• Title/Summary/Keyword: Falling rate

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Drying Characteristics and Drying Model of Red Pepper (고추의 건조특성(乾燥特性)과 건조모델에 관(關)한 연구(硏究))

  • Cho, Y.J.;Koh, H.K.
    • Journal of Biosystems Engineering
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    • v.11 no.1
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    • pp.52-63
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    • 1986
  • This study was performed to find out drying characteristics and develop drying model for the design of an efficient dryer or drying system of red peper. The basic model which describes drying phenomenon of red pepper was firstly established, and drying tests were conducted at 14-different drying conditions. In this test, the effects of drying air temperature and relative humidity on the rate of drying were undertaken. Finally, a new drying model based on these experimental results was developed to describe the drying characteristics of red pepper. The results from this study may be summarized as follows. 1. Drying constant of the basic model established from Lewis' experimental model and diffusion equation was theoretically deduced as a function of moisture content and inner-temperature of red pepper. 2. From the results of drying tests, drying air temperature was found to have the greatest effect on the rate of drying. However, the effect of temperature was small for the condition of high relative humidity, and for low temperature, the effect of relative humidity was found to be large even though the range of relative humidity was low. 3. Modified Henderson equation was found to be better than Chung equation as the EMC model for the estimation of the equilibrium moisture content of red Pepper. 4. Constant-rate drying period did not exist in the red pepper drying test. And falling-rate drying period was divided into three distinct phases. Drying rate was dependent on the moisture content, the inner-temperature of red pepper and the change of physical property due to drying. 5. Drying constant increased with decrease of free moisture content, but it decreased at the end of the drying period. Also, drying constant was dependent on the drying air temperature and relative humidity. 6. The new drying model developed in this study was found to be most suitable in describing the drying characteristics of red pepper. Therefore, it may be concluded that drying time could be accurately estimated by the new drying model.

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The Political Economy of the Phenomenon on Convergence of Broadcasting and Telecommunication: Centering around the Law of the Tendential Fall in the Rate of Profit (방송통신융합 현상의 정치경제학적 고찰: '이윤율의 경향적 하락의 법칙'을 중심으로)

  • Kim, Dong-Min
    • Korean journal of communication and information
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    • v.34
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    • pp.7-33
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    • 2006
  • This paper try to explain the phenomenon on convergence of broadcasting and telecommunication by the law of the tendential fall in the rate of profit. With the progressive decline in the variable capital in relation to the constant capital in the sphere of the telecommunication, this tendency leads to a rising organic composition of the total capital, and the direct result of this is that the rate of surplus-value, with the level of exploitation of labour remaining the same or even rising, is expressed in a steadily falling general rate of profit. The reason to apply this law is to inquire into the true state of the phenomenon on convergence of broadcasting and telecommunication showed like the disorderly development.

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Analysis of safety risk factors of fishermen on the Korean tuna purse seiner (우리나라 다랑어선망어선의 어선원 안전 위험요소 분석)

  • KIM, O-Tae;JO, Hyun-Su;CHANG, Ho-Young;LEE, Yoo-Won
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.58 no.3
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    • pp.251-261
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    • 2022
  • Tuna purse seine fishery (TPF) constitute more than 60% of distant water fishery production in Korea based on a statistic of 2018, and 28 ships from four different companies were under operation at the western and central Pacific Ocean. On this research, common risk factors during TPF were investigated via enumeration of five years Korean fisherman's insurance payment statement, followed by some counterplans to diminish the accident rate. The accident rate of TPF on the Pacific Ocean peaked by 43.0% in 2014 and constantly decreased to 23.0% until 2018, presenting an average of 33.6%. Meanwhile, the accident rate on the Indian Ocean reached the highest point 55.1% in 2014 and declined to 11.6% in 2016, having an average of 24.7%. The average accident rate of the Indian Ocean scored 8.9% lower than the rate of the Pacific Ocean, but no statistic significance was observed. Depending on the process of operation, 'casting or hauling of net' was the most frequent part that people received an injury (40.4%). When the accidents were classified by their types, 'falling down' was the most recurrent cause of the injuries (28.5%). At the point of severity, the worst injuries were induced by crush hazard. Considering aforementioned accident frequency and severity, all the factors on the accident type list were divided into three different groups including high risk, moderate risk, and common risk. This study is expected to contribute to the reduction of occupational accidents during the work of fishermen and establishment of a safety management system for distance water fishing vessels.

