• Title/Summary/Keyword: Dispersion effects

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A study on a flow of the technological convergence in webtoon - Focused on the interactiontoon of webtoon (기술 융합형 웹툰의 몰입도 연구 -인터랙션 툰 <마주쳤다>를 중심으로)

  • Baek, Eun-Ji;Son, Ki-Hwan
    • Cartoon and Animation Studies
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    • s.50
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    • pp.101-130
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    • 2018
  • Since the advent of the Smart Devices, the smartphone has become a popular tool to view Webtoon. This phenomenon has caused the convergence of cutting-edge technologies and Webtoons in diverse forms, creating unique versions of Webtoons including, but not limited to Smart-toon, Effect-toon, Cut-toon, Dubbing-toon, Moving-toon, AR-toon, VR-toon, and Interaction-toon. By comparison to these rich diversities of Webtoons in the online industry, there is a lack of academic research on this topic. There are some papers which talk about the different types of multimedia technology conversion and its case presentation or the effectiveness and problems of visual effect, but the effects of these convergence technologies on comic readers' concentration and reading effectiveness have never been investigated so far. Therefore, this paper will discuss the unique method of immersive storytelling that is often used in comics and analyze each aspects of immersive method in technology-converged Webtoons along with its problems. Furthermore, this paper will analyze different aspects of "immersion" and interaction elements that can be found in the popular Interaction-toon, (Encountered). Through this, this paper discusses the positive influence of the interaction elements on comic readers' immersion level and its limitation. To classify the technology-converged Webtoons in terms of the immersion level, the Effect-toon sometimes interferes viewer's flow by using excessive use of multimedia effect, creating information overload. The Smart-toon which applied motions to each frame under horizontal mode of smartphones was a good try, but it hindered the readers' activeness and made it hard for the readers to be fully absorbed in the story. The VR-toon, which utilizes virtual reality gadgets to allow viewers to explore the world of Webtoon was also a nice try to overcome the limitation of vertical screens. However, it often caused dispersion of user's attention and reduced the users' immersion level. The Moving-toon which only emphasized the reading convenience also invaded readers' activeness and disturb users' concentration. On the other hand, the cartoonist Il-Kwon Ha applied high technologies such as face recognition technology, augmented reality techniques, 360-degree panorama technology, and haptic technology to his cartoon (Encountered). This allowed the readers to form a sense of closeness towards the cartoon characters which let the readers to identify themselves with the characters and interact with them. By this way, the readers can be fully immersed in the story. However, technology abuse, impractical production and hackneyed storylining often showed later in the story remains as its limitations.

Study on Effect of Convection Current Aeration System on Mixing Characteristics and Water Quality of Reservoir (대류식 순환장치의 저수지수체 유동특성 및 수질영향)

  • Lee, Yo-Sang;Lee, Kwang-Man;Koh, Deok-Koo;Yum, Kyung-Taek
    • Korean Journal of Ecology and Environment
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    • v.42 no.1
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    • pp.85-94
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    • 2009
  • This study examines the operational effectiveness of a Convection Current Aeration System (CCAS) in reservoir. CCAS was run from June, 2008 when the thermocline begun forming in the reservoir. This paper reviews the influence of stratification, dissolved oxygen dynamics and temperature in the lake's natural state from June to October 2008. The survey was done on a week basis. Upwelling flow effects a radius of $7{\sim}10m$ at a surface directly and was irrelevant to the strength of thermocline. On the other hand, it was affected the number of working days, and strength of thermocline at vertical profiles of the reservoir. Longer CCAS run, the deeper was the vertical direct flow area. However it didn't break the thermocline during summer season of 2008. The operating efficiency of the CCAS in the reservoir depends on hydraulics and meteological conditions. Computational Fluid Dynamics (CFD) is a very useful tool for evaluating the operating efficiency of fluid dynamics. The geometry for CFD simulation consists of a cylindrical vessel 25 m radius and 40 m height. The CCAS is located in center of domain. The non-uniform tetrahedral meshes had a bulk of the geometry. The meshes ranged from the coarse to the very fine. This is attributed to the cold water flowing into the downcomer and rising, creating a horizontal flow to the top of the CCAS. The result of CFD demonstrate a closer agreement with surveyed data for temperature and flow velocity. Theoretical dispersion volume were calculated at 8m depth, 120 m diameter working for 30 days and 10 m depth, 130 m diameter working for 50 days.

