• Korean Journal of Materials Research
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• v.8 no.8
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• pp.737-743
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• 1998

The synthesis of $SrAI_2O_4:Eu^{2+}$ phosphor and its properties of both photoluminescence and long-phosphorescent were investigated as a function of sintering condition. Single phase of $SrAl_2O_4$ was obtained by sintering the mixtures of $SrCO_3$, $Eu_2O_3$, $AI_2O_34 and 3wt% $B_2O_3$ powders over 100$0^{\circ}C$ in Ar/H2 atmosphere. The optimum sintering condition for the long-phosphorescent phosphor of $SrAI_2O_4:Eu^{2+}$ was found at 130$0^{\circ}C$ for 3hours. The PL emission spectrum of $SrAI_2O_4:Eu^{2+}$ shows a maximum peak intensity at 520nm(2.384eV) with a broad emission extending from 450 to 650nm which resulted from the $4f^65d^1$$\rightarrow$$4f^7$ transition of $Eu^{+2}$ under 360nm exitation. Monitored at 520nm. the excita¬tion spectrum of $SrAI_2O_4:Eu^{2+}$ exhibits a maximum peak intensity at 360nm (3.44eV) with a broad absorption band extending from 250 to 480nm.

• Journal of the Microelectronics and Packaging Society
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• v.24 no.2
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• pp.49-53
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• 2017

We study on the change of electrical properties of two-dimensional (2D) $SnSe_2$ materials with respect to Cl doping as $SnSe_{1.994}Cl_{0.006}$ under a high temperature condition. (300~450 K) By the simple solid-state reaction method, non-and Cl-doped 2D $SnSe_2$ materials are successfully synthesized with negligible impurities as confirmed by X-ray diffraction. From the temperature dependence of resistivity, it is observed that the conduction mechanism is changed from hopping to degenerate conduction with Cl doping. By Hall effect measurement, an increase on electron carrier concentration from ${\sim}7{\times}10^{16}$ to ${\sim}3{\times}10^{18}cm^{-3}$ with Cl doping verifies that Cl is an effective electron donor which results in the encouraged carrier concentration. Detailed analysis for temperature dependent Hall mobility reveals that the electrical transports in high temperature regime are governed by the grain boundary-controlled mechanism for non-doped $SnSe_2$, which is effectively suppressed by Cl-doping as entering metallic transport regime.

• The Journal of the Acoustical Society of Korea
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• v.40 no.4
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• pp.320-329
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• 2021

In this paper, an empirical model of air bubble size to be applied to an air masker for reduction of underwater radiation noise is presented. The proposed model improves the divergence problem under the low-speed flow condition of the existing model derived using Rayleigh's jet instability model and simple continuity condition by introducing a jet flow velocity of air. The jet flow velocity of air is estimated using the bubble size where the liquid is quiescent. In a medium without flow, the size of the bubble is estimated by an empirical method where bubble formation regime is divided into a laminar-flow range, a transition range, and a turbulent-flow range based on the Reynolds number of the injected air. The proposed bubble size model is confirmed to be in good agreement with the Computational Fluid Dynamics (CFD) analysis result and the experimental results of the existing literature. Using the acoustic inversion method, the air bubble population is estimated from the insertion loss measured during the air injection experiment of the air- masker model in a large cavitation tunnel. The results of the experiments and the bubble size model are compared in the paper.

• Journal of Korean Public Health Nursing
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• v.10 no.2
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• pp.103-118
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• 1996

