• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.20 no.2
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• pp.187-198
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• 1990

Examinations of the temporomandibular joints were performed on a 1.5 Tesla magnetic resonance (MR) system. An MR surface receiver coil 3 inch in diameter was placed on plastic frame, the patient's head being placed in the frame so that the coil was pressed against the temporal region. In taking advantage of the magnetic resonance imaging that has been studied briskly till now, author obtained the images of parasagittal and paracoronal planes about the temporomandibular joint by using MPGR (Multi-Planar Gradient Recalled), GRASS (Gradient Recalled Acquisition in the Steady State), and CSMEMP (Contiguous Slice Multiple Echo, Multi-Planar), that differ from the Spin Echo pulse sequence which the previous authors used. Five subjects with no symptoms of temporomandibular joint pain and dysfunction were studied. The plane images obtained by these methods were compared with those by Spin Echo pulse sequence. The results were as follows: 1. The optimal repetition times (TR) and echo times (TE) for T.M.J. image were; a. 400 msec and 18 msec in PMGR pulse sequence. b. 40 msec and 12 msec in GRASS pulse sequence. c. 700 msec and 30 msec in CSMEMP pulse sequence. d. 500 msec and 20 msec in Spin Echo pulse sequence. 2. When the MPGR pulse sequence was using, T2-weighted image was obtained in very short time. On the image of the paracoronal plane by GRASS pulse sequence, meniscus showed the moderate signal intensity, and the meniscus and its anteromedial, posterolateral attachments were observed definitely with gray color. 4. The signal intensity of Spin Echo pulse sequence was equal to that of CSMEMP pulse sequence, but the image by CSMEMP pulse sequence showed relatively lower level in its resolution.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1985-1988
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• 2013

Aim: To study any correlation of LKB1 expression with prognosis in hepatocellular carcinoma (HCC) cases. Methods: A total of 70 HCC patients and 20 primary intrahepatic stone patients in the first affiliated hospital of Wenzhou Medical College were enrolled in this study. LKB1 expression was detected by immunohistochemistry. Patients were followed-up and prognostic factors were evaluated. Result: LKB1 expression was decreased in the HCC samples. Loss of LKB1 expression in HCC was significantly related to histologic grade (P=0.010), vascular invasion (P=0.025) and TMN stage (P=0.011). Patients showing negative LKB1 expression had a significantly shorter disease-free and overall survival than those with positive expression (P = 0.001, P=0.000, respectively). Multivariate Cox regression analysis indicated that LKB1 expression level was an independent factor of survival (P = 0.033). Conclusion: HCC patients with decreased expression LKB1 have a poor prognosis. The loss of LKB1 expression is correlated with a lower survival rate.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.12 no.1
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• pp.3-24
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• 2001

All human being can't exist by oneself. That is, all human being depend on intimate attachment for their survival. Physical and psychological powers and control functions are prerequisites for one's survival and these serve important functions in interpersonal relationships. There are two kinds of powers and controls. One is positive power which helps one survive effectively. Another one is negative power which disturbs one's effective survival. Introspection is one of the positive power and most important process in understanding oneself and others. Thus, the purpose of this study is to elucidate the physical and psychological meaning of the characteristics of water and based on this meaning, to suggest one way of introspection. The authors reviewed the precept of water which is described in Bible and oriental classical books such as 'the Analects of Confuicus(論語)', 'Tao Te Ching(道德經)', 'Mencius(맹자)', 'Chronicle(史記)', 'The Doctrine of the Mean(中庸)', 'University(大學)'. The author also reviewed 'The History of Three Countries(삼국사기, 삼국유사)', 'The Precept of Religion', and 'the modern poems' which includes the symbolic meaning of water. The results are summarized as follows：1) The flow of water itself is the expression of introspection. Because, water does not flow without filling a puddle. 2) Water is the symbol of 'Immortality'. 3) Water symbolizes 'Modesty and Trust'. 4) Water is the symbol of 'Freedom from Greed'. 5) Water symbolizes 'Goodness and Beauty'. 6) Water symbolizes 'Naturality and Love'. Immortality, Modesty and Trust, Freedom from Greed, Goodness and Beauty, and Naturality and Love are eternal, universal values which all human should seek and achieve. By the process of introspection through the symbolic meaning of water, we can achieve these positive aspects of human mind and spirit.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.42 no.2
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• pp.23-28
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• 2005

