• The Journal of Korean Academy of Prosthodontics
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• v.31 no.4
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• pp.549-564
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• 1993

The purpose of this study was to research the condylar path and the anterior angle of glenoid fossae and classify the patterns of condylar path. Thirty male and female dental students with normal occlesion and masticatory system ranging in age from 21 to 30, without present symptoms and an)r history of TM joint disturbance, were selected for this study. Transcranial radiographs of TM joints under mandibular lateral movement were obtained. By the computer analysis on the radiographs, the angle of posterior slope of articular eminance, the sagittal condylar guidance angie, condylar movement patterns and the height of glenoid fossa was measured respectively, and studied their interrelationship comparatively. The results obtained were as follows : 1. The total distance of condylar movement on balancing side during mandibular lateral movement was 4.55mm for Lt. and 4.78mm for Rt. when mandible moved from C.R. to canine to canine relation and 7.86mm for the Lt. and 8.10mm for the Rt. when mandible moved from C.R. to 7.5mm. 2. The horizontal distance of condylar movement on balancing side during mandibular lateral movements was 3.16mm for the Lt. and 3.52mm for the Rt. when mandible moved from C.R. to canine to canine relation and 6.10mm for the Lt. and 6.30mm for the Rt. when mandible moved from C.R. to 7.5mm. 3. The sagittal condylar guidance angle on balancing side during mandibular lateral movements was $45.96^{\circ}$ for the Lt. and $43.22^{\circ}$ for the Rt. when mandible moved from C.R. from canine to canine relation and $41.14^{\circ}$ for the Lt. and $39.77^{\circ}$ for the Rt. when mandible moved from C.R. to 7.5mm. 4. The height of glenoid fossa was 8.23mm for the Lt. and 7.80mm for the Rt. and the angle of posterior slope of articular eminence was $38.30^{\circ}$ for the Lt. and $38.79^{\circ}$ for the Rt. by method-A and $55.61^{\circ}$ for the Lt. and $55.64^{\circ}$ for the Rt. by method-B. 5. The sequence of the frequency of condylar movement patterns on balancing side during mandibular lateral movement were concave type(30 cases), convex type(16 cases), reverse S shape curve(9 cases) and S shape curve(5 cases) when mandible moved from C.R. to canine to canine relation and concave type(27 cases), 5 shape curve(13 cases), convex type(11 cases) and reverse S shape curve(9 cases) when mandible moved from C.R. to 7.5mm.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.5
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• pp.809-815
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• 2020

A number of investigations and studies have been conducted in various fields regarding the sediment disasters of Mt. Woomyeon that occurred in July 2011. We collected and compared the topographic information of the general points where debris flows did not occur and the collapse points where the debris flow occurred in order to find out the characteristics of the collapse points in Woomyeon mountain. The collected topographic information is altitude, curvature, slope, aspect and TPI(topographic position index). As a result of comparison, there were relatively many collapse points at an altitude of 210m to 250m, and at a slope of 30° to 40°. In addition, the risk of collapse was low in a cell where the curvature was close to 0, and the risk was higher in concave terrain than in convex terrain. In the case of TPI, there was no statistical difference between the general points and the collapse points when the analysis radius was larger than 200m, and there was a correlation with the curvature when the analysis radius was smaller than 50m. In the case of debris flows that are affected by artificial structures or facilities, there is a possibility of disturbing the topographic analysis results. Therefore, if a research on debris flow is conducted on a mountain area that is heavily exposed to human activities, such as Woomyeon mountain, diversified factors must be considered to account for this impact.

• Journal of Korean Society of Forest Science
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• v.94 no.3 s.160
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• pp.129-134
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• 2005

Ths study was carried out to understand the geo-topographical characteristics of the landslide area (1.5 ha) in Maeri, Sangdong-myeon, Gimhaesi, Gyeongsangnam-do. The bedrock of the landslide area was diollites and the area in and around the upper slope with the scattered talus was composed of Masanam originated from Igneous rocks. The landslide occurred in 19th of April, 2004 and the amount of rainfall for 3 days before the landslide was 74mm. The landslide by land creeping in this area was mainly attributed to geo-topographical characteristics such as well developed colluvial and/or weathered soils, and land cutting in lower slope, although the landslide could be affected by the rainfall. The type of the landslide can be classified into the land creeping by concave colluvial soils.

• Journal of Korean Society of Forest Science
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• v.76 no.2
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• pp.161-168
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• 1987

Forest road (10 Km) constructed for the demonstrational purpose by Forest Work Training Center (F.T.C.) in 1984 was partly damaged through the roadside landside and ditch erosion by the typhoon in 1986. The causes were investigated to apply for protecting against the damage of mountain forest road. The damaging length caused by roadside landside is around 3% out of total length of 10 Km forest road, and mostly coming from the curve road filled up more than 10 m slope length on the concave mountain slope, partly from the foot of fillslope along the ever-following valley and from the both side of fillslope under the outlet of culvert with ever-flowing water. In case of ditch erosion, the big damage at V-type ditch is coming from the overflow of valley water flowing down along the inside slope. Other problem is also showing in the steepness of longitudial gradient, which is felt as a problem in road to be constructed under more than 10 persent of gradient. Other cause of ditch erosion is coming from the bury of sand basin (water collecting wall) by the debris in small diameter culvert zone, namely less than 400mm, in diameter and by the soil mass slumped down from steep wall slope. From above results the causes of F.T.C. model road damage is showing to come from no-following the general guide or little experience to protect against the forest road damage. When improved above mentioned mistakes, F.T.C. Method of mountain forest road type could be developed as a model of Mountain forest road.

