• Title/Summary/Keyword: counter current distribution

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Investigation of Brassinosteroid Substances in Undmia pinnatifida (미역의 Brassinosteroid 활성물질검색)

  • 문제학;현규환박근형
    • KSBB Journal
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    • v.7 no.1
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    • pp.21-26
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    • 1992
  • In order to examine the presence of brassinosteroid substance in sea mustard(Undaria pinnatifida), leaves of sea mustard were extracted with MeOH. The extract was purified by slovent fractionation, counter current distribution, silica gel adsorption chromatography, charcoal adsorption chromatography, Bondesil chromatography, and reverse phase HPLC, successively. The activity was monitored by the rice inclination test and its prescence could be confirmed in each purification step. Although sea mustard contained a less amount of the active substance than the vegetative tissue of higher plants, brassinosteroid was clearly present endogenously in sea mustard. We acknowledge that our work is probably the first publication reporting the presence of brassinosteroid in marine algae plants.

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Numerical Modeling of Tide and Tidal Current in the Kangjin Bay, South Sea, Korea

  • Ro, Young-Jae;Jun, Woong-Sik;Jung, Kwang-Young;Eom, Hyun-Min
    • Ocean Science Journal
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    • v.42 no.3
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    • pp.153-163
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    • 2007
  • This study is based on a series of numerical modeling experiments to understand the tidal circulation in the Kangjin Bay (KB). The tidal circulation in the KB is mostly controlled by the inflow from two channels, Noryang and Daebang which introduce the open ocean water into the northern part of the KB with relatively strong tidal current, while in the southern part of the KB, shallowest region of the entire study area, weak tidal current prevails. The model prediction of the sea level agrees with observed records at skill scores exceeding 90 % in terms of the four major tidal constituents (M2, S2, K1, O1). However, the skill scores for the tidal current show relatively lower values of 87, 99, 59, 23 for the semi-major axes of the constituents, respectively. The tidal ellipse parameters in the KB are such that the semi-major axes of the ellipse for M2 range from 1.7 to 38.5 cm/s and those for S2 range from 0.5 to 14.4 cm/s. The orientations of the major-axes show parallel with the local isobath. The eccentricity values at various grid points of ellipses for M2 and S2 are very low with 0.2 and 0.06 on the average, respectively illustrating that the tidal current in the KB is strongly rectilinear. The magnitude of the tidal residual current speed in the KB is on the order of a few cm/s and its distribution pattern is very complex. One of the most prominent features is found to be the counter-clockwise eddy recirculation cell at the mouth of the Daebang Channel.

HTS Josephson Junctions with Deionized Water Treated Interface (증류수 계면처리를 이용한 고온초전도체 죠셉슨 접합 제작)

  • Moon, S.H.;Park, W.K.;Kye, J.I.;Park, J.D.;Oh, B.
    • Progress in Superconductivity
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    • v.2 no.2
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    • pp.76-80
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    • 2001
  • We have fabricated YBa$_2$Cu$_3$$O_{7-x}$ (YBCO) ramp-edge Josephson junctions by modifying ramp edges of the base electrodes without depositing any artificial barrier layer. YBa$_2$Cu$_3$O/7-x//SrTiO$_3$ (YBCO/STO) films were deposited on SrTiO$_3$(100) by on-axis KrF laser deposition. After patterning the bottom YBCO/STO layer, the ramp edge was cleaned by ion-beam and then reacted with deionized water under various conditions prior to the deposition of counter-electrode layers. The top YBCO/STO layer was deposited and patterned by photolithography and ion milling. We measured current-voltage (I-V) characteristics, magnetic field modulation of the critical current at 77 K. Some showed resistively shunted junction (RSJ)-type I-V characteristics, while others exhibited flux-flow behaviors, depending on the dipping time of the ramp edge in deionized water. Junctions fabricated using optimized conditions showed fairly uniform distribution of junction parameters such as I$_{c}$R$_{n}$ values, which were about 0.16 mV at 77 K with 1$\sigma$~ 24%. We made a dc SQUID with the same deionized water treated junctions, and it showed the sinusoidal modulation under applied magnetic field at 77 K. 77 K.

