• Journal of Intelligence and Information Systems
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• v.19 no.3
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• pp.45-55
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• 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 the Korean Society of Food Science and Nutrition
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• v.42 no.9
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• pp.1499-1512
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• 2013

The purpose of this study was to compare the coffee shop visits of Koreans and Mongolians, and to determine the quality attributes that should be managed by Importance-Performance Analysis (IPA). The survey was conducted in Seoul and the Gyeonggi Province of Korea, and at Ulaanbaatar in Mongolia from April to May 2012. The questionnaire was distributed to 380 Koreans and 380 Mongolians, with 253 and 250 responses from the Koreans and Mongolians, respectively, used for statistical analyses. From the results, Koreans visited coffee shops more frequently than Mongolians, with both groups mainly visiting a coffee shop with friends. Koreans also spent more time in a coffee shop than Mongolians. In addition, they generally used a coffee shop, regardless of time. In terms of coffee preference, Koreans preferred Americano and Mongolians preferred Espresso. The most frequently stated purpose of Koreans for visiting a coffee shop was to rest, while Mongolians typically visited to drink coffee. The general price range respondents spent on coffee was less than 4~8 thousand won for the Koreans and 2~4 thousand won for the Mongolians. Both Koreans and Mongolians obtained information about coffee shops from recommendations. According to the IPA results of 20 quality attributes of coffee shops, the selection attributes with high importance but low satisfaction were quality, price, and kindness for Koreans, but none of the attributes was found for Mongolians.

• Korean Journal of Remote Sensing
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• v.39 no.6_2
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• pp.1565-1576
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• 2023

An atmospheric correction algorithm based on the radiative transfer model is required to obtain remote-sensing reflectance (R_rs) from the Geostationary Ocean Color Imager-II (GOCI-II) observed at the top-of-atmosphere. This R_rs derived from the atmospheric correction is utilized to estimate various marine environmental parameters such as chlorophyll-a concentration, total suspended materials concentration, and absorption of dissolved organic matter. Therefore, an atmospheric correction is a fundamental algorithm as it significantly impacts the reliability of all other color products. However, in clear waters, for example, atmospheric path radiance exceeds more than ten times higher than the water-leaving radiance in the blue wavelengths. This implies atmospheric correction is a highly error-sensitive process with a 1% error in estimating atmospheric radiance in the atmospheric correction process can cause more than 10% errors. Therefore, the quality assessment of R_rs after the atmospheric correction is essential for ensuring reliable ocean environment analysis using ocean color satellite data. In this study, a Quality Assurance (QA) algorithm based on in-situ R_rs data, which has been archived into a database using Sea-viewing Wide Field-of-view Sensor (SeaWiFS) Bio-optical Archive and Storage System (SeaBASS), was applied and modified to consider the different spectral characteristics of GOCI-II. This method is officially employed in the National Oceanic and Atmospheric Administration (NOAA)'s ocean color satellite data processing system. It provides quality analysis scores for R_rs ranging from 0 to 1 and classifies the water types into 23 categories. When the QA algorithm is applied to the initial phase of GOCI-II data with less calibration, it shows the highest frequency at a relatively low score of 0.625. However, when the algorithm is applied to the improved GOCI-II atmospheric correction results with updated calibrations, it shows the highest frequency at a higher score of 0.875 compared to the previous results. The water types analysis using the QA algorithm indicated that parts of the East Sea, South Sea, and the Northwest Pacific Ocean are primarily characterized as relatively clear case-I waters, while the coastal areas of the Yellow Sea and the East China Sea are mainly classified as highly turbid case-II waters. We expect that the QA algorithm will support GOCI-II users in terms of not only statistically identifying R_rs resulted with significant errors but also more reliable calibration with quality assured data. The algorithm will be included in the level-2 flag data provided with GOCI-II atmospheric correction.

