• Nuclear Medicine and Molecular Imaging
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• v.42 no.6
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• pp.469-477
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• 2008

Purpose: The goal of this paper is to present the design and performance of a position encoding circuit for $16{\times}16$ array of position sensitive multi-anode photomultiplier tube for small animal PET scanners. This circuit which reduces the number of readout channels from 256 to 4 channels is based on a charge division method utilizing a resistor array. Materials and Methods: The position encoding circuit was simulated with PSpice before fabrication. The position encoding circuit reads out the signals from H9500 flat panel PMTs (Hamamatsu Photonics K.K., Japan) on which $1.5{\times}1.5{\times}7.0\;mm^3$ $L_{0.9}GSO$ ($Lu_{1.8}Gd_{0.2}SiO_{5}:Ce$) crystals were mounted. For coincidence detection, two different PET modules were used. One PET module consisted of a $29{\times}29\;L_{0.9}GSO$ crystal layer, and the other PET module two $28{\times}28$ and $29{\times}29\;L_{0.9}GSO$ crystal layers which have relative offsets by half a crystal pitch in x- and y-directions. The crystal mapping algorithm was also developed to identify crystals. Results: Each crystal was clearly visible in flood images. The crystal identification capability was enhanced further by changing the values of resistors near the edge of the resistor array. Energy resolutions of individual crystal were about 11.6%(SD 1.6). The flood images were segmented well with the proposed crystal mapping algorithm. Conclusion: The position encoding circuit resulted in a clear separation of crystals and sufficient energy resolutions with H9500 flat-panel PMT and $L_{0.9}GSO$ crystals. This circuit is good enough for use in small animal PET scanners.

• Journal of Korean Ophthalmic Optics Society
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• v.15 no.1
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• pp.1-7
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• 2010

Purpose: To plan and improve consumers' satisfaction by analyzing consumers' purchasing behavior of spectacles. Also this will show the need of improvement in reliance of an optician. Methods: A total of 307 people (10 to 60 years) participated in individual questionnaires. Questionnaires comprised of general characteristic of surveyed people, purchasing spectacles behavior, satisfaction after purchasing spectacles, reliability of optician, and improvement points of optician. Results: Most important points in selecting the product were the design and the price of the spectacles. 142 people (46.3%) replied "average" and 140 people (45.6%) replied "satisfying" out of maximum point of satisfaction level which was 5 points. 72.3% of people have regularly visiting optical shop due to the high accessibility, after-sales care, and courteous optician. On the contrary, 27.7% replied "never visit same optician shop again" because of the low accessibility, minimal range of products, and high price. Data showed that people had high re liability about the opticians' knowledge of product, and their technique of eye refraction. Data revealed that people did not show high satisfaction about opticians' knowledge of ophthalmology, and price of products. Most important improvement points were accurate spectacle prescription by Opticians rating 42% of reply. Factors most considered during spectacle selection among the 10 to 20 age group were design by 34.8% and price by 10.1%. Among the 40 to 50 age group, most considered factors were design by 14% and spectacle frame material by 10.1%. Conclusions: Satisfaction rate of purchasing spectacles for the total participant group was 4.2 average grades. Reliability of opticians' eye refraction result and prescription was 50.5%. However consumers wanted to obtain more accurate eye refraction result and prescription with more comprehensive explanations. Also, consumers wanted opticians to be sensitive and have appreciative eye in select spectacles for customers, and to offer precise spectacle dispensing services and courteous after-sales care.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.5
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• pp.686-695
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• 2018

