• 한국경영과학회지
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• 제10권2호
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• pp.45-53
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• 1985

In the present paper, the capacitated solid transportation problem (planar constraints) is considered with upper and lower bounds on the rim conditions. The considered model has been shown to be equipvalent to a standard capacitated 3-index transportation problem. A procedure to solve any capacitated 3-index transportion problem is also suggested. Some special cases of the considered model have been shown to conform to possible practical situations.

• Bulletin of the Korean Chemical Society
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• 제14권1호
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• pp.79-81
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• 1993

Synthetic routes are described for the introduction of hydroxyalkyl groups to the upper rim of calix[4]arene. Treatment of p-bromocalix[4]arene methyl ether 3 with n-BuLi followed by para-formaldehyde produced p-hydroxymethylcalix[4]arene methyl ether 4 in 60% yield. p-Acetylcalix[4]arene methyl ether 7, obtained by Friedel-Crafts acetylation of calix[4]arene methyl ether 6, was reduced with NaBH4 to produce p-(1-hydroxy ethyl)calix[4]arene methyl ether 8 in 67% yield.

• Bulletin of the Korean Chemical Society
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• 제17권6호
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• pp.525-528
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• 1996

Seven cali[4]arenes, having two different substituents in AAAB or AABB pattern at the upper rim of calix were synthesized by fragmentation condensation reaction of p-substituted phenol trimer (AAA) with 2,6-bishydroxymethylated 4-substituted phenol (B) or that of dimer (AA) with 2,2'-bishydroxymethylated dimer (BB). An equimolar mixture of the coupling components (trimer and monomer or dimer and dimer) was refluxed in dioxane in the presence of TiCl4to afford calix[4]arene 6 and 7 in 15-38% yield. The structure of calix[4]arenes was confirmed by elemental analysis and the 1H/13C NMR spectroscopy.

• Bulletin of the Korean Chemical Society
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• 제16권11호
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• pp.1122-1125
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• 1995

Three inherently chiral calix[4]arenes 3-5 were synthesized as racemate starting from the ethylation at 1.3-distal hydroxy groups of calix[4]arene 2 which has two phenyl groups at upper rim in AABB fashion, and then two remaining hydroxy groups were acetylated by treatment with acetyl chloride in the presence of NaH to produce calix[4]arene 4. Treatment of 4 with AlCl3 under Fries rearrangement conditions, only one acetyl group was rearranged to the para-position to afford calix[4]arene 5 with AABC substitution pattern at the upper rim of calix. The structure of chiral calix[4]arenes were confirmed based on NMR and massspectra.

• Korean Journal of Radiology
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• 제22권4호
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• pp.663-671
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• 2021

Objective: To determine the association of macrocalcification and rim calcification with malignancy and to stratify the malignancy risk of thyroid nodules with macrocalcification and rim calcification based on ultrasound (US) patterns. Materials and Methods: The study included a total of 3603 consecutive nodules (≥ 1 cm) with final diagnoses. The associations of macrocalcification and rim calcification with malignancy and malignancy risk of the nodules were assessed overall and in subgroups based on the US patterns of the nodules. The malignancy risk of the thyroid nodules was categorized as high (> 50%), intermediate (upper-intermediate: > 30%, ≤ 50%; lower-intermediate: > 10%, ≤ 30%), and low (≤ 10%). Results: Macrocalcification was independently associated with malignancy in all nodules and solid hypoechoic (SH) nodules (p < 0.001). Rim calcification was not associated with malignancy in all nodules (p = 0.802); however, it was independently associated with malignancy in partially cystic or isoechoic and hyperechoic (PCIH) nodules (p = 0.010). The malignancy risks of nodules with macrocalcification were classified as upper-intermediate and high in SH nodules, and as low and lower-intermediate in PCIH nodules based on suspicious US features. The malignancy risks of nodules with rim calcification were stratified as low and lower-intermediate based on suspicious US features. Conclusion: Macrocalcification increased the malignancy risk in all and SH nodules with or without suspicious US features, with low to high malignancy risks depending on the US patterns. Rim calcification increased the malignancy risk in PCIH nodules, with low and lower-intermediate malignancy risks based on suspicious US features. However, the role of rim calcification in risk stratification of thyroid nodules remains uncertain.

• Bulletin of the Korean Chemical Society
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• 제19권4호
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• pp.492-495
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• 1998

• Bulletin of the Korean Chemical Society
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• 제20권9호
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• pp.1108-1110
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• 1999

• 마이크로전자및패키징학회지
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• 제15권4호
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• pp.31-39
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• 2008

캐비티 형성이 불필요한 MEMS 캡 본딩을 위해 전기도금법을 이용하여 Cu/Sn rim 구조를 형성하였으며, $25{\sim}400{\mu}m$ 범위의 rim 폭에 따른 본딩특성을 분석하였다. Cu/Sn rim의 폭이 증가함에 따라 rim 패키지 내부의 유효 실장면적비가 감소하는 반면에 파괴하중비가 증가하며, Cu/Sn rim 폭이 150 ${\mu}m$일 때 유효 실장면적비와 파괴하중비를 최적화할 수 있을 것으로 예측되었다. 폭 25 ${\mu}m$ 및 폭 50 ${\mu}m$인 Cu/Sn rim 접합부에서는 모든 계면에서 본딩이 이루어진 반면에, 100 ${\mu}m$ 이상의 폭을 갖는 rim 접합부에서는 Sn 도금표면의 거칠기에 의해 본딩이 이루어지지 않은 기공 부위가 관찰되었다.

• Bulletin of the Korean Chemical Society
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• 제19권2호
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• pp.207-211
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• 1998

Potentiometric characteristics of DOS plasticized PVC-based membranes containing upper-rim calix[4]crown neutral carrier to various metal cations and protonated alkylamines have been examined. Although the calix[4]crown-based membrane electrodes exhibited substantial emf responses to alkali and alkaline earth metal cations, their high detection limits (- log[Cs+]=4.5) and sub-Nernstian response slopes (48 mV/pCs+) to the most selective cation, cesium, indicate that the metal cation complexing ability of calix[4]crown is much weaker than that of macrocyclic crown ethers. However, the calix[4]crown-based membrane electrodes exhibited near-Nernstian response slopes (56 mV/decade for hexylNH3+) with low detection limits (log[hexylNH3+]= - 6.7) to most alkylammonium ions compared to those of blank (DOS plasticized PVC membrane with no ionophore) or crown ether-based membranes. While the selectivity patterns of blank and crown ether-based membranes are determined primarily by the lipophilicity of alkylammonium ions, the membranes doped with calix[4]crown ionophore could effectively discriminate the steric shapes of nonpolar alkyl groups of alkylammonium ions.

• Bulletin of the Korean Chemical Society
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• 제22권7호
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• pp.782-784
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• 2001