• Journal of Biosystems Engineering
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• v.9 no.2
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• pp.27-36
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• 1984

This study was carried out to investigate the effects of the tilling depth, tilling travel speed and soil shear stress on the tilling load characteristics and power requirement for rotary tillers. The results obtained from the study are summarized as follows. 1. The average and maximum PTO torque increased as the tilling depth, tilling pitch and soil shear stress increased. A multiple linear regression equation to estimate the average PTO torque in terms of the above parameters was developed. 2. The ratios of maximum PTO torque to the average torque were in the range of 1.17 to 1.65 for the various tilling conditions tested. The variation in PTO torque increased greatly as the tilling pitch and soil shear stress increased, but decreased as the tilling depth increased. 3. Power requirement for the PTO shaft increased with the tilling depth, travel speed and soil shear stress, but decreased slightly as the tilling pitch increased. A multiple linear regression equation to estimate power requirement for the PTO shaft in terms of the above parameters was developed. 4. The specific power requirement for the rotary tiller was in the range of $0.008-0.015ps/cm^2$ for the various tilling conditons tested. The specific tilling capacity decreased as the tilling depth and soil shear stress increased, but increased with the tilling pitch. A multiple linear regression equation to estimate the specific tilling capacity in terms of the above parameters was developed.

• Journal of the Korean Vacuum Society
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• v.12 no.3
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• pp.162-167
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• 2003

To find the concentration according to the depth-direction of ions implanted in the sample, with sputtering of the sample surface, one needs the depth profiling of ion implanted in the sample. On measuring of depth profiling, the sputtering rate to affect depth direction, is calculated by SRIM simulation. When ion is implanted in the sample, the atomic density of the sample rises up a little, and it alters sputtering yield. This alteration then causes differences of sputtering rate to affect depth-direction, on measuring of depth profiling. With the usage of SRIM Monte Carlo simulation code, one calculates sputtering rate, with sputtering yield by the alteration of atomic density of the sample through ion implantation. As a result, it goes to prove that its difference affects depth distribution, on measuring of depth profiling.

• The Journal of the Acoustical Society of Korea
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• v.28 no.4
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• pp.318-327
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• 2009

In this paper, we propose a 3-D geometric localization method for near-field broadband source in shallow water environments. According to the waveguide invariant theory, slope of the interference pattern which is seen in a sensor spectrogram directly proportional to a range of the source. The relative ratio of the range between source and sensors was estimated by matching of two interference patterns in spectrogram. Then this ratio is applied to the Apollonius's circle which shows the locus of a source whose range ratio from two sensors is constant. Two Apollonius's circles from three sensors make the intersection point that means the horizontal range and the azimuth angle of the source. And this intersection point is constant with source depth. Therefore the source depth can be estimated using 3-D hyperboloid equation whose range difference from two sensors is constant. To evaluate a performance of the proposed localization algorithm, simulation is performed using acoustic propagation program and analysis of localization error is demonstrated. From simulation results, error estimate for range and depth is described within 50 m and 15 m respectively.

• Journal of Korean Foot and Ankle Society
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• v.12 no.2
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• pp.150-155
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• 2008

Purpose: This study was performed to compare the anatomic differences of the fibular incisura of the tibia between ankle fractures with and without syndesmotic injuries. Materials and Methods: 42 patients were involved in this study: Group I was composed with 14 cases of ankle fractures with syndesmotic injuries; Group II was composed with 14 cases of ankle fractures without syndesmotic injuries; Group III was composed with 14 cases of volunteers. The height averaged 170.1 cm (range, $159{\sim}181$ cm) in group I, 168.9 cm (range, $156{\sim}184$ cm) in group II, and 170.4 cm (range, $161{\sim}77$ cm) in group III. The mean height did not show a statistically significant difference between groups (p>0.05). All patients were taken axial computed tomography. The length of anterior and posterior facets, angle between anterior and posterior facet, and depth of the fibular incisura of the tibia were measured. Results: The mean length of the anterior facet was 11.5 mm (range, $9.2{\sim}15.7$ mm) in group I, 12.2 mm (range, $7.3{\sim}17.0$ mm) in group II, and 10.3 mm (range, $8.7{\sim}14.0$ mm) in group III (p>0.05). The mean length of the posterior facet was 12.3 mm (range, $9.0{\sim}14.5$ mm) in group I, 11.0 mm (range, $7.3{\sim}16.2$ mm) in group II, and 13.0 mm (range, $9.2{\sim}15.9$ mm) in group III (p>0.05). The mean angle between anterior and posterior facet was 139.1 degrees (range, $125.5{\sim}154.0$ degrees) in group I, 144.2 degrees (range, $134.7{\sim}152.6$ degrees) in group II, and 131.5 degrees (range, $117.6{\sim}144.4$ degrees) in group III (p<0.05). The mean depth of the fibular incisura of the tibia was 4.1 mm (range, $3.2{\sim}15.8$ mm) in group I, 4.6 mm (range, $3.1{\sim}7.1$ mm) in group II, and 3.1 mm (range, $1.5{\sim}4.0$ mm) in group III (p<0.05). Conclusion: There are some statistical differences of angle between anterior and posterior facet and depth of the fibular incisura of the tibia between ankle fractures with and without syndesmotic injuries.