Objective: The objective of this study was to investigate the effects of dietary choline supplementation on hepatic lipid metabolism and gene expression in finishing pigs with intrauterine growth retardation (IUGR). Methods: Using a $2{\times}2$ factorial design, eight normal birth weight (NBW) and eight IUGR weaned pigs were fed either a basal diet (NBW pigs fed a basal diet, NC; IUGR pigs fed a basal diet, IC) or a diet supplemented with two times more choline than the basal diet (NBW pigs fed a high-choline diet, NH; IUGR pigs fed a high-choline diet, IH) until 200 d of age. Results: The results showed that the IUGR pigs had reduced body weight compared with the NBW pigs (p<0.05 from birth to d 120; p = 0.07 from d 120 to 200). Increased (p<0.05) free fatty acid (FFA) and triglyceride levels were observed in the IUGR pigs compared with the NBW pigs. Choline supplementation decreased (p<0.05) the levels of FFAs and triglycerides in the serum of the pigs. The activities of malate dehydrogenase and glucose 6-phosphate dehydrogenase were both increased (p<0.05) in the livers of the IUGR pigs. Choline supplementation decreased (p<0.05) malate dehydrogenase activity in the liver of the pigs. Gene expression of fatty acid synthase (FAS) was higher (p<0.05) in the IC group than in the other groups, and choline supplementation decreased (p<0.05) FAS and acetyl-CoA carboxylase ${\alpha}$ expression in the livers of the IUGR pigs. The expression of carnitine palmitoyl transferase 1A (CPT1A) was lower (p<0.05) in the IC group than in the other groups, and choline supplementation increased (p<0.05) the expression of CPT1A in the liver of the IUGR pigs and decreased (p<0.01) the expression of hormone-sensitive lipase in both types of pigs. The gene expression of phosphatidylethanolamine N-methyltransferase (PEMT) was higher (p<0.05) in the IC group than in the other groups, and choline supplementation significantly reduced (p<0.05) PEMT expression in the liver of the IUGR pigs. Conclusion: In conclusion, the lipid metabolism was abnormal in IUGR pigs, but the IUGR pigs consuming twice the normal level of choline had improved circulating lipid parameters, which could be related to the decreased activity of nicotinamide adenine dinucleotide phosphate-generating enzymes or the altered expressions of lipid metabolism-related genes.

• Journal of Distribution Science
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• v.12 no.4
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• pp.31-39
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• 2014

Purpose - This study investigates the following two issues. First, we attempt to find the important determinants of housing investment and to identify their significance rank using survey panel data. Recently, the expansion of global uncertainty in the real estate market has directly and indirectly influenced the Korean housing market; households demonstrate a sensitive reaction to changes in that market. Therefore, this study aims to draw conclusions from understanding how the impact of financial strength of the household is related to house investment. Second, we attempt to verify the effectiveness of diverse indices of financial strength such as DTI, LTV, and PIR as measures to monitor the housing market. In the continuous housing market recession after the global crisis, the government places top priority on residence stability. However, the government still imposes forceful restraints on indices of financial strength. We believe this study verifies the utility of these regulations when used in the housing market. Research design, data, and methodology - The data source for this study is the "National Survey of Tax and Benefit" from 2007 (1st) to 2011 (5th) by the Korea Institute of Public Finance. Based on this survey data, we use panel data of 3,838 households that have been surveyed continuously for 5 years. We sort the base variables according to relevance of house investment criteria using the decision tree model (DTM), which is the standard decision-making model for data-mining techniques. The DTM method is known as a powerful methodology to identify contributory variables for predictive power. In addition, we analyze how important explanatory variables and the financial strength index of households affect housing investment with the binary logistic multi-regressive model. Based on the analyses, we conclude that the financial strength index has a significant role in house investment demand. Results - The results of this research are as follows: 1) The determinants of housing investment are age, consumption expenditures, income, total assets, rent deposit, housing price, habits satisfaction, housing scale, number of household members, and debt related to housing. 2) The impact power of these determinants has changed more or less annually due to economic situations and housing market conditions. The level of consumption expenditure and income are the main determinants before 2009; however, the determinants of housing investment changed to indices of the financial strength of households, i.e., DTI, LTV, and PIR, after 2009. 3) Most of all, since 2009, housing loans has been a more important variable than the level of consumption in making housing market decisions. Conclusions - The results of this research show that sound financing of households has a stronger effect on housing investment than reduced consumption expenditures. At the same time, the key indices that must be monitored by the government under economic emergency conditions differ from those requiring monitoring under normal market conditions; therefore, political indices to encourage and promote the housing market must be divided based on market conditions.

• Journal of Digital Convergence
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• v.10 no.10
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• pp.215-220
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• 2012

This paper proposes a ontology of tree structure approach for adaptive object recognition in a situation-variant environment. In this paper, we introduce a new concept, ontology of tree structure ontology, for context sensitivity, as we found that many developed systems work in a context-invariant environment. Due to the effects of illumination on a supreme obstinate designing context-sensitive recognition system, we have focused on designing such a context-variant system using ontology of tree structure. Ontology can be defined as an explicit specification of conceptualization of a domain typically captured in an abstract model of how people think about things in the domain. People produce ontologies to understand and explain underlying principles and environmental factors. In this research, we have proposed context ontology, context modeling, context adaptation, and context categorization to design ontology of tree structure based on illumination criteria. After selecting the proper light-ontology domain, we benefit from selecting a set of actions that produces better performance on that domain. We have carried out extensive experiments on these concepts in the area of object recognition in a dynamic changing environment, and we have achieved enormous success, which will enable us to proceed on our basic concepts.

