• Korean Journal of Environment and Ecology
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• v.15 no.4
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• pp.379-393
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• 2002

Thirty-six plots (each size 100m2) have been set up and surveyed to investigate the plant community structure and the ecological density of Pinus densiflora for. eracta(Chunyang-type) community in Seobyeok-ri, Chungyang-myeon, bonghwa-gun, Kyeongsangbuk-do. Four communities, Community I (large DBH class), Community II (large DBH class), Community III (middle DBH class), Community IV(small DBH class), were classified into by mean DBH and mean height. Pinus densiflora for. eracta dominate in canopy layer, Fraxinus sieboldiana and Quercus mongolica dominate in understory layer, Rhododendron Schlippenbachii and R. mucronulatum dominate in shrub layer. It turned out that thefour communiteis had low species diversity(0.4320~0.9487; unit: 400$m^2$) and high similarity. By the result of ecological density analysis. the mean basal area was proportionated to mean DBH (cm) size. By the result of simple regression analysis between mean DBH(cm), mean distance(m), and the number of individual were as follow: Ecological distance(m) = 0.0934$\times$ DBH(cm) +0.6117, Number of individual=242.47$\times$ DBH(cm)$^{-1.009}$, Ecological distance=9.643$\times$No. of individua $l^{-0.7016}$. In addition to four communities were suitable to the growth of Tricholoma matsutake because average species were about 30~50 years old, litter layer was 0.5~2.5cm and the ratio of coverage shrub was 20% .

• Journal of Mechanical Science and Technology
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• v.16 no.12
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• pp.1693-1701
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• 2002

The intermittent spray characteristics of a multi-hole and a single-hole diesel nozzle were experimentally investigated. The hole number of the multi-hole nozzle was 5, and the hole diameter of the 5-hole and the single-hole nozzle was the same as d$\_$n/=0.32 ㎜ with the constant hole length to diameter ratio(l$\_$n//d$\_$n/=2.81). The droplet diameters of the spray, including the time-resolved droplet diameter, SMD (Sauter mean diameter) and AMD (arithmetic mean diameter) , injected intermittently from the two nozzles into the still ambient were measured by using a 2-D PDPA (phase Doppler particle analyzer). Through the time-resolved evolutions of the droplet diameter, it was found that the structure of the multi-hole and the single-hole nozzle spray consisted of the three main parts : (a) the leading edge affected by surrounding air. and composed of small droplets; (b) the central part surrounded by the leading edge and mixing flow region and scarcely affected by the resistance of air, (c) the trailing edge formed by the passage of the central part. The SMD decreases gradually with the increase in the radial distance, and the constant value is obtained at the outer region of the radial distance (normalized by hole diameter) of 7-8 and 6 for the 5-hole and single-hole nozzle, respectively. The SMD along the centerline of the spray decrease shapely with the increase in the axial distance after showing the maximum value near the nozzle tip. The SMD remains the constant value near the axial distance(normalized by hole diameter) of 150 and 180 for the 5-hole and the single-hole nozzle, respectively.

• Journal of Dental Rehabilitation and Applied Science
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• v.23 no.3
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• pp.197-203
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• 2007

Statement of problem: It is very important to establish the suitable position for artificial maxillary anterior teeth and the orientation of occlusal plane in fabrication of the complete dentures. Incisive papilla has been considered the most useful anatomic landmark in the arranging of a maxillary anterior artificial teeth. Purpose: To determine correct position of upper anterior artificial teeth in complete denture patients, relationship of incisive papilla, intercanine line, occlusal plane were evaluated in Korean adults. Materials and Method: Maxillary casts were made in 60 Korean dentate subjects. Each cast was mounted in Hanau modular articulator using Hanau spring bow. Then, anatomic landmarks were determined in each cast. Distance from central incisor to incisive papilla, distance from incisive papilla to intercanine line and discrepancies between frankfurt plane and occlusal plane were measured and analysed. Results: 1. The mean distance between the posterior point of incisive papilla and the incisal edge of central incisor was 11.20 mm (in male 11.77 mm, in female 10.55 mm) and there was no significant difference in measured values between male and female 2. The mean distance between the posterior point of incisive papilla and intercanine line was 2.52 mm (Male 2.57 mm, Female 2.35 mm) and there were no significant differencies in measured values between male and female 3. The mean discripancy between the Frankfurt plane and the occlusal plane were 9. 75 degree (Male 9.81 degree, Female 9.55 degree), and there was no significant difference in measured values between left and right sides.

