• Bulletin of the Korean Mathematical Society
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• v.50 no.5
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• pp.1711-1723
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• 2013

P. V$\acute{a}$mos called a ring R 2-good if every element is the sum of two units. The ring of all $n{\times}n$ matrices over an elementary divisor ring is 2-good. A (right) self-injective von Neumann regular ring is 2-good provided it has no 2-torsion. Some of the earlier results known to us about 2-good rings (although nobody so called at those times) were due to Ehrlich, Henriksen, Fisher, Snider, Rapharl and Badawi. We continue in this paper the study of 2-good rings by several authors. We give some examples of 2-good rings and their related properties. In particular, it is shown that if R is an exchange ring with Artinian primitive factors and 2 is a unit in R, then R is 2-good. We also investigate various kinds of extensions of 2-good rings, including the polynomial extension, Nagata extension and Dorroh extension.

• Bulletin of the Korean Mathematical Society
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• v.54 no.1
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• pp.159-175
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• 2017

We solve the $Bj{\ddot{o}}rling$ problem for constant mean curvature one surfaces in hyperbolic three-space and in de Sitter three-space. That is, we show that for any regular, analytic (and spacelike in the case of de Sitter three-space) curve ${\gamma}$ and an analytic (timelike in the case of de Sitter three-space) unit vector field N along and orthogonal to ${\gamma}$, there exists a unique (spacelike in the case of de Sitter three-space) surface of constant mean curvature 1 which contains ${\gamma}$ and the unit normal of which on ${\gamma}$ is N. Some of the consequences are the planar reflection principles, and a classification of rotationally invariant CMC 1 surfaces.

• Journal of architectural history
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• v.11 no.4 s.32
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• pp.45-69
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• 2002

This study aims to find out the genetic characteristics of gridded subdivision area which has its origin from ancient local administrative city-Sangju, Jeonju, Namwon, Kwangju, Chungju. The spatial structure, based on the inter-relationship among gridded subdivision area, city wall, and topographic condition, and the morphological characteristics of gridded subdivision area are analyzed. The points of analysis on morphological characteristics of gridded subdivision area consist of the size of unit block, the organization system of unit block, the orientation of subdivision line. As a result of the analysis, three main characteristics are found. Firstly there can be found no same land subdivision rule among study areas. Secondly, the morphological features of study area were the products of cumulative process of different subdivision areas which were developed in different periods. Thirdly, the original regular gridded land subdivision seems to have been carried out in the object of a farm-land cultivation around 7th century. And there was a change of land-use from farm land to urban land-use during the later 7th century and 8th century.

• Fashion & Textile Research Journal
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• v.4 no.4
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• pp.399-404
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• 2002

The purpose of this study was to develop the rain melange fabrics with using the pulsar interlacing unit. The properties of the pulsar interlaced yarns (PI yarn) which were textured with the several texturing conditions were analyzed and compared with the regular interlaced yarn (IT yarn) and with normally composited yarn (CP yarn). The results were as follows : The PI yarn which has the best rain random melange effect could be obtained with following texturing condition; 3 kg/$cm^2$ of interlacing air pressure, 1.6 mm diameter of interlacing nozzle and 500 m/min of yarn speed. When IT yarn was compared with CP yarn, IT yarn had higher denier and tenacity than those of CP yarn and had lower elongation and shrinkage than those of CP yarn.

• Speech Sciences
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• v.14 no.2
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• pp.139-155
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• 2007

Old Korean regulated poems have a typical prosodic structure characterized by a pitch contour. This work applies Jun's finding in Seoul Korean(Jun 1993, 2000, 2005) to old Korean regulated poems, and reports some other significant phonetic characteristics, arguing that old Korean regulated poems have a regular rhythm based on the pitch contour implementing the typically hierarchical prosodic structure. The major prosodic units defined are a foot, a phrase, and a line. Next, this work proposes pitch contour characterizing prominence in a unit, boundary tones, and pauses at the boundary position, as the basic and significant cues of rhythm of a Korean poem. Specifically, some significant characteristics are discussed as follows: first, the tonal pattern of a foot is HL, starting high and ending low; second, the lowering boundary tones of HL% and L% are perceived at the end of a phrase and a line; and finally, a gradient degree of pause is observed at each unit-final position.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.58.4-58.4
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• 2019

