• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.31 no.12C
• /
• pp.1173-1183
• /
• 2006

In this paper, we propose an efficient method for improving visual quality of AR-FGS (Adaptive Reference FGS) which is adopted as a key scheme for SVC (Scalable Video Coding) or H.264 scalable extension. The standard FGS (Fine Granularity Scalability) adopts AR-FGS that introduces temporal prediction into FGS layer by using a high quality reference signal which is constructed by the weighted average between the base layer reconstructed imageand enhancement reference to improve the coding efficiency in the FGS layer. However, when the enhancement stream is truncated at certain bitstream position in transmission, the rest of the data of the FGS layer will not be available at the FGS decoder. Thus the most noticeable problem of using the enhancement layer in prediction is the degraded visual quality caused by drifting because of the mismatch between the reference frame used by the FGS encoder and that by the decoder. To solve this problem, we exploit the principle of cyclical block coding that is used to encode quantized transform coefficients in a cyclical manner in the FGS layer. Encoding block coefficients in a cyclical manner places 'higher-value' bits earlier in the bitstream. The quantized transform coefficients included in the ealry coding cycle of cyclical block coding have higher probability to be correctly received and decoded than the others included in the later cycle of the cyclical block coding. Therefore, we can minimize visual quality degradation caused by bitstream truncation by adjusting weighting factor to control the contribution of the bitstream produced in each coding cycle of cyclical block coding when constructing the enhancement layer reference frame. It is shown by simulations that the improved AR-FGS scheme outperforms the standard AR-FGS by about 1 dB in maximum in the reconstructed visual quality.

• Journal of Hospice and Palliative Care
• /
• v.5 no.2
• /
• pp.94-100
• /
• 2002

Purpose : The system to refer terminally ill patients to palliative or hospice care which ultimately give them emotional, psychological, and social support hasn't been fully developed and organized yet in Korea. The controversies concerning the current referral system are being analyzed to present the improvements. Methods : The questionnaires were asked to be filled out by family members of the 76 patients by phone interview, who were referred from the Seoul National University Hospital between April, 2001 to March, 2002. They were referred to the 35 palliative and hospice care-giving institutes and hospitals which were given questionnaires by mail. Results : Of the 76 patient's family members, 47 family members accepted to answer the questionnaire. The first thing that influence to family to determine the referral of patient was solicitation of doctors or nurses (44%). And they were influenced by allowance for the other things such as convenience of patients (32%), convenience of caring family members (24%). In the course of determining of referred institutes, responders had considered at first their dwelling area, and then fame of institutes, the place which patent had wanted to spend last hours or which is suitable for patient's funeral service, and their financial condition. Thirty-eight the 47 responders answered that they had experienced difficulties in referral procedure. The worst among difficulties was unwanted discharge, and followings were lack of information about the referred institutes, concern about patient's suffering, resistance of patient and opposition of other family members, etc. Although they expressed dissatisfaction in referral procedure, most of them answered they had been satisfied with hospice care at referred institute after referral. Merits of referral which responders counted were patient's peace, caring family's comfort and reduced cost in order. Of the 35 referred institutes, 24 institutes' staffs responded mail questionnaires and sent to us in return. Except one responder, the rest approved the referral system and thought that referred patients had been satisfied with their hospice care. And they claimed that systemic support of the government is definitely necessary. The most difficult thing which responders experienced in care of referred patients was lack of information about patients. Besides, there were patient's financial problems, lack of understanding about their institutes of patients or family, and inconvenience of terminal cancer patient's pain control. Conclusion : The development and support of the organized referral system is needed to alleviate the troubles which patients, family members, and palliative or hospice institutes and hospitals have to face through the procedure of the referral.

• Journal of Broadcast Engineering
• /
• v.22 no.2
• /
• pp.193-206
• /
• 2017

In this paper, we propose a rate control method based on the $R-{\lambda}$ model that supports a parallel encoding structure in GOP levels or IDR period levels for 4K UHD input video in real-time. For this, a slice-level bit allocation method is proposed for parallel encoding instead of sequential encoding. When a rate control algorithm is applied in the GOP level or IDR period level parallelism, the information of how many bits are consumed cannot be shared among the frames belonging to a same frame level except the lowest frame level of the hierarchical B structure. Therefore, it is impossible to manage the bit budget with the existing bit allocation method. In order to solve this problem, we improve the bit allocation procedure of the conventional ones that allocate target bits sequentially according to the encoding order. That is, the proposed bit allocation strategy is to assign the target bits in GOPs first, then to distribute the assigned target bits from the lowest depth level to the highest depth level of the HEVC hierarchical B structure within each GOP. In addition, we proposed a processing method that is used to improve subjective image qualities by allocating the bits according to the coding complexities of the frames. Experimental results show that the proposed bit allocation method works well for frame-level parallel HEVC software encoders and it is confirmed that the performance of our rate controller can be improved with a more elaborate bit allocation strategy by using the preprocessing results.

