• Progress in Medical Physics
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• v.29 no.3
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• pp.92-100
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• 2018

The manufacturer of a linear accelerator (LINAC) has reported that the target melting phenomenon could be caused by a non-recommended output setting and the excessive use of monitor unit (MU) with intensity-modulated radiation therapy (IMRT). Due to these reasons, we observed an unexpected beam interruption during the treatment of a patient in our institution. The target status was inspected and a replacement of the target was determined. After the target replacement, the beam profile was adjusted to the machine commissioning beam data, and the absolute doses-to-water for 6 MV and 10 MV photon beams were calibrated according to American Association of Physicists in Medicine (AAPM) Task Group (TG)-51 protocol. To verify the beam data after target replacement, the beam flatness, symmetry, output factor, and percent depth dose (PDD) were measured and compared with the commissioning data. The difference between the referenced and measured data for flatness and symmetry exhibited a coincidence within 0.3% for both 6 MV and 10 MV, and the difference of the PDD at 10 cm depth ($PDD_{10}$) was also within 0.3% for both photon energies. Also, patient-specific quality assurances (QAs) were performed with gamma analysis using a 2-D diode and ion chamber array detector for eight patients. The average gamma passing rates for all patients for the relative dose distribution was $99.1%{\pm}1.0%$, and those for absolute dose distribution was $97.2%{\pm}2.7%$, which means the gamma analysis results were all clinically acceptable. In this study, we recommend that the beam characteristics, such as beam profile, depth dose, and output factors, should be examined. Further, patient-specific QAs should be performed to verify the changes in the overall beam delivery system when a target replacement is inevitable; although it is more important to check the beam output in a daily routine.

• Korean Journal of Materials Research
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• v.6 no.8
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• pp.833-840
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• 1996

Diamond thin films were deposited on p-type (100) Si wafers using MPECVD. Prior to deposition, ultrasonic striking was done to improve density of nucleation sites with dimond powder of 40~$60\mu$m size. Then diamond thin films were deposited at $^900{\circ}C$, 40Torr and 1000W microwave power using ${CH}_{4}$ and ${H}_{2}$ gases. The purity, the morphology and the microstructur'e and microdefects of diamond thin films were characterized by Raman spectroscopy, SEM and TEM, repectively. In Raman spectroscopy the peaks of non-diamond phase increased as ${CH}_{4}$, concentration increased. In SEM, the morphology of diamond thin films varied from crystalline to cauliflower as ${CH}_{4}$, concentration increased. As ${CH}_{4}$ con centration increased, the density of defects increased, with most defects being {III} twin. ${MTP}_{5}$, were formed with five (II]) planes. As these (Ill) Planes were twinned, ${MTP}_{5}$, represented five-fold symmetry. ]n the interfaces, defects in diamond thin films fanned out from small regions implying nucleation sites.

• Bulletin of the Korean Chemical Society
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• v.15 no.1
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• pp.37-45
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• 1994

$(NH_4)_{4.5}[H_{3.5}{\alpha}-PtMo_6O_{24}]{\cdot}1.5\;H_2O(A),\;(NH_4)_4[H_4{\beta}-PtMo_6O_{24}]{\cdot}1.5\;H_2O(B),\;and\;K_{3.5}[H_{4.5}{\alpha}-PtMo_6O_{24}]{\cdot}3\;H_2O(C)$ have been synthesized and their molecular structures have been also determined by single-crystal X-ray diffraction technique. The space groups, unit cell parameters, and R factors are as follows: Compound A, monoclinic, $A_{2/a}$, a= 19.074 (3), b=21.490 (3), c=15.183 (2) ${\AA};\;{\beta}$=109.67 (1) ${\AA}$; z=8; R=0.075($IF_0I>4{\sigma}(IF_0I);$ Compound B, triclinic, P$bar{1}$, a=10.776 (2), b=15.174 (4), c=10.697 (3) ${\AA};\;{\alpha}$ =126.29 (2), ${\beta}$=111.55 (2), ${\gamma}$=93.18 (2) ${\AA}$; Z=2; R=0.046($IF_0I>3{\sigma}(IF_0I);$): Compound C, triclinic, Pl, a=12.426 (2), b=13.884 (2), c=10.089 (1) ${\AA}$; ${\alpha}$=102.59 (2), ${\beta}$=110.73 (1), ${\gamma}$=53.93 (1) ${\AA}$; Z=2; R=0.074 ($IF_0I>3{\sigma}(IF_0I)$. Compounds A and C contain the well-known Anderson structure (planar structure) heteropoly oxometalate having approximate $bar{3}_m(D_{3d})$ symmetry, while compound B contains the bent structure heteropoly oxometalate having appproximate $2_{mm}(C2_v)$ symmetry. The bent structure and the planar one are geometrical isomers. These compounds are rot only novel heteroply molybdates containing platinate(IV) but also the first example of geometrical isomerism in the hexamolybdoheteropoly oxometalates. That isomerization surprisingly occurred because of the change of only 0.5 non-acidic hydrogen atom attached to the polyanion such as $[H_{3.5}{\alpha} -PtMo_6O_{24}]^{4.5-}{\to}[H_4{\beta}-PtMo_6O_{24}]^{4-}{\to}[H_{4.5}{\alpha} -PtMo_6O_{24}]^{3.5-}$. It seems that the gradual protonation of the polyanion plays an important role in that isomerism. These heteropolyanions form dimers by strong hydrogen bonds between two heteropolyanions in the respective crystal system.

