• Journal of the Korean GEO-environmental Society
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• v.15 no.4
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• pp.5-11
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• 2014

Recently, there have been various lifeline installations constructed in the underground space of urban area due to the effective use of land. For newly installed lifelines or the management of the installed lifelines, many construction activities of excavation and backfilling are observed. Around these area, there are possibilities of collapse or excessive settlement due to the leaking of the pipe or unsatisfactory compaction of backfill material. Besides, construction costs can be saved since the on-site soils are used. The application of this liquidity filling material is not only to the lifeline installation but also to underpin the foundation under the vibrating machinery. On the evaluation of the applicability of this method to this circumstance, the strength should be investigated against the static load from the machine load as well as the vibration load from the activation of the machine. In this study, the applicability of the liquidity fill material on the foundation under the vibrating machinery is assessed via uniaxial compression and resonant column tests. The liquidity filling material consisting of the on-site soils with loess and kaolinite are tested to investigate the static and dynamic characteristics. Furthermore, the applicability of the reclaimed ash categorized as an industrial waste is evaluated for the recycle of the waste to the construction materials. The experimental results show that the shear modulus and 7 day uniaxial strength of the liquidity filling material mixed with reclaimed ash show higher than those with the on-site soils. However, the damping ratio does not show any tendency on the mixed materials.

• Journal of Oral Medicine and Pain
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• v.24 no.1
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• pp.9-24
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• 1999

Pumping into the upper joint cavity of the TMJ was done on patients who had reducible disc displacement with pain. This article discusses the change in TMJ sounds before and after the Pumping treatment. 20subjects(mean age of $32.1{\pm}10.2yr$)were selected among those who visited the department of Oral Medicine of Yonsei University for the treatment of craniomandibular dysfunctions. Through a thorough history taking, clinical exam and X-ray taking these subjects were diagnosed as reducible disc displacement patients, and they were subdivided into two groups as acute and chronic according to the time the TMJ sound was made. Sonopak was used to measure the TMJ sound before, right after and one-week after the Pumping treatment. VAS was used to measure the degree of subjective TMJ complaints(sounds and pain) before and one-week after the Pumping treatment. Vibration related items included total integral, high integral, low integral, ratio of high integral to low integral, peak amplitude, peak frequency and median frquency. 1. It was not statistically significant between the acute and chronic groups before the treatment. However, total integral, high integral, low integral, peak amplitude, peak frequency, median frequency showed to be greater in the chronic group. 2. In all the subjects, just after the Pumping treatment was done, total integral, high and low integral, peak amplitude and peak frequency significantly decreased (p<0.05). Even after one week, low integral, peak frequency and median frequency significantly decreased (p<0,05), and the TMJ sound diminished accordingly. 3. Comparing the two groups(before and right after the Pumping treatment), there was the following difference ; in the acute group, high integral, high amplitude, high frequency and median frequency significantly decreased(p<0.05). In the chronic group, total integral, high integral, low integral, ratio, peak amplitude and peak frequency significantly decreased(p<0,05). It was not statistically significant between the acute and chronic group. 4. Comparing the two groups(right after and one week after the Pumping treatment), there was the following difference : in the acute group, high integral, high amplitude, high frequency and median frequency significantly decreased(p<0.05), In the chronic group, low integral significantly decreased(p<0.05). However, although it was not statistically significant, after one week, there was an increase in total integral, ratio, peak amplitude and peak frequency compared to right after the treatment group. 5. In the VAS of before and one week after the Pumping treatment of the TMJ pain and sound, the TMJ pain significantly decreased(p<0.05) in both the acute and chronic group. However, it was not statistically significant between the two groups. There was a statistically significant decrease(p<0.05) in the TMJ sound in the acute group after one week of Pumping treatment, but no change was notable in the chronic group and it was not statistically significant between the two groups. From the above results, we can conclude that Pumping into the upper joint cavity of patients having reducible disc displacement is effective in reducing clicking and pain. Therefore, it can be applied in diverse clinical fields.

• Journal of Animal Science and Technology
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• v.51 no.4
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• pp.337-342
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• 2009