It is to be growing up the interest of community health affairs through visiting nursing care. The health medical treatment of Korea has been changed largely on the period. The juvenile population has decreased. This means that is has took the population consensus of advanced national organization to be increased by the old age. The transition of disease has changed from the contagious disease importance to the chronicity disease omportance because the domestic district population has experienced the sudden urbanization circumstance district population has experienced the sudden urbanization circumstance to be growing up $70\%$ of the whole population. When the nursing service has common function to be delivering from all direction to home, this study is getting the great important phase velocity in order to manage the kernel questional adult chronicity disease of health medical institution at the present age. (1) community over system or with people particularity (2) the first of third step medical treatments. The variety of medical treatments organization has quantity of the delivery manpower and specially between consumers and rdlated person. A qualitative difference is showed at the purpose to be seizing. That research related person is use at district health center in Seoul, by foundation on nurse registration book of H collage hospital and public health registration book. According the chronicity disease. age. and sex. nature agree-able standard 54 people took the content analysis on nurse registration book of total 108 people. The results of the study were as follows: 1. General background factors are houses or kind of medical facilities and number of patients in family. The first medical treatment is more patients than third medical treatment organization. The first medical treatment of economic environment os appering to be worse. 2. The chronicity disease frequency have been different speciality according to medical treatment organization. On case of the first medical treatment. Diabetes and High Blood Pressure were good but Cerebrum Vascular Accident(CVA) showed many for bed case. In addition. the number of family is comparative large exception of CVA on according for moving condition and health more than the first medical treatment. However. family condition. whole family percentage is decreasing preferably through the potential resource is increasing by the number of and the construction of family. The ability of real resource is considered to be low. 3. The average percentage of nurse service has appered to be differed two groups by the first step medical treatment(33.72 times) and third step medical treatment(45.70 times). However, the difference (the first step medical treatment and third step medical treatment) is to be limited to issue the medicine at the service. The condition of nurse care was the indirect nursing care. Supportiong area was to be related to volunteer service and administration support. 4. The various nursing care average percentage of the chronicity disease was increased by orders of Diabetes. High Blood Pressure. and CVA in examination result and the medical treatment. The indirect nursing care was also same. At third step medical treatment, orders of chronicity disease were same. The case of other area on service conditions were increased by order of Diabetes. High Blood Pressure, and CVA. However. it is never appearing the difference at bottleneck affairs nursing care. 5. When the visiting nursing care demand particularly. the average percentage of nursing care from the first step medical treatment that the time under a person is many more than the time over two people. However, there was no difference in statistic. Third step medical treatment is $49.81\%$ at the time under a person. The average nursing care service is appeared by more many when the visiting nursing care demand is a few by 12.83 at the time over two people. 6. By visiting nursing care percentage to be frequency that nursing care averaghe percentage and inter-relation are large. The related factor of the first medical treatment is 0.96. However, the related factor of third medical treatment has shown the decreased 0.49 for the condition of relation more than that. Therefore. the nursing care average percentage is related to the visiting times of a nurse. This result is be showing the obvious fact that the first step medical treatment is few more than third step medical treatment.

• Korean Journal of Food Science and Technology
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• v.36 no.5
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• pp.765-772
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• 2004

Cooking condition of Tarakjuk (milk-rice porridge) was established based on gelatinization temperature using differential scanning calorimetry (DSC) of roasted Ilpum rice flour, which has highest enzyme-resistant starch (RS) content. Effect of cooking temperature and time on DSC characteristics, crystallity with X ray diffractogram, RS content, in vitro starch digestibility (IVSD), amino acid composition, and in vitro protein digestibility (IVPD) of Tarakjuk were determined. Tarakjuk was cooked at 50, 56.5, 64, and $69^{\circ}C$ for various durations. Rice flour ingredient used was Ilpum, previously roasted at $185^{\circ}C$ for 25 min. Tarakjuk cooked at 50 and $56.5^{\circ}C$ showed two thermal transitions between $63.7-125.2^{\circ}C$ as determined by DSC, corresponding to endotherms of starch gelatinization $(63.7-73.8^{\circ}C)$ and melting of amylose-lipid complex (AM-lipid complex, $97.7-125.2^{\circ}C$), whereas that cooked at 64 and $69^{\circ}C$ showed only AM-lipid complex melting transition between $96.9-127.6^{\circ}C$. As cooking temperature increased, RS content of Tarakjuk decreased, whereas IVSD increased. Total amino acid content was between 11,558-15,601mg/100g, depending on cooking condition used. Compared with conventionally made control, contents of essential amino acids, such as lysine and tryptophane, were higher at 50 and $56.5^{\circ}C$, and IVPD showed higher increase. Results reveal degree of gelatinization in Tarakjuk with high RS content as well as low IVSD and high IVPD, which are important from physiological and nutritional point of view, can be produced by controlling cooking condition.

• The Journal of Korean Philosophical History
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• no.56
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• pp.81-117
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• 2018