• Physical Therapy Korea
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• v.15 no.3
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• pp.44-52
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• 2008

The purpose of this study was to investigate the effects of different objects and target location of dominant hand on the non-dominant hand movement kinematics in a bimanual reaching task. Fifteen right-handed volunteers were asked to reach from same starting point to the different target point of right and left hand with grasping the objects of different size. Independent variables were 1) three different object types (small mug cup, name pen, and PET bottle), and 2) three different target locations (shorter distance, same distance, and longer distance than the non-dominant hand) of the dominant hand. Dependent variables were movement time (MT), movement distance (MD), movement mean velocity ($MV_{mean}$), and movement peak velocity ($MV_{peak}$) of the non-dominant hand. Repeated measures two-way analysis of variance (ANOVA) was used to test for differences in the non-dominant hand movement kinematics during bimanual reaching. The results of this study were as follows: 1) MT of the non-dominant hand was increased significantly when traveling with grasping the mug cup and reaching the far target location, and was decreased significantly when traveling with grasping the PET bottle and reaching the near target location of the dominant hand. 2) MD of the non-dominant hand was significantly increased during reaching the far target location, and significantly decreased during reaching the near target location with dominant hand. 3) $MV_{mean}$ of the non-dominant hand was increased significantly when traveling with grasping the PET bottle, and was decreased significantly when traveling with grasping the mug cup of the dominant hand. Therefore, it can be concluded that the changes of the ipsilateral hand movement have influence on coupling of the contralateral hand movement in bimanual reaching.

• International Journal of Computer Science & Network Security
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• v.21 no.9
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• pp.191-202
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• 2021

This research was conducted with the aim to appraise the level of satisfaction of students and faculty members with the services of the Deanship of e-Learning and Distance Education at Umm Al-Qura University. In addition, it investigated any differences arising between the evaluation of students and faculty members for these services owing to their gender..To achieve these goals, a descriptive analysis methodology was used in this research. The sample comprised 1357 students (704 male and 653 female) and 372 faculty members (208 male and 164 female) from Umm Al-Qura University in the academic year 2020-2021. To collect the requisite data, the study participants were asked to complete a 5-point Likert scale questionnaire, and the validity and reliability of the data were then assessed. The findings revealed the existence of a high level of satisfaction of students and faculty members with the services of Deanship of e-Learning and Distance Education at Umm Al-Qura University. There are no statistically significant differences between the mean scores of students (male/female) at Umm Al-Qura University in evaluating the said services. Furthermore, there are no statistically significant differences between the mean scores of faculty members (male/female) at Umm Al-Qura University in evaluating these. There exist statistically significant differences between the mean scores of faculty members and students in the evaluation of the services of the Deanship for the benefit of faculty members.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.15 no.3
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• pp.34-44
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• 2016

This study was initiated to evaluate the performance of methodologies to estimate the space mean speed(SMS) using the time mean speed(TMS) which was collected from the vehicle detection system(VDS) in expressways. To this end, the methodologies presented in prior studies were firstly summarized. It is very hard to achieve exact SMSs and TMSs due to mechanical and communication errors in the field. Thus, a microscopic traffic simulation model was utilized to evaluated the performance. As a result, the harmonic mean and volume-distance weighted harmonic mean were close to the SMS in the case in which the TMSs of individual vehicles were used. However, when the 30-second-interval aggregated TMS were used, the volume-distance weighted harmonic mean was outstanding. In this study, a radar detector was installed in the Joongbu expressway to collect the SMS. The trajectory of individual vehicles collected from the detector were used to calculate the SMS, which was compared with the estimates using other methodologies selected in this study. As a result, the volume-distance weighted mean was turned out to be close to the SMS. However, as the congestion becomes severe. the deviation between the two speed becomes bigger.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2006.10a
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• pp.86-96
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• 2006