• Korean Journal of Environmental Agriculture
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• v.37 no.2
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• pp.73-78
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• 2018

BACKGROUND: Soil salinity of reclaimed tidal land in Korea is highly important factor. High salinity is harmful to crop productivity. Jerusalem artichoke (Helianthus tuberosus L.) is known to be salt-tolerant and has high adaptability to diverse pedo-climatic conditions. The objective of this study was to assess the changes of soil properties and crop productivity according to salt concentration in the reclaimed tidal lands. METHODS AND RESULTS: Experimental sites were selected at Saemangeum ($35^{\circ}46^{\prime}N$, $126^{\circ}37^{\prime}E$) reclaimed tidal land, and their dominant soil series were Munpo (coarse loamy, mixed, non-acid, mesic, typic Fluvaquents). H. tuberosus L were collected from 12 locations across Korea. Tubers were planted at $75{\times}25cm$ with EC 2 to $7dS\;m^{-1}$. Soil samples were periodically collected from both 0~20 cm and 20~40 cm depths of each site. Soil salinity and soil moisture contents were varied depending on weather conditions. Soil electrical conductivity varied from 1.0 to $5.9dS\;m^{-1}$, and soil moisture contents varied from 9.2 to 28.7%. The white-colored tubers of H. tuberosus L. collected from 'Yeongwol-gun' exhibited the highest height (207 cm), followed by the white-colored tubers of H. tuberosus L. collected from 'Iksan-si'(202 cm). The white-colored tubers of H. tuberosus L. collected from 'GyeongJu-si' showed the highest yield (549 kg/10a). The purple-colored tubers of H. tuberosus L. collected from 'Yeongwol-gun' showed the highest yield (615 kg/10a). CONCLUSION: Our results indicate that the plant height and tuber yield did not appear to be correlated. Considering yield and inulin content, the GyeongJu-si seemed to be suitable as the white-colored tubers of H. tuberosus L. and the Yeongwol-gun seemed to be suitable as the purple-colored tubers of H. tuberosus L. in the reclaimed tidal lands. However, it is necessary to consider the relationship between the inulin content and the yield.

• The Journal of Korean Philosophical History
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• no.56
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• pp.151-180
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• 2018

Since the completion of the theories on human ethics and moral had been established to pursue by Confucian thinkers like Confucius and Mencius, they generally had agreed to present the basic principles for human education which every human could be the sage. In these principles for human ethics and morality there is on the premise that the knowledge about your own ethical and that the completion of the so-called act(爲) and learning(學). They had given to us that how to get a goal for the ethical and moral lives there are several academic oriented methodology will have act and learning set. In the point of achieving complete figures which act and learning for good society, there was named the sage(聖). This concept sage has two major types. One is on for the political figures that completed, and the other one is for the realm of academic side. Confucian as above mentioned the moral human being is equipped with a complete personality and political ability to make man and society perfect. Confucius has been understood as a complete human being. Yes, ideal for these two types of figures will be fulfilled in some way? They take a mystical ability to a priori or a posteriori, such as human effort can reach the sage. There are many thinkers are obvious and logical answer for this major problem in the system of confucian philosophy I have been trying. About the sage(聖), inherently natural learning(生知) occur to the position sage or knowledge (學知), can lead to there are two of the doctrine for that problem. With the study of learning and knowledge on human beings and real society the two systems concerned together. In fact, the main content of the "Analects of Confucius" we have a set of ethical and moral values not the benevolent conversation about Jin(仁) and his disciples a steady emphasis but on in praise of learning (學) for. However, at the time in Han Tang(漢唐) Han Wi(韓愈) and Wang Chung(王充), according to such thinkers the sage is already a priori determined, cannot be reached by human effort. But At the beginning of the Neo-Confucianism, Cheng I(程?) for the pioneer this Song(宋) scholars, regarding this issue could rebirth the thought that every human could be the sage through the learning as the pre-Chin(先秦) times.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.15 no.2
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• pp.271-288
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• 2002

