• Korean Journal of Optics and Photonics
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• v.24 no.4
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• pp.176-183
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• 2013

In this paper, we report the design, fabrication and characterization of the 3-Dimensional optical receiver for a Laser Detection And Ranging (LADAR) system. The optical receiver is composed of three parts; $16{\pm}16$ Geiger Mode InGaAs Avalanche Photodiode (APD) array device operated at 1560 nm wavelength, Read Out Integrated Circuit (ROIC) measuring the Time-Of-Flight (TOF) of the return signal reflected from target objects, a package and cooler maintaining the proper operational condition of the detector and control electronics. We can confirm that the LADAR system can detect the signal from a target up to 1.2 km away, and it showed low Dark Count Rate (DCR) of less than 140 kHz, and higher than 28%-Photon Detection Efficiency (PDE). This is considered to be the best performance of the $16{\pm}16$ FPA APD optical receiver for a LADAR system.

• Journal of Aquaculture
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• v.18 no.2
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• pp.98-106
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• 2005

A feeding trial of two extruded pellets (EPI, 45% crude protein with 7% crude lipid and EP2, 47% crude protein with 10% crude lipid)${\times}$ two satiation rates (satiation and 80% satiation)${\times}$ three feeding frequencies (three, two and one meal a day) factorial design with three replications was carried out to investigate the optimum feeding frequency and satiation rate for growth of juvenile flounder. Flounder averaging 55 g were fed a extruded pellets for 58 days. Daily feed intake was affected by dietary composition, feeding frequency and satiation rate (P<0.05). Weight gain of fish fed the EP1 and EP2 was not affected by both dietary composition and feeding frequency (P>0.05), but affected by feeding satiation rate (P<0.05). Weight gain of fish fed the each of EP1 and EP2 twice daily with satiation was the highest among treatments, but was not significantly different to that of fish fed the diets three times daily with satiation feeding. Feed efficiency and protein efficiency ratio of the fish were not affected by dietary composition, feeding frequency and satiation rate (P>0.05). Moisture, crude protein and crude lipid contents of the muscle of fish were affected by satiation rate. Moisture and crude protein contents of the liver were affected by dietary composition. Based on fish performance results, it can be concluded that the proper feeding frequency for the growth of juvenile flounder grown from 55 g to 90 g is two meals a day with satiation feeding, regardless of dietary composition used in this study.

• Korea Journal of Hospital Management
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• v.7 no.4
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• pp.172-192
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• 2002

The purpose of this study is to ascertain whether the effect of introduction of OCS(Order Communication System) to the hospital is satisfied or not comparing the anticipated effect with the actual effect. For this purpose, a domestic hospital which has introduced and has been operating OCS for several years was chosen. Based on the internal data of S Hospital prepared before introducing OCS, researcher has analyzed the basic direction, design standard and status of operation after the introduction of OCS, etc. After analyzing the status of operations of several departments using OCS and interviewing with the chiefs of pertinent departments, a survey form was designed. Actual survey and interviews were conducted by the researcher for weeks to know whether doctors, nurses, medical technicians and clerks of the patient management dept. were satisfied with OCS and to find if they have any recommendations to improve OCS. Based on the analysis of survey, the effect of OCS was evaluated whether it has satisfied the anticipated effectiveness. For the question if they feel convenient in using OCS, doctors, nursing staffs in charge of ward and the staffs of billing dept. has answered that they were all satisfied(100%). The answers for the same question were relatively high in the case of nurses in charge of outpatient and staffs of radiography. Of course, there have been some nurses and staffs who complained for the inconvenience. However, overall satisfaction was high on the average. Some common problems occurred after the introduction of OCS were frequent errors due to instability of OCS system, paralysis of function of hardware on data back-up system and redundant investment due to erroneous choice of DB program in setting DB. It was also pointed out that lack of computer education and low participation of medical staffs has resulted in failure of developing effective software. As a result, it has lowered the efficiency of OCS. For example, some works have to be done by hands even after OCS. Based on the result of this research, recommendations to maximize the effect of OCS were presented as follows. First, strong leadership of CEO and active cooperation of doctors are mandatory. Second, all the process of hospital work should be analyzed and be redesigned in more efficient ways. Third, OCS should be designed to be user-based system which can be used efficiently by all staffs of the hospital. Forth, prior to the operation of OCS, proper tests of the program and trainings of the pertinent staff are required. Fifth, prior to the selection of hardware, BMT(Bench Marking Test) should be conducted. Sixth, before introducing OCS, staffs in charge of OCS should visit many hospitals operating the OCS system and take their cases into account.