• Journal of agriculture & life science
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• v.44 no.4
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• pp.9-20
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• 2010

This study was carried out to analyze the landslide characteristics and forest environment factors on the landslide area of Jeonlabuk-do province in korea. The results obtained from this study were summarized as follows; The total number of landslide occurrence was 182 areas. The average area of landslide scar was $1,859m^2$, average length of the landslides was 139m, average width was 13m. The landslides were highly occurred in igneous rock and coniferous. And also, slope gradient was $21{\sim}30^{\circ}$, aspect was NE, altitude was 401~500m, vertical and cross slope was concave (凹),stream order was 1 order, soil depth was 15m below, landslide type was linear, forest type was artificial. The relationship between landslide area and environmental factors was a positive correlation with cross slope (convex), position (upper), altitude (501m), forest type (coniferous), parent rock (sedimentary rock), D.B.H. (over 17cm), but was negative correlation with slope gradient ($31{\sim}40^{\circ}$), parent rock (igneous rock), D.B.H. (6~16cm).

• Journal of The Korean Astronomical Society
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• v.44 no.2
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• pp.49-58
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• 2011

We calculate the energy spectra of cosmic ray (CR) protons and electrons at a plane shock with quasi-parallel magnetic fields, using time-dependent, diffusive shock acceleration (DSA) simulations, including energy losses via synchrotron emission and Inverse Compton (IC) scattering. A thermal leakage injection model and a Bohm type diffusion coefficient are adopted. The electron spectrum at the shock becomes steady after the DSA energy gains balance the synchrotron/IC losses, and it cuts off at the equilibrium momentum $p_{eq}$. In the postshock region the cutoff momentum of the electron spectrum decreases with the distance from the shock due to the energy losses and the thickness of the spatial distribution of electrons scales as $p^{-1}$. Thus the slope of the downstream integrated spectrum steepens by one power of p for $p_{br}$ < p < $p_{eq}$, where the break momentum decreases with the shock age as $p_{br}\;{\infty}\;t^{-1}$. In a CR modified shock, both the proton and electron spectrum exhibit a concave curvature and deviate from the canonical test-particle power-law, and the upstream integrated electron spectrum could dominate over the downstream integrated spectrum near the cutoff momentum. Thus the spectral shape near the cutoff of X-ray synchrotron emission could reveal a signature of nonlinear DSA.

• Korean Journal of Optics and Photonics
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• v.3 no.4
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• pp.222-226
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• 1992

The lasing characteristics of a Nd:phosphate glass laser pumped by 514 nm of an $Ar^{+}$ laser has been investigated. The oscillator consists of a Nd:glass gain medium set at Brewster angle, and two concave mirrors, and a flat mirror with a reflectance of 98%. The $Ar^{+}$ laser pumping beam is focused longitudinally at the beam waist of laser mode for efficient pumping. The pumping beam is chopped at 100 Hz to reduce the heat loading to prevent the thermal damage of the gain medium by the latent heat from the absorbed pumping beam. The maximum laser output power of 70 mW at 1.5 W pumping and the threshold input power of 520 mW have been obtained.

• Journal of Korean Society of Forest Science
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• v.45 no.1
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• pp.11-25
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• 1979

