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Effects of The Working Surface an W-EDM (W-EDM이 가공면에 미치는 영향)

  • Kim Sei-hwan
    • Proceedings of the KAIS Fall Conference
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    • 2004.11a
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    • pp.56-58
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    • 2004
  • 프레스금형의 부품 중에서 펀치와 다이플레이트를 제작하는 방법은 공작기계만을 사용하여 제작하는 경우와 공작기계와 와이어 컷 방전가공기를(W-EDM)를 병행 사용하는 경우가 있다. 그런데 공작기계만을 사용하여 제작 할 때는 금형수명(Die Life)이 200만-230만 스트로크였는데 와이어 컷 방전가공기를 사용한 제작에서는 70만-80만 스트로크에서 금형수명을 다하고 있다. 이것은 W-EDM후에 발생되는 가공변질층으로 예측되므로 W-EDM전과 W-EDM후의 가공면에 대한 SEM촬영을 실시하여 가공변질충의 발생여부를 확인하고 이에 대한 제거방법을 연구하고자 하였다.

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Construction and operation of 100kW Photovoltaic Generation System (10kW 태양광발전시스템 설치 및 운전 현황)

  • Park, K.H.;Kim, M.U.;Lee, E.Y.
    • Proceedings of the KIEE Conference
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    • 2003.07b
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    • pp.1371-1373
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    • 2003
  • 본 논문은 10kW 태양광 발전시스템의 설치 및 운전 상황에 대한 내용으로서 발전 뿐만아니라 학습용으로 이용할 수 있도록 10kW 단독운전 또는 7kW와 3kW 병렬운전이 가능하도록 구성되었다. 태양전지판은 20직렬 10병렬로 구성되며, 10병렬 태양전지판은 방위각 $0^{\circ}$, 경사가 $46^{\circ}{\sim}8^{\circ}$로 이루어져 있으므로 필요에 따라서 다양한 경사각으로 3kW까지 선택 운전할 수 있도록 구성되어있다.

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First record of the cyanobacterial genus Wilmottia (Coleofasciculaceae, Oscillatoriales) from the South Orkney Islands (Antarctica)

  • Radzi, Ranina;Merican, Faradina;Broady, Paul;Convey, Peter;Muangmai, Narongrit;Omar, Wan Maznah Wan;Lavoue, Sebastien
    • ALGAE
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    • v.36 no.2
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    • pp.111-121
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    • 2021
  • Two cyanobacterial morphotypes isolated from Signy Island, South Orkney Islands, maritime Antarctica were characterised using a polyphasic approach combining morphological, cytological and molecular analyses. These analyses showed that the strains grouped with members of the genus Wilmottia. This genus currently includes three species, W. murrayi, W. stricta, and W. koreana. Both morphotypes analysed in this study were placed within the clade of W. murrayi. This clade showed a well-supported separation from Antarctic and New Zealand strains, as well as strains from other regions. W. murrayi was first described from Antarctica and is now known from several Antarctic regions. Confirmation of the occurrence of W. murrayi at Signy Island significantly extends its known distribution in Antarctica. In addition, a new combination, W. arthurensis, is suggested for Phormidium arthurensis.

Effects of 3-W Movie Screen Advertising on Viewers' Perceived Pleasure, Arousal, and Advertisement Evaluation: The Mediating Role of Physical Presence

  • Park, Namkee;Seo, Gi-Seul;Son, Seo-Hui
    • (The) Korean Journal of Advertising
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    • v.29 no.7
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    • pp.7-27
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    • 2018
  • This study explored the effects of three-wall (3-W) movie screen on advertisement viewers' feelings of physical presence, perceived pleasure, and evaluation of advertisements. The findings from an experiment (N = 188) in a real movie theater demonstrate that 3-W screen enhances the feelings and perception toward the advertisements, with physical presence presenting the mediating effects. Of note is that the effects of 3-W screen were presented differently depending upon the types of the advertisements; the dynamic one and the static one. The effects were mostly applied to the dynamic advertisement, but not to the static one. Given the high costs of installing 3-W screen in movie theaters, the study's findings suggest more elaborate designs of advertisements to enhance the applicability of 3-W screen.

A NOTE ON THE MIXED VAN DER WAERDEN NUMBER

  • Sim, Kai An;Tan, Ta Sheng;Wong, Kok Bin
    • Bulletin of the Korean Mathematical Society
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    • v.58 no.6
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    • pp.1341-1354
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    • 2021
  • Let r ≥ 2, and let ki ≥ 2 for 1 ≤ i ≤ r. Mixed van der Waerden's theorem states that there exists a least positive integer w = w(k1, k2, k3, …, kr; r) such that for any n ≥ w, every r-colouring of [1, n] admits a ki-term arithmetic progression with colour i for some i ∈ [1, r]. For k ≥ 3 and r ≥ 2, the mixed van der Waerden number w(k, 2, 2, …, 2; r) is denoted by w2(k; r). B. Landman and A. Robertson [9] showed that for k < r < $\frac{3}{2}$(k - 1) and r ≥ 2k + 2, the inequality w2(k; r) ≤ r(k - 1) holds. In this note, we establish some results on w2(k; r) for 2 ≤ r ≤ k.