• Applied Microscopy
• /
• v.35 no.3
• /
• pp.135-152
• /
• 2005

Prefrontal cortex is a psychological and metaphysical cortex, which deals with feeling, memory, planning, attention, personality, etc. And it also integrates above-mentioned events with motor control and locomotor activities. Prefrontal cortex works as a highest CNS center, since the above mentioned functions are very important for one's successful life, and further more they are upgraded every moments through memory and learning. Many of these highest functions are supposed to be generated via forebrain basal nuclei (caudate nucleus, fundus striati nucleus, accumbens septi nucleus, septal nucleus, etc.). In this experiment, prefrontal efferent terminals within basal forebrain nuclei were ultrastructurally studied. Spraque Dawley rats, weighing $250{\sim}300g$ each, were anesthetized and their heads were fixed on the stereotaxic apparatus (experimental model, David Kopf Co.). Rats were incised their scalp, perforated a 3mm-wide hole on the right side of skull at the 11mm anterior point from the frontal O point (Ref. 13, Fig. 1), suctioned out the prefrontal cortex including cortex of the frontal pole, with suction instrument. Two days following the operations, small tissue blocks of basal forebrain nuclei were punched out, fixed in 1% glutaraldehyde-1% paraformaldehyde solution followed by 2% osmium tetroxide solutions. Ultrathin sections were stained with 1% borax-toluidin blue solution, and the stained sections were obserbed with an electron microscope. Degenerating axon terminals were found within all the basal forbrain nuclei. Numbers of degenerated terminals were largest in the caudate nucleus, next in order, in the fundus striati nucleus, in the accumbens septi nucleus, and the least in the septal nucleus. Only axospinous terminals were degenerated within the caudate nucleus and the fundus striati nucleus, and they showed the characters of striatal motor control system. Axodendritic and axospinous terminals were degenerated within the accumbens septi nucleus and the lateral septal nucleus, and they showed the characters of visceral limbic system. Prefrontal role in integrating the limbic system with the striatal system, en route basal forebrain nuclei, was discussed.

• Journal of The Korean Association For Science Education
• /
• v.33 no.7
• /
• pp.1431-1449
• /
• 2013

This study is based on the assertion that science museums should consider visitors' views and expectations as they are not satisfied in many cases. In this study, we investigated 31 scientifically gifted students and 177 science high school students about their image of science museums. Using the questionnaire, it was found that only 51% of students visited science museums; however, the average number of visits was 4.2. This means that students tended to re-visit after the first visit of the science museum. Students had a 'good' image of science museums when they incurred hands-on experiences and observed new, interesting, curious and funny exhibits. And students had a 'bad' image of science museums due to the following aspects: lack of new and interesting exhibits, information and guide, diverse contents, and hands-on experience; deficiencies in environment; and inadequacy of the management, operation and composition of exhibits. Therefore, they hoped that science museums will provide more hands-on experiences and experiments, new and interesting exhibits, systematic management and composition of exhibits, information and guides, and a good environment. So science museums need to pay special attention to aspects like management, information guides and environment for the first-time visitors. Based on the above results, we suggested "Directions for a good science museum based on students' views". While asking students what topics they wanted to know and learn in a science museum, each student was given the choice of four topics; eventually, 2.9 answers overlapped for each topic. When classifying students' topics into four main themes for the Gwangju National Science Museum, the order from the most popular theme to the least one was 'science in everyday life', 'ocean/space/future science', 'light and science', and 'culture, art and science'. Among the topics mentioned by students, only 37% are exhibited in Seoul, Gwacheon, Daejeon, or Gwangju science museums. We hope that the results and research methods will be used for evaluation, re-construction, and reinvigorated presentation of science museums.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.44 no.11
• /
• pp.1666-1671
• /
• 2015

