• Title/Summary/Keyword: N loss

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Loss of HCN from the Pyrazine Molecular Ion: A Theoretical Study

  • Jung, Sun-Hwa;Yim, Min-Kyoung;Choe, Joong-Chul
    • Bulletin of the Korean Chemical Society
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    • v.32 no.7
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    • pp.2301-2305
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    • 2011
  • The potential energy surface (PES) for the loss of HCN or HNC from the pyrazine molecular ion was determined based on quantum chemical calculations using the G3//B3LYP method. Four possible dissociation pathways to form four $C_3H_3N^{+{{\bullet}}$ isomers were examined. A Rice-Ramsperger-Kassel-Marcus quasi-equilibrium theory model calculation was performed to predict the dissociation rate constant and the product branching ratio on the basis of the obtained PES. The resultant rate constant for the HCN loss agreed with the previous experimental result. The kinetic analysis predicted that the formation of $CH=CHN{\equiv}CH^{+{\bullet}}+HCN$ was predominant, which occurred by three consecutive steps, a C-C bond cleavage to form a linear intermediate, a rearrangement to form an H-bridged intermediate, and elimination of HCN.

Effect of Helminthiasis on Zinc Metabolism

  • Musalia, L.M.;Aggett, P.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.2
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    • pp.276-279
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    • 2001
  • The effect of helminthiasis on zinc metabolism was monitored using endogenous $^{65}Zn$ after intraperitoneal injection of 1 g of $^{65}Zn$ as zinc chloride. In the first experiment zinc turnover was investigated in 18 male weanling rats, which were randomly divided into 3 groups. One group was infected with 73 third stage larvae of Nippostrongylus brasiliensis per gram body weight ; the other groups were the pair-fed and ad lib-fed controls. The route of loss of zinc was investigated in the second experiment with the same design using 18 animals with a lower dose of infection (33 larvae per gram body weight). The biological half life of endogenous $^{65}Zn$ was lower (p<0.05) in the infected group as compared to the controls. In the later phase of infection (9th to 16th day) there was reduced retention of $^{65}Zn$ and increased loss (p<0.05) of $^{65}Zn$ from the body though urine and faeces. It was concluded that infection of N. brasiliensis was accompanied by increased loss of endogenous Zn through faeces and urine.

Complete Time Algorithm for Stadium Construction Scheduling Problem

  • Lee, Sang-Un
    • Journal of the Korea Society of Computer and Information
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    • v.20 no.9
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    • pp.81-86
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    • 2015
  • This paper suggests heuristic algorithm with linear time complexity to decide the normal and optimal point at minimum loss/maximum profit maximum shortest scheduling problem with additional loss cost and bonus profit cost. This algorithm computes only the earliest ending time for each node. Therefore, this algorithm can be get the critical path and project duration within O(n) time complexity and reduces the five steps of critical path method to one step. The proposed algorithm can be show the result more visually than linear programming and critical path method. For real experimental data, the proposed algorithm obtains the same solution as linear programming more quickly.

Study on the dynamic stiffness variation of boring bar by Taguchi Method (다구찌 방법을 이용한 보링바의 동강성 변동에 관한 연구)

  • Chun, Se-Ho;Ko, Tae-Jo
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.8 no.3
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    • pp.98-104
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    • 2009
  • The objective of this paper is to investigate the effect of factors on the dynamic stiffness variation of boring bar. The experiment was carried out by Taguchi Method and Orthogonal array table. The results indicate that overhang was found out to be dominant factor with 95% confident intervals and feed rate and depth of cut were insignificant. In addition, analysis of loss function shows that loss value increased sharply from 3D to 4D(D is a shank diameter). Consequently, there is critical point which changes property of dynamic stiffness.