Decomposition of Eco-friendly Liquid Propellants over Platinum/Hexaaluminate Pellet Catalysts (백금/헥사알루미네이트 펠렛 촉매를 이용한 친환경 액체 추진제 분해)

  • Jo, Hyeonmin;You, Dalsan;Kim, Munjeong;Woo, Jaegyu;Jung, Kyeong Youl;Jo, Young Min;Jeon, Jong-Ki
    • Clean Technology
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    • v.24 no.4
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    • pp.371-379
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    • 2018
  • The objective of this study is to develop a platinum/hexaaluminate pellet catalyst for the decomposition of eco-friendly liquid propellant. Pellet catalysts using hexaaluminate prepared by ultrasonic spray pyrolysis as a support and platinum as an active metal were prepared by two methods. In the case of the pellet catalyst formed by loading the platinum precursor onto the hexaaluminate powder and then adding the binder (M1 method catalyst), the mesopores were well developed in the catalyst after calcination at $550^{\circ}C$. However, when this catalyst was calcined at $1,200^{\circ}C$, the mesopores almost collapsed and only a few macropores existed. On the other hand, in the case of a catalyst in which platinum was supported on pellets after the pellet was produced by extrusion of hexaaluminate (M2 method catalyst), the surface area and the mesopores were well maintained even after calcination at $1,200^{\circ}C$. Also, the catalyst prepared by the M2 method showed better heat resistance in terms of platinum dispersion. The effects of preparation method and calcination temperature of Pt/hexaaluminate pellet catalysts on the decomposition of liquid propellant composed mainly of ammonium dinitramide (ADN) or hydroxyl ammonium nitrate (HAN) were investigated. It was confirmed that the decomposition onset temperature during the decomposition of ADN- or HAN- based liquid propellant could be reduced significantly by using Pt/hexaaluminate pellet catalysts. Especially, in the case of the catalyst prepared by the M2 method, the decomposition onset temperature did not show a large change even when the calcination temperature was raised at $1,200^{\circ}C$. Therefore, it was confirmed that Pt/ hexaaluminate pellet catalyst prepared by M2 method has heat resistance and potential as a catalyst for the decomposition of the eco-friendly liquid propellants.

Solvothermal Preparation of Nanocrystalline TiO2 Using Alcohol-water Mixed Solvent (알코올-물 혼합용액을 이용하는 Solvothermal 법에 의한 나노크기의 TiO2 제조)

  • Lee, Sang Geun;Park, Seong Soo;Hong, Seong Soo;Park, Jong Myung;Lee, Seung Ho;Kim, Dae Sung;Lee, Gun Dae
    • Applied Chemistry for Engineering
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    • v.22 no.6
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    • pp.685-690
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    • 2011
  • In this study, a solvothermal reaction to prepare nanocrystalline titania was carried out using $TiCl_4$ and mixed solvents of alcohol and water. The effects of the type and the composition of alcohol on the crystal structure and agglomeration of final $TiO_2$ products were investigated. The products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) as well as scanning electron microscopy (SEM). In the solvothermal reaction using the n-butanol solutions with different volume ratios of n-butanol/water (100/0, 75/25, 50/50, 25/75, 0/100), the extent of agglomeration of obtained rutile $TiO_2$ was found to change with the volume ratio of n-butanol/water, and the n-butanol/water ratio of 75/25 revealed the best result for the preparation of well-dispersed nanocrystalline $TiO_2$ powders. The crystal phase of $TiO_2$ prepared through the solvothermal reaction changed with the type of alcohol in solvent (alcohol/water = 75/25). $TiO_2$ products obtained with the aqueous solutions of methanol, ethanol and isopropanol have an anatase phase, while that with n-butanol has a rutile phase. The results showed that, in the solvothermal reaction using both $TiCl_4$ as a starting material and the alcohol-water mixed solvents without any other additive, the enhancement of dispersion and control of crystal structure of $TiO_2$ products can be feasible by simply varying the composition and type of alcohol in the mixed solvents.