• Journal of IKEEE
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• v.13 no.4
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• pp.63-68
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• 2009

The power management integrated circuit(PMIC) for CCD image sensor is presented in this study. A CCD image sensor is very sensitive against temperature. The temperature, that is heat, is generally generated by the PMIC with low efficiency. Since the generated heat influences performance of CCD image sensor, it should be minimized by using a PMIC which has a high efficiency. In order to develop the PMIC with high efficiency, the input stage is designed with synchronous type step down DC-DC converter. The operating range of the converter is from 5V to 15V and the converter is controlled using PWM method. The PWM control circuit consists of a saw-tooth generator, a band-gap reference circuit, an error amplifier and a comparator circuit. The saw-tooth generator is designed with 1.2MHz oscillation frequency. The comparator is designed with the two stages OP Amp. And the error amplifier has 40dB DC gain and $77^{\circ}$ phase margin. The output of the step down converter is connected to input stage of the charge pump. The output of the charge pump is connected to input of the LDO which is the output stage of the PMIC. Finally, the PMIC, based on the PWM control circuit and the charge pump and the LDO, has output voltage of 15V, -7.5V, 3.3V and 5V. The PMIC is designed with a 0.35um process.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.2
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• pp.142-148
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• 2013

Bacterial diseases in soybean are bacterial pustule by Xanthomonas axonopodis pv. glycines, wildfire by Pseudomonas syringae pv. tabaci, bacterial blight by Pseudomonas savastanoi pv. glycines and bacterial brown spot by Pseudomonas syringae pv. syringae in Korea. It is difficult to identify each disease by early symptoms in fields, because the initial symptoms of these diseases are very similar to each other. In this study, we developed multiplex PCR detection method for rapid and accurate diagnosis of bacterial diseases. The glycinecin A of X. axonopodis pv. glycines, the tabtoxin of P. syringae pv. tabaci, the coronatine of P. savastanoi pv. glycines and the syringopeptin of P. syringae pv. syringae have been reported previously. These bacteriocin or phytotoxin producing genes were targeted to design the specific diagnostic primers. The primer pairs for diagnosis of each bacterial diseases were selected without nonspecific reactions. The studies on simultaneous diagnosis method were also conducted with primarily selected 21 primers. As a result, we selected PCR primer sets for multiplex PCR. Sizes of the amplified PCR products using the multiplex PCR primer set consist of 280, 355, 563 and 815 bp, respectively. This multiplex PCR method provides a efficient, sensitive and rapid tool for the diagnosis of the bacterial diseases in soybean.

• KIPS Transactions on Computer and Communication Systems
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• v.6 no.11
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• pp.437-444
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• 2017

Electric Pole is a supporting beam used for power transmission/distribution which is sensitive to external force change of environmental factors. Therefore, power facilities have many difficulties in terms of maintenance/conservation from external environmental changes and natural disasters that cause a great economic impact. The aerial wire cause elasticity due to the influence of temperature, or factors such as wind speed and wind direction, that weakens the electric pole. The situation may lead to many safety risk in day-to-day life. But, the safety assessment of the pole is carried out at the design stage, and aftermath is not considered. For the safety and maintenance purposes, it is very important to analyze the influence of weather factors on external forces periodically. In this paper, we analyze the acceleration data of the sensor nodes installed in electric pole for maintenance/safety purpose and use Kalman filter as noise compensation method. Fast Fourier Transform (FFT) is performed to analyze the influence of each meteorological factor, along with the meteorological factors on frequency components. The result of the analysis shows that the temperature, humidity, solar radiation, hour of daylight, air pressure, wind direction and wind speed were influential factors. In this paper, the influences of meteorological factors on frequency components are different, and it is thought that it can be an important factor in achieving the purpose of safety and maintenance.

