• Korean Journal of Materials Research
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• v.26 no.2
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• pp.100-108
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• 2016

Zinc Sulfide (ZnS) is one of the II-VI semiconducting materials, having novel fundamental properties and diverse areas of application such as light-emitting diodes (LEDs), electroluminescence, flat panel displays, infrared windows, catalyst, chemical sensors, biosensors, lasers and biodevices, etc. However, despite the remarkable versatility and prospective potential of ZnS, research and development (R&D) into its applications has not been performed in much detail relative to research into other inorganic semiconductors. In this study, based on global patent information, we analyzed recent technical trends and the current status of R&D into ZnS applications. Furthermore, we provided new technical insight into ZnS applicable fields using in-depth analysis. Especially, this report suggests that ZnS, due to its infrared-transmitting optical property, is a promising material in astronomy and military fields for lenses of infrared systems. The patent information analysis in this report will be utilized in the process of identifying the current positioning of technology and the direction of future R&D.

• Restorative Dentistry and Endodontics
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• v.12 no.2
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• pp.111-116
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• 1987

The experimental study was made to evaluate the influence of retentive grooves on the canal wall upon the retention of post, using different type of cements. Ninety periodontally involved anterior teeth were extracted and divided into six groups of 15 teeth. The groups were labeled as follows: Group I: Dentatus post cemented zincphosphate cement into post hole with smooth wall. Group II: Dentatus post cemented with zincphosphate cement into post hole with retentive grooves. Group III: Dentatus post cemented with glass-ionomer cement into post hole with smooth wall. Group IV: Dentatus post cemented with glass-ionomer cement into post hole with retentive grooves. Group V: Dentatus post cemented with composite resin adhesive into post hole with smooth wall. Group VI: Dentatus post cemented with composite resin adhesive into post hole with retentive grooves. The tensile strength was tested by an Instron type tester with cross-head speed of 5mm per minute. The results were as follows: In the group without retentive grooves, three kinds of cement have little effect upon retentive capacity of Dentatus post. The Dentatus post cemented on the canal wall with retentive grooves is more retentive than Dentatus post without retentive grooves.

• Korean Journal of Remote Sensing
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• v.26 no.6
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• pp.617-627
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• 2010

Although many researches for heat island study have been developed, there is little attempt to link the findings to actual and hypothetical scenarios of urban developments which would help to mitigate the Urban Heat Island (UHI) in cities. The aim of this paper is to analyze the UHI at urban area with different geometries, land use, and environmental factors, and emphasis on the influence of different geometric and environmental parameters on ambient air temperature. In order to evaluate these effects, the parameters of (i) Air pollution (i.e. Aerosol Optical Thickness (AOT)), (ii) Green space Normalized Difference Vegetation Index (NDVI), (iii) Anthropogenic heat (AH) (iv) Building density (BD), (v) Building height (BH), and (vi) Air temperature (Ta) were mapped. The optimum operational scales between Heat Island Intensity (HII) and above parameters were evaluated by testing the strength of the correlations for every resolution. The best compromised scale for all parameters is 275m resolution. Thus, the measurements of these parameters contributing to heat island formation over the study areas of Hong Kong were established from mathematical relationships between them and in combination at 275m resolution. The mathematical models were then tabulated to show the impact of different percentages of parameters on HII. These tables are useful to predict the probable climatic implications of future planning decisions.

• YAKHAK HOEJI
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• v.13 no.2_3
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• pp.62-66
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• 1969