Ammonia Decomposition over Ni Catalysts Supported on Zeolites for Clean Hydrogen Production (청정수소 생산을 위한 암모니아 분해 반응에서 Ni/Zeolite 촉매의 반응활성에 관한 연구)

  • Jiyu Kim;Kyoung Deok Kim;Unho Jung;Yongha Park;Ki Bong Lee;Kee Young Koo
    • Journal of the Korean Institute of Gas
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    • v.27 no.3
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    • pp.19-26
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    • 2023
  • Hydrogen, a clean energy source free of COx emissions, is poised to replace fossil fuels, with its usage on the rise. Despite its high energy content per unit mass, hydrogen faces limitations in storage and transportation due to its low storage density and challenges in long-term storage. In contrast, ammonia offers a high storage capacity per unit volume and is relatively easy to liquefy, making it an attractive option for storing and transporting large volumes of hydrogen. While NH3 decomposition is an endothermic reaction, achieving excellent low-temperature catalytic activity is essential for process efficiency and cost-effectiveness. The study examined the effects of different zeolite types (5A, NaY, ZSM5) on NH3 decomposition activity, considering differences in pore structure, cations, and Si/Al-ratio. Notably, the 5A zeolite facilitated the high dispersion of Ni across the surface, inside pores, and within the structure. Its low Si/Al ratio contributed to abundant acidity, enhancing ammonia adsorption. Additionally, the presence of Na and Ca cations in the support created medium basic sites that improved N2 desorption rates. As a result, among the prepared catalysts, the 15 wt%Ni/5A catalyst exhibited the highest NH3 conversion and a high H2 formation rate of 23.5 mmol/gcat·min (30,000 mL/gcat·h, 600 ℃). This performance was attributed to the strong metal-support interaction and the enhancement of N2 desorption rates through the presence of medium basic sites.

The Concentration of Economic Power in Korea (경제력집중(經濟力集中) : 기본시각(基本視角)과 정책방향(政策方向))

  • Lee, Kyu-uck
    • KDI Journal of Economic Policy
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    • v.12 no.1
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    • pp.31-68
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    • 1990
  • The concentration of economic power takes the form of one or a few firms controlling a substantial portion of the economic resources and means in a certain economic area. At the same time, to the extent that these firms are owned by a few individuals, resource allocation can be manipulated by them rather than by the impersonal market mechanism. This will impair allocative efficiency, run counter to a decentralized market system and hamper the equitable distribution of wealth. Viewed from the historical evolution of Western capitalism in general, the concentration of economic power is a paradox in that it is a product of the free market system itself. The economic principle of natural discrimination works so that a few big firms preempt scarce resources and market opportunities. Prominent historical examples include trusts in America, Konzern in Germany and Zaibatsu in Japan in the early twentieth century. In other words, the concentration of economic power is the outcome as well as the antithesis of free competition. As long as judgment of the economic system at large depends upon the value systems of individuals, therefore, the issue of how to evaluate the concentration of economic power will inevitably be tinged with ideology. We have witnessed several different approaches to this problem such as communism, fascism and revised capitalism, and the last one seems to be the only surviving alternative. The concentration of economic power in Korea can be summarily represented by the "jaebol," namely, the conglomerate business group, the majority of whose member firms are monopolistic or oligopolistic in their respective markets and are owned by particular individuals. The jaebol has many dimensions in its size, but to sketch its magnitude, the share of the jaebol in the manufacturing sector reached 37.3% in shipment and 17.6% in employment as of 1989. The concentration of economic power can be ascribed to a number of causes. In the early stages of economic development, when the market system is immature, entrepreneurship must fill the gap inherent in the market in addition to performing its customary managerial function. Entrepreneurship of this sort is a scarce resource and becomes even more valuable as the target rate of economic growth gets higher. Entrepreneurship can neither be readily obtained in the market nor exhausted despite repeated use. Because of these peculiarities, economic power is bound to be concentrated in the hands of a few entrepreneurs and their business groups. It goes without saying, however, that the issue of whether the full exercise of money-making entrepreneurship is compatible with social mores is a different matter entirely. The rapidity of the concentration of economic power can also be traced to the diversification of business groups. The transplantation of advanced technology oriented toward mass production tends to saturate the small domestic market quite early and allows a firm to expand into new markets by making use of excess capacity and of monopoly profits. One of the reasons why the jaebol issue has become so acute in Korea lies in the nature of the government-business relationship. The Korean government has set economic development as its foremost national goal and, since then, has intervened profoundly in the private sector. Since most strategic industries promoted by the government required a huge capacity in technology, capital and manpower, big firms were favored over smaller firms, and the benefits of industrial policy naturally accrued to large business groups. The concentration of economic power which occured along the way was, therefore, not necessarily a product of the market system. At the same time, the concentration of ownership in business groups has been left largely intact as they have customarily met capital requirements by means of debt. The real advantage enjoyed by large business groups lies in synergy due to multiplant and multiproduct production. Even these effects, however, cannot always be considered socially optimal, as they offer disadvantages to other independent firms-for example, by foreclosing their markets. Moreover their fictitious or artificial advantages only aggravate the popular perception that most business groups have accumulated their wealth at the expense of the general public and under the behest of the government. Since Korea stands now at the threshold of establishing a full-fledged market economy along with political democracy, the phenomenon called the concentration of economic power must be correctly understood and the roles of business groups must be accordingly redefined. In doing so, we would do better to take a closer look at Japan which has experienced a demise of family-controlled Zaibatsu and a success with business groups(Kigyoshudan) whose ownership is dispersed among many firms and ultimately among the general public. The Japanese case cannot be an ideal model, but at least it gives us a good point of departure in that the issue of ownership is at the heart of the matter. In setting the basic direction of public policy aimed at controlling the concentration of economic power, one must harmonize efficiency and equity. Firm size in itself is not a problem, if it is dictated by efficiency considerations and if the firm behaves competitively in the market. As long as entrepreneurship is required for continuous economic growth and there is a discrepancy in entrepreneurial capacity among individuals, a concentration of economic power is bound to take place to some degree. Hence, the most effective way of reducing the inefficiency of business groups may be to impose competitive pressure on their activities. Concurrently, unless the concentration of ownership in business groups is scaled down, the seed of social discontent will still remain. Nevertheless, the dispersion of ownership requires a number of preconditions and, consequently, we must make consistent, long-term efforts on many fronts. We can suggest a long list of policy measures specifically designed to control the concentration of economic power. Whatever the policy may be, however, its intended effects will not be fully realized unless business groups abide by the moral code expected of socially responsible entrepreneurs. This is especially true, since the root of the problem of the excessive concentration of economic power lies outside the issue of efficiency, in problems concerning distribution, equity, and social justice.