The purpose of this study is to clarify the overall features and its meaning of the Gaebyok(開闢) through the intercomparison of the Gaebyok idea that is the core idea of a newly risen modern religion in Korea. Limitation of most studies so far is that they have stayed in the fragmentary study on the Gaebyok idea of each new religion. In order to overcome this problem, first of all, the Gaebyok idea was studied from a philosophical point encompassing the cosmological view of time in the book of changes. And based on this methodological foundation, with organizing the existing result of study, the process of development and characteristics in the Gaebyok idea of a posteriori Donghak(東學), Right I Ching (正易), Won Buddhism(圓佛敎), and Kangjeungsan(姜甑山) was investigated respectively. And through comparing and analyzing each Gaebyok idea, the similarities and differences between each other were organized. The founders of new religions thought that a great change in the universal and natural luck was made before and after the point of their living. The concept of the frequency of revolution theory is the concept to explain the aspect of transition according to the frequency of revolution(運度) of the cosmological nature that returns to the beginning, and in the idea of the posterior Gaebyok, this content and concepts is contained as it was. This study showed that the concept of the frequency of revolution theory in an apriority and a posterior like those becomes appeared in some preaches of Suun, Ilbu, Sotaesan and Jeungsan. An apriority in the Gaebyok idea of new religion is the world of crisis that represents the limited condition of human being, and a posterity means the religious ideal world realized through the power of the absolute being or a dramatic universal change from that limited circumstances. So the Gaebyok ida is a kind of an universal eschatology and religious view that expects the coming of ideal world in the future. In addition, since the universal eschatology is a kind of a view of time, it inevitably has an issue how long time apriority and a posterity included in it have. And especially, it becomes to premise the content how the social condition and human condition change in an apriority and a posterity. Accordingly, in this study, based on the understanding of the view of time in the cosmological level, the content of answers that each newly risen religion discloses was listed and analyzed with comparison. It can be considered that Suun took charge of a mission to deliver the message through being possessed of a god in heaven who is able to be called a transcendental existence, Ilbu disclosed the coming of the world of a posterity beyond an apriority through the Book of Changes(易學), Jeungsan proclaimed himself as the absolute being who could make such a posterity and bring it, and Sotaesan proposed the Gaebyok of mind in order to meet with the world of a posterity and to live in that era.

• Korean Journal of Ecology and Environment
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• v.40 no.2
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• pp.285-293
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• 2007

The study was to determine zonal characteristics of nutrients and chlorophyll and evaluate their trophic relations in Daechung Reservoir. For this study, we compared longterm water quality data among three zones along with trophic state using 1993 to 2002 dataset, obtained from the Ministry of Environment, Korea. Total phosphorous (TP), Secchi depth (SD) and chlorophyll (CHL) showed typical longitudinal declines from the riverine to lacustrine zone, but total nitrogen (TN) was not evident. Largest seasonal variations in TP and CHL occurred during the summer monsoon from July to August. In the reservoir, ambient TN averaged 1.67 mg $L^{-1}$ and ratios of TN : TP averaged 88.04, indicating that nitrogen is not likely limited but phosphorus limitation was evident. Trophic State Index (TSI), based on CHL, TP, and SD, varied depending on the zones and seasons. Mean TSI (TP) in the riverine zone was 62 during the monsoon, indicating a hypertrophic condition, whereas the mean was 40 in the lacustrine, indicating a nearly oligotrophic. Values of TSI (CHL) showed maximum in the transition zone during the monsoon. The deviation analysis of TSI showed that about 65% of TSI (CHL)-TSI (TP) and TSI (CHL)-TSI (SD) values were less than zero and the lowest values were -42, indicating an effect of inorganic turbidity on algal growth in the reservoir. Correlation analysis of CHL vs. SD shewed greater correlation coefficient (p<0.001, r=-0.47) in the transition than other two zones (p<0.001, $r{\leq}-0.40$). Correlation analysis of TP vs. CHL was greatest in the lacustrine and TP was minimum in the lacustrine zone, indicating a lowest yield of algal biomass in the lacustrine. Overall data suggests that zonal response of chlorophyll yield at a given nutrient unit is clearly differed among the longitudinal gradients, so the management strategy such as cross sectional modelling should be provided in each zone.

• Korean Security Journal
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• no.31
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• pp.157-185
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• 2012

Today, the emergence of cyberspace and advancement of globalization caused not only the transformation of our productive and conventional life but also the revolutionary transition of use of destructive violence such as crime and warfare. This transition of environmental condition connects various security threats which separatedly existed in individual, local, national, and global levels in the past, and transformed the mechanical sum of all levels of security threats into the organic sum of multi-dimensional security threats. This article proposes that the sum of multi-dimensional security threats is caused by the interconnectivity of various different levels of security threats and the integrated interdisciplinary perspective is essential to properly understand the fundamental existence of today's security problem and the reality of fear that we face today. The holistic security, the concept proposed here, is to suggest the mode of networked response to multi-dimensional security threats. The holistic security is suggested to overcome the conventional divisional approach based on the principle of "division of labor" and bureaucratic principles, which means more concretely that national security and criminal justice are divided and intelligence, military, police, prosecution, fire-fighting, private security, and etc. are strictly separated into its own expertise and turf. Also, this article introduces integrated security approaches tried by international organization and major countries overseas with the respect of the holistic security. The author have spent some substantial experience of participant observation, meetings, seminar, conference, and expert interviews regarding the issues discussed in the article in various countries including the United States, Russia, Austria, Germany, Canada, Mexico, Israel, and Uzbekistan for the last ten years. Intelligence and information on various levels of security threats and security approaches introduced in this paper is obtained from such opportunities.