Ten new N$^{4}$-furoylsulfonamides were synthesized such as N$^{4}$-furoyl-N$^{1}$-(4,6-dimethyl-2-pyrimidinyl) sulfanilamide (I), N$^{4}$-furoylsulfanilamide (II), N$^{4}$-furoyl-N$^{1}$-(2,6-dimethoxy-4-pyrimidinyl) sulfanilamide (III), N$^{4}$-furoyl-N$^{1}$-(4-methyl-2-pyrimidinyl) sulfanilamide (IV), N$^{4}$-furoyl-N$^{1}$-(6-methoxy-3-pyridazinyl) sulfanilamide (V), N$^{4}$-furoyl-N$^{1}$-2-pyrimidinylsulfanilamide (VI), N$^{4}$-furoyl-N$^{1}$-(3,4-dimethyl-5-isoxazolyl) sulfanilamide (VII), N$^{4}$-furoyl-N$^{1}$-2-thiazoilysulfanilamide (VIII), N$^{4}$-furoyl-N$^{1}$-(5-methoxy-2-pyrimidinyl) sulfanilamide (IX) and N$^{4}$-furoyl-N$^{1}$-(2,6-dimethyl-4-pyrimidinyl) sulfanilamide (X). They were obtained by the action of N$^{1}$-(4,6-dimethyl-2-pyrimidinyl) sulfanilamide, N$^{1}$-(2,6-dimethoxy-4-pyrimidinyl) sulfanilamide, N$^{1}$-(4-methyl-2-pyrimidinyl) sulfanilamide, N$^{1}$-(6-methoxy-3-pyridazinyl) sulfanilamide, N-2-pyrimidinyl sulfanilamide, N$^{1}$-(3,4-dimethyl-5-isoxazolyl) sulfanilamide, N$^{1}$-2-(thiazolysulfanilamide), N$^{1}$-(5-methoxy-2-pyrimidinyl) sulfanilamide and N$^{1}$-(2,6-dimethyl-4-pyrimidinyl) sulfanilamide with furoyl chloride in 4% NaOH solution. Of the above ten compounds, N$^{4}$-furoylsulfathiazole exhibited a good antibacterial action against Staphylococeus aureus and Escherichia coli.

• Kyungpook Mathematical Journal
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• v.59 no.1
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• pp.1-11
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• 2019

Let R be a prime ring with involution of the second kind and centre Z(R). Suppose R admits a generalized derivation $F:R{\rightarrow}R$ associated with a derivation $d:R{\rightarrow}R$. The purpose of this paper is to study the commutativity of a prime ring R satisfying any one of the following identities: (i) $F(x){\circ}x^*{\in}Z(R)$ (ii) $F([x,x^*]){\pm}x{\circ}x^*{\in}Z(R)$ (iii) $F(x{\circ}x^*){\pm}[x,x^*]{\in}Z(R)$ (iv) $F(x){\circ}d(x^*){\pm}x{\circ}x^*{\in}Z(R)$ (v) $[F(x),d(x^*)]{\pm}x{\circ}x^*{\in}Z(R)$ (vi) $F(x){\pm}x{\circ}x^*{\in}Z(R)$ (vii) $F(x){\pm}[x,x^*]{\in}Z(R)$ (viii) $[F(x),x^*]{\mp}F(x){\circ}x^*{\in}Z(R)$ (ix) $F(x{\circ}x^*){\in}Z(R)$ for all $x{\in}R$.

• Korean Journal of Plant Taxonomy
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• v.49 no.1
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• pp.1-7
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• 2019

Early leaves within the Viola albida complex were investigated by scanning electron microscopy in order to determine the morphological segments during morphogenesis. The early leaf development of V. albida var. albida could be morphologically divided into the eight stages in the following order: I, the initiation of shoot germination; II, the conical growth directionally of the leaf; III, the adaxial and abaxial formation of the leaf; IV, the initiation of the stipule; V, the formation of a transitional zone between the leaf blade and petiole; VI, the expansion of the upper part of the leaf blade; VII, the formation of almost all parts of the early leaf; VIII, the early simple leaf. Viola albida var. takahashii differs from V. albida var. albida by additional stages, i.e., V-1, the initiation of the first lateral lobe at the both lateral parts of the leaf after the stage V and an early lobed leaf. Viola albida var. chaerophylloides is also distinguished from two taxa by two developmental features, V-2, the initiation of a second lateral lobe below of the first lateral lobe, and an early palmately compound leaf. These findings suggest that the Viola albida complex would be in the process of peramorphosis, showing developmental changes in a chain of events, leading to a different leaf shape. These data would also be useful for isolating genes that give rise to different leaf morphogenesis outcomes among the taxa in the Viola albida complex.