Authors investigated the pathogenesis and treatment of dennatosurgical diseases in the ImJeungJiNamUiAn(臨證指南醫案). 1. The symptoms and diseases of dermatosurgery were as follows; 1) BanSaJinRa(반사진라) : eczema, atopic dermatitis, seborrheic dermatitis, psoriasis, lichen planus, pityriasis rosea, hives, dermographism, angioedema, cholinergic urticaria, urticaria pigmentosa, acne, milium, syringoma, keratosis pilaris, discoid lupus erythematosus, hypersensitivity vasculitis, drug eruption, polymorphic light eruption, rheumatic fever, juvenile rheumatoid arthritis(Still's disease), acute febrile neutrophilic dermatosis(Sweet's syndrome), Paget's disease, folliculitis, viral exanthems, molluscum contagiosum, tinea, tinea versicolor, lymphoma, lymphadenitis, lymphangitis, granuloma annulare, cherry angioma 2) ChangYang(瘡瘍) : acute stage eczema, seborrheic dermatitis, stasis ulcer, intertrigo, xerosis, psoriasis, lichen planus, ichthyosis, pityriasis rosea, rosacea, acne, keratosis pilaris, dyshidrosis, dermatitis herpetiformis, herpes gestationis, bullae in diabetics, pemphigus, lupus erythematosus, fixed drug eruption, erythema multiforme, toxic epidermal necrolysis, toxic shock syndrome, staphylococcal scaled skin syndrome, scarlet fever, folliculitis, impetigo, pyoderma gangrenosum, tinea, candidiasis, scabies, herpes simplex, herpes zoster, chicken pox, Kawasaki syndrome, lipoma, goiter, thyroid nodule, thyroiditis, hyperthyroidism, thyroid cancer, benign breast disorder, breast carcinoma, hepatic abscess, appendicitis, hemorrhoid 3) Yeok(疫) : scarlet fever, chicken pox, measles, rubella, exanthem subitum, erythema infectiosum, Epstein-Barr virus infection, cytomegalovirus infection, hand-foot-mouth disease, Kawasaki disease 4) Han(汗) : hyperhidrosis 2. The pathogenesis and treatment of dermatosurgery were as follows; 1) When the pathogenesis of BalSa(발사), BalJin(發疹), BalLa(발라) and HangJong(項腫) are wind-warm(風溫), exogenous cold with endogenous heat(外寒內熱), wind-damp(風濕), the treatment of evaporation(解表) with Menthae Herba(薄荷), Arctii Fructus(牛蒡子), Forsythiae Fructus(連翹) Mori Cortex(桑白皮), Fritillariae Cirrhosae Bulbus(貝母), Armeniaoae Amarum Semen(杏仁), Ephedrae Herba(麻黃), Cinnamomi Ramulus(桂枝), Curcumae Longae Rhizoma(薑黃), etc can be applied. 2) When the pathogenesis of BuYang(부양), ChangI(瘡痍) and ChangJilGaeSeon(瘡疾疥癬) are wind-heat(風熱), blood fever with wind transformation(血熱風動), wind-damp(風濕), the treatment of wind-dispelling(疏風) with Arctii Fructus(牛蒡子), Schizonepetae Herba(荊芥), Ledebouriellae Radix(防風), Dictamni Radicis Cortex(白鮮皮), Bombyx Batrytioatus(白？?), etc can be applied. 3) When the pathogenesis of SaHuHaeSu(사후해수), SaJin(사진), BalJin(發疹), EunJin(은진) and BuYang(부양) are wind-heat(風熱), exogenous cold with endogenous heat(外寒內熱), exogenous warm pathogen with endogenous damp-heat(溫邪外感 濕熱內蘊), warm pathogen's penetration(溫邪內陷), insidious heat's penetration of pericardium(伏熱入包絡), the treatment of Ki-cooling(淸氣) with TongSeongHwan(通聖丸), Praeparatum(豆？), Phyllostachys Folium(竹葉), Mori Cortex(桑白皮), Tetrapanacis Medulla(通草), etc can be applied. 4) When the pathogenesis of JeokBan(적반), BalLa(발라), GuChang(久瘡), GyeolHaek(結核), DamHaek(痰核), Yeong(？), YuJu(流注), Breast Diseases(乳房疾患) and DoHan(盜汗) are stagnancy's injury of Ki and blood(鬱傷氣血), gallbladder fire with stomach damp(膽火胃濕), deficiency of Yin in stomach with Kwolum's check (胃陰虛 厥陰乘), heat's penetration of blood collaterals with disharmony of liver and stomach(熱入血絡 肝胃不和), insidious pathogen in Kwolum(邪伏厥陰), the treatment of mediation(和解) with Prunellae Spica(夏枯草), Chrysanthemi Flos(菊花), Mori Folium (桑葉), Bupleuri Radix(柴胡), Coptidis Rhizoma(黃連), Scutellariae Radix(黃芩), Gardeniae Fructus(梔子), Cyperi Rhizoma(香附子), Toosendan Fructus(川？