• Title/Summary/Keyword: 'Valley' Unit

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Microstructural Analysis of SBR Blends Using Infrared Spectroscopy (적외선 분광법을 이용한 SBR 혼합물의 미세구조 분석)

  • Kim, Yeowool;Choi, Sung-Seen
    • Elastomers and Composites
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    • v.49 no.2
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    • pp.103-109
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    • 2014
  • Blends of emulsion SBR (E-SBR) and solution SBR (S-SBR) were prepared, and their microstructures (styrene, 1,2-unit, cis-1,4-unit, and trans-1,4-unit contents) were analyzed by Fourier transform infrared spectroscopy (FTIR) with transmittance mode. Method to measure absorbance by valley-to-valley baseline (TV) is objectively reasonable, but has a demerit which peak intensity of the cis-1,4-unit cannot be correctly measured. In order to obtain information for the four microstructures including cis-1,4-unit, measurement methods without correction (TM) and correction to 99% transmittance (TB) were compared to the TV method. Results obtained by the TB method were closer to those obtained by the TV one than those obtained by the TM. The microstructures were determined from the absorbances obtained by the TM and TB methods according to the ISO/FDIS 21561:2005(E). Variations of the styrene, 1,2-unit, and trans-1,4-unit contents with the blend ratio of E-SBR/S-SBR showed relatively good linearities, and there was no big difference between results obtained by the TM and TB methods. Variations of the cis-1,4-unit content with the blend ratio absolutely did not show linearities irrespective of the TM and TB methods.

The Geographical Language and Location Characteristics of Rural Settlements focused on Miwon Myeon in the Integrated Cheongju City (농촌자연마을의 지명어와 입지특성에 관한 연구 -통합청주시 미원면을 중심으로-)

  • Kim, Tai-Young
    • Journal of the Korean Institute of Rural Architecture
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    • v.17 no.4
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    • pp.25-32
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    • 2015
  • This paper is to research the geographical language and location characteristics of 126 rural settlements focused on Miwon Myeon in the Integrated Cheongju City. The main results are as follows : Firstly, the geographical languages of 126 settlements are classified and categorized in the order of nature (91units, 72.22%), manmade and location related(35 Units, 27.78%). The geographical languages of nature, quite much in comparison with the others, are also classified into 39 'mountain', 46 'valley', and 6 'stream' units in location characteristics. Secondly, the geographical languages of nature have 46 'valley' units, much in comparison with the others. The open circular valleys are extended from Miwon Ri of town center to Gubang Ri along route 19. The closed valleys are placed in the west and north band of town center with a background of mountain range. The 46 'valley' units are distributed widely throughout these places. Thirdly, The geographical languages of 39 'valley' units except original 7 'valley' units are categorized with the secondary 'mountain'(rock and topography related), 'stream', 'manmade', and 'location related'. And so in considering the location characteristics of rural settlements, we will have to grasp the another meaning of the geographical language.

The advent of Large Jar coffin Tombs in Yeongsangang River Valley (영산강류역(榮山江流域) 옹관고분(甕棺古墳) 발생(發生) 배경(背景))

  • Kim, Nak-Jung
    • Korean Journal of Heritage: History & Science
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    • v.37
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    • pp.37-63
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    • 2004
  • Large Jar had been manufactured and used broadly in Mahan area from late second century. At first, it was used for various purposes, for example storing utensils at household and religious service at tombs. But it's usage was shifted with the political expansion of Baekje. In late third century, large jar coffin appeared in tombs as an important burial unit at Yeongsangang river valley. It has specific traits such as saw blade-shaped design etc. That style is distinguished from Baekje's. Unification of form and style of large jar coffin signify the socio-political distinction between Yeongsangang river valley and Baekje. Large jar coffin was used emblemic style for this purposes by the political elites of the Yeongsangang river valley. This process was caused by political reason, that is, need for integration of the Yeongsangang river valley communities against the territorial expansion of Baekje state.

A Study on Processing and Performance of a 600dpi Master F-theta Lens (600dpi 마스터 에프세타 렌즈 가공 및 성능에 관한 연구)

  • Park, Yong-Woo;Moon, Seong-Min;Lyu, Sung-Ki
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.19 no.5
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    • pp.1-7
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    • 2020
  • This study examines the processing and performance of an f-theta lens, one of the main components used in laser printer and laser scanning systems. To design an f-theta lens, the optical path of the components of the laser scanning unit f-theta lens, cylinder lens, and collimator lens must be identified. The goal after machining the master f-theta lens is to understand the optical properties, root mean square, and peak to valley.