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Loss of HCN from the Pyrimidine Molecular Ion: A Computational Study

  • Yim, Min Kyoung;Jung, Sun Hwa;Kim, Myung Soo;Choe, Joong Chul
    • Bulletin of the Korean Chemical Society
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    • v.33 no.12
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    • pp.4098-4102
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    • 2012
  • The potential energy surface (PES) for the loss of HCN from the pyrimidine molecular ion has been explored using quantum chemical calculations. Possible reaction pathways to form five $C_3H_3N^{+{\bullet}}$ isomers have been obtained with Gaussian 4 model calculations. The rate constant for the HCN loss and the product branching ratio have been calculated using the Rice-Ramsperger-Kassel-Marcus theory on the basis of the obtained PES. The resultant rate constant agrees with the previous experimental result. By a kinetic analysis, it is proposed that the formation of $CH=CHC{\equiv}NH^{+{\bullet}}$ is favored near the dissociation threshold, while the formation of $CH=CHN{\equiv}CH^{+{\bullet}}$ is favored at high energies.

Optimal Estimation within Class of James-Stein Type Decision Rules on the Known Norm

  • Baek, Hoh Yoo
    • Journal of Integrative Natural Science
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    • v.5 no.3
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    • pp.186-189
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    • 2012
  • For the mean vector of a p-variate normal distribution ($p{\geq}3$), the optimal estimation within the class of James-Stein type decision rules under the quadratic loss are given when the underlying distribution is that of a variance mixture of normals and when the norm ${\parallel}\underline{{\theta}}{\parallel}$ in known. It also demonstrated that the optimal estimation within the class of Lindley type decision rules under the same loss when the underlying distribution is the previous type and the norm ${\parallel}{\theta}-\overline{\theta}\underline{1}{\parallel}$ with $\overline{\theta}=\frac{1}{p}\sum\limits_{i=1}^{n}{\theta}_i$ and $\underline{1}=(1,{\cdots},1)^{\prime}$ is known.

Ammonium and Nitrate Uptake and Utilization Efficiency of Rice varieties as Affected by Different N-Concentrations

  • Choi Kyung-Jin;Swiader John M.
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.50 no.1
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    • pp.22-27
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    • 2005
  • To find out the optimum mixture ratio of ammonium and nitrate on rice plant, 4 rice varieties were examined during 14days after transplanting in hydroponics with the different ratio of ammonium to nitrate(100 : 0, 75: 25,50: 50, 25: 75 and 0: 100). The highest N uptake from solution and the maximum plant dry weight were $60\~70\%$ ammonium and $30\~40\%$ nitrate mixture treatment both in Japonica and Tongil type rice plants. And with the same varieties N-uptake and N use-efficiency were compared between 10.0 mM and 1.0 mM nitrogen using $70\%$ ammonium and $30\%$ nitrate for 24 days after transplanting. Rice plants absorbed more nitrogen$(131\~145\%)$ in 10.0mM than 1.0mM treatment but accumulated N in rice plants were almost the same in both treatment. Among the tested rice cultivars, dry matter production and total accumulative nitrogen in rice plants were much high in Tongil type than japonica type rice cultivars. N-recovery ratios of rice plants from uptake N were $90.8-99.0\%$ in low concentration N solution(1.0 mM), but $69.4-81.7\%$ were observed in high concentration N solution(10.0 mM). It means that suppling low concentration N steadily will be better to prevent loss of N without reducing of growth in rice plants.

Effects of Vegetative Buffers on Reducing Soil Erosion and Nutrient Loss of Highland Field in Korea (고랭지밭의 토양침식 저감을 위한 완충식생대의 효과)