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A Study on the long-term Hemodialysis patient중s hypotension and preventation from Blood loss in coil during the Hemodialysis (장기혈액투석환자의 투석중 혈압하강과 Coil내 혈액손실 방지를 위한 기초조사)

  • 박순옥
    • Journal of Korean Academy of Nursing
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    • v.11 no.2
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    • pp.83-104
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    • 1981
  • Hemodialysis is essential treatment for the chronic renal failure patient's long-term cure and for the patient management before and after kidney transplantation. It sustains the endstage renal failure patient's life which didn't get well despite strict regimen and furthermore it becomes an essential treatment to maintain civil life. Bursing implementation in hemodialysis may affect the significant effect on patient's life. The purpose of this study was to obtain the basic data to solve the hypotension problem encountable to patient and the blood loss problem affecting hemodialysis patient'a anemic states by incomplete rinsing of blood in coil through all process of hemodialysis. The subjects for this study were 44 patients treated hemodialysis 691 times in the hemodialysis unit, The .data was collected at Gang Nam 51. Mary's Hospital from January 1, 1981 to April 30, 1981 by using the direct observation method and the clinical laboratory test for laboratory data and body weight and was analysed by the use of analysis of Chi-square, t-test and anlysis of varience. The results obtained an follows; A. On clinical laboratory data and other data by dialysis Procedure. The average initial body weight was 2.37 ± 0.97kg, and average body weight after every dialysis was 2.33 ± 0.9kg. The subject's average hemoglobin was 7.05±1.93gm/dl and average hematocrit was 20.84± 3.82%. Average initial blood pressure was 174.03±23,75mmHg and after dialysis was 158.45±25.08mmHg. The subject's average blood ion due to blood sample for laboratory data was 32.78±13.49cc/ month. The subject's average blood replacement for blood complementation was 1.31 ±0.88 pint/ month for every patient. B. On the hypotensive state and the coping approaches occurrence rate of hypotension was 28.08%. It was 194 cases among 691 times. 1. In degrees of initial blood pressure, the most 36.6% was in the group of 150-179mmHg, and in degrees of hypotension during dialysis, the most 28.9% in the group of 40-50mmHg, especially if the initial blood pressure was under 180mmHg, 59.8% clinical symptoms appeared in the group of“above 20mmHg of hypotension”. If initial blood pressure was above 180mmHg, 34.2% of clinical symptoms were appeared in the group of“above 40mmHg of hypotension”. These tendencies showed the higher initial blood pressure and the stronger degree of hypotension, these results showed statistically singificant differences. (P=0.0000) 2. Of the occuring times of hypotension,“after 3 hrs”were 29.4%, the longer the dialyzing procedure, the stronger degree of hypotension ann these showed statistically significant differences. (P=0.0142). 3. Of the dispersion of symptoms observed, sweat and flush were 43.3%, and Yawning, and dizziness 37.6%. These were the important symptoms implying hypotension during hemodialysis accordingly. Strages of procedures in coping with hypotension were as follows ; 45.9% were recovered by reducing the blood flow rate from 200cc/min to 1 00cc/min, and by reducing venous pressure to 0-30mmHg. 33.51% were recovered by controling (adjusting) blood flow rate and by infusion of 300cc of 0,9% Normal saline. 4.1% were recovered by infusion of over 300cc of 0.9% normal saline. 3.6% by substituting Nor-epinephiine, 5.7% by substituting blood transfusion, and 7,2% by substituting Albumin were recovered. And the stronger the degree of symptoms observed in hypotention, the more the treatments required for recovery and these showed statistically significant differences (P=0.0000). C. On the effects of the changes of blood pressure and osmolality by albumin and hemofiltration. 