• Research in Community and Public Health Nursing
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• v.11 no.2
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• pp.441-452
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• 2000

The purpose of this study was to identify the prevalence of urinary incontinence and its relating factors elderly communities. Subjects of this survey consisted of 877 elderly women and men in one Kun. Korea, who were over 60 years old. The design for this study was descriptive: the subjects were interviewed by well trained investigators from July 9. 1999 to July 20. 1999. During that survey period, the subjects were interviewed with a structured questionnaire. The data were analyzed by frequency, percentage, $X^2-test$. T-test using an SAS program. The results of the study were the following: 1. The prevalence rate of urinary incontinence was 20.1 %. of the total. The types of urinary incontinence were mixed incontinence 44.3%. stress incontinence 38.1%. and urge type incontinence 17.6%. 2. The relating factors of urinary incontinence were as follows: 1) 33.5% of UI(urinary incontinence) subjects reported urine loss once a month. twice or three times a week 23.3%. one or two times a day 17.0% 2) 38.1% of elderly reported only 1 to 2 drops. 1 t-spoon 36.9%. 1 T-spoon 15.9% 3) The volume of urine loss registered by changing underwear was 63.1 %. no necessity of changing underwear was 22.1 %. or using some type of pads was 13.1%. 4) 62.5% of UI subjects never discussed their UI problem with other people. 73.9% of the total had never experienced any treatment for their UI problem. The reasons for not receiving medical cure were their typical conception about urinary incontinence taking UI as a normal part of aging 76.2% and due to their bad financial situation 9.2%. 3. Women had more prevalence of UI than men (p=0.01), and it was found that the worse the subjective health state. the higher the prevalence of UI (p=0.001). However. there was no statistical difference in daily frequency of UI (p>0.05). The more nocturnal incontinence (p=0.001), the more intermittent stream experience (p = 0.01), the more retention experience (p = 0.01), and the more incomplete the emptying experience (p=0.001), the higher the prevalence of UI. 4. UI groups had lower ADL scores than non UI groups(p=0.01). The level of depression in the group of urinary incontinence was significantly higher than that of non incontinence group (p=0.0001). As shown above, the elderly people suffering from UI haven't been treated properly: their subjective health state and their ADL competence was lower, and their depression level was higher than non UI groups. Therefore, the development of a proper urinary incontinence management program are required so that they can lead more healthy lives. Also continual case studies for the elderly people with UI are necessary.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.10C
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• pp.1015-1026
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• 2002

As per increasing research interest in the field of collaborative computing in recent year, the importance of security issues on that area is also incrementally growing. Generally, the persistency of collaborative system is facilitated with conventional authentication and cryptography schemes. It is however, hard to meet the access control requirements of distributed collaborative computing environments by means of merely apply the existing access control mechanisms. The distributed collaborative system must consider the network openness, and various type of subjects and objects while, the existing access control schemes consider only some of the access control elements such as identity, rule, and role. However, this may cause the state of security level alteration phenomenon. In order to handle proper access control in collaborative system, various types of access control elements such as identity, role, group, degree of security, degree of integrity, and permission should be taken into account. Futhermore, if we simply define all the necessary access control elements to implement access control algorithm, then collaborative system consequently should consider too many available objects which in consequence, may lead drastic degradation of system performance. In order to improve the state problems, we propose a novel access control framework that is suitable for the distributed collaborative computing environments. The proposed scheme defines several different types of object elements for the accessed objects and subjects, and use them to implement access control which allows us to guarantee more solid access control. Futhermore, the objects are distinguished by three categories based on the characteristics of the object elements, and the proposed algorithm is implemented by the classified objects which lead to improve the systems' performance. Also, the proposed method can support scalability compared to the conventional one. Our simulation study shows that the performance results are almost similar to the two cases; one for the collaborative system has the proposed access control scheme, and the other for it has not.