The feasibility of reutilization of magnesium ammonium phosphate (MAP) or struvite slurry recovered from the process through microwave irradiation was studied in this experiment. For this purpose, 4 different operations were performed with or without Mg source addition and different levels of MAP recycled in a batch reactor. Dissolution rate of MAP, ${NH_4}^+$ elimination pattern and physicochemical changes of MAP during microwave irradiation were also studied. The result showed that only 33% orthophosphate ($PO_4-P$) and 27% $NH_4-N$ removal occurred without adding any external Mg source (run A), whereas 87% $PO_4-P$ and 40% $NH_4-N$ removed when 1.0 M ratio of $MgCl_2$ (run B) was added based on $PO_4-P$ in influent. Although the addition of 1.0 molar ratio of microwave irradiated MAP (Run C) removed lower $PO_4-P$ and $NH_4-N$ than 1.0 M $MgCl_2$ (run B), $PO_4-P$ removal was double when compared with no Mg addition (run A). Addition of half MAP and half $MgCl_2$ (run D) showed the similar removal efficiency (88% $PO_4-P$ and 35% $NH_4-N$) with sole $MgCl_2$ addition (run B). Based on these results, the reutilization of MAP irradiated by microwave would be a feasible way to enhance the removal efficiencies of N and P, as well as curtail the Mg chemical usage. Track study showed that $NH_4-N$ gradually increased at initial stage of microwave irradiation of MAP, and then started eliminating from liquor as temperature increased over $45^{\circ}C$. Dissolution rate of ${PO_4}^{-3}$ during microwave irradiation was proportional to the initial MAP concentration, having $0.0091x^{0.6373}$ mg/sec. It was found from the scanning electron microscope (SEM) study that physical structure of MAP crystal started breaking down into small cube granules within very short time by electromagnetic vibration force during microwave irradiation and then gradually melted down into solution.

• Journal of Dental Rehabilitation and Applied Science
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• v.25 no.1
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• pp.73-82
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• 2009

Injectable calcium phosphate cement (CPC) has been used as bone substitute successfully due to good biocompatibility and osteoconductivity. One of the important mechanical characteristics of CPC is flowablility, which can be evaluated by measuring rheological parameters. However, there have been few studies that measured rheological properties of CPC. The purpose of this study was to evaluate the effects of temperature and concentrations of 2 kinds of setting solutions, hydroxyprophyl methylcellulose (HPMC) and polyacrylic acid (PAA), on rheological properties of CPC. The CPC used was dicalcium phosphate dihydrate (DCPD). Rheological properties of CPC paste were measured using rheometer. The effect of concentrations of each solution (2% and 1% HPMC and 35% and 17.5% PAA) was evaluated. The effect of temperature ($25^{\circ}C$ and $37^{\circ}C$) on the rheological properties of CPC was also investigated. The statistical analysis was carried out with Mann-whitney test with Bonferronis collection. CPC with both setting solutions showed shear thinning behavior. Higher concentrations of setting solution (2% HPMC and 35% PAA) produced significantly higher viscosity than lower concentrations of setting solution (1% HPMC and 17.5% PAA). CPC with HPMC showed significantly higher viscosity at $37^{\circ}C$ that at $25^{\circ}C$. CPC with PAA showed lower viscosity at $37^{\circ}C$ than at $25^{\circ}C$, although the difference was not statistically significant. The results showed that CPC with HPMC or PAA solutions are pseudoplastic and the concentrations of setting solutions and temperature may have an effect on the rheological properties of CPC paste. These results showed that the flowability of injectable CPC could be improved by use of increasing frequency of oscillation. In clinical practice, the use of ultrasonic vibration would be helpful in application of injectable CPC. CPC with HPMC could be more easily applicated at $25^{\circ}C$ than $37^{\circ}C$. The use of lower concentrations of HPMC and PAA solution would be beneficial in terms of flowability.

• Cartoon and Animation Studies
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• s.46
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• pp.85-106
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• 2017

With the media's shift into the digital era in the 2000s, comic book publishers attempted a transition into the new medium by establishing a distribution structure using internet networks. But that effort shied from escaping the parallel-page reading structure of traditional comics. On the other hand, webtoons are showing divers changes by redesigning the structure of traditional sequential art media; they tend to separate and allot spaces according to the vertical scroll reading method of the internet browser and include animations, sound effects and background music. This trend is also in accordance with the preferences of modern readers. Modern society has complicated social structures with the development of various media; the public is therefore exposed to different stimuli and shows characteristics of differentiated perceptions. In other words, webtoons display more relevant and entertaining characteristics by inserting sounds and using moving texts and characters in specific frames, while traditional comics require an appreciation of withdrawal and immersion like other published media. Motions in webtoons are partially applied for dramatic tension or to create an effective expression of action. For example, hand-drawn animation is adopted to express motions by dividing motion images into many layers. Sounds are also utilized, such as background music with episode-related lyrics, melodies, ambient sounds and motion-related sound effects. In addition, webtoons provide readers with new amusement by giving tactile stimuli via the vibration of a smart phone. As stated above, the vertical direction, time-based nature of animation motions and tactile stimuli used in webtoons are differentiated from published comics. However, webtoons' utilization of innovative techniques hasn't yet reached its full potential. In addition to the fact that the software used for webtoon effects is operationally complex, this is a transitional phenomenon since there is still a lack of technical understanding of animation and sound application amongst the general public. For example, a sound might be programmed to play when a specific frame scrolls into view on the monitor, but the frame may be scrolled faster or slower than the author intended; in this case, sound can end before or after a reader sees the whole image. The motion of each frame is also programmed to start in a similar fashion. Therefore, a reader's scroll speed is related to the motion's speed. For this reason, motions might miss the intended timing and be unnatural because they are played out of context. Also, finished sound effects can disturb the concentration of readers. These problems come from a shortage of continuity; to solve these, naturally activated consecutive sounds or animations, like the simple rotation of joints when a character moves, is required.