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Condition Monitoring and Fault Diagnosis System of Rotating Machinery (회전기기의 상태감시 및 결함탐지 시스템)

  • Jeong, Sung-Hak;Lee, Young-Dong
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.10a
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    • pp.819-820
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    • 2016
  • Electrical power distribution is consists of high voltage, low voltage and motor control center(MCC). Motor control centers involves turning the motor on and off, it is configured electronic over current relay to detect a motor overcurrent flows. Existing electronic over current relay detects electrical fault such as overcurrent, undercurrent, phase sequence, negative sequence current, current unbalance and earth fault. However, it is difficult to detect mechanical fault such as locked rotor, motor stator and rotor and bearing fault. In this paper, we propose a condition monitoring and fault diagnosis system for electrical and mechanical fault detection of rotating machinery. The proposed system is designed with signal input and control part, system interface part and data acquisition board for condition monitoring and fault diagnosis, it was possible to detect electrical fault and mechanical fault through measurement and control of insulation resistance, locked rotor, MC counter and bearing temperature.

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The Surface fCO2 Distribution of the Western North Pacific in Summer 2002 (2002년 여름 북서태평양 표층 해수의 이산화탄소 분포 특성)

  • Choi, Sang-Hwa;Kim, Dong-Seon;Shim, Jeong-Hee;Min, Hong-Sik
    • Ocean and Polar Research
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    • v.28 no.4
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    • pp.395-405
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    • 2006
  • We measured the fugacity of $CO_2$ $(fCO_2)$, temperature, salinity, nutrients and chlorophyll a in the surface water of the western North Pacific $(4^{\circ}30'{\sim}33^{\circ}10'N,\;144^{\circ}20'{\sim}127^{\circ}35'E)$ in September 2002. There were zonally several major currents which have characteristics of specific temperature and salinity (NECC, North Equatorial Counter Current; NEC, North Equatorial Current; Kuroshio etc.). Surface $fCO_2$ distribution was clearly distinguished into two groups, tropical and subtropical areas of which boundary was $20^{\circ}N$. In the tropical Int surface $fCO_2$ was mainly controlled by temperature, while in the subtropical area, surface $fCO_2$ was dependent on total inorganic carbon contents. Air-sea $CO_2$ flux showed a large spatial variation, with a range of $-0.69{\sim}0.79 mmole\;m^{-2}day^{-1}$. In the area of AE (Anticyclonic Eddy), SM(Southern Mixed region) and NM (Northern Mixed region), the ocean acted as a weak source of $CO_2$ $(0.6{\sim}0.79 mmole\; m^{-2}day^{-1})$. In NECC, NEC, Kuroshio and ECS (East China Sea), however, the fluxes were estimated to be $-0.3mmole\; m^{-2}day^{-1})$ for the first three regions and $-1.2mmole\; m^{-2}day^{-1})$ for ECS respectively, indicating that these areas acted as sinks of $CO_2$. The average air-sea flux in the entire study area was $0.15mmole\;m^{-2}day^{-1})$, implying that the western North Pacific was a weak source of $CO_2$ during the study period.

Relationship Between the Catches and the Water Temperature of Tuna in the Pacific Ocean - The Operating Results of M . S #27 Cheng Rong at Eastern Fishing Ground of Tropical Rigion - (태평양 다랑어 어장의 어획량과 수온과의 관계-청룡 제27호의 열대해역 동부어장에서의 조업결과-)