There was much mass movement at many different mountain side of Peong Chang area in Kwangwon province by the influence of heavy rainfall through August/4 5, 1979. This study have done with the fact observed through the field survey and the information of the former researchers. The results are as follows; 1. Heavy rainfall area with more than 200mm per day and more than 60mm per hour as maximum rainfall during past 6 years, are distributed in the western side of the connecting line through Hoeng Seong, Weonju, Yeongdong, Muju, Namweon and Suncheon, and of the southern sea side of KeongsangNam-do. The heavy rain fan reason in the above area seems to be influenced by the mouktam range and moving direction of depression. 2. Peak point of heavy rainfall distribution always happen during the night time and seems to cause directly mass movement and serious damage. 3. Soil mass movement in Peongchang break out from the course sandy loam soil of granite group and the clay soil of lime stone and shale. Earth have moved along the surface of both bedrock or also the hardpan in case of the lime stone area. 4. Infiltration seems to be rapid on the both bedrock soil, the former is by the soil texture and the latter is by the crumb structure, high humus content and dense root system in surface soil. 5. Topographic pattern of mass movement spot is mostly the concave slope at the valley head or at the upper part of middle slope which run-off can easily come together from the surrounding slope. Soil profile of mass movement spot has wet soil in the lime stone area and loose or deep soil in the granite area. 6. Dominant slope degree of the soil mass movement site has steep slope, mostly, more than 25 degree and slope position that start mass movement is mostly in the range of the middle slope line to ridge line. 7. Vegetation status of soil mass movement area are mostly fire field agriculture area, it's abandoned grass land, young plantation made on the fire field poor forest of the erosion control site and non forest land composed mainly grass and shrubs. Very rare earth sliding can be found in the big tree stands but mostly from the thin soil site on the un-weatherd bed rock. 8. Dangerous condition of soil mass movement and land sliding seems to be estimated by the several environmental factors, namely, vegetation cover, slope degree, slope shape and position, bed rock and soil profile characteristics etc. 9. House break down are mostly happen on the following site, namely, colluvial cone and fan, talus, foot area of concave slope and small terrace or colluvial soil between valley and at the small river side Dangerous house from mass movement could be interpreted by the aerial photo with reference of the surrounding site condition of house and village in the mountain area 10. As a counter plan for the prevention of mass movement damage the technics of it's risk diagnosis and the field survey should be done, and the mass movement control of prevention should be started with the goverment support as soon as possible. The precautionary measures of house and village protection from mass movement damage should be made and executed and considered the protecting forest making around the house and village. 11. Dangerous or safety of house and village from mass movement and flood damage will be indentified and informed to the village people of mountain area through the forest extension work. 12. Clear cutting activity on the steep granite site, fire field making on the steep slope, house or village construction on the dangerous site and fuel collection in the eroded forest or the steep forest land should be surely prohibited When making the management plan the mass movement, soil erosion and flood problem will be concidered and also included the prevention method of disaster.

• Journal of Korean Society of Forest Science
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• v.97 no.6
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• pp.656-660
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• 2008

This study is carried out to minimize the damage to the forest road when locating strip roads in the future for stability of timberland after afforestation by assessing the factors that affect the damage on the forest road surface and making appropriate constructing standards. Major factors that influence damage to the strip road surface were location, longitudinal gradients, soil types, cross-section shape in order of influence on damage. it is considered that structural road factors like longitudinal gradients, road width, location factors such as construction location, slope gradients and road material like soil types were greatly related to occurrence of road surface damage. Damage occurrences in the forest road were severe at the valley, longitudinal gradients of over 24%, weathered granite soil, concave of road position, road width of over 3.0 m. stability was high at longitudinal gradients of 4~24%, road width of under 3.0 m, ridge of road position, straight slope, soil materials. The evaluation table of damage possibility on forest road was manufactured by discriminant analysis using Quantification theory(II). The results showed that the discriminant ratios was 79.4% and this table was available for forest manager.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1210-1210
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• 2001

On farm analysis of protein, moisture and oil in cereals and oil seeds is quickly being adopted by Australian farmers. The benefits of being able to measure protein and oil in grains and oil seeds are several : $\square$ Optimize crop payments $\square$ Monitor effects of fertilization $\square$ Blend on farm to meet market requirements $\square$ Off farm marketing - sell crop with load by load analysis However farmers are not NIR spectroscopists and the process of calibrating instruments has to the duty of the supplier. With the potential number of On Farm analyser being in the thousands, then the task of calibrating each instrument would be impossible, let alone the problems encountered with updating calibrations from season to season. As such, NIR technology Australia has developed a mechanism for \ulcorner\ulcorner\ulcorner their range of Cropscan 2000G NIR analysers so that a single calibration can be transferred from the master instrument to every slave instrument. Whole grain analysis has been developed over the last 10 years using Near Infrared Transmission through a sample of grain with a pathlength varying from 5-30mm. A continuous spectrum from 800-1100nm is the optimal wavelength coverage fro these applications and a grating based spectrophotometer has proven to provide the best means of producing this spectrum. The most important aspect of standardizing NIB instruments is to duplicate the spectral information. The task is to align spectrum from the slave instruments to the master instrument in terms of wavelength positioning and then to adjust the spectral response at each wavelength in order that the slave instruments mimic the master instrument. The Cropscan 2000G and 2000B Whole Grain Analyser use flat field spectrographs to produce a spectrum from 720-1100nm and a silicon photodiode array detector to collect the spectrum at approximately 10nm intervals. The concave holographic gratings used in the flat field spectrographs are produced by a process of photo lithography. As such each grating is an exact replica of the original. To align wavelengths in these instruments, NIR wheat sample scanned on the master and the slave instruments provides three check points in the spectrum to make a more exact alignment. Once the wavelengths are matched then many samples of wheat, approximately 10, exhibiting absorbances from 2 to 4.5 Abu, are scanned on the master and then on each slave. Using a simple linear regression technique, a slope and bias adjustment is made for each pixel of the detector. This process corrects the spectral response at each wavelength so that the slave instruments produce the same spectra as the master instrument. It is important to use as broad a range of absorbances in the samples so that a good slope and bias estimate can be calculated. These Slope and Bias (S'||'&'||'B) factors are then downloaded into the slave instruments. Calibrations developed on the master instrument can then be downloaded onto the slave instruments and perform similarly to the master instrument. The data shown in this paper illustrates the process of calculating these S'||'&'||'B factors and the transfer of calibrations for wheat, barley and sorghum between several instruments.