• Journal of Distribution Science
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• v.14 no.2
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• pp.123-133
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• 2016

Purpose - Understanding how service convenience drives shopping performance is imperative for retailers such as department and large discount stores. Retailers have to enhance shopping productivity by reducing the costs of shopping, as convenience triggers customers' perceived shopping value, leading to customer satisfaction, and ultimately patronage behavior. Consumers, generally considering time as a scarce resource, are more sensitive to the time costs of tasks in regard to shopping trip, differently from forming perceptions of convenience in time orientation. Therefore, this study attempts to examine the moderating effects of consumers' time orientation on the relationships among service convenience of retailers and shopping performances such as shopping value and service performances. Research design, data, and methodology - The department and discount store chains were chosen as the point of analysis in this study. Data were collected from a survey of real-life consumers and all respondents were screened to ensure only those who had visited in the department and discount store chains within past six month prior to the day of data collection. Out of 600 self-reported surveys that were distributed, a total of 530 responses were returned and after excluding 20 incomplete responses, the final sample size was 510. The three hypotheses were proposed and tested in this study. The one hypothesis was on the moderating effects of time orientation for the effects of service convenience on shopping value (hedonic and utilitarian shopping value). The other two hypotheses were on the comparisons between high and low time-oriented customers with the effects in shopping value from service performance. Hierarchical moderated regression analysis was used to test the hypotheses. Results - The results suggest that the effect of service convenience on utilitarian shopping value and the positive effect of utilitarian shopping value on customer satisfaction are greater in low time orientation than high time orientation customers. Conversely, when customers are highly oriented toward time, the effects of hedonic shopping value on customer satisfaction and revisit intention are greater than for customers who are lowly oriented toward time. Conclusions - This study has two-fold significance. First, this study contributes to the consumer behavior and services marketing literature by incorporating customers' time orientation into the service convenience-shopping performance. Although the effect of service convenience on shopping performance might differ from customers' perceptions concerning shopping, there has been little investigation or comparison between customers' perception on time. This study is a first attempt to consider how the effects of service convenience on shopping value and service performance vary with differing levels of customers' time orientation. This study advances prior studies by showing that the service convenience-shopping value and service convenience-service performance relationships vary across different combinations of the customer's time orientation. The findings of this study suggest that the retailers need to enhance the experiential aspects of the stores for their high time-oriented customers. Conversely, for the low time-oriented customers, the retailers should boost the visual distinctiveness and ease of store navigation.

• Korean Journal of Human Ecology
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• v.19 no.1
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• pp.203-214
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• 2010

This study will examine the current condition of outdoor play in child care centers and the overall perception of teachers on outdoor play in regards to its related programs and children's reaction to them. Through examining such issues, this study will provide the basic data that can be applied in planning appropriate outdoor play activities, programs and environments. For the study, we surveyed teachers and directors of child care centers using a structured questionnaire. The objects of the survey were 22 child care centers in Daejeon and Seoul, who agreed to conduct the survey. The survey was conducted from August 1 to September 30 2006; 220 copies were distributed, and 188 copies were collected. The results of the study can be summarized as follows: 1) The number of outdoor plays per week were on average 1~2 in most cases, although teachers believed the play should be done everyday. Outdoor play time was mostly 21~30 minutes, while teachers thought 31~40 minutes as appropriate. Children's reaction scored the highest when they played outdoors for 30 minutes every day with their teachers involved in the play. As a result, we have concluded that the appropriate outdoor play should be conducted everyday for 30~40 minutes. 2) Outdoor play was mostly conducted as part of the overall educational plan rather than a separate plan. Since outdoor play affects children's development as much as indoor play, there is a need for development of a specific and separate plan for various outdoor play programs. 3) The outdoor play program that was most often conducted was equipment play and sand play. This indicated the monolithic nature of the outdoor program. Given the fact that children enjoy outdoor plays a lot (M=4.71), various programs including adventure play, sensitive play, and carpenter play should be developed. 4) In outdoor play, the teacher's role included supervising and interacting with children. According to the survey, teachers had a good understanding of the importance on safety and supervising issues in outdoor plays. However they seemed to overlook the importance of having better programs and improving teacher's participation to the play. Despite the importance of outdoor play to children's development, the result shows that teachers have tendencies to limit and obstruct outdoor plays by emphasizing supervising and safety issues instead. 5) Children's safety should not be the only consideration for outdoor plays; teachers ought to better understand that children's development can be maximized by the play. Furthermore, there should be emphasis placed on the program development and teacher's participation; teacher's participation should actively encourage the interactions between a child and a teacher, as well as among children.