  • 김광홍
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.32 no.1
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    • pp.24-32
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    • 1996
  • This paper described on relation between the catches of tuna and the distribution of water temperature of eastern fishing ground of Tropical region in the Pacific Ocean. The data of catches and water temperature used in this paper were based log book which # 27 CHENG RONG(Gross tonnage : 399 ton) had been worked eastern fishing ground(Lat : 09$^{\circ}$N- 14$^{\circ}$S, Long : 115$^{\circ}$- 149$^{\circ}$W)from January to October, 1991. The obtained result are as follows : 1. On the relation between the catches and the geographical distribution, bigeye tuna was higher catches at Lat 4$^{\circ}$- 9$^{\circ}$N, Long 135$^{\circ}$- 139$^{\circ}$W area in the equatorial counter current region where surface water temperature was range of 27.5$^{\circ}C$ to 27.9$^{\circ}C$, yellowfin tuna was higher catches at Lat 4$^{\circ}$- 9$^{\circ}$S, Long 145$^{\circ}$- 149$^{\circ}$W in the south equatorial current region where surface water temperature was range of 28.$0^{\circ}C$ to 28.4$^{\circ}C$ and albacore tuna was higher catches at Lat 10$^{\circ}$- 14$^{\circ}$S, Long 120$^{\circ}$- 124$^{\circ}$W area in the south equatorial current region where surface temperature was range of 26.5$^{\circ}C$ to 26.9$^{\circ}C$ 2. On the relation between catches and distribution of vertical water temperature, bigeye tuna was higher catches at the water temperature of 1$0^{\circ}C$ to 12$^{\circ}C$ on depth layer between 300m and 360m, yellowfin tuna was higher catches at the water temperature of 15$^{\circ}C$ to 19$^{\circ}C$ on depth layer between 180m and 280m and albacore tuna was higher catches at the water temperature of 12$^{\circ}C$ to 14$^{\circ}C$ on depth layer between 280m and 310m. Above the result, it seemed that bigeye tuna distributed deeper layer than yellowfin and albacore tuna.

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Study on Police-led National Response against CBRN Terror by Strengthening the Standing Cooperation System of the Interagencies (다부처 상설 협력체계 구축을 통한 경찰주도 국가 화생방 테러대응 발전방안)

  • Cha, Jang-Hyeon;Kang, Taeho;Kim, Daesoo;Lee, Hochan
    • Korean Security Journal
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    • no.59
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    • pp.217-242
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    • 2019
  • Nowadays, Terrorism has become bloodier. Unlike the past, the recent terrorism has been indiscriminate in the purpose of mass- killing. Given this aspect, the threat of a CBRN attack is the biggest one to modern society. Notably, the possibility of terrorist attacks in Korea by international terrorist groups such as ISIL is higher than ever in consideration of its allusion; crusades and the devil's allied forces. To overcome these circumstances, various measures have been taken for counter terrorism at the state level including anti-terrorist legislation. Under the anti-terrorist act, police have to lead relevant inter agencies when it comes to the CBRN terror. At first glance, current countermeasures would work well. However, in order to respond quickly, the standing cooperations system of related departments need to be set up. In this sense, this article proposed a coagulatory body that could not only consider institutional-oriented organizational restructuring and response but also integrate and operate functions of various specialized institutions. It also stressed that the council should move toward a consultative body of information gathering, distribution and working- level consultation. With this cooperation system, counter-terrorism agencies can respond rapidly, stop wasting their effort and assets by about 30%. Also, they could design the atypical aspect of terrorism into standardized.

Studies on the Synthesis of Nonionic Surfactants (Ⅳ). Synthesis of myo-inositol Esters and their Surface Activities (비이온성 계면활성제의 합성에 관한 연구 (제4보). 미오-이노시톨 에스테르의 합성과 계면활성)

  • Joohwan Sohn;Kidae Nam
    • Journal of the Korean Chemical Society
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    • v.26 no.1
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    • pp.49-57
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    • 1982
  • Transesterification reactions were carried out with myo-inositol and five fatty acid methyl esters such as methyl laurate, methyl myristate, methyl palmitate, methyl stearate and methyl oleate in the dimethylsulfoxide solvent. Their products were separated by both thin layer chromatography and column chromatography, and myo-inositol monoesters were quantitatively separated by counter current distribution. We measured their surface tension, foaming power and emulsifying power, determined critical micelle concentrations by the color method, and evaluated their hydrophilic-lipophilic balance. The results show that myo-inositol monoesters exhibit surface activites.