This study was to suggest the propagation path loss and predictive model of propagation path analysis in order to apply the frequency in the millimeter-wave band to the real time inter-vehicle communication system. This study was to suppose the case of inter-vehicle communication on the one-way two-lanes road in the big cites with a lot of traffic jams in order to analyze the effect by the reflected wave of multipath. As a simulation of suggested model, it found out that the propagation path by the reflected wave was about 0.1[m]$\sim$5.1[m] longer than the one by the direct wave during the transmission of 100[m] wave direct path. Also, as a result of comparing the propagation path loss, the loss would be about -0.8[dB]$\sim$-4.2[dB] larger in case of wall reflection and -0.8[dB]$\sim$-1[dB] vehicle reflection. From the result above, this researcher found out that the path loss of reflected wave produced by the walls was about -3.2[dB] larger than the path loss produced by the adjacent vehicles.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.42 no.2
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• pp.1-6
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• 2005

Ryu et al. proposed a multiple target DOA tracking algorithm using a linear sensor array. In Ryu's algorithm first, the signal subspace is estimated using sensor output and the angular innovations of targets are extracted from the estimated signal subspace. Next, the DOA's of targets are tracked using the angular innovations as the inputs of Kalman filters. Ryu's algorithm has good features that it has no data association problem and is efficient. However, Ryu's algorithm can't be a lied to an arbitrarily shaped array because it was proposed using linear sensor array. Actually, when the sensor array is used in the various application fields, sensors have a position error. Therefore, the sensor array can be an arbitrarily shaped array. In this paper, we propose a multiple target DOA tracking algorithm applicable to an arbitrarily shaped array, and it sustains the good features of Ryu's algorithm.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.42 no.2
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• pp.7-14
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• 2005

This paper presents a method to reduce torque ripple of brushless DC motor by compensating phase delay due to winding inductance. For considering torque ripple comes from the phase winding inductance, torque equation of one phase is derived as Fourier series that is function of the delay. From the equation, also the resultant equation that the current delay is compensated is derived. It is validated that the compensated torque has a form of Fourier series for rectangular wave that is ideal torque, and torque ripple is reduced, consequently. Experimental method for the compensation is realized by replacing switching pattern of inverter by pattern of compensated rotor position. The effectiveness of the proposed method to reduce torque ripple has been demonstrated by the simulation and experimental results using 3 phase 4 pole brushless DC moor.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.91.1-91.1
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• 2014

IGRINS (the Immersion GRating INfrared Spectrometer) is a high resolution wide-band infrared spectrograph developed by the Korea Astronomy and Space Science Institute (KASI) and the University of Texas at Austin (UT). This spectrograph has H-band and K-band science cameras, both of which use Teledyne's $2.5{\mu}m$ cutoff $2k{\times}2k$ HgCdTe HAWAII-2RG CMOS science grade detectors. Teledyne's cryogenic SIDECAR ASIC boards and JADE2 USB interface cards were installed to control these detectors. We performed lab experiments and test observations to optimize and evaluate the detector systems of science cameras. In this presentation, we describe a process to optimize bias voltages and way to reduce pattern noise with reference pixel subtraction schemes. We also present measurements of the following properties under optimized settings of bias voltages at cryogenic temperature (70K): read noise, Fowler noise, dark current, and reference-level stability, full well depth, linearity and conversion gain.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.5
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• pp.687-697
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• 1999

