 four-year colleges in Korea, only two of them have the ethics course include in their curriculum. Also, among the 31 two-year colleges, only three of them have the ethics course included in their curriculum. Besides, as some private security and guardian companies were recently utilized in illegal actions of the rich and ruling class, contradicting their original purpose of existence, many people point out their downfall as a ?forced private army.? As a professional job, if security secretaries take advantage of the knowledge and top-secret technologies and use them for non-ethical purposes, the effect of the damage is far more serious than other fields of jobs. Therefore, taking this event as a turning point, the contract contents and the task area between the client and the security and secretary company must become more transparent in order to prevent illegal actions, and also for the people working in the security and secretary service area, it is necessary to establish a firm ethical consciousness in order to behave appropriately in their working environment. Therefore, this study examines the proper direction of work ethics of the people working in the security and secretary service according to the professionalization of their field, and also aims to propose an appropriate work ethic system such that they will not become an unfortunate victim of various scandals anymore. To do so, the concept of work ethics in professional jobs was examined; and after the code of ethics that reflect the ethical value system of each professional job was reviewed, the study suggested a specific solution for establishing the codes of ethics for security and secretary service.

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Back Analysis of the Earth Wall in Multi-layered Subgrade (다층지반에 근입된 흙막이 벽의 역해석에 관한 연구)

  • 이승훈;김종민;김수일;장범수
    • Journal of the Korean Geotechnical Society
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    • v.18 no.1
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    • pp.71-78
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    • 2002
  • This paper presents a back-calculation technique leer the prediction of the behavior of earth wall inserted in multi-layered soil deposit. The soil properties are back-calculated from the measured displacement at each construction stage and the behavior of earth wall far the next construction stage is predicted using back-calculated soil properties. For multi-layered soil deposit, the back-calculation would be very difficult due to the increase in the number of variables. In this study, to solve this difficulty, the back-calculation was performed successively from the lowest layer to the upper layers. An efficient elasto-plastic beam-column analysis was used for forward analysis to minimize the computation time of iterative back-calculation procedure. The coefficients of subgrade reaction and lateral earth pressure necessary for the formation of p-y curve were selected as back calculation variables, and to minimize the effect of abnormal behavior of the wall which might be caused by any unexpected action during construction, the difference between measured displacement increment and computed displacement increment at each construction stages is used as the objective function of optimization. The constrained sequential linear programming was used for the optimization technique to found values of variables minimizing the objective function. The proposed method in this study was verified using numerically generated data and measured field data.

The Prediction Model of a Working Pattern According to Working Time Reduction in Construction Sites (근로시간 단축에 따른 건설현장에서의 근로패턴 예측 Model)

  • Kim Hong-Ryul;Yu Il-Han;Kim Kyung-Rai;Shin Dong-Woo
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • autumn
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    • pp.316-322
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    • 2002
  • In case of reducing working time, it is difficult that the construction industry is analyzed far-reaching effects caused by a reduction of working time, by approaching with just the total amount of work. Because it has the properties such as the singularity, the outdoor using, a sense of the season unlike other industries. In order to analyze the effect of a reduction of working time on the construction industry, the example of a reduction of working time in domestic other industries related with it was analyzed intensively first. And an example in Japan, which is similar to our existing related laws and industrial structure among foreign construction industries was analyzed, and a relation with the domestic construction industries and an issue were drown a conclusion. This was applied to a field worker and a related main group participating in a real production. And it showed the prediction model for a working pattern and a dealing plan to prepare in a construction site by predicting a working pattern in the management side of a construction site annually.

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A Case Study on the Reduction of Noise and Vibration at the Backpass Heat Surface in the Power Plant Boiler (발전용 보일러 후부 전열면 소음진동 저감에 관한 연구)

  • Lee, Gyong-Soon;Lee, Tae-Gu;Moon, Seung-Jae;Lee, Jae-Heon
    • Plant Journal
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    • v.4 no.3
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    • pp.54-59
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    • 2008
  • The resonance of boiler is caused by exciting force in the gas path and it generates the vibration by the harmony of boiler's dimensional factor. According to trending toward the boiler of increasing capacity and a bigger size, it has a problem of the vibration at back-pass heating surfaces. We can predict such vibrations as comparison between vortex frequency and gas column's natural frequency. We can't rely on the method for the past decades because of changing parameters, such as an allowable error, gas temperature, gas velocity, Strouhal number. We can reduce the vibration to use the seasoning effect and change the operating condition in coal fired boiler but it's not essential solution. When the vibration occurred in the model boiler, we must measures the acoustic pressure and frequency of places for considering the means. So far, we confirmed the problem from field measures and theoretical analysis about the acoustic vibration of boiler. We installed anti-acoustic baffle in a existing boiler to change the acoustic natural frequency at the cavity, which results in reducing the acoustic vibration. The first, we prove that the acoustic resonance is caused by harmonizing vortex shedding frequency of tube heat surface with acoustic natural frequency of cavity in the range of 650~750 MW loads. The second, the acoustic resonance at the back-pass heating surface has the third order of acoustic natural frequency at the second economizer. We install five anti-acoustic baffles at the second economizer to reducing the resonance. We confirm considerably reducing the acoustic vibration of boiler during the commercial boiler.

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