  • Jin, Yong-Ik;Lee, Jeong-Tae;Lee, Gye-Jun;Hwang, Seon-Woong;Zhang, Yong-Seon;Park, Chang-Young;Seo, Myung-Chul;Ryu, Jong-Soo;Jeong, Jin-Cheol;Chung, Ill-Min
    • Korean Journal of Soil Science and Fertilizer
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    • v.42 no.4
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    • pp.231-238
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    • 2009
  • This study was carried out to investigate the effect of vegetative buffer to reduce runoff and soil and nutrient loss at highland agricultural area. The soil of experimental field was classified as Ungyo series (Fine, Humic Hapludults). An area of each field with lysimeter was $50m^2(width\;2.5m{\times}length\;20m)$ and was a gradient of 17%. Chinese cabbage (Brassica campestris L.) was cultivated by general management in each field. For establishing vegetative buffer, rye (Secalecereale L.), tall fescue (Festucaarundinacea Schreb) and orchard grass (Dactylis glomerata L.) were planted at the edge of field. Rye buffers were 1m, 2m and 4m wide. Both orchard grass and tall fescue buffers were 2m wide. Vegetative buffers were set up in September 2005 and chinese cabbage was planted in June 2006. Soil loss, runoff and nutrient loss were measured from June to August in 2006. Since the precipitation amount was heavy in July, amounts of runoff, soil erosion and nutrient loss were the highest in July during this study period. In comparison with control, vegetative buffers of rye 2m, orchard grass 2m and tall fescue 2m reduced runoff by 3%, 1% and 2%, respectively. In comparison among width of rye buffer, rye 1m, rye 2m, and rye 4m reduced by 1%, 4% and 13%, respectively. Vegetative buffers of rye 2m, orchard grass 2m and tall fescue 2m showed the reducing of soil loss by 59%, 46% and 28%, respectively. In comparison among width of rye buffer, the highest reducing effect of 88% was observed in 4m treatment. Additionally, vegetative buffer reduced N, P and K losses in runoff and eroded soil which were 10 to 54%, 7 to 24% and 11 to 21%, respectively. In different widths, wider vegetative buffer showed lower loss of N, P and K in runoff and eroded soil. As a result of this study, the vegetative buffer of rye was most effective for reducing runoff and soil loss in comparisons with other plants. In addition, wider range of buffers recommended for reducing runoff and soil loss, if possible.

Analysis of inverter switched snubber using N-channel MOS-FET

  • Suzuki, Taiju;Ikeda, Hiroaki;Mizutani, Yoko;Ishikawa, Jinichi;Yoshida, Hirofumi
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10a
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    • pp.207-210
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    • 1996
  • This paper describes the analysis of the operation of the switched snubber in order to depress the surge voltage in the MOS-FET inverter. In this paper, the N-channel MOS-FET which operates faster than the P-channel MOS-FET was used for the inverter circuit. So, the inverter and switched snubber can operate at high-frequency in the order of MHz. The cause of generating the surge voltage in the high frequency inverter has been cleared, and then how to depress the surge voltage using the switched snubber consisting of an N-channel MOS-FET has been given. Furthermore, described is the power loss within the switched snubber which is made of an N-channel MOS-FET. The inverter having the N-channel MOS-FET used as a switched snubber can drive such a low impedance load such as mega-sonic transducer for a mega-sonic studied cleaner sufficiently.

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A Capacity Planning Framework for a QoS-Guaranteed Multi-Service IP network (멀티서비스를 제공하는 IP 네트워크에서의 링크용량 산출 기법)

  • Choi, Yong-Min
    • 한국정보통신설비학회:학술대회논문집
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    • 2007.08a
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    • pp.327-330
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    • 2007
  • This article discusses a capacity planning method in QoS-guaranteed IP networks such as BcN (Broadband convergence Network). Since IP based networks have been developed to transport best-effort data traffic, the introduction of multi-service component in BcN requires fundamental modifications in capacity planning and network dimensioning. In this article, we present the key issues of the capacity planning in multi-service IP networks. To provide a foundation for network dimensioning procedure, we describe a systematic approach for classification and modeling of BcN traffic based on the QoS requirements of BcN services. We propose a capacity planning framework considering data traffic and real-time streaming traffic separately. The multi-service Erlang model, an extension of the conventional Erlang B loss model, is introduced to determine required link capacity for the call based real-time streaming traffic. The application of multi-service Erlang model can provide significant improvement in network planning due to sharing of network bandwidth among the different services.

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