Litter Production and Decomposition in the Pinus rigida Plantation in Mt. Kwan-ak (관악산에 식재된 리기다소나무림에서의 낙엽의 생산과 분해)

  • Kim, Jae-Geun;Chang, Nam-Kee
    • The Korean Journal of Ecology
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    • v.12 no.1
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    • pp.9-20
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    • 1989
  • Annual production and decomposition of litter were studied in piuns rigida platation in Mt. Kwan-ak. The peak time of litter production was October-November. The litterfalll at that time was 54% of annual litter production. But the peak time of litterfall of reproductive parts was Junejuly. The peak times of litter production in Alnus hirsuta plantation were June-July, and November. It is thought that difference of seasonal distribution of letterfall between two forest types were assigned to litter falling factors such as temperature and insects. Total amount of letter loss increased according to time. Particulary, the peak time of loss rate was July-August. It was shown that the protein and phosphorus were accumulated in the letter for an experimental period. The amount of crude protein increased to 150% of initial amount. The amount of potassium was increased by August and then decreased rapidly. The contents of crude fat, holocellulose, lignin, and Na were decreased slowly. The loss of holocellulose was the largiest among them. Calcium was in steady state. It was thought that this variation pattern was assigned to leaching of soluble parts by high temperature, rainfall and growth rate of microorganisms.

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A Study On Reduce Scheme Of Design Error In Turn-Key Projects (턴키공사 설계오류 저감방안에 관한 연구)

  • Kim Byeong-Soo;Kim Kyong-Ju
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • autumn
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    • pp.286-289
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    • 2003
  • In turn-key projects, escalation of cost by design errors is not allowed because a contractor prepares the design. Therefore, cost escalation by design errors results in increasing the cost of the prime contractor. The rate of profit decreases finally. In addition, design errors bring not only schedule delay but also serious quality problem by unknown errors. This study tries to dissolve problems, that of cost increase. process delay and a falling-off in quality by investigating cause of design errors and presenting a scheme for reducing design errors.

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Numerical Simulations of Dry and Wet Deposition over Simplified Terrains

  • Michioka, T.;Takimoto, H.;Ono, H.;Sato, A.
    • Asian Journal of Atmospheric Environment
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    • v.11 no.4
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    • pp.270-282
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    • 2017
  • To evaluate the deposition amount on a ground surface, mesoscale numerical models coupled with atmospheric chemistry are widely used for larger horizontal domains ranging from a few to several hundreds of kilometers; however, these models are rarely applied to high-resolution simulations. In this study, the performance of a dry and wet deposition model is investigated to estimate the amount of deposition via computational fluid dynamics (CFD) models with high grid resolution. Reynolds-averaged Navier-Stokes (RANS) simulations are implemented for a cone and a two-dimensional ridge to estimate the dry deposition rate, and a constant deposition velocity is used to obtain the dry deposition flux. The results show that the dry deposition rate of RANS generally corresponds to that observed in wind-tunnel experiments. For the wet deposition model, the transport equation of a new scalar concentration scavenged by rain droplets is developed and used instead of the scalar concentration scavenged by raindrops falling to the ground surface just below the scavenging point, which is normally used in mesoscale numerical models. A sensitivity analysis of the proposed wet deposition procedure is implemented. The result indicates the applicability of RANS for high-resolution grids considering the effect of terrains on the wet deposition.

Performance Improvement Method of IEEE 802.11 WLAN DCF (IEEE 802.11 WLAN에서의 DCF 성능개선 방안)

  • Park, doo-jin;Ko, dong-yub;Lim, seog-ku
    • Proceedings of the Korea Contents Association Conference
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    • 2007.11a
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    • pp.130-134
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    • 2007
  • DCF(Distributed Coordination Function) of IEEE 802.11 WLAN(Wireless Local Area Network) MAC Layer apply to CSMA/CA(Carrier Sense Multiple Access with Collision Avoidance) for solution of collision when the station try to access at the same time. But DCF happens falling performance as increasing a number of stations. In this paper, we suggest algorithm that improved performance in congestion. And we compare DCF, DCF+ and proposed algorithm respect to saturation throughput, delay, collision rate and drop rate using NS2(Network Simulator 2) simulation tool.