The purpose of this study was to provide trustworthy nutritional information by analyzing sugar contents of commercial retort foods. A total of 70 retort food samples were collected, which included curry (n=21), blackbean- sauce (n=16), sauce (n=17), and meat (n=16) from markets in Seoul and Gyeonggi-do. Contents of sugars such as glucose, fructose, sucrose, maltose, and lactose were analyzed in retort foods by using a high performance liquid chromatography-refractive index detector and compared to their assigned values on nutritional information labels. Analyzed sugar contents of curries, black-bean-sauces, sauces, and meats ranged from 1.05~4.63 g/100 g, 1.76~5.16 g/100 g, 0.35~25.44 g/100 g, and 1.98~11.07 g/100 g, respectively. Sauces were found to contain the highest amounts of total sugar. These analysis values were equivalent to the reference values indicated on nutrition labels, which were 40~119.5% for curries, 29~118% for black-bean-sauces, 18~118% for sauces, and 70~119.8% for meats. Therefore, this study provides reliable analytical values for sugar contents in retort foods.

• Journal of Intelligence and Information Systems
• /
• v.19 no.3
• /
• pp.45-55
• /
• 2013

Thereby using smartphone and mobile device be more popular the more people utilize mobile device in many area such as education, news, financial. In January, 2007 Apple release i-phone it touch off rapid increasing in user of smartphone and it create new market and these broaden its utilization area. Smartphone use WiFi or 3G mobile radio communication network and it has a feature that can access to internet whenever and anywhere. Also using smartphone application people can search arrival time of public transportation in real time and application is used in mobile banking and stock trading. Computer's function is replaced by smartphone so it involves important user's information such as financial and personal pictures, videos. Present smartphone security systems are not only too simple but the unlocking methods are spreading out covertly. I-phone is secured by using combination of number and character but USA's IT magazine Engadget reveal that it is easily unlocked by using combination with some part of number pad and buttons Android operation system is using pattern system and it is known as using 9 point dot so user can utilize various variable but according to Jonathan smith professor of University of Pennsylvania Android security system is easily unlocked by tracing fingerprint which remains on the smartphone screen. So both of Android and I-phone OS are vulnerable at security threat. Compared with problem of password and pattern finger recognition has advantage in security and possibility of loss. The reason why current using finger recognition smart phone, and device are not so popular is that there are many problem: not providing reasonable price, breaching human rights. In addition, finger recognition sensor is not providing reasonable price to customers but through continuous development of the smartphone and device, it will be more miniaturized and its price will fall. So once utilization of finger recognition is actively used in smartphone and if its utilization area broaden to financial transaction. Utilization of biometrics in smart device will be debated briskly. So in this thesis we will propose fingerprint numbering system which is combined fingerprint and password to fortify existing fingerprint recognition. Consisted by 4 number of password has this kind of problem so we will replace existing 4number password and pattern system and consolidate with fingerprint recognition and password reinforce security. In original fingerprint recognition system there is only 10 numbers of cases but if numbering to fingerprint we can consist of a password as a new method. Using proposed method user enter fingerprint as invested number to the finger. So attacker will have difficulty to collect all kind of fingerprint to forge and infer user's password. After fingerprint numbering, system can use the method of recognization of entering several fingerprint at the same time or enter fingerprint in regular sequence. In this thesis we adapt entering fingerprint in regular sequence and if in this system allow duplication when entering fingerprint. In case of allowing duplication a number of possible combinations is $\sum_{I=1}^{10}\;{_{10}P_i}$ and its total cases of number is 9,864,100. So by this method user retain security the other hand attacker will have a number of difficulties to conjecture and it is needed to obtain user's fingerprint thus this system will enhance user's security. This system is method not accept only one fingerprint but accept multiple finger in regular sequence. In this thesis we introduce the method in the environment of smartphone by using multiple numbered fingerprint enter to authorize user. Present smartphone authorization using pattern and password and fingerprint are exposed to high risk so if proposed system overcome delay time when user enter their finger to recognition device and relate to other biometric method it will have more concrete security. The problem should be solved after this research is reducing fingerprint's numbering time and hardware development should be preceded. If in the future using fingerprint public certification becomes popular. The fingerprint recognition in the smartphone will become important security issue so this thesis will utilize to fortify fingerprint recognition research.

