• Mass Spectrometry Letters
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• v.5 no.2
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• pp.49-51
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• 2014

The effectiveness of tertiary matrices composed of the combination of three common matrices (dihydrobenzoic acid (DHB), ${\alpha}$-cyano-4-hydroxycinnamic acid (CHCA), and sinapinic acid (SA)) was compared with that of single or binary matrices in the analysis of polyethylene glycol (PEG) polymers ranging from 1400 to 10000 Da using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). A tertiary matrix of 2,5-DHB+CHCA+SA was the most effective in terms of S/N ratios. CHCA and CHCA+SA produced the highest S/N ratios among the single matrices and the binary matrices, respectively. The improvement observed when using a tertiary matrix in analyses of PEG polymers by MALDI-TOF MS is believed to be due to the uniform morphology of the MALDI sample spots and synergistic effects arising from the mixture of the three matrix materials.

• Applied Chemistry for Engineering
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• v.1 no.2
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• pp.147-153
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• 1990

Poly(hydroxypropyl methacrylate) membranes and matrix devices having tertiary amine moiety were prepared by sintering method, and their permeation characteristics were investigated. The water content of this membrane was increased with decreasing the pH of the medium. The permeability of this membrane was increased with decreasing the sintering pressure. Using sintered matrix device 'burst effect' was found at the early stage, and initial insulin release of glucose oxidase immobilized matrix device could be controlled by glucose concentration of the solution.

• Health Policy and Management
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• v.27 no.3
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• pp.229-240
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• 2017

Background: This study purposed to analyze the spatial accessibility of women in childbearing age to the healthcare organizations (HCOs) providing delivery services in Gangwon-do. Methods: Network analysis was applied to assess the spatial accessibility based on the travel time and road travel distance. Travel time and travel distance were measured between the location of HCOs and the centroid of the smallest administrative areas, eup, myeon, and dong in Gangwon-do. Korean Transport Database Center provided road network GIS (Geographic Information System) Database in 2015 and it was used to build the network dataset. Two types of network analysis, service area analysis and origin-destination (OD)-cost matrix analysis, applied to the created network dataset. Service area analysis defined all-accessible areas that are within a specified time, and OD-cost matrix analysis measured the least-cost paths from the HCOs to the centroids. The visualization of the number of the HCOs and the number of women in childbearing age on the Ganwon-do map and network analysis were performed with ArcGIS ver. 10.0 (ESRI, Redlands, CA, USA). Results: Twenty HCOs were providing delivery services in Gangwon-do in 2016. Over 50% of the women in childbearing age were aged more than 35 years. Service area analysis found that 89.56% of Gangwon-do area took less than 60 minutes to reach any types of HCOs. For tertiary hospitals, about 74.37% of Gangwon-do area took more than 60 minutes. Except Wonju-si and Hoengseong-gun, other regions took more than 60 minutes to reach the tertiary hospital. Especially, Goseong-gun, Donghae-si, Samcheok-si, Sokcho-si, Yanggu-gun, Cheorwon-gun, and Taebaek-si took more than 100 minutes to the tertiary hospital. Conclusion: This study provided that the accessibility toward the tertiary hospital was limited and it may cause problems in high-risk delivery patients such as over 35 years. Health policy makers will need to handle the obstetric accessibility issues in Gangwon-do.

• Journal of Korean Ophthalmic Optics Society
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• v.4 no.2
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• pp.51-55
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• 1999

The eye movement of the eyeball's center of a rotation can represent with the rotation matrix $R_x$, $R_y$, $R_z$ due to a coordinate axis rotation transformation of Cartesian coordinate, and describes of an abduction, an adduction, an elevation, a depression, an intorsion, an extorsion in principle rotation six forms of the eye. The eye movement from primary eye position to tertiary eye position could be composed with the rotation matrix combination, and by the primary rotation of six and the secondary rotation of eight, could be represented with the extrocular muscle of six. The position of the cornea vertex point or pupil point due to the eye movement can describe to transform the rotation matrix of the cartesian coordinate to spherical coordinate$(r,{\theta},{\phi})$.

• Applied Chemistry for Engineering
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• v.16 no.1
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• pp.117-122
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• 2005

The aim of this study was to evaluate the effect of tertiary amine photo-accelerator on the dental properties of visible light-activated, polymeric, dental restorative composites (PDRC) through the measurement of mechanical and esthetic properties. The surface of barium silicate was hydrophobically treated to improve the interfacial behavior with the acrylic resin matrix. Camphorquinone was adopted as a photo-initiator with 0.5 wt% based on the resin matrix. It was discovered that the dental properties of PDRC were primarily dependent on the chemical structure rather than the added content of photo-accelerator.