Development of LED sensor lights circuit by passive power factor correction circuit (수동 역률 보상회로를 이용한 LED 센서등 회로의 개발)

  • Park, Chong-Yeun;Yoo, Jin-Wan;Lee, Hak-Beom
    • Journal of Industrial Technology
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    • v.32 no.A
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    • pp.109-114
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    • 2012
  • In this paper, We studied LED(Light Emitted Diode) sensor lights system using PIR(Pyroelectric Infrared Ray) sensor, CdS and MCU(Micro Controller Unit). And applied the valley fill circuit to improve the power factor. We designed the amplifier for each sensor and the LED driver for constant current which is the buck converter. Also, we proposed the algorithm of LED control by each sensors using MCU. Experimental results showed that power factor is 92% with valley fill circuit.

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A Study on the Wall and Reservoir at the Valley Part of Stone Fortress - Focused on the Fortress of $Geoyeol-seong$ and $Seongsan-seong$ - (석축 산성의 계곡부 체성과 못(池)에 관한 연구 - 거창 거열성과 함안 성산산성을 중심으로 -)

  • Kwon, Soon-Kang;Lee, Ho-Yeol;Park, Un-Jung
    • Journal of architectural history
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    • v.20 no.3
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    • pp.7-22
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    • 2011
  • With the accumulations of outcomes from archaeological excavations of mountain fortress of three kingdoms period, there have been studies about time-periodic territory range of mountain fortress, difference in the way(method) of construction, defence system and so on from various points of view. This is an empirical study on the construction method of the valley part of stone fortress. First of all, it is required to secure large quantity of fresh water for those who lived at mountain fortress. Especially when builders of fortress construct a fortification at the valley part of stone fortress, in advance they must sufficiently consider several options including the establishment of sustainable water resources. First, when it comes to build a fortification on a ridge[or a slope] of a mountain, you have only to consider a vertical stress. However, when it comes to build a fortification at the valley part of a mountain, You must have more sufficient preparations for the constructing process. Because there are not only a vertical stress but also a horizontal pressure simultaneously. Second, a fortification of mountain fortress built by using unit building stone is a structure of masonry construction like brick construction, and the valley part of it is where the construction of the fortification begins. Third, when it comes to build a fortification at the valley part of a mountain, it seems that they use a temporary method such as coffer dam in oder to prevent the collapse of the fortification due to heavy rain. Furthermore, in response to a horizontal pressure a fortification is built by the way of its plane make an arch, or by piling up the soil with the plate method(類似版築) and earthen wall harder method(敷葉) they increase cross-sectional area of the fortification and its cutoff capacity. In front direction they put the reservoir facility for the fear that the hydraulic pressure and earth pressure are directly transmitted to the fortification. The process of constructing the fortification at the valley part of a mountain is done in the same oder as follows; leveling of ground(整地) ${\Rightarrow}$ construction of coffer dam ${\Rightarrow}$ construction of the fortification between the both banks of the valley ${\Rightarrow}$ construction of the fortification at bottom part of spill way(餘水路) between the both banks of the valley ${\Rightarrow}$ construction of spill way(餘水路) & reservoir facility ${\Rightarrow}$ construction of the fortification at upper part of spill way between the both banks of the valley. Coffer dam facility seems to be not only the protection device on occasion of flood but also an important criterion to measure the proper height of spill way or tailrace(放水路). This study has a meaningful significance in that it empirically examines the method of reduction of the horizontal pressure which the fortification at the valley part of a mountain takes, the date the construction was done, and wether the changes in climate such as heavy rainfall influence the process of construction.

Effect of Injection Temperature Condition on Root Mean Square and Peak-to-Valley of F-theta Lens (사출온도조건이 에프세타 렌즈의 표면조도와 표면형상에 미치는 영향에 관한 연구)

  • Park, Yong-Woo;Moon, Seong-Min;Lyu, Sung-Ki
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.20 no.6
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    • pp.114-120
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    • 2021
  • This study is focused on the root mean square and peak-to-valley based on the injection conditions of the f-theta lens, one of the main components of laser printers and laser scanning systems. The f-theta lens of an aspherical plastic lens requires ultra-preaction. Injection molding is typically used for the mass production of aspherical plastic lenses. In the injection-molding method, the resin in the lens shape is filled with the resin after melting the plastic pellets at a constant temperature and then cooled. It is necessary to maintain a uniform injection molding system to produce high-quality lenses. These injection-molding systems are influenced by different factors, such as pressure, speed, temperature, mold, and cooling. It is possible to obtain a lens that exhibits the optical characteristics required to achieve harmony. We investigated the root mean square and peak-to-valley caused by variations in temperature, a critical parameter in the melting and cooling of plastic resins generated inside and outside the injection mold.