子), Curcumae Radix(鬱金), Moutan Cortex(牧丹皮), Paeoniae Radix Rubra(赤芍藥), Unoariae Ramulus Et Uncus(釣鉤藤), Cinnamorni Ramulus(桂枝), Paeoniae Radix Alba(白芍藥), Polygoni Multiflori Radix (何首烏), Cannabis Fructus (胡麻子), Ostreae Concha(牡蠣), Zizyphi Spinosae Semen(酸棗仁), Pinelliae Rhizoma(半夏), Poria(백복령). etc can be applied. 5) When the pathogenesis of BanJin(반진), BalLa(발라), ChangI(瘡痍), NamgChang(膿瘡). ChangJilGaeSeon(瘡疾疥癬), ChangYang(瘡瘍), SeoYang(署瘍), NongYang(膿瘍) and GweYang(潰瘍) are wind-damp(風濕), summer heat-damp(暑濕), damp-warm(濕溫), downward flow of damp-heat(濕熱下垂), damp-heat with phlegm transformation(濕熱化痰), gallbladder fire with stomach damp(膽火胃濕), overdose of cold herbs(寒凉之樂 過服), the treatment of damp-resolving(化濕) with Pinelliae Rhizoma(半夏), armeniacae Amarum Semen(杏仁), Arecae Pericarpium(大腹皮), Poria(백복령), Coicis Semen(薏苡仁), Talcum(滑石), Glauberitum(寒水石), Dioscoreae Tokoro Rhizoma(？？), Alismatis Rhizoma(澤瀉), Phellodendri Cortex(黃柏), Phaseoli Radiati Semen(？豆皮), Bombycis Excrementum(?沙), Bombyx Batryticatus(白？?), Stephaniae Tetrandrae Radix(防己), etc can be applied. 6) When the pathogenesis of ChangPo(瘡泡), hepatic abscess(肝癰) and appendicitis(腸癰) are food poisoning(食物中毒), Ki obstruction & blood stasis in the interior(기비혈어재과), damp-heat stagnation with six Bu organs suspension(濕熱結聚 六腑不通), the treatment of purgation(通下) with DaeHwangMokDanPiTang(大黃牧丹皮湯), Manitis Squama(穿山甲), Curcumae Radix(鬱金), Curcumae Longae Rhizoma(薑黃), Tetrapanacis Medulla(通草), etc can be applied. 7) When the pathogenesis of JeokBan(적반), BanJin(반진), EunJin(은진). BuYang(부양), ChangI(瘡痍), ChangPo(瘡泡), GuChang(久瘡), NongYang(膿瘍), GweYang(潰瘍), Jeong(정), Jeol(癤), YeokRyeo(疫？) and YeokRyeolpDan(疫？入？) are wind-heat stagnation(風熱久未解), blood fever in Yangmyong(陽明血熱), blood fever with transformation(血熱風動), heat's penetration of blood collaterals(熱入血絡). fever in blood(血分有熱), insidious heat in triple energizer(三焦伏熱), pathogen's penetration of pericardium(心包受邪), deficiency of Yong(營虛), epidemic pathogen(感受穢濁), the treatment of Yong & blood-cooling(淸營凉血) with SeoGakJiHwangTang(犀角地黃湯), Scrophulariae Radix(玄參), Salviae Miltiorrhizae Radix(丹參), Angelicae Gigantis Radix(當歸), Polygoni Multiflori Radix(何首烏), Cannabis Fructus(胡麻子), Biotae Semen(柏子仁), Liriopis Tuber(麥門冬), Phaseoli Semen(赤豆皮), Forsythiae Fructus(連翹), SaJin(사진), YangDok(瘍毒) and YeokRyeoIpDan(역려입단) are insidious heat's penetration of pericardium(伏熱入包絡), damp-warm's penetration of blood collaterals(濕溫入血絡), epidemic pathogen's penetration of pericardium(심포감수역려), the treatment of resuscitation(開竅) with JiBoDan(至寶丹), UHwangHwan(牛黃丸), Forsythiae Fructus(連翹), Curcumae Radix(鬱金), Tetrapanacis Medulla(通草), Acori Graminei Rhizoma(石菖蒲), etc can be applied. 9) When the pathogenesis of SaHuSinTong(사후신통), SaHuYeolBuJi(사후열부지), ChangI(瘡痍), YangSon(瘍損) and DoHan(盜汗) are deficiency of Yin in Yangmyong stomach(陽明胃陰虛), deficiency of Yin(陰虛), the treatment of Yin-replenishing(滋陰) with MaekMunDongTang(麥門冬湯), GyeongOkGo(瓊玉膏), Schizandrae Fructus(五味子), Adenophorae Radix(沙參), Lycii Radicis Cortex (地骨皮), Polygonati Odorati Rhizoma(玉竹), Dindrobii Herba(石斛), Paeoniae Radix Alba(白芍藥), Ligustri Lucidi Fructus (女貞子), etc can be applied. 10) When the pathogenesis of RuYang(漏瘍) is endogenous wind in Yang collaterals(陽絡內風), the treatment of endogenous wind-calming(息風) with Mume Fructus(烏梅), Paeoniae Radix Alba (白芍藥), etc be applied. 11) When the pathogenesis of GuChang(久瘡), GweYang(潰瘍), RuYang(漏瘍), ChiChang(痔瘡), JaHan(自汗) and OSimHan(五心汗) are consumption of stomach(胃損), consumption of Ki & blood(氣血耗盡), overexertion of heart vitality(勞傷心神), deficiency of Yong(營虛), deficiency of Wi(衛虛), deficiency of Yang(陽虛), the treatment of Yang-restoring & exhaustion-arresting(回陽固脫) with RijungTang(理中湯), jinMuTang(眞武湯), SaengMaekSaGunjaTang(生脈四君子湯), Astragali Radix (황기), Ledebouriellae Radix(防風), Cinnamomi Ramulus(桂枝), Angelicae Gigantis Radix(當歸), Ostreae Concha(牡蠣), Zanthoxyli Fructus(川椒), Cuscutae Semen(兎絲子), etc can be applied.