• Journal of the Microelectronics and Packaging Society
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• v.19 no.2
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• pp.7-15
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• 2012

Semiconductor packages are increasingly moving toward miniaturization, lighter and multi-functions for mobile application, which requires highly integrated multi-stack package. To meet the industrial demand, the package and silicon chip become thinner, and ultra-thin packages will show serious reliability problems such as warpage, crack and other failures. These problems are mainly caused by the mismatch of various package materials and geometric dimensions. In this study we perform the numerical analysis of the warpage deformation and thermal stress of 4-layer stacked FBGA package after EMC molding and reflow process, respectively. After EMC molding and reflow process, the package exhibits the different warpage characteristics due to the temperature-dependent material properties. Key material properties which affect the warpage of package are investigated such as the elastic moduli and CTEs of EMC and PCB. It is found that CTE of EMC material is the dominant factor which controls the warpage. The results of RSM optimization of the material properties demonstrate that warpage can be reduced by $28{\mu}m$. As the silicon die becomes thinner, the maximum stress of each die is increased. In particular, the stress of the top die is substantially increased at the outer edge of the die. This stress concentration will lead to the failure of the package. Therefore, proper selection of package material and structural design are essential for the ultra-thin die packages.

• Journal of Intelligence and Information Systems
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• v.16 no.1
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• pp.17-43
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• 2010

This research considers the role of knowledge as marketing message, designs and analyses the personal experience management (PEM) business model using Human-Reader system. It is difficult to save and manage person's daily experience and relevant contents due to the lack of proper infrastructure and system. On the contrary, using Human-Reader infrastructure, person's experience and various relevant contents can be easily saved and managed because seamlessness between offline and online and the various devices that person can always carry along in ubiquitous environment. Since person can store and manage information, contents and advertisements through Human-Reader system and u-PEMS, marketing messages and advertisements do not have to be repetitive and stimulating. Instead, marketing messages and advertisements in Human-Reader environment should be granting values that can be saved and managed. We propose various scenarios, processes and its issues. And we analyze the expected value of RFID tag used on the proposed business model by so-called 'Tag Evaluation Model' and assess the assumptions that are basis of the proposed business model for evaluate the feasibility of the u-PEM business model.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.30 no.5
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• pp.895-907
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• 2020

With the recent increasing influence of multimedia content other than the text-based content, services that help to process information in content brings us great convenience. These services' representative features are searching and masking the sensitive data. It is not difficult to find the solutions that provide searching and masking function for text information and image. However, even though we recognize the necessity of the technology for searching and masking a part of the audio data, it is not easy to find the solution because of the difficulty of the technology. In this study, we propose web application that provides searching and masking functions for audio data using audio partitioning method. While we are achieving the research goal, we evaluated several speech to text conversion APIs to choose a proper API for our purpose and developed regular expressions for searching sensitive information. Lastly we evaluated the accuracy of the developed searching and masking feature. The contribution of this work is in design and implementation of searching and masking a sensitive information from the audio data by the various functionality proving experiments.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.782-785
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• 2011

Needs for MG(Microgrid) development are increasing all over the world as a solution to the problems including the depletion problem of energy resources, the growing demand for electric power and the climatic and environmental change. Especially Photovoltaic power is one of the most general renewable energy resources. However there is a problem of the uniformity of power quality because the power generated from solar light is very sensitive to climate fluctuation (variation of insolation and duration of sunshine, etc). As a solution to the above problem, ESS(Energy Storage System) is considered generally, but it has some limitations. To solve this problem this paper suggests a hybrid estimation method of photovoltaic power generation according to two climatic factors, i.e. insolation and sunshine. This result seems to help design the appropriate capacity of ESS and estimate the proper switching time between DC and AC power in the premises power system and thus maintain the uniformity of power quality.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.1
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• pp.441-452
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• 2016

The purpose of this study was to examine the characteristics of domestic research into breast-feeding intervention education geared toward mothers and the content of the intervention based on the existing literature in an effort to provide information on how to offer the best intervention. Domestic studies reported between January 1993 and December 2014 were analyzed using four different databases. Fifteen studies were selected from 76 studies included in the databases after performing the searches. How long breast-feeding intervention remains effective should be studied to secure scientific rationales, which is one of the proper nursing interventions to boost breast feeding. As a result of analyzing the papers according to Whittmore and Knaf's integrative review method, the individual educational intervention was offered in two papers, and the individual education and group education were both provided in four. In nine papers, individual education, group education, phone counseling and education by home visits were all offered. Follow-up studies should be conducted by adopting a systematic research design to find more scientific evidence for appropriate nursing interventions to boost breast-feeding. These results will be useful for the development of educational programs for breast-feeding if more accurate information on breast-feeding education for mothers can be obtained.