• Journal of Hydrogen and New Energy
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• v.31 no.6
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• pp.530-545
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• 2020

This paper reviews and summarizes the fuel-cell-related studies those have been recently published in major Korean Citation Index journals, aiming at analyzing the research trend in fuel cell technologies. Six major journals are selected for the literature survey; 57 papers are chosen for the detailed analysis through a screening examination on the total 1,040 papers published during between 2018 and 2020. Papers are classified into six technical categories, such as i) electrode, ii) electrolyte, iii) bipolar plate and stack, iv) fuel cell system, v) balance of plant, and vi) diagnosis-related studies, and summarized by the experts in the relevant area. Through this paper, we provide a comprehensive review on the recent trends and progress in fuel-cell-related research work in Korea.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.2
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• pp.193-207
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• 2022

The purpose of this study was to find out what factors influence the preparation of financial statements in accordance with the International Financial Reporting Standards (IFRS) for Vietnamese businesses. The survey included 150 enterprises, including parent companies of state-owned economic groups, parent companies that are listed companies, large-scale public companies that are unlisted parent companies, and enterprises with 100 percent foreign direct investment, that will apply IFRS voluntarily from the year 2022 and switch to the mandatory application from the year 2025 (Ministry of Finance, 2016). The survey was carried out with the help of the Google Form tool, and the data was processed using EFA and regression analysis methods on the SPSS 22.0 software. The findings show, for enterprises in Vietnam, that six factors influence the preparation of financial statements in accordance with IFRS, ranked in order of influence from high to low: (i) Related party requirements; (ii) Professional qualifications of accountants; (iii) Roles of enterprise managers; (iv) Forms of capital ownership in enterprises, (v) Institutional regulations, and (vi) Operational characteristics of the enterprise. In addition, the study also shows that, for enterprises in Vietnam, the requirements of related parties are an important factor to promote the preparation of the financial statements of enterprises according to IFRS.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.662-666
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• 2005

Using data gathered from expert opinion of plant and equipment professionals; this paper presents the key variables that may constitute a maintenance proficient plant operator. The Multivariate Discriminant Analysis (MDA) was applied to generate data and was tested for sensitivity analysis. Results showed that the MDA model was able to classify plant operators' proficiency at 94.10 percent accuracy and determined nine (9) key variables of a maintenance proficient plant operator. The key variables included: i) number of years of experience as equipment operator (PQ1); ii) eye-hand coordination (PQ9); iii) eye-hand-foot coordination (PQ10); iv) planning skills (TE16); v) pay/wage (MQ1); vi) work satisfaction (MQ4); vii) operator responsibilities as defined by management (MF1); viii) clear management policies (MF4); and ix) management pay scheme (MF5). The classification procedure of nine variables formed the general model with the equation viz: OMP (general) = 0.516PQ1 + 0.309PQ9 + 0.557PQ10 + 0.831TE16 + 0.8MQ1 + 0.0216MQ4 + 0.136MF1 + 0.28MF4 + 0.332MF5 - 4.387

• Applied Microscopy
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• v.50
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• pp.18.1-18.7
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• 2020

The olfactory anatomy and histology of Lethenteron reissneri were researched using a stereo microscope, a light microscope, and a scanning electron microscope. As in other lampreys, it shows same characters as follows: i) a single olfactory organ, ii) a single tubular nostril, iii) a single olfactory chamber with gourd-like form, iv) a nasal valve, v) a nasopharyngeal pouch, vi) a sensory epithelium (SE) of continuous distribution, vii) a supporting cells with numerous long cilia, viii) an accessory olfactory organ. However, the description of a pseudostratified columnar layer in the SE and Non SE is a first record, not reported in sea lamprey Petromyzon marinus. In particular, both 19 to 20 lamellae in number and olfactory receptor neuron's quarter ciliary length of the knob diameter differ from those of P. marinus. From these results, it might be considered that the olfactory organ of L. reissneri shows well adaptive structure of a primitive fish to slow flowing water with gravel, pebbles, and sand and a hiding habit into sand bottom at daytime. The lamellar number and neuron's ciliary length may be a meaningful taxonomic character for the class Petromyzonida.