A finite element analysis has been utilized to analyze stress and strain fields and design a new configuration in orthopedics and implant dentistry. Load transfer and stress analysis at implant bone interface are important factors from treatment planning to long term success. Bone configuration and quality are different according te anatomy of expecting implantation site. The purpose of this study was to compare the stress distribution in maxilla and mandible accord-ing to implant length and bone engagement types. A three dimensional axi-symmetric implant model(Nobel Biocare, Gothenburg, Sweden) with surrounding cortical and cancellous bone were designed to analyze the effects of bone engagement and implant length on stress distribution. ANSYS 5.5 finite element program was utilized as an interpreting toot. Three cases of unicortical anchorage model with 7, 10, 13 mm length and four cases of bicortical anchorage model with 5, 7, 10 and 13 mm length were compared both maxillary and mandibular single implant situation. Within the limits of study, following conclusions were drawn. 1. There is a difference in stress distribution according to cortical and cancellous bone thickness and shape. 2. Maximum stress was shown at the top of cortical bone area regardless of bone engagement types. 3. Bicortical engagement showed less stress accumulation when compared to unicortical case overall. 4. Longer the implant future length, less the stress on cortical bone area, however there is no difference in mandibular bicortical engagement case.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.17 no.4
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• pp.337-349
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• 1995

Periosteum in general is described as a specialized fibrous membrane of mesenchymal origin consisting of two basis layers : outer fibrous layer consists of irregularly arranged dense connective-tissue with fibroblasts, and inner osteogenic or cambial layer is composed of more loosely arranged fibers, greater vascularity and flatted spindle-shaped pre-osteoblasts. This periosteum may serve in controlling bone growth, especially mandibular growth has been emphasized. But, the periosteum enwrapping the facial skeleton have been studied for many years leaving a controversy in opinion regarding the function of these structures. We evaluated the bone formation activity of te periosteum in allogeneic bone grafts which bones are made of freeze-dried preparation preoperatively. We made the calvarial bone defects, 5 ${\times}$ 7mm sized, amd grafted with allogeneic bone in rats, which a half of specimens has dissected the overlying periosteum and a rest intacted. After bone grafting, we evaluated the capacity ofbone formation of periosteum, 1, 2, 4, 6, 8 weeks postoperatively. There are subtle differences of bone formation during early healing period after demineralized allogeneic bone grafting between control groups with periosteum and experimental groups without periosteum.

• Korean Journal of Oriental Medicine
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• v.3 no.1
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• pp.215-228
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• 1997

Extrapyramidal movement disorders are divided descriptively into hypokinesias(such as parkinsonism), characterized by poverty and slowness of movement : hyperkinesias(such as chorea, athetosis, dystonia, ballism, etc.), manifested by abnormal involuntary movement. Chorea refers to widespread arrythythmic movements of a forcible, rapid, jerky, restless type Choreic movements are noted for their irregularity and variability. They are generally continuous, may be simple or quite elaborate, and affect any part of the body. Dystonla refers to abnormally increased muscular tone that causes fixed abnormal postures. Some patients with dystonia also have shifting postures, resulting from irregular, forceful twisting movement that affect trunk and produce bizarre, grotesque movements and positions of the body. The most frequent and familiar type of focal dystonia is spasmodic torticollis. It consists of an involuntary turning of the head to one side - intermittent at first, then gradually worsening to the point of being more or loss continuous. The combination of blepharospasm and oromandibular dystonia is sometimes refered to as Meige's syndrome. We report two patients with dystonia and chorea in cerebral infarction at basal ganglia. We have experienced good improvement by the oriental medicine and acupuncture treatment.'rho acupuncture points of LI 4, ST 36, TE 3, GB 34, GB 41, LR 3, GB 39 were used. The therapies of herb-medicine were treated by Zibu-Ganshen(滋補肝腎), Huoxue-Xifeng-Tongluo(活血息風通絡).