Synthesis of Some Coumarin Derivatives and their Antimicrobial Activity

  • Hishmat, O.H.;Miky, J.A.A.;Farrag, A.A.;Fadl-Allah, E.M.
    • Archives of Pharmacal Research
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    • v.12 no.3
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    • pp.181-185
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    • 1989
  • When 3-acetyl coumarin derivatives are treated with bromine, 3-(w-bromoacetyl) coumarin derivatives are obtained. The reaction of 3-(w-bromoacetyl)coumarin derivatives with thiourea or with amines for two hours leads to the formation of 2-Amino-4-(3-coumarinyl) thiazole or 3-(w-aminoacetyl) coumarin derivatives, respectively. While 3-(w-bromoacetyl) coumarin derivatives react with amines for 5-8 hours to yield imino derivatives of 3-(w-aminoacetyl) coumarin. The antimicrobial activity of Ia-b, IIa-c, IVc-f, IVh and V$_{c}$, f, h, k, m, and q was studied.d.

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GENERALIZED SASAKIAN SPACE FORMS ON W0-CURVATURE TENSOR

  • Tugba Mert ;Mehmet Atceken
    • Honam Mathematical Journal
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    • v.45 no.2
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    • pp.215-230
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    • 2023
  • In this article, generalized Sasakian space forms are investigated on W0 -curvature tensor. Characterizations of generalized Sasakian space forms are obtained on W0-curvature tensor. Special curvature conditions established with the help of Riemann, Ricci, concircular, projective curvature tensors are discussed on W0-curvature tensor. With the help of these curvature conditions, important characterizations of generalized Sasakian space forms are obtained. In addition, the concepts of W0-pseudosymmetry and W0 -Ricci pseudosymmetry are defined and the behavior according to these concepts for the generalized Sasakian space form is examined.

Studies on the Processing of Frozen Seasoned Mackerel Meat 1. Processing of Frozen Seasoned Mackerel Meat and Changes in Its Taste Compounds during Storage (냉동고등어 조미육의 가공에 관한 연구 1. 냉동고등어 조미육의 가공 및 저장중 정미성분의 변화)

  • Lee, Eung-Ho;Kim, Myeong-Chan;Kim, Jin-Soo;Ahn, Chang-Bum;Joo, Dong-Sik;Kim, Se-Kweon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.18 no.4
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    • pp.355-362
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    • 1989
  • For the effective utilization of mackerel as a food sauce, the processing conditions of the frozen seasoned mackerel meat and the changes in taste compounds during its frozen storage were investigated. To prepare the frozen seasoned mackerel meat, the mackerel was headed, gutted manually, washed with tap water and deboned with the meat seperator. Then it was mixed with additives such as emulsion curd(32.1%, w/w), table salt(0.5%, w/w), sugar(2.0%, w/w), sodium bicarbonate(0.4%, w/w), polyphosphate(0.2%, w/w), monosodium glutamate(0.2%, w/w), onion powder(0.3%, w/w), garlic powder(0.1%, w/w), ginger powder(0.1%, w/w), soybean protein(3.0%, w/w) and sodium erythorbate(0.1%, w/w). This seasoned fish meat was frozen with contact freezer, packed In a carton box, and then stored at $-25^{\circ}C$. The moisture and lipid contents in the products were 70.8-71.7% and 10.9-11.3%, respectively. The taste compounds of the frozen seasoned mackerel meat were free amino acids(1625.0-1692.0mg/100g), nucleotides and their related compounds(316.6-366.8 mg/100g) as well as total creatinine(270.2-311.8 mg/100g), and small amount of betaine and TMAO. In free amino acids, the predominant ones were histidine, lysine, glutamic acid and arginine. It was supposed from the results that principal taste compounds of frozen seasoned mackerel meat were free amino acids, and that total creatinine, TMAO, TMA and betaine as well as nucleotides and their related compounds also played an assistant role.

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Effects of Far-infrared Irradiance at Night on Quality of Sunlight Dried Red Pepper (Capsicum annuum L.) in Plastic Houses (비닐하우스 이용 고추 건조 시 야간 원적외선등 조사량이 품질에 미치는 영향)