• 한국노년학
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• v.38 no.4
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• pp.1035-1055
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• 2018

The purpose of this study is to investigate the relationship between public care and family care. Public care for older adults began in 2008 with the implementation of the Long-Term Care insurance in South Korea. Although the expansion of public care has the purpose of reducing the care burden for the family, it is not easy to say whether the developments of public care system reduce the amount of family care for older family members. Theoretically, public care and family care are expected to have various relationships depending on the degree of the role and function(substitution, hierarchical compensatory, task specific, supplementation, complementarity). And literatures have showed inconsistent results depending on the country, data, and methods. In this study, we analyzed the relationship between two care types focusing on home care services for older persons. Analyses were based on data from the second(2008) to sixth(2016) waves of Korean Longitudinal Study of Ageing(KLoSA). To investigate elderly care dynamics in the households, we pooled the data for four changes between two periods(2008-2010, 2010-2012, 2012-2014, and 2014-2016). This study used an analytic sample of 262 older adults, who are aged 55 over and experienced public care at least one point of time. We used Fixed-Effects(FE) model to analyze the differences within the same individuals under the condition that time-invariant unobserved factors are controlled. This study distinguished the cases of entry into public care and other cases of exiting public care. The results showed that older people who are dependent on public care are less dependent on family care than before. In both entry and exit groups, negative relations were maintained, but in the entering stage of public care, the degree of negative relations was relatively small, whereas in the stage of maintaining or departing from public care, relatively negative relations were strong. At the beginning periods, even though public care increased, family care did not decrease significantly. On the other hand, at the time of ending public care and relying on family care, family care increased significantly. The results of this study show that the relationship between public care and family care is close to hierarchical compensatory model and varies according to the stage of caring transition. Also, it was found that the cases of transition from public care to family care have the biggest burden of elderly care than other groups.

• Korean Journal of Heritage: History & Science
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• v.50 no.3
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• pp.4-29
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• 2017

The purpose of this study is to grasp the commencement date of Korean-type bronze dagger through the chronology of Chinese data. It focuses on the fact that the same section polishing technique appears both in Korean type bronze dagger and Dongzhou type bronze dagger. Dongzhou type bronze dagger in Anqiu Shandong, in which A1 type section polishing technique is observed, was said to have been collected remains in 1958, but the clear excavation cannot be identified. Therefore, this study presents Tomb No.1 Zuojiawa Jinan, Dongzhou type bronze dagger, and associated products. As associated products, bronze weapon and bronze ware were excavated, whose periods are estimated to be in the Spring and Autumn period, the transition period of Warring States, and the former part of the China's Warring States. Accordingly, the Korean bronze dagger, excavated in the remains of the Han Peninsula appears to have run parallel with the Dongzhou type bronze dagger of the A1 type section polishing technique, excavated in China for a fixed period. In addition, the chronology of Tomb No. 61MI grave in Wanrongmiaoqian, Shanxi is estimated to range from the former part to the middle part of the China's Warring States, which is identified to be connected to the A1 type section polishing technique. Examining the data of the relative date, we can find out that the Commencement Period of the Korean type bronze dagger Culture is seen to be the transition period and the former part of the China's Warring States, which is estimated to be the 5th and 4th centuries BC. This chronology is followed by Tomb No.6512 Zhengjiawazi Shenyang, recorded as the 6th century B.C. which reveals that Liaoning type bronze dagger culture and Korean-typed Bronze Dagger Culture are naturally connected. Furthermore, the A1 type section polishing technique was distributed in the southwestern area of the Korean peninsula and Shandong, China, while the A2 type section polishing technique was distributed in the southern area of the Korean peninsula, Shanxi-Province in China, and Northern Kyushu region in Japan. Seen from the weapon-shaped bronze ware of the section polishing technique, Shanxi area(Central Plains area), China. the southwestern area of the Korean peninsula (northwest area), and Northern Kyushu region in Japan are set up as one traffic road(spreading route). This demonstrates that the section polishing technique emerged around the Han Peninsular, spreading the technique regionally.