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A Study on the Sentence Final Tonal Patterns and the Meaning of English Wh-Questions (영어 의문사 의문문의 문미 억양 실현 양상과 의미 해석에 관한 연구)

  • Kim, Hwa-Young;Lee, Dong-Wha;Kim, Kee-Ho;Lee, Yong-Jae
    • Speech Sciences
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    • v.10 no.2
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    • pp.319-338
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    • 2003
  • The aim of this paper is to examine the sentence final tonal patterns of English wh-questions through phonetic experiments, based on Intonational Phonology, and to explain the meaning of the final phrase tones of English wh-questions. Pierrehumbert and Hirschberg (1990) suggested that it is pitch accents rather than boundary tones which play a crucial role in the meaning of a sentence, and that most of the general questions have H-H% tonal patterns in the sentence final. However, they could not explain why wh-questions had final falling tonal patterns (L-L%). While Bartels (1999) suggested that L phrase tone has the meaning of 'ASSERTION' and it could be applied to the explanation of the meaning of wh-questions' final tonal patterns. However, her suggestions are only theoretical explanation without any experimental support. In this paper, based on Bartels (1999), the data was classified into the following three classes: 1) echo wh-questions, 2) reference questions, and 3) common wh-questions. Using this data, a production test by three English native speakers was conducted. The results show that reference questions and common wh-questions have L phrase tones in the sentence final at a high rate, and echo wh-questions have H phrase tones in the sentence final at a high rate.

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Effects of Non-Absorbable Gases on the Absorption Process of Aqueous LiBr Solution Film in a Vertical Tube (II) (수직관내 리튬브로마이드 수용액막의 흡수과정에 대한 비흡수가스의 영향)

  • Kim, Byeong-Ju;Lee, Chan-U
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.22 no.4
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    • pp.499-509
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    • 1998
  • In the absorption process of water vapor in a liquid film, the composition of the gas phase, in which a non-absorbable gas is combined with the absorbate influences the transport characteristics remarkably. In the present study, the absorption processes of water vapor into aqueous solution of lithium bromide in the presence of non-absorbable gases were investigated analytically. The continuity, momentum, energy and diffusion equations for the solution film and gas phase were formulated in integral forms and solved numerically. It was found that the mass transfer resistance in gas phase increased with the concentration of non-absorbable gas. However the primary resistance to mass transfer was in the liquid phase. As the concentration of non-absorbable gas in the absorbate increased, the liquid-vapor interfacial temperature and concentration of absorbate in solution decreased, which resulted in the reduction of absorption rate. The reduction of mass transfer rate was found to be significant for the addition of a small amount of non-absorbable gas to the pure vapor, especially at the outlet of an absorber where non-absorbable gases accumulated. At higher non-absorbable gas concentration, the decrease of absorption flux was almost linear to the volumetric concentration of non-absorbable gas.

Clinical Experiences on the Treatment of Congenital Cutis Aplasia and Craniosynostosis (선천성 두피결손증 및 두개골 조기유합증의 치험 5례)

  • Lee, Kyung-Ho
    • Journal of Yeungnam Medical Science
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    • v.10 no.2
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    • pp.493-505
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    • 1993
  • The congenital cutis aplasia mainly occurs in head, sometimes involving the skull and dura mater. It's cause and the rate of falling ill are not known yet, it is the disease that rate of death is high by the infection, such as, the injured vascular hemorrhange of meningitis. Craniosynostosis is the disease the appears the skull as well as the facial deformity with growing, has from the developmental difficiency, visual distibance, motor disturbance, convulsion to the neurologic impairment of mental retardation, and accompanies the each characteristic deformity following the suture fused. Satisfactory results was achieved by local flap surgery and conservative treatment on the infant, diagnosed as the congenital cutis aplasia, case 1 Also successful treatment experiences of craniosynostosis(oxycephaly, brachycephaly, trigonocephaly, cloverleaf deformity) through the frontal bone advancement and the barrel stave asteotomy, were reviewed & pursues and investigates the intracranial volume of before and after of surgery, and then reports with the literature investigation.

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