• Journal of Intelligence and Information Systems
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• v.17 no.4
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• pp.143-155
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• 2011

Lately electronic tagging policy for the sexual offenders was introduced in order to reduce and prevent sexual offences. However, most sexual offences against children happening these days are committed by the tagged offenders whose identities have been released. So, for the crime prevention, we need measures with which we could minimize the suffers more promptly and actively. This paper suggests a new system to relieve the sexual abuse related anxiety of the children and solve the problems that electronic bracelet has. Existing bracelets are only worn by serious criminals, and it's only for risk management and positioning, there is no way to protect the children who are the potential victims of sexual abuse and there actually happened some cases. So we suggest also letting the students(children) wear the LBS(Location Based Service) and USN(Ubiquitous Sensor Network) technology based electronic bracelets to monitor and figure out dangerous situations intelligently, so that we could prevent sexual offences against children beforehand, and while a crime is happening, we could judge the situation of the crime intelligently and take swift action to minimize the suffer. And by checking students' attendance and position, guardians could know where their children are in real time and could protect the children from not only sexual offences but also violent crimes against children like kidnapping. The overall system is like follows : RFID Tag for children monitors the approach of offenders. While an offender's RFID tag is approaching, it will transmit the situation and position as the first warning message to the control center and the guardians. When the offender is going far away, it turns to monitoring mode, and if the tag of the child or the offender is taken off or the child and offender stay at one position for 3~5 minutes or longer, then it will consider this as a dangerous situation, then transmit the emergency situations and position as the second warning message to the control center and the guardians, and ask for the dispatch of police to prevent the crime at the initial stage. The RFID module of criminals' electronic bracelets is RFID TAG, and the RFID module for the children is RFID receiver(reader), so wherever the offenders are, if an offender is at a place within 20m from a child, RFID module for children will transmit the situation every certain periods to the control center by the automatic response of the receiver. As for the positioning module, outdoors GPS or mobile communications module(CELL module)is used and UWB, WI-FI based module is used indoors. The sensor is set under the purpose of making it possible to measure the position coordinates even indoors, so that one could send his real time situation and position to the server of central control center. By using the RFID electronic roll book system of educational institutions and safety system installed at home, children's position and situation can be checked. When the child leaves for school, attendance can be checked through the electronic roll book, and when school is over the information is sent to the guardians. And using RFID access control turnstiles installed at the apartment or entrance of the house, the arrival of the children could be checked and the information is transmitted to the guardians. If the student is absent or didn't arrive at home, the information of the child is sent to the central control center from the electronic roll book or access control turnstiles, and look for the position of the child's electronic bracelet using GPS or mobile communications module, then send the information to the guardians and teacher so that they could report to the police immediately if necessary. Central management and control system is built under the purpose of monitoring dangerous situations and guardians' checking. It saves the warning and pattern data to figure out the areas with dangerous situation, and could help introduce crime prevention systems like CCTV with the highest priority. And by DB establishment personal data could be saved, the frequency of first and second warnings made, the terminal ID of the specific child and offender, warning made position, situation (like approaching, taken off of the electronic bracelet, same position for a certain time) and so on could be recorded, and the data is going to be used for preventing crimes. Even though we've already introduced electronic tagging to prevent recurrence of child sexual offences, but the crimes continuously occur. So I suggest this system to prevent crimes beforehand concerning the children's safety. If we make electronic bracelets easy to use and carry, and set the price reasonably so that many children can use, then lots of criminals could be prevented and we can protect the children easily. By preventing criminals before happening, it is going to be a helpful system for our safe life.