We present the application of the Point Spread Function (PSF) deconvolution method to the astronomical Integral Field Unit (IFU) Spectroscopy data focus on the restoration of the galaxy kinematics. We apply the Lucy-Richardson deconvolution algorithm to the 2D image at each wavelength slice. We make a set of mock IFU data which resemble the IFU observation to the model galaxies with a diverse combination of surface brightness profile, S/N, line-of-sight geometry and Line-Of-Sight Velocity Distribution (LOSVD). Using the mock IFU data, we demonstrate that the algorithm can effectively recover the stellar kinematics of the galaxy. We also show that lambda_R_e, the proxy of the spin parameter can be correctly measured from the deconvolved IFU data. Implementation of the algorithm to the actual SDSS-IV MaNGA IFU survey data exhibits the noticeable difference on the 2D LOSVD, geometry, lambda_R_e. The algorithm can be applied to any other regular-grid IFS data to extract the PSF-deconvolved spatial information.

• Journal of Neurocritical Care
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• v.11 no.2
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• pp.81-85
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• 2018

Proper glucose management in hospitalized patients can improve clinical outcomes. In particular, intensive care unit (ICU) patients are known to have significantly higher rates of mortality from changes in blood glucose due to severe comorbidities. Improving glucose control in ICU patients, therefore, can improve mortality and prognosis. Several studies related to the management of blood glucose in the ICU patients have been conducted. Intensive glucose management of surgical ICU patients has been successful. However, studies on medical ICU patients did not demonstrate positive effects of strict glycemic control. There is no independent glucose management goal for neurological ICU patients. However, maintenance of the usual glucose control target of 140-180 mg/dL is recommended for ICU patients. Intravenous insulin infusion is essential for glucose control in ICU patients not consuming a regular diet, and caution should be exercised to prevent hypoglycemia.

• Kyungpook Mathematical Journal
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• v.62 no.2
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• pp.213-227
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• 2022

We discuss the relation between units and nilpotents of a ring, concentrating on the transitivity of units on nilpotents under regular group actions. We first prove that for a ring R, if U(R) is right transitive on N(R), then Köthe's conjecture holds for R, where U(R) and N(R) are the group of all units and the set of all nilpotents in R, respectively. A ring is called right UN-transitive if it satisfies this transitivity, as a generalization, a ring is called unilpotent-IFP if aU(R) ⊆ N(R) for all a ∈ N(R). We study the structures of right UN-transitive and unilpotent-IFP rings in relation to radicals, NI rings, unit-IFP rings, matrix rings and polynomial rings.

• Safety and Health at Work
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• v.10 no.4
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• pp.527-530
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• 2019

The increasing prevalence of inactivity and obesity, along with aging, has implications on work capacity of labor force. This study reports the relationships between activity level and BMI by age with objectively measured physical workload. Data were examined from a sample of 19 481 Finnish employees using an estimate of minute-to-minute oxygen consumption based on R-R interval recordings. The mean estimated %VO₂max during the working day was 12.1 (±3.6) and 15.1 (±4.5)% for men and women, respectively. Based on a linear model, the mean %VO₂max increased by 1.5%-unit per 10-year increase in age, by 2.1%-unit per 5 kg/㎡ increase in BMI, and decreased by 1.6%-unit if improving physical activity class by two (p < 0.001 for all). Overweight and obesity, together with inactivity, notably increases workload throughout the career, even though at young adulthood, the daily workload is almost the same for each person regardless of the BMI, activity level, or gender. This study highlights the importance of regular physical activity and normal weight in protecting the worker from excessive physical (cardiovascular) workload during the whole working career.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.21 no.4
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• pp.413-422
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• 2014

Purpose: The purpose of this study was to identify the nutrition-related factors influencing the prevalence of pressure ulcers among patients admitted to an intensive care unit. Methods: Research participants were 112 patients who were admitted to the ICU of a university hospital. Data were collected through questionnaires which included general characteristics, diet-related characteristics, nutritional status, and pressure ulcer status. Multivariate logistic regression was used to identify independent factors association with prevalence of pressure ulcer Results: The prevalence of pressure ulcers was 58 patients (51.8%) at 10th day after ICU admission. In multivariate analysis, prevalence of pressure ulcers at 10th day in ICU was significantly higher in the nutritional risk group (OR=6.43), malnutrition group (OR=88.02), and deceased serum albumin group (OR=28.83). Conclusion: The results of this research indicate that scores on MNA (Mini Nutritional Assessment) and serum albumin were significant predictors of pressure ulcer prevalence in ICU patients. Therefore, regular MNA-SF and albumin checkups are needed to identify risk for pressure ulcer for ICU patients. In the case of decreased MNA-SF scores and serum albumin levels, more intensive pressure ulcer care is needed for ICU patients.