• Title/Summary/Keyword: S/R

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A Study On the Optimization Model for the Design of Automated Warehouses (자동창고 설계를 위한 최적화 모형에 관한 연구)

  • 김성태;김재연
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.16 no.27
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    • pp.73-82
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    • 1993
  • In this paper, We determine the expected travel time for several forks Storage/Retrieval machine which is allowed multiple stops in aisle. When throughput is increased, We propose adding to fork number of each S/R machine rather than adding to number of S/R machine, We also describe such a model which determines the optimal number of each several forks S/R machine subject to constraints on the hourly throughput and warehouse dimensions. Numerical example is presented to compare warehouse shapes against each single fork, twin forks, triple forks S/R machine for various throughput values.

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Li 단층의 전자적, 구조적 성질

  • 이재일;조이현;홍순철
    • Journal of the Korean Magnetics Society
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    • v.3 no.3
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    • pp.169-172
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    • 1993
  • 총에너지 FLAPW(Full-Potential Linearized Augmented Plane Wave) 띠 방법을 이용하여 Li 단층의 구조적, 전자적 성질을 연구하였다. 삼각형 격자와 사각형 격자 구조에 대해 Wigner-Seitz의 반경 $r_{s}$를 변화시키면서 총에너지를 계산한 결과 삼각형구조가 안정하였으며, $r_{s}$가 3.7 a.u. 일때 평형이 되었다. 삼각형구조의 자성을 연구하기 위해, 스핀분극을 계산한 결과 $r_{s}$가 4.2 a.u. 일때 금속 강자성 전이가 일어나며 $r_{s}$가 5.3 a.u. 에서 완전 스핀분극이 되었다.

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Complete Assignment of $^{1}H$ and $^{13}C$-NMR Signals for (20S) and (20R)-Protopanaxadiol by 2D-NMR Techniques (2D-NMR 기법을 이용한 (20S)와 (20R)-Protopanaxadiol의 $^{1}H$- 및 $^{13}C$-NMR 완전 동정)

  • 백남인;김동선
    • Journal of Ginseng Research
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    • v.19 no.1
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    • pp.45-50
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    • 1995
  • (20S)- and (20R)-protopanaxadiol were prepared from crude ginseng saponin by chemical treatment. The $^{1}H$- and $^{13}C$-NMR signals of these compounds were fully assigned by various NMR techniques such as DEPT, 1H-1H COSY, HMQC, HMBC and NOESY.

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GORENSTEIN PROJECTIVE DIMENSIONS OF COMPLEXES UNDER BASE CHANGE WITH RESPECT TO A SEMIDUALIZING MODULE

  • Zhang, Chunxia
    • Bulletin of the Korean Mathematical Society
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    • v.58 no.2
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    • pp.497-505
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    • 2021
  • Let R → S be a ring homomorphism. The relations of Gorenstein projective dimension with respect to a semidualizing module of homologically bounded complexes between U ⊗LR X and X are considered, where X is an R-complex and U is an S-complex. Some sufficient conditions are given under which the equality ${\mathcal{GP}}_{\tilde{C}}-pd_S(S{\otimes}{L \atop R}X)={\mathcal{GP}}_C-pd_R(X)$ holds. As an application it is shown that the Auslander-Buchsbaum formula holds for GC-projective dimension.

Weak u-S-flat Modules and Dimensions

  • Refat Abdelmawla Khaled Assaad;Xiaolei Zhang
    • Kyungpook Mathematical Journal
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    • v.63 no.3
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    • pp.333-344
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    • 2023
  • In this paper, we generalize the notions uniformly S-flat, briefly u-S-flat, modules and dimensions. We introduce and study the notions of weak u-S-flat modules. An R-module M is said to be weak u-S-flat if TorR1 (R/I, M) is u-S-torsion for any ideal I of R. This new class of modules will be used to characterize u-S-von Neumann regular rings. Hence, we introduce the weak u-S-flat dimensions of modules and rings. The relations between the introduced dimensions and other (classical) homological dimensions are discussed.