• Journal of Radiation Protection and Research
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• v.41 no.1
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• pp.71-79
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• 2016

Background: It is necessary to analyze radioactivity of naturally occurring radioactive materials (NORM) in products to ensure radiological safety required by Natural Radiation Safety Management Act. The pretreatments for the existing analysis methods require high technology and time. Such destructive pretreatments including grinding and dissolution of samples make impossible to reuse products. We developed a rapid and simple procedure of radioactivity analysis for thorium series in the products containing NORM. Materials and Methods: The developed method requires non-destructive or minimized pretreatment. Radioactivity of the product without pretreatment is initially measured using gamma spectroscopy and then the measured radioactivity is adjusted by considering material composition, mass density, and geometrical shape of the product. The radioactivity adjustment can be made using scaling factors, which is derived by radiation transport Monte Carlo simulation. Necklace, bracelet, male health care product, and tile for health mat were selected as representative products for this study. The products are commonly used by the public and directly contacted with human body and thus resulting in high radiation exposure to the user. Results and Discussion: The scaling factors were derived using MCNPX code and the values ranged from 0.31 to 0.47. If radioactivity of the products is measured without pretreatment, the thorium series may be overestimated by up to 2.8 times. If scaling factors are applied, the difference in radioactivity estimates are reduced to 3-24%. Conclusion : The developed procedure in this study can be used for other products with various materials and shapes and thus ensuring radiological safety.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.3
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• pp.43-47
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• 2009