• Physical Therapy Korea
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• v.19 no.1
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• pp.28-36
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• 2012

This study used an unstable platform to change the support surface type and position of both lower limbs in order to determine changes in weight distribution and muscle including the vastus medialis, tibialis anterior, lateral hamstring, and lateral gastrocnemius of both lower limbs were evaluated during knee joint flexing and extending in a semi-squat movement in 32 hemiplegic patients. The support surface conditions applied to the lower limbs were divided into four categories: condition 1 had a stable platform for both lower limbs; condition 2 had an unstable platform for the non-hemiplegic side and a stable platform for the hemiplegic side; condition 3 had a stable platform for the non-hemiplegic side and an unstable platform for the hemiplegic side; and condition 4 had an unstable platform for both sides. The normalized EMG activity levels of muscles and weight bearing ratio of both sides in the four surface conditions were compared using repeated measures ANOVA. A significant increase was found in the weight support distribution for the hemiplegic side in flexing and extending sessions in condition 2 compared to the other conditions (p<.05). A statistically significant decrease in significant decrease in asymmetrical weight bearing in flexing and extending sessions was observed for condition 2 compared to the other conditions (p<.05). A similar significant decrease was found in differences in muscular activity for both lower limbs in condition 2 (p<.05). The muscular activity of the hemiplegic side, based on the support surface for each muscle showed a significantly greater increase in condition 2 (p<.05). An unstable platform for the non-hemiplegic side and a stable platform for the hemiplegic side therefore increased symmetry in terms of the weight support distribution rate and muscle activity of lower limbs in hemiplegic patients. The problem of postural control due to asymmetry in hemiplegic patients should be further studied with the aim of developing continuous effects of functional training based on the type and position of the support surfaces and functional improvement.

• The Research Journal of the Costume Culture
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• v.24 no.5
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• pp.626-641
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• 2016

Maximalism in modern fashion, which is contrary to the current fashion market that emphasizes functionality and practicality, is an important notion that has been expressed in a variety of ways through designer's unique sense with a mixture of experimental design. With such creative work that suits a trend in novel fashion design, Rei Kawakubo is a current representative of Comme des Garcons who has not only introduced deconstructivism and Japanese-style avant-garde to the fashion industry for the first time. Our research, thus, analyzed the characteristic of maximalism's expression based on the features represented in her collection. Firstly, Expandability is classified as a method of distorting parts of a body and a method of excessively overinflating the silhouette of clothing. Secondly, decorations are expressed in the other as blending different types of materials together. Thirdly, fantasy evokes a fresh and stimulating surreal sensation that may only be felt in an imagination by assigning supernatural and amusing expression to the garment. The forth, fusion refers to a creation of novelty from combining various types of elements and images. The fifth, experiment is unique trait that develops mysterious images, consisted of various details. The sixth, non-structure is different from an initial form of garment that maintains a bilateral symmetry. The importance of our research lies in proposing a fundamental data for development of creative design as well as in expanding a range of possible expression for maximalism, by analyzing the characteristics of maximalism seen in Rei Kawakubo's collection.