• Restorative Dentistry and Endodontics
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• v.32 no.6
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• pp.522-529
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• 2007

The purpose of this study was to compare the apical leakage of the root canal filled with the System B and the EndoTwinn(the combined application of heat and ultrasonic vibration). Sixty extracted premolars with straight root were cleaned and shaped to size 35. Group SB was obturated using System B and Group ET was filled with EndoTwinn. A size 35 of 0.06 tapered gutta-percha and Adseal were used and the plugger which could be introduced to 4 mm short of working length was selected in the obturation procedure. As the positive control, Group PC was not filled. In Group SB, ET and PC, all external surfaces of each tooth were coated with nail varnish leaving only 1 mm area around the apical foramen. In the negative control of Group NSB and Group NET, all of external tooth surface including apical foramen was coated with the nail varnish. The specimens were immersed in methylene blue dye solution for 2 days. Then the specimens were sectioned at each 1 mm from apex to 5 mm level. The final score of one specimen was given by summing up of the points at all levels. The dye leakage of Group ET was significantly less than that observed in Group SB (p < 0.05). And the frequency of gutta-percha pulling out from root canal when the plugger was removed was more often with the System B than with EndoTwinn but there was no significant difference.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.12
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• pp.1098-1125
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• 2000

A review on the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering in 1998 and 1999 has been done. Focus has been put on current status of research in the aspect of heating, cooling, ventilation, sanitation and building environment. The conclusions are as follows. 1) A review of the recent studies on fluid flow, turbomachinery and pipe-network shows that many experimental investigations are conducted in applications of impingement jets. Researches on turbulent flows, pipe flows, pipe-networks are focused on analyses of practical systems and prediction of system performance. The results of noise reduction in the turbomachinery are also reported. 2) A review of the recent studies on heat transfer analysis and heat exchanger shows that there were many papers on the channel flow with the application to the design of heat exchanger in the heat transfer analysis. Various experimental and numerical papers on heat exchanger were also published, however, there were few papers available for the analysis of whole system including heat exchanger. 3) A review of the recent studies on heat pump system have focused on the multi-type system and the heat pump cycle to utilize treated sewage as the heat source. The defrosting and the frosting behaviors in the fin-tube heat exchanger is experimentally examined by several authors. Several papers on the ice storage cooling system are presented to show the dynamic simulation program and optimal operation conditions. The study on the micro heat pipes for the cooling of high power electronic components is carried out to examine the characteristics of heat and mass transfer processed. In addition to these, new type of separate thermosyphon is studied experimentally. 4) The recent studies on refrigeration/air conditioning system have focused on the system performance and efficiency for new alternative refrigerants. New systems operating with natural refrigerants are drawing lots of attention. In addition to these, evaporation and condensation heat transfer characteristics of traditional and new refrigerants are investigated for plain tubes and also for microfin tubes. Capillary tubes and orifice are main topics of research as expansion devices and studies on thermophysical properties of new refrigerants and refrigerant/oil mixtures are widely carried out. 5) A review of the recent studies on absorption cooling system shows that numerous experimental and analytical studies on the improvement of absorber performance have been presented. Dynamic analysis of compressor have been performed to understand its vibration characteristics. However research works on tow-phase flow and heat transfer, which could be encountered in the refrigeration system and various phase-change heat exchanger, were seemed to be insufficient. 6) A review of recent studies on duct system shows that the methods for circuit analysis, and flow balancing have been presented. Researches on ventilation are focused on the measurement of ventilation efficiency, and variation of ventilation efficiency with ventilation methods by numerous experimental and numerical studies. Furthermore, many studies have been conducted in real building in order to estimate indoor thermal environments. Many research works to get some information for cooling tower design have been performed but are insufficient. 7) A review on the recent studies on architectural thermal environment and building mechanical systems design shows that thermal comfort analysis is sitting environment, thermal performance analysis of Korean traditional building structures., and evaluation of building environmental load have been performed. However research works to improve the performance of mechanical system design and construction technology were seemed to be insufficient.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1983.05a
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• pp.11.2-11
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• 1983