Purpose: The menstrual cycle of normal premenopausal patients was divide into menstrual flow phase, proliferative phase, ovulatory phase, secretory phase. The aim of this study was to ovarian and endometrial $^{18}F$-FDG uptake during the menstrual cycle in normal premenopausal patients. Materials and Methods: We identified 200 incidental $^{18}F$-FDG uptake in the ovary. The patient fasted at least 6 hours before receiving an intravenous injection of 370-592 MBq (10-16mCi) of $^{18}F$-FDG. Scanning from the base of the skull though the mid thigh was performed using the Discovery Ste PET/CT system (GE Healthcare, Milwaukee, WI, USA). Ovarian and endometrial $^{18}F$-FDG uptake (expressed as standardized uptake value) was measured on PET/CT image. Results: Two peaks of increased endometrial $^{18}F$-FDG uptake were identified during the menstrual cycle. The $SUV_{avg}$ and $SUV_{max}$ was $2.89{\pm}1.04$ and $3.17{\pm}1.59$ in menstruating patients, $2.4{\pm}0.88$ and $2.98{\pm}1.14$ in proliferative phase patients, $3.59{\pm}1.76$ and $3.17{\pm}1.67$ in ovulatory phase patients, $2.58{\pm}1.39$ and $3.1{\pm}1.8$ in secretory phase patients. Conclusions: Increased ovarian and endometrial $^{18}F$-FDG uptake could be found the time of menstrual flow and ovulatory phase of menstrual cycle. Increased uptake in endometrial adjacent to a cervical tumor does not necessarily reflect endometrial tumor invasion. Since increased uptake was dependent on the menstrual cycle, it can be avoided by scheduling PET/CT just after menstruation. Non-menstrual-related endometrial uptake may be instrumental in establishing a diagnosis in a premenopaual patient.

• Korean Chemical Engineering Research
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• v.54 no.6
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• pp.863-870
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• 2016

We investigated the physical/chemical phenomena that a slow loss of $CO_2$ inventory into sodium after the sodium-$CO_2$ boundary failure in printed circuit heat exchangers (PCHEs), which is considered for the supercritical $CO_2$ Brayton cycle power conversion system of a sodium-cooled fast reactor (SFR). The first phenomenon is plugging inside narrow sodium channels by micro cracks and the other one is damage propagation referred to as wastage combined with the corrosion/erosion effect. Experimental results of plugging shows that sodium flow immediately stopped as $CO_2$ was injected through the nozzle at $300{\sim}400^{\circ}C$ in 3 mmID sodium channels, whereas sodium flow stopped about 60 min after $CO_2$ injection in 5 mmID sodium channels. These results imply that if pressure boundary of sodium-$CO_2$ fails a narrow sodium channel would be plugged by reaction products in a short time whereas a relatively wider sodium channel would be plugged with higher concentration of reaction products. Wastage by the erosion effect of $CO_2$ (200~250 bar) hardly occurred regardless of the kinds of materials (stainless steel 316, Inconel 600, and 9Cr-1Mo steel), temperature ($400{\sim}500^{\circ}C$), or the diameter of the $CO_2$ nozzle (0.2~0.8 mm). Velocities at the $CO_2$ nozzle were specified as Mach 0.4~0.7. Our experimental results are expected to be used for determining the design parameters of PCHEs for their safeties.