Plant Community Structure Snalysis in Chohangyoung Valley of Soraksan National Park (설악산 국립공원 저항령계곡 식물군집구조)

  • 이경재;조현서;한봉호
    • Korean Journal of Environment and Ecology
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    • v.10 no.2
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    • pp.251-269
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    • 1997
  • To investigate the plant community structure of Chohangyoung valley in Soraksan National Park, thirty nine plots(each size was 100m$^{2}$) were set up and surveyed and to analyze the plant community characteristics of valley area and slope area, twenty five plots in five sites were set up and surveyed. According to DCA ordination techniques, the communities were six divided into community types, which were Pinus densiflora community, P. densiflora-Populus maximowiczii community, Po. maximowiczii-P. densiflora community, Po. maszimowiczii community, Fraxinus rhyuchophylla community, Quercus serrata community. Q. serrata community was only distrivuted at slope area and the others were distributied at valley area. The successional trend of six communities was not clearly inferred. Shannon's diversity was 0.9458~1.1769(unit area:500m$^{2}$), and soil acidity was pH 4.65~6.09 in surveyed areas. According to the belt-transect analysis, the dominant species of valley area were P. densiflora, Po. maximowiczii, but the dominant species of slope area was Q. serrata.

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MODFLOW-Farm Process Modeling for Determining Effects of Agricultural Activities on Groundwater Levels and Groundwater Recharge

  • Bushira, Kedir Mohammed;Hernandez, Jorge Ramirez
    • Journal of Soil and Groundwater Environment
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    • v.24 no.5
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    • pp.17-30
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    • 2019
  • Intensive agricultural development in Mexicali valley, Baja-California, Mexico, has induced tremendous strain on the limited water resources. Agricultural water consumption in the valley mainly relies on diversions of the Colorado River, but their water supply is far less than the demand. Hence, the use of groundwater for irrigation purposes has gained considerable attention. To account for these changes, it is important to evaluate surface water and groundwater conditions based on historical water use. This study identified the effects of agricultural activities on groundwater levels and groundwater recharge in the Mexicali valley (in irrigation unit 16) by a comprehensive MODFLOW Farm process (MF-FMP) numerical modeling. The MF-FMP modeling results showed that the water table in the study area is drawn downed, more in eastern areas. The inflow-outflow analysis demonstrated that recharge to the aquifer occurs in response to agricultural supplies. In general, the model provides MF-FMP simulations of natural and anthropogenic components of the hydrologic cycle, the distribution and dynamics of supply and demand in the study area.

Application of In Situ Measurement for Site Remediation and Final Status Survey of Decommissioning KRR Site

  • Hong, Sang Bum;Nam, Jong Soo;Choi, Yong Suk;Seo, Bum Kyoung;Moon, Jei Kwon
    • Journal of Radiation Protection and Research
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    • v.41 no.2
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    • pp.173-178
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    • 2016
  • Background: In situ gamma spectrometry has been used to measure environmental radiation, assumptions are usually made about the depth distribution of the radionuclides of interest in the soil. The main limitation of in situ gamma spectrometry lies in determining the depth distribution of radionuclides. The objective of this study is to develop a method for subsurface characterization by in situ measurement. Materials and Methods: The peak to valley method based on the ratio of counting rate between the photoelectric peak and Compton region was applied to identify the depth distribution. The peak to valley method could be applied to establish the relation between the spectrally derived coefficients (Q) with relaxation mass per unit area (${\beta}$) for various depth distribution in soil. The in situ measurement results were verified by MCNP simulation and calculated correlation equation. In order to compare the depth distributions and contamination levels in decommissioning KRR site, in situ measurement and sampling results were compared. Results and Discussion: The in situ measurement results and MCNP simulation results show a good correlation for laboratory measurement. The simulation relationship between Q and source burial for the source layers have exponential relationship for a variety depth distributions. We applied the peak to valley method to contaminated decommissioning KRR site to determine a depth distribution and initial activity without sampling. The observed results has a good correlation, relative error between in situ measurement with sampling result is around 7% for depth distribution and 4% for initial activity. Conclusion: In this study, the vertical activity distribution and initial activity of $^{137}Cs$ could be identifying directly through in situ measurement. Therefore, the peak to valley method demonstrated good potential for assessment of the residual radioactivity for site remediation in decommissioning and contaminated site.