• Journal of Korean society of Dental Hygiene
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• v.19 no.6
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• pp.907-918
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• 2019

Objectives: This qualitative research was conducted to clearly find and clinically understand dental hygienists' work experience in order to lay the legal foundation for their work range and safe execution. Methods: From March 1 to April 30, 2019, seven study participants were selected and participated in-depth interviews. Phenomenological research methodology was applied for intensive analysis. Results: They performed jobs that required no professionalism, such as dental assistance, except for scaling. Dental hygienists, nurses' aids, and dental technicians performed the same jobs regardless of difficulty level and legal work range. Dental hygienists failed to accurately recognize their legal work range. Since there was the wide gap between their legal work range and actual work range, it was necessary to expand the work range in line with actual conditions. Conclusions: Given the results, it is necessary to conduct in-depth discussions within the dental circle to make dental hygienists' work execution in line with reality by improving and discussing a legal system for job assignment and expansion of workers. Therefore, it is required to form a plan for the many jobs dental hygienists executed in a clinical setting.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.259-262
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• 2004

We propose novel schemes to enhance the expressible depth range of integral imaging. The implemented system that adopts the mirror barrier array has the compact thickness that is suitable for the practical use. With this system, the expressible depth range of the integral imaging is increased to over 120mm. The system that eliminates the mechanical motion also had been implemented. Experimental results are presented and the way to resolve the problem of occlusion is also discussed.

• Journal of Korean Vacuum Science & Technology
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• v.6 no.1
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• pp.8-11
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• 2002

Ni, Si and $SiO_2$ films were implanted by 350 keV B $i_{+}$ ions at room temperature with fluences of 1$\times$10$^{16}$ and 2$\times$10$^{16}$ ions/c $m^2$ The depth distributions of implanted B $i^{+}$ ions in Ni, Si and $SiO_2$ films were by investigated by Rutherford backscattering. The results show that the depth distributions of implanted B $i^{+}$ ions into Ni, Si and $SiO_2$ films have obeyed nearly Gaussian distributions. The maximum difference between experimental and calculated values is less than 18 % for mean projected range. Experimental range straggling deviated significantly from calculated value. The possible reasons are discussed.sed.d.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.746-752
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• 2000

A study on discharge characteristics of a rotating discharge hole is very important to enhance the performance of an induction motor which have external forced cooling system. The discharge characteristics of rotating discharge holes are influenced by rotating speed, length-to-diameter ratio, inlet shape of rotor holes, etc. An experimental study on the effect of chamfered inlet edge of rotor inlet part with various depth-to-diameter and inlet chamfered edge angle is conducted. Depth-to-diameter ratios range from 0 to 0.5 and inlet chamfered edge angle range from 0 to 60. As a result, there is an optimal design point of inlet chamfered edge depth. And the inlet edge angle far maximum discharge coefficient is influenced mainly by the rotating speed of discharge holes.

• Journal of Information Processing Systems
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• v.14 no.4
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• pp.877-891
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• 2018

In this paper, we propose a novel algorithm for rendering motion-blurred shadows utilizing a depth-time ranges shadow map. First, we render a scene from a light source to generate a shadow map. For each pixel in the shadow map, we store a list of depth-time ranges. Each range has two points defining a period where a particular geometry was visible to the light source and two distances from the light. Next, we render the scene from the camera to perform shadow tests. With the depths and times of each range, we can easily sample the shadow map at a particular receiver and time. Our algorithm runs entirely on GPUs and solves various problems encountered by previous approaches.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.9 s.186
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• pp.111-118
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• 2006

A hybrid focus method with multiple laser slits is newly proposed for the measurement of surface morphology with depth discontinuity, and it is based on the integration of DFB and DFF. Rough depth information is estimated through calibration tables which are constructed by DFD with multiple laser slits, and then DFF is applied to only each specific depth range using the rough depth information resulting from DFD. The proposed hybrid method gives more accurate results than DFD and DFF, and faster measurement than DFF in the vicinity of depth discontinuity Its performance is verified through experiments of calibration blocks with sharp depth discontinuity.