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Tracing Fiscal Sustainability in Malaysia

  • LAU, Evan;LEE, Alvina Syn-Yee
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.3
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    • pp.91-98
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    • 2021
  • One of the concerns in the economic policy circle is the fiscal sustainability. This current research revisit the notion of fiscal sustainability for Malaysia using the Indicator of Fiscal Sustainability (IFS) developed by Croce and Juan-Ramón (2003) where we employ samples of time-series data from 1970 to 2017. The findings reveal that 40 out of 48 years, during which the calculated IFS algorithm is above the threshold of 1, imply Malaysia was fiscally unsustainable. Despite having been fiscally unsustainable, Malaysia's fiscal stance shows improvement as a result of fiscal consolidation and fiscal reforms during the sample period. This is shown by the improved calculated IFS algorithm on average, which the value improved from 1.465 in 1970-1993 to 1.377 in 1998-2004 and to 1.146 in the 2006-2013. From the policy front, this indicator can serve as a precautionary early warning measure in formulating future fiscal path for Malaysia. This can be executed by targeting debt ratio and shifting the allocation of expenditures away from less efficient toward more growth-enhancing ones, which eventually would regain fiscal space to counter any incoming economic shocks in the future. This can enhance the fiscal transparency and assist in formulating a fiscal policy strategy in Malaysia.

Profiling Approach for the Choice between Speculation and Postponement Strategy in Supply Chain Management (공급사슬관리의 예측전략과 지연전략 선택을 위한 프로파일링 접근법)

  • Kang, Sung-Wook;Kim, Gyu-Bae
    • Journal of Distribution Science
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    • v.12 no.4
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    • pp.47-54
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    • 2014
  • Purpose - The postponement strategy, which delays the form, place, and production of products as late as possible, has been widely considered as a competitive supply chain management scheme in an era of mass customization and modular manufacturing. An interesting business phenomenon is that not all manufacturing/logistics firms choose the postponement strategy. Given that postponement is a counter-measure to speculation, which has some advantages under certain environments, the current imprudent inclination toward the postponement strategy may cause firms to lose the potential of the speculation strategy, an alternative strategy in supply chain management. Building on the logistics and manufacturing literature, this study examines characteristics of two contrasting strategies, postponement and speculation, and major factors favoring each strategy. Research design, data, and methodology - We apply the profiling approach to two business cases, HP printer and LG mobile phone. The profiling approach is a method of choosing a particular strategy aligned with environmental factors. While various approaches have been used to check the fit between a business strategy and environmental factors, the literature on manufacturing strategy and logistics has commonly adopted the profiling approach. Major factors used in profiling variables are derived from the literature. Two samples, HP printer and LG mobile phone, are selected, because they represent major characteristics appropriate for each strategy. The profiling is based on data from semi-organized interviews with managers. Results - The profiling approach shows that the postponement strategy is a suitable one for HP printers. Most factors, such as product life cycle, large production volume, low-price, product value, and monetary density, support delaying end products until as late as possible. Despite some exceptions, such as delivery time and economy of scale, our analysis states that the overall profile of HP printer is favorable for the postponement strategy. On the other hand, LG mobile phone may adapt the speculation strategy. Although it has large production volume and low delivery frequency, most characteristics support the speculation strategy for this product. An interesting finding is that, despite common perception that advanced technology products such as mobile telephones favor the postponement strategy, profiling proposes the speculation strategy for this product. Conclusions - Our analysis shows that speculation is not the universal option for supply chain management, and that, when choosing a specific strategy, one should consider many factors simultaneously. A major implication of our work is to emphasize the role of environmental factors such as supply chain variables in choosing an inventory strategy, and the importance of fit rather than solely strategic orientation. A theoretical contribution is to demonstrate the benefit of the simultaneous consideration of business variables in choosing specific strategies. For practitioners, our work leads us to consider the existence and the potential of speculation as a counter-measure to postponement. In addition, the comprehensive framework in this research may be instantly used in examining a practical strategy.