• Journal of the Korean Society of Safety
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• v.13 no.4
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• pp.131-136
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• 1998

The creep behavior and failure mechanism of the 30 vol% hot-pressed $SiC_t/Si_3N_4$ ceramic composite was experimentally investigated at $1200^{\circ}C$ and at various stress levels in air. The creep threshold stress for zero creep rate after 100 hr was found to be approximately 60 MPa. The stress exponent was estimated to be n~1, which suggests that fiber-reinforcement reduced the stress sensitivity of the HPSN matrix with the stress exponent of 2. The tertiary stage leading to creep rupture was found at 250 MPa but was very short. The microstructure of the crept specimen showed random fiber fracture and no matrix cracking. Interfacial debonding was absent.

• Korean Journal of Metals and Materials
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• v.50 no.7
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• pp.477-485
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• 2012

The effect of aging heat treatment on microstructure evolution of the Ti-6Al-4Fe-0.25Si alloy with an initial microstructure of an elongated alpha was investigated. Aging treatments of the samples were carried out at $550^{\circ}C$ for up to 100 hours. The microstructure of the 5 hours heat-treated sample consisted of alpha grains, beta matrix and some TiFe intermetallic compounds that were precipitated from the beta matrix. Increasing the aging time to 10 hours, most of the beta matrix was decomposed to very fine alpha grains (${\sim}0.5{\mu}m$) and TiFe, and thus the volume fraction of the beta matrix was significantly decreased. EBSD analysis revealed that newly formed tertiary-alpha-grains in the vicinity of TiFe had high angle boundaries with respect to the primary and secondary alpha grains. As a result of these phase transformations during aging, the fraction of the alpha/alpha grain boundary was increased while that of the alpha/beta phase boundary was decreased.

• The Korean Journal of Health Service Management
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• v.13 no.1
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• pp.15-30
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• 2019

Objectives: This study aimed to analyze people's accessibility to medical institutions providing national gastric cancer screening services in Gangwon-do using a geographic information system(GIS). Methods: To assess the spatial accessibility, network analysis was applied. Two types of network analysis-Service area analysis and origin-destination cost matrix(OD-cost matrix)-were applied to create network dataset. Results: The results of the analysis of the service area revealed that it took more than 60 minutes each to reach tertiary hospitals and general hospitals from 74.4% and 9.6% of Gangwon-do areas, respectively. Similarly, it took more than 60 minutes each to reach hospitals and clinics from 4.2% and 3.4% of Gangwon-do areas, respectively. The results of the OD-cost revealed that there were large regional variations in distance and time taken to reach the medical institutions. Conclusions: there were regional variations of spatial accessibility between Si and Gun in Gangwon-do.

• The Journal of the Petrological Society of Korea
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• v.16 no.2 s.48
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• pp.73-81
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• 2007

A basaltic tuff formation (Upper Basaltic Tuff of the Janggi Group) occurs in close association with basalt (Yeonil Basalt) at the Tertiary Janggi basin. The purpose of this paper is to describe the occurrence of the basaltic tuff and associated basalt and to determine their mode of formation. The basaltic rocks of the study area show few distinct lithofacies, all of which are originated from the interaction of basaltic magma with external water. The four lithofacies include (1) sideromelane shard hyaloclastite, (2) pillow breccia, (3) entablature-jointed basalt, and (4) in-situ breccia. The sideromelane shard hyaloclastite constitutes most of the Upper Basaltic Tuff and has a gradual contact with the pillow breccia. The pillow breccia consists of a poorly sorted mixture of isolated and broken pillows, and small basalt globules and fragments engulfed in a volcanic matrix of sideromelane shard hyaloclastite. The entablature-jointed basalt occurs as a small body within the hyaloclastite. It is characterized by irregularly-curved joints known as entablature. The in-situ breccia occurs as a marginal facies of entablature-jointed basalt, and its width varies from 10 to 30m. The result of this study indicates that the basaltic tuff and associated basalts of the study area were produced by the volcanic activity of same period and the basaltic tuff was formed by subaqueous eruption of basaltic lava followed by nonexplosive quench fragmentation.

• The Journal of Engineering Geology
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• v.20 no.2
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• pp.183-189
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• 2010

Fault gouge samples were collected from the fault cores of the boundary faults between the Cretaceous Basement and the Tertiary Waeup Basin. Fractal dimensions (D) were obtained by using survivor grains which were analysed from six thin sections of the gouges under the optical microscope. The elliptical survivor grains show a shape preferred orientation almost parallel to clay foliation in matrix, suggesting that it was formed by the rotation of the survivor grains in abundant fine-grained matrix during repeated fault slips. The size distributions of the survivor grains follow power-laws with fractal dimensions in the 2.40-3.02 range. D values of all samples but one are higher than a specific D value equal to 2.58 which predicts the self similarity of fragmentation process in constrained comminution model (Sammis et al., 1987), which indicates large fault slip and multiple faulting. Probably the higher D values than 2.58 mean the non-self-similar evolution of cataclastic rocks where fragmentation mechanism changed from constrained comminution to the grain abrasion accompanying selective fracture of larger grains.