To provide some ecological informations for protection and management of mixed heronries, their distribution, breeding species and individuals, and site characteristics that may be important to heron ecology were investigated in Jeollanam-do during 2005 breeding season. During the study, 17 mixed heronries, containing a total of six ardeid species were found. Of them, Great Egret(Egretta alba) and Grey Heron(Ardea cinerea) bred in most sites(both 92%) and were most numerous(36.3%, 31.0% respectively). Many of heronries(53.3%) were located within the bamboo forest. Other site characteristics were as follows: the mean area of heronry was $2346m^2$ with range of $500-7,000m^2$, the mean distance between nearest two heronies was 18.1km with range of 5.6-40.4km, the mean distance to nearest village was 297m with range of 10-2,000m, the mean gradient of the topography was $18^{\circ}$ with range of $2^{\circ}{\sim}40^{\circ}$, and 40.0% of heronries were located in the eastern slope.

• The Korean Journal of Pain
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• v.26 no.2
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• pp.130-134
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• 2013

Background: The aims of this study were to analyze the anatomic variations of supraorbital foramina/notches in Koreans and to compare the results with those of previous studies examining other races. We evaluated the three-dimensional computed tomography (3D-CT) images of human faces using multidetector computed tomography (MDCT). Methods: A total of 395 adults (232 men and 163 women) were enrolled and the 3D-CT images of their faces were reviewed in this study. In this study, the data from the images included the presence, shape, width and distance from the nasion to the supraorbital foramina/notches. ANOVA was used to assess the main effects of gender and side (right or left foramen/notch), and comparisons of the means were done by paired t-test. Results: The most common shapes in Koreans were a single notch (39.5%) on the right hand side and a single foramen (42.3%) on the left hand side. The incidence of a single foramen in Koreans was high compared to other races. The mean foramen diameter was $2.34{\pm}0.78$ mm, and the mean distance from the nasion was $27.19{\pm}4.03$ mm. The mean notch diameter was $3.37{\pm}1.71$ mm, and the mean distance from the nasion was $23.42{\pm}2.45$ mm. Conclusions: This is the first study on the variations of supraorbital foramina/notches in Koreans using 3D-CT images of faces. The anatomic characteristics of the supraorbital foramina/notch will help in performing nerve blocks and maxillofacial surgery.

• The Journal of Korean Academy of Prosthodontics
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• v.24 no.1
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• pp.17-26
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• 1986

The purpose of this study was to investigate true hinge axis location with different times (8:00-9:00 A.M.,2:00-3:00 P.M.) and with experienced and inexperienced groups. 25 subjects, 23-27 years of age , with functionally acceptable occlusion, and no clinical signs of temporomandibular joint dysfunction were participated in this study. In this study arbitrary hinge axis point was located 13 mm anterior to the posterior margin of the tragus on a line from the center of the tragus to the outer canthus of the eye and then the true hinge axis point was located with T.M.J. hinge axis locator. The discrepancies of distance and the direction between true hinge axis point and arbitrary hinge axis point were studied according to times and two groups. The results obtained were as follows : 1. The mean distance from arbitrary hinge axis point to the true hinge axis point on the right and left sides was as follows : Experienced group: linear distance: $1.228{\pm}3.145mm$, vertical distance: $-1.128{\pm}2.515mm$, horizontal distance: $-0.484{\pm}1.806mm$. Inexperience group: linear distance: $1.628{\pm}3.158mm$, vertical distance: $-1.169{\pm}2.090mm$, horizontal distance: $-1.133{\pm}2.367mm$. Horizontal distance between experienced and inexperienced groups was significant statistically. (P<0.1) 2. True hinge axis points located within 5 mm of arbitrary hinge axis point were 86.7% in the experienced group and 84% in the inexperienced group. 3. For experienced operator A with time, the mean distance from arbitrary hinge axis point to true hinge axis point was as follows: Horizontal distance: AM: $-0.613{\pm}1.966mm$, PM: $-0.860{\pm}2.156mm$. Vertical distance: AM: $-0.886{\pm}2.518mm$, PM : $-1.226{\pm}2.660mm$. True hinge axis points had tendency to be located posterior-inferiorly to tragus-canthus line in the afternoon than in the morning, but there was not significant statistically. (P>0.1)

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.2
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• pp.97-103
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• 2018

Purpose: The aim of this study was to evaluate the Bonwill triangle of