• Mass Spectrometry Letters
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• v.6 no.4
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• pp.99-104
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• 2015

A liquid chromatography mass spectrometry (LC-MS) system was used to identify and distinguish oligostilbene diastereoisomers. A polyphenolic extract from Neobalanocarpus heimii known to be rich in oligostilbenes of various degrees of condensation was used as test material. Fourteen oligostilbenes were isolated from this extract on a fully automated semi-preparative HPLC system. Out of these, two pairs of dimers, one pair of trimers, two pairs of tetramers and a group of four tetramers with similar skeleton were identified as diastereoisomers. Their structures and configurations were established by spectroscopic methods. All isolated compounds were subjected to an LC-MS/MS to study their fragmentation patterns. The experiments were performed on a liquid chromatography-mass spectrometry (LC-MS) with electrospray-ionization (ESI) interface in positive mode. MS/MS spectra of each pure compound were recorded by direct infusion in identical conditions and their product ion spectra were analysed. Some subtle yet significant differences were observed between the spectra of oligostilbenes from the various diastereoisomeric series.

• Bulletin of the Korean Mathematical Society
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• v.46 no.1
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• pp.135-146
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• 2009

In the present note we study the properties of weak Armendariz rings, and the connections among weak Armendariz rings, Armendariz rings, reduced rings and IFP rings. We prove that a right Ore ring R is weak Armendariz if and only if so is Q, where Q is the classical right quotient ring of R. With the help of this result we can show that a semiprime right Goldie ring R is weak Armendariz if and only if R is Armendariz if and only if R is reduced if and only if R is IFP if and only if Q is a finite direct product of division rings, obtaining a simpler proof of Lee and Wong's result. In the process we construct a semiprime ring extension that is infinite dimensional, from given any semi prime ring. We next find more examples of weak Armendariz rings.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.2
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• pp.264-270
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• 1997

To obtain basic data for processing semi-dried salmon meat product, the results that were measured the textural properties of salmon meat during salting, sugaring and drying process followed. Drying time and temperature were longer, the moisture amount of salmon meat were reduced. Hardness of salmon meat was direct proportion to shear stress, but hardness was inverse proportion to cohesiveness during drying process. After sugaring and salting salmon meat, drying time was longer, hardness and shear stress of salmon meat were increased. The sensory evaluation of the textures of sugaring salmon meat dried for 3 hrs showed slightly good. In the changes of texture of salmon meat during steaming hardness and shear stress of salmon meat dried for 4 hrs were higher than that dried for 10 hrs. And steaming time was longer, hardness of salmon meat dried for 4 hrs was decreased and cohesiveness was not changed.

• Korean Chemical Engineering Research
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• v.45 no.3
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• pp.249-257
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• 2007

The periodic square wave (PSW) model was successfully applied to the optimal design of a batch-storage network. The network structure can cover any type of batch production, distribution and inventory system, including recycle streams. Here we extend the coverage of the PSW model to multitasking semi-continuous processes as well as pure continuous and batch processes. In previous solutions obtained using the PSW model, the feedstock composition and product yield were treated as known constants. This constraint is relaxed in the present work, which treats the feedstock composition and product yield as free variables to be optimized. This modification makes it possible to deal with the pooling problem commonly encountered in oil refinery processes. Despite the greater complexity that arises when the feedstock composition and product yield are free variables, the PSW model still gives analytic lot sizing equations. The ability of the proposed method to determine the optimal plant design is demonstrated through the example of a high density polyethylene (HDPE) plant. Based on the analytical optimality results, we propose a practical process optimality measure that can be used for any kind of process. This measure facilitates direct comparison of the performance of multiple processes, and hence is a useful tool for diagnosing the status of process systems. The result that the cost of a process is proportional to the square root of average flow rate is similar to the well-known six-tenths factor rule in plant design.

• Journal of the Korea Safety Management & Science
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• v.21 no.4
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• pp.67-74
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• 2019

Visual inspection is regarded as one of the critical activities for quality control in a manufacturing company. it is thus important to improve the performance of detecting a defective part or product. There are three probable working modes for visual inspection: fully automatic (by automatic machines), fully manual (by human operators), and semi-automatic (by collaboration between human operators and automatic machines). Most of the current studies on visual inspection have been focused on the improvement of automatic detection performance by developing a better automatic machine using computer vision technologies. However, there are still a range of situations where human operators should conduct visual inspection with/without automatic machines. In this situation, human operators'performance of visual inspection is significant to the successful quality control. However, visual inspection of components assembled into a mobile camera module belongs to those situations. This study aims to investigate human performance issues in visual inspection of the components, paying more attention to human errors. For this, Abstraction Hierarchy-based work domain modeling method was applied to examine a range of direct or indirect factors related to human errors and their relationships in the visual inspection of the components. Although this study was conducted in the context of manufacturing mobile camera modules, the proposed method would be easily generalized into other industries.