  • Lee, Guang-Jae;Kim, Si-Dong;Yoon, Jung-Beom;Lee, Ki-Yeol;Choi, Kyu-Hong
    • Horticultural Science & Technology
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    • v.32 no.6
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    • pp.819-826
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    • 2014
  • This study was carried out to investigate the effects of night-time far-infrared irradiance quality of red pepper dried in greenhouses. This study involved 4 treatments: sunlight alone (control), or sunlight plus nightly far-infrared irradiation at $250W{\cdot}6.6m^{-2}$ ($250W{\cdot}6.6m^{-2}$), far-infrared irradiation at $250W{\cdot}3.3m^{-2}$ ($250W{\cdot}3.3m^{-2}$), or far-infrared irradiation $500W{\cdot}3.3m^{-2}$ ($500W{\cdot}3.3m^{-2}$). The drying periods were 12 days in $500W{\cdot}3.3m^{-2}$ and $250W{\cdot}3.3m^{-2}$, and 14 days in $250W{\cdot}6.6m^{-2}$, and 15 days in the control. The daytime temperature was same among the treatments. The lowest temperature was at $23.8^{\circ}C$ in control, and $29.5-37.2^{\circ}C$ in far-infrared irradiation treatments. The marketable yield was 7-14% higher in far-infrared irradiation treatments compared to the control. The rate of marketability was higher in far-infrared irradiation treatments (93.6-96.3%) than in the control (87.0-87.5%). The American Spice Trade Association (ASTA) value was greatest in the $250W{\cdot}3.3m^{-2}$ treatment, followed by $250W{\cdot}6.6m^{-2}$, then $500W{\cdot}3.3m^{-2}$, and finally the control. Capsaicinoid content showed no regular trend among the treatments. Our results provide an optimized method for reducing drying time of red pepper under sunlight, and improving the quality of dried red pepper.

Distributional Characteristics of Fault Segments in Cretaceous and Tertiary Rocks from Southeastern Gyeongsang Basin (경상분지 남동부 일대의 백악기 및 제3기 암류에서 발달하는 단층분절의 분포특성)

  • Park, Deok-Won
    • The Journal of the Petrological Society of Korea
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    • v.27 no.3
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    • pp.109-120
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    • 2018
  • The distributional characteristics of fault segments in Cretaceous and Tertiary rocks from southeastern Gyeongsang Basin were derived. The 267 sets of fault segments showing linear type were extracted from the curved fault lines delineated on the regional geological map. First, the directional angle(${\theta}$)-length(L) chart for the whole fault segments was made. From the related chart, the general d istribution pattern of fault segments was derived. The distribution curve in the chart was divided into four sections according to its overall shape. NNE, NNW and WNW directions, corresponding to the peaks of the above sections, indicate those of the Yangsan, Ulsan and Gaeum fault systems. The fault segment population show near symmetrical distribution with respect to $N19^{\circ}E$ direction corresponding to the maximum peak. Second, the directional angle-frequency(N), mean length(Lm), total length(Lt) and density(${\rho}$) chart was made. From the related chart, whole domain of the above chart was divided into 19 domains in terms of the phases of the distribution curve. The directions corresponding to the peaks of the above domains suggest the directions of representative stresses acted on rock body. Third, the length-cumulative frequency graphs for the 18 sub-populations were made. From the related chart, the value of exponent(${\lambda}$) increase in the clockwise direction($N10{\sim}20^{\circ}E{\rightarrow}N50{\sim}60^{\circ}E$) and counterclockwise direction ($N10{\sim}20^{\circ}W{\rightarrow}N50{\sim}60^{\circ}W$). On the other hand, the width of distribution of lengths and mean length decrease. The chart for the above sub-populations having mutually different evolution characteristics, reveals a cross section of evolutionary process. Fourth, the general distribution chart for the 18 graphs was made. From the related chart, the above graphs were classified into five groups(A~E) according to the distribution area. The lengths of fault segments increase in order of group E ($N80{\sim}90^{\circ}E{\cdot}N70{\sim}80^{\circ}E{\cdot}N80{\sim}90^{\circ}W{\cdot}N50{\sim}60^{\circ}W{\cdot}N30{\sim}40^{\circ}W{\cdot}N40{\sim}50^{\circ}W$) < D ($N70{\sim}80^{\circ}W{\cdot}N60{\sim}70^{\circ}W{\cdot}N60{\sim}70^{\circ}E{\cdot}N50{\sim}60^{\circ}E{\cdot}N40{\sim}50^{\circ}E{\cdot}N0{\sim}10^{\circ}W$) < C ($N20{\sim}30^{\circ}W{\cdot}N10{\sim}20^{\circ}W$) < B ($N0{\sim}10^{\circ}E{\cdot}N30{\sim}40^{\circ}E$) < A ($N20{\sim}30^{\circ}E{\cdot}N10{\sim}20^{\circ}E$). Especially the forms of graph gradually transition from a uniform distribution to an exponential one. Lastly, the values of the six parameters for fault-segment length were divided into five groups. Among the six parameters, mean length and length of the longest fault segment decrease in the order of group III ($N10^{\circ}W{\sim}N20^{\circ}E$) > IV ($N20{\sim}60^{\circ}E$) > II ($N10{\sim}60^{\circ}W$) > I ($N60{\sim}90^{\circ}W$) > V ($N60{\sim}90^{\circ}E$). Frequency, longest length, total length, mean length and density of fault segments, belonging to group V, show the lowest values. The above order of arrangement among five groups suggests the interrelationship with the relative formation ages of fault segments.