Synthesis and Biological Properties of l$\beta$-Methylcarbapenems with 5'- Ethoxycarbonylmethoxy(hydroxy )iminopyrrolidinylthio Group at C-2 Position (C-2 위치에 5'-Ethoxycarbonylmethoxy(hydroxy)iminopyrrolidinylthio Group을 가진 1$\beta$-Methylcarbapenems의 합성과 생물학적 성질)

  • 오창현;안수현;백대진;홍준희;고옥현
    • YAKHAK HOEJI
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    • v.47 no.6
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    • pp.450-455
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    • 2003
  • Synthesis of (lR,5S,6S)-6-[(lR)-1-hydroxyethyl] -2-[(3S,5S)-5-(2-ethoxycarbonyl-1-moxy(hydroxy)iminoethyl)pyrrolidine-3-ylthio]-1-methylcarbapen-2-em-3-carboxylic acids (10a,l0b) were described. Methyl(2S,4S)-4-tritylthio-1-(allyloxycarbonyl)pyrrolidine-2-carboxyla late (I) was prepared from trans-4-hydroxy-L-proline with (2S,4R)-abs olute configuration as starting material. (2S,4S)-1-allyloxycarbonyl-2-(2-ethoxycarbonyl-hydroxy(methoxy )iminoethyl)-4-mercapto- pyrrolidines (6,7) were obtained from the tritylthio compound (I). (lR,5S,6S)-6-[(lR)-1-hydroxyethyl]-2-[(3S,5S)-5-(2-ethoxycarbonyl-1-methoxy(hydroxy)imino-ethyl)pyrrolidine-3-ylthio]-1-methylcarbapem-2-em-3-carboxylic acids (10a,10b) were obtained by the coupling reaction with carbapenem diphenylphosphates (8) and pyrrolidine-thiol moiety (6,7). Their in vitro antibacterial activities against both Gram-positive and Gram-negative were tested. Compounds ( 10a,10b) showed potent antibacterial activity except pseudomonas aerusinosa.

A Study on Family Caregivers' Burden of the Elderly with Dementia (가정내 치매노인간호자부담에 관한 조사연구)

  • Moon Hae Ree
    • Journal of Korean Public Health Nursing
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    • v.6 no.2
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    • pp.108-132
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    • 1992
  • The purpose of this study· is to identify sources of the caregiving burden, thereby suggesting social welfare alternetives for supporting family caregivers of the elderly with dementia. 23 family caregivers who participated in self-help group of family caregivers of dementia elderly at a welfare facility for the elderly in Seoul were seleted as the study sample. Zarit caregiving burden scale and Zarit functional impairment measurement for the elderly were adapted for this study and a number of additional variables were included in this study. Correlational analysis was utilized. The results of the study were summarized as follows : 1) The impairment of activities of daily living of the elderly was significantly related to the negative elderly. caregiver-family relationship(PADL:r=.6032 IADL : r=.5930 p<.05). 2) The impact on caregiver's health was very significantly related to the impact on the caregiver's task(r=.6233 p<.001). 3) The Impact on caregiver's health was very significantly related to the impact on the caregiver's social activity restriction(r=.6851 p<.001). 4) The impact on the caregiver's social activity was very significantly related to the impact on the caregiver's task(r=.6969 p<.001). 5) Caregiver's income was significantly related to the impact on the caregiver's task(r=.5252 p<.05). 6) Compensation(interpersonal relationship between the elderly and the caregivers, social praise and appreciation of the elderly) was important variables which affect to the feeling of the caregiving burden.

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A New Record of Prionospio depauperata (Annelida: Polychaeta: Spionidae) with DNA Barcoding Data of Four Prionospio Species in South Korea

  • Lee, Geon Hyeok;Yoon, Seong Myeong;Min, Gi-Sik
    • Animal Systematics, Evolution and Diversity
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    • v.36 no.4
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    • pp.382-386
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    • 2020
  • In this study, Prionospio depauperata Imajima, 1990 is newly reported in Korean fauna. Prionospio depauperata can be distinguished from other relatives by the four pairs of branchiae which are pinnate on chaetigers 2 and 5, and apinnate on chaetigers 3 and 4; caruncle extending to the end of chaetiger 2; and moderate dorsal crest present on chaetigers 7-13. The morphological diagnosis of P. depauperata are provided with the photographs of four Prionospio species. The mitochondrial cytochrome c oxidase subunit 1 (CO1), 16S ribosomal DNA (16S rDNA), and the nuclear 18S ribosomal DNA (18S rDNA) sequences of four Prionospio species from Korean waters, P. depauperata Imajima, 1990, P. japonica Okuda, 1935, P. krusadensis Fauvel, 1929, and P. membranacea Imajima, 1990, were determined for the first time. The inter-specific genetic distances among the congeners of four Prionospio species were 22.3-29.6% in CO1, 10.5-25.0% in 16S rDNA, and 0.3-3.6% in 18S rDNA.