Vocal nodules and polyps are much more frequent in singers, public speakers, teachers and actors. Voice trauma and voice misuse, at times associated with mild inflammatory reaction, appear to be important in their etiology. It is generally agreed that vocal cord nodules and polyps are inflammatory in nature and they arise in the subepithelial layer of loose connective tissue of the vocal cord. Since the junction of anterior and middle thirds of the membranous cord and has the greatest amplitude of vibration. This is the site of predilection for vocal cord nodules. The author performed laryngomicrosurgery for 70 cases of vocal nodules and polyps at Ewha Womans University Hospital during the period of 5 years. The result obtained were as follows ; 1) Surgical excision is not necessarily the best approach because vocal nodules in the early stages will resolve with the simplest voice therapy. 2) In children, surgery is rarely indicated because most nodules in children regress during adolescence. 3) For patients who use their voices professionally, voice therapy is indicated for three months. 4) If after three month of conservative treatment the cord lesion does not improve and the patient it still dissatisfied with his voice, laryngomicrosurgery can then be considered. 5) The small cuffed endotracheal tube in the interarytenoid space helps to keep the cords immobile and in an abducted position. 6) Removal of the nodule shoule be started by gentle retraction posteriorly and as soon as a tear appears anterior to the nodule. 7) On occasion it is preferable to start the dissection with a siccle knife while the nodule is held on the stretch. 8) Voice rest should be maintained for a week following which the free edges of the cords are usually healed.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1983.05a
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• pp.8.2-9
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• 1983

Recently, the laryngomicrosurgery has been done for the removal of benign laryngeal mass and for the improvement of voice. For the evaluation of the effect of the treatment, there must be any objective method such as aerodynamic study, vocal fold vibration study, acoustic analysis, psycho-acoustic evaluation and the neuro-muscular study. The authors evaluated the phoniatric effect of the laryngomicrosurgery for the patients of 15 laryngeal polyps and 9 laryngeal nodules, who received pre-op. and post-op. vocal function study from Jun. 1981 to Mar. 1983. The results obtained were as follows ; 1) The post-op. mean value of the maximum phonation time was increased 40 % in the unilateral polyps, 62 % in the bilateral nodules and 18 % in the unilateral nodules. 2) The post-op. mean value of the phonation quotient was decreased 25 % in comparison with pre-op. value in the case of the bilateral polyps, 26 % in the unilateral polyps, 55 % in the bilateral nodules and 12 % in the unilateral nodules. 3) The post-op. mean value of the mean air flow rate was decreased 27 % in comparison with the pre-op. value in the case of the bilateral polyps, 25 % in the unilateral polyps, 65 % in the bilateral nodules, 25 % in the unilateral nodules. 4) The glottic chink of the 10 cases of polyps among the 11 cases were disappeared, and the glottic chink of the 5 cases of nodules among 7 cases were also disappeared after surgery. 5) The pre-op. hoarseness of the 10 cases of polyps among the pre-op. hoarseness of the 11 cases of polyps were changed to clear and the 3 cases of nodules were also changed to clear.

• Journal of the Korean Vacuum Society
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• v.17 no.6
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• pp.538-543
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• 2008

Recently a nano-scale diamond is possible to manufacture forms of powder(below 100 nm) by new processing of explosion or deposition method. Using a sintering of nano-scale diamond is possible to manufacture of grinding tools. We have need of a processing development of coated uniformly inorganic to prevent an abnormal grain growth of nano-crystal and bonding obstacle caused by sintering process. This paper, in order to improve the sintering property of nano-scale diamond, we coated ZnO thin films(thickness: $20{\sim}30\;nm$) in a vacuum by ALD(atomic layer deposition) Economically, in order to deposit ZnO all over the surface of nano-scale diamond powder, we used a new modified fluidized bed processing replaced mechanical vibration effect or fluidized bed reactor which utilized diamond floating owing to pressure of pulse(or purge) processing after inserted diamond powders in quartz tube(L: 20 mm) then closed quartz tube by porosity glass filter. We deposited ZnO thin films by ALD in closed both sides of quartz tube by porosity glass filter by ALD(precursor: DEZn($C_4H_{10}Zn$), reaction gas: $H_2O$) at $10^{\circ}C$(in canister). Processing procedure and injection time of reaction materials set up DEZn pulse-0.1 sec, DEZn purge-20 sec, $H_2O$ pulse-0.1 sec, $H_2O$ purge-40 sec and we put in operation repetitive 100 cycles(1 cycle is 4 steps) We confirmed microstructure of diamond powder and diamond powder doped ZnO thin film by TEM(transmission electron microscope) Through TEM analysis, we confirmed that diamond powder diameter was some $70{\sim}120\;nm$ and shape was tetragonal, hexagonal, etc before ALD. We confirmed that diameter of diamond powders doped ZnO thin film was some $70{\sim}120\;nm$ and uniform ZnO(thickness: $20{\sim}30\;nm$) thin film was successfully deposited on diamond powder surface according to brightness difference between diamond powder and ZnO.