• Journal of Digital Contents Society
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• v.18 no.6
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• pp.1033-1040
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• 2017

Artists use artistic features of paintings to provide various emotions in paintings. These features may be simply color and texture, but they can move on to form a composition or a symmetry. Through these features, people can feel various emotions when enjoying paintings. Even though they are using these features, there are paintings that are not readily accessible to non-extractable experts. This is because the analysis of features is not intuitive. In this paper, we want to produce content that matches paintings and music. This helps user to understand painting easily with paintings and matched music.

• Journal of the Korean Ceramic Society
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• v.43 no.2 s.285
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• pp.136-141
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• 2006

The stabilizing behavior of heavy metals in the silicate glass containing Electric Arc Furnace dust (EAF dust) were studied by the Toxic Characterization Leaching Procedure (TCLP) test, and the change of crystalline phase and glass network structure were investigated as a function of EAF dust content added. The glass containing EAF dust of $30\;wt\%$ an oxygen/network former ratio(R) of $2\~3$ allowing a fairly stable network structure thus showed much lower heavy metal leaching concentration than that for containing EAF dust above $50\;wt\%$ at TCLP test. For the glass containing EAF dust $50\~60\;wt\%$, however, the R was over 3, which weakened the glass network structure and increased the heavy metals leachate. Adding the EAF dust to a glass decreased the degree of Si-O-Si symmetry and increased the number of non-bridging oxygen, which decreased the chemical durability of glasses. When the dust content in a glass was over $70\;wt\%$, the Zn and Fe ions reacted to form the spinel crystal rather than to bind to network structure of glass and leaching concentration of those ions from the specimen decreased, so the spinel phase could be attributed to lowering a heavy metal leaching.

• Physical Therapy Rehabilitation Science
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• v.4 no.2
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• pp.94-102
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• 2015

Objective: The purpose of this study is to investigate the effect of treadmill gait training with patellar taping on gait abilities in chronic stroke patients. Design: Randomized controlled trial. Methods: Thirty chronic stroke patients who have been diagnosed at least six months or before were recruited in Gyeongin Rehabilitation Center Hospital, located in Incheon. Patients who were enrolled in this study were randomized to experimental group (n=15) or control group (n=15). Treadmill with patella taping training group patients were applied with patellar taping when they were being trained on a treadmill. Control group patients were being trained on a treadmill without any kind of taping. Gait parameters were measured with a GAITRite$^{(R)}$ system which evaluated gait performances. Gait trainings were done for 30 min/day, 5 days/week, for 4 weeks. Results: After treadmill training, treadmill with patella taping training group showed a significant improvement in gait abilities, including velocity, cadence, paretic and non-paretic step length, and double support period (p<0.05). However, in general treadmill group, there were no significant differences in gait parameters except velocity and cadence. There was a significant difference in gait performance in the experimental group compared with the control group, except for the gait symmetry ratio (p<0.05). Conclusions: According to this result of this study, it seems that application of patellar taping in treadmill gait training for chronic stroke patients significantly improved gait abilities of these patients. Also, we can conclude that patella taping is thought to be useful in real clinical settings where there are many chronic patients who are in need of improvement in their gait abilities.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.9
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• pp.814-820
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• 2015

In this paper, A high selective dual-band bandpass filter was proposed using a dual-mode ring resonator with two short-circuited stubs. For dual-mode resonance, the ring resonator is directly connected with non-orthogonal feed-lines via coupling capacitors. Two short-circuited stubs which are unequal lengths are simultaneously placed at two corners along the two symmetry plane of the ring resonator in order to obtain dual-band responses. Because the feeding angle perturbated ring resonator of the proposed dual-band bandpass filter has the symmetrical structure, Even/Odd mode analysis can be well applied to extract the scattering parameters and transmission zero frequencies. The proposed dual-band bandpass filter was designed and fabricated for WLAN(Wireless Local Area Network) application of IEEE 802.11n standard. The measured results showed a good agreement with the simulation results, and it should be well applied not only for WLAN applications but also for any other communication systems.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.4
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• pp.769-774
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• 2006

This paper proposed a theoretic numerical modelling in control system design to analyze active suspension equipment by adopting minimum phase system theory. Recent in the field of suspension system design it is general to adopt active control scheme for stiffness and damping, and connection with other vehicle stability control equipment is also intricate, it is required for control system scheme to design more robust, higher response and precision control equipment. Transfer matrices of system with collocated sensors and actuators are symmetric. The symmetry is independent of the entities of mass, damping, or stiffness matrices, and is a non parametric nature. From this point of view, symmetric robust control system is analyzed and designed in this paper. Numerical example is shown for validity of robust control system design.