1. Changes of blood pressure in the group which didn't required treatment in hypotension and the group required treatment, were averaged 21.5mmHg and 44.82mmHg. So the difference in the latter was bigger than the former and these showed statistically significant difference (P=0.002). On the changes of osmolality, average mean were 12.65mOsm, and 17.57mOsm. So the difference was bigger in the latter than in the former but these not showed statistically significance (P=0.323). 2. Changes of blood pressure in the group infused albumin and in the group didn't required treatment in hypotension, were averaged 30mmHg and 21.5mmHg. So there was no significant differences and it showed no statistical significance (P=0.503). Changes of osmolality were averaged 5.63mOsm and 12.65mOsm. So the difference was smaller in the former but these was no stitistical significance (P=0.287). Changes of blood pressure in the group infused Albumin and in the group required treatment in hypotension were averaged 30mmHg and 44.82mmHg. So the difference was smaller in the former but there is no significant difference (P=0.061). Changes of osmolality were averaged 8.63mOsm, and 17.59mOsm. So the difference were smaller in the former but these not showed statistically significance (P=0.093). 3. Changes of blood pressure in the group iutplemented hemofiltration and in the Uoup didn't required treatment in hypotension were averaged 22mmHg and 21.5mmHg. So there was no significant differences and also these showed no statistical significance (P=0.320). Changes of osmolality were averaged 0.4mOsm and 12.65mOsm. So the difference was smaller in the former but these not showed statistical significance(P=0.199). Changes of blood pressure in the group implemented hemofiltration and in the group required treatment in hypotension were averaged 22mmHg and 44.82mmHg. So the difference was smatter in the former and these showed statistically significant differences (P=0.035). Changes of osmolality were averaged 0.4mOsm and 17.59mOsm. So the difference was smaller in the former but these not showed statistical significance (P=0.086). D. On the changes of body weight, and blood pressure, between the group of hemofiltration and hemodialysis. 1, Changes of body weight in the group implemented hemofiltration and hemodialysis were averaged 3.340 and 3.320. So there was no significant differences and these showed no statistically significant difference, (P=0.185) but standard deviation of body weight averaged in comparison with standard difference of body weight was statistically significant difference (P=0.0000). Change of blood Pressure in the group implemented hemofiltration and hemodialysis were averaged 17.81mmHg and 19.47mmHg. So there was no significant differences and these showed no statistically significant difference (P=0.119), But in comparison with standard deviation about difference of blood pressure was statistically significant difference. (P=0.0000). E. On the blood infusion method in coil after hemodialysis and residual blood losing method in coil. 1, On comparing and analysing Hct of residual blood in coil by factors influencing blood infusion method. Infusion method of saline 200cc reduced residual blood in coil after the quantitative comparison of Saline Occ, 50cc, 100cc, 200cc and the differences showed statistical significance (p < 0.001). Shaking Coil method reduced residual blood in Coil in comparison of Shaking Coil method and Non-Shaking Coil method this showed statistically significant difference (P < 0.05). Adjusting pressure in Coil at OmmHg method reduced residual blood in Coil in comparison of adjusting pressure in Coil at OmmHg and 200mmHg, and this showed statistically significant difference (P < 0.001). 2. Comparing blood infusion method divided into 10 methods in Coil with every factor respectively, there was seldom difference in group of choosing Saline 100cc infusion between Coil at OmmHg. The measured quantity of blood loss was averaged 13.49cc. Shaking Coil method in case of choosing saline 50cc infusion while adjusting pressure in coil at OmmHg was the most effective to reduce residual blood. The measured quantity of blood loss was averaged 15.18cc.

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