• Journal of Fashion Business
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• v.22 no.5
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• pp.15-31
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• 2018

The purpose of this study was to classify male consumers and examine their clothing consumption values and the perceived importance of store attributes. Using Internet-based research service, survey data were collected from 651 male consumers aged between 20 and 40. The questionnaire included questions regarding respondents' preference of different store types, clothing consumption values, perceived importance of store attributes. According to the results, the respondents were categorized into 5 distinct groups based on their store type preferences: discount store preference group, multi-channel preference group, store indifferent group, brand store preference group, online store preference group. Multi-channel preference group was the largest among these groups. The five store type preference groups statistically varied in clothing consumption values, i.e., epistemic value, brand/conspicuous value, and economic value. The groups also differed in the importance they placed in the store attributes of: service and product quality, promotion, fashionability, salesperson and store environment, store atmosphere, convenience, and website image. The results of this study have direct implication for retail marketers of fashion companies who are targeting male consumers. Marketers can apply findings of this study in implementing retail strategies for different types of stores.

• The Journal of Internal Korean Medicine
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• v.41 no.1
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• pp.14-28
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• 2020

Objectives: The aim of this study was to analyze consumer experience with Digestive Enzymes, a digestive enzyme product that includes medicinal herbs (Multi-Zyme^®). The goal was to provide basic data on improvements and marketability of future digestive enzyme products containing medicinal herbs. Methods: Qualitative research was conducted to explore the current participants' experience. In-depth interviews with a semi-structured interview guide were conducted to investigate the experience and perception of the participants. The participants were recruited using snowball sampling and purposive sampling, and a qualitative content analysis method was adopted. Credibility was ensured by adopting a member check, triangulation, and peer debriefing method. Results: In-depth interviews were completed with a total of 8 participants. The collected data were classified into 16 codes and then further divided into the following seven categories: direct buying, indirect buying, effects, questions, recommendations, positive perception, and negative perception. The categories were grouped into three themes: 'Experience of purchasing existing health foods', 'Experience of taking Multi-Zyme', and 'Opinions on selling Multi-Zyme at Korean medicine clinics'. Conclusion: The participants experienced effect of the Multi-Zyme^® and were willing to recommend it around. However, the Korean medicine doctors need to inform consumers about the dose and duration when taking Multi-Zyme^® to prevent abuse. Some consumers may trust Multi-Zyme^® sales from Korean medicine clinics, but some held opinions that those sales were not trustworthy, so promotion and improvement are needed.

• Korean Journal of Remote Sensing
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• v.37 no.3
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• pp.449-461
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• 2021

Analysis Ready Data (ARD) for optical satellite images represents a pre-processed product by applying spectral characteristics and viewing parameters for each sensor. The atmospheric correction is one of the fundamental and complicated topics, which helps to produce Top-of-Atmosphere (TOA) and Top-of-Canopy (TOC) reflectance from multi-spectral image sets. Most remote sensing software provides algorithms or processing schemes dedicated to those corrections of the Landsat-8 OLI sensors. Furthermore, Google Earth Engine (GEE), provides direct access to Landsat reflectance products, USGS-based ARD (USGS-ARD), on the cloud environment. We implemented the Orfeo ToolBox (OTB) atmospheric correction extension, an open-source remote sensing software for manipulating and analyzing high-resolution satellite images. This is the first tool because OTB has not provided calibration modules for any Landsat sensors. Using this extension software, we conducted the absolute atmospheric correction on the Landsat-8 OLI images of Railroad Valley, United States (RVUS) to validate their reflectance products using reflectance data sets of RVUS in the RadCalNet portal. The results showed that the reflectance products using the OTB extension for Landsat revealed a difference by less than 5% compared to RadCalNet RVUS data. In addition, we performed a comparative analysis with reflectance products obtained from other open-source tools such as a QGIS semi-automatic classification plugin and SAGA, besides USGS-ARD products. The reflectance products by the OTB extension showed a high consistency to those of USGS-ARD within the acceptable level in the measurement data range of the RadCalNet RVUS, compared to those of the other two open-source tools. In this study, the verification of the atmospheric calibration processor in OTB extension was carried out, and it proved the application possibility for other satellite sensors in the Compact Advanced Satellite (CAS)-500 or new optical satellites.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.4
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• pp.337-343
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• 2009

Purpose: ((R)-1-(2-chlorophenyl)-N-1-[$^{11}$C]methyl-N(1-propyl)-3-isoquinoline carboxamide ((R)-PK11195) is a specific ligand for the peripheral type benzodiazepine receptor and a marker of activated microglia, used to measure inflammation in neurologic disorders. We report here that a direct and simple radiosynthesis of [$^{11}$C](R)-PK11195 in mild condition using NaH suspension in DMF and one-step loop method. Materials and Methods: (R)-N-Desmethyl-PK11195 (1 mg) in DMSO (0.1 mL) and NaH suspension in DMF (0.1 mL) were injected into a semi-prep HPLC loop. [$^{11}$C]methyl iodide was passed through HPLC loop at room temperature. Purification was performed using semi-preparative HPLC. Aliquots eluted at 11.3 min were collected and analyzed by analytical HPLC and mass spectrometer. Results: The labeling efficiency of [$^{11}$C](R)-PK11195 was 71.8$\pm$8.5%. The specific activity was 11.8:$\pm$6.4 GBq/$\mu$mol and radiochemical purity was higher than 99.2%. The mass spectrum of the product eluted at 11.3 min showed m/z peaks at 353.1 (M+1), indicating the mass and structure of (R)-PK11195. Conclusion: By the one-step loop method with the [$^{11}$C]CH3l automated synthesis module, [$^{11}C$](R)-PK11195 could be easily prepared in high radiochemical yield using NaH suspension in DMF.