• Journal of KIISE:Databases
• /
• v.30 no.4
• /
• pp.381-396
• /
• 2003

Subsequence matching is an operation that finds subsequences whose changing patterns are similar to a given query sequence from time-series databases. This paper points out the performance bottleneck in subsequence matching, and then proposes an effective method that improves the performance of entire subsequence matching significantly by resolving the performance bottleneck. First, we analyze the disk access and CPU processing times required during the index searching and post processing steps through preliminary experiments. Based on their results, we show that the post processing step is the main performance bottleneck in subsequence matching, and them claim that its optimization is a crucial issue overlooked in previous approaches. In order to resolve the performance bottleneck, we propose a simple but quite effective method that processes the post processing step in the optimal way. By rearranging the order of candidate subsequences to be compared with a query sequence, our method completely eliminates the redundancy of disk accesses and CPU processing occurred in the post processing step. We formally prove that our method is optimal and also does not incur any false dismissal. We show the effectiveness of our method by extensive experiments. The results show that our method achieves significant speed-up in the post processing step 3.91 to 9.42 times when using a data set of real-world stock sequences and 4.97 to 5.61 times when using data sets of a large volume of synthetic sequences. Also, the results show that our method reduces the weight of the post processing step in entire subsequence matching from about 90% to less than 70%. This implies that our method successfully resolves th performance bottleneck in subsequence matching. As a result, our method provides excellent performance in entire subsequence matching. The experimental results reveal that it is 3.05 to 5.60 times faster when using a data set of real-world stock sequences and 3.68 to 4.21 times faster when using data sets of a large volume of synthetic sequences compared with the previous one.

• The KIPS Transactions:PartA
• /
• v.8A no.4
• /
• pp.469-478
• /
• 2001

In the virtual memory system, page replacement policy exerts a great influence on the performance of demand paging. There are LRU(Least Recently Used) and LFU (Least Frequently Used) as the typical replacement policies. The LRU policy performs effectively in many cases and adapts well to the changing workloads compared to other policies. It however cannot distinguish well between frequently and infrequently referenced pages. The LFU policy requires that the page with the smallest reference count be replaced. Though it considers all the references in the past, it cannot discriminate between references that occurred far back in the past and the more recent ones. Thus, it cannot adapt well to the changing workload. In this paper, we first analyze memory reference patterns of eight applications. The patterns show that the recently referenced pages or the frequently referenced pages are accessed continuously as the case may be. So it is rather hard to optimize page replacement scheme by using just one of the LRU or LFU policy. This paper makes an attempt to combine the advantages of the two policies and proposes a new page replacement policy. In the proposed policy, paging list is divided into two lists (LRU and LFU lists). By keeping the two lists in recency and reference frequency order respectively, we try to restrain the highly referenced pages in the past from being replaced by the LRU policy. Results from trace-driven simulations show that there exists points on the spectrum at which the proposed policy performs better than the previously known policies for the workloads we considered. Especially, we can see that our policy outperforms the existing ones in such applications that have reference patterns of re-accessing the frequently referenced pages in the past after some time.

• Korean Journal of Culture and Social Issue
• /
• v.17 no.1
• /
• pp.81-113
• /
• 2011

This study investigates leisure activity, involvement and self-concept in cyberspace of various age groups of adolescents. A total of 1,388 students (elementary school=337, middle school=326, high school=361, university=364, consisting of 696 male and 692 female) participated in the study. The results are as follows. First, although the vast majority of adolescents (96.9%) had a computer at home, majority of adolescents visited Internet cafe. Second, 70.3% of adolescents visited Internet cafe to play Internet games, followed by engaging in information search, chatting, and participated in cyber community. Third, on average adolescents spent 5.43 hours per week playing Internet games, with more males playing Internet games than female adolescents. As for information search, the weekly average was 2.60 hours, with university students spending more time than the other groups. As for chatting, the weekly average was 1.69 hours, with no significant differences among the groups. The weekly average of Internet use was 9.65 hours, with older groups spending more time. The weekly average use of computer was 10.91 hours, with older groups spending more time and more males using more computer than females. Fourth, as for self-concept in cyberspace, elementary and middle school students reported that they had fun, while high school and university students reported that they were the same as in the regular daily life. In addition, adolescents reported that they spent leisure activity in cyberspace and they become a fictional character in cyberspace. Fifth, when they played Internet games, regardless of age and gender, adolescents reported that they had fun, followed by that they were absorbed, that they became aggressive, and that they were the same as in the regular daily life. Sixth, when they chatted on Internet, regardless of age and gender, adolescents reported that they had fun, followed by that they were not interested, that they were the same as in the regular daily life, and that they do not chat on Internet. Seventh, when they interacted with their friends on Internet, regardless of age and gender, majority of adolescents reported that they had fun, followed by that they conversed, that they were the same as in the regular daily life, and that they felt closer. These results indicate that Korean adolescents view Internet as a place to spend their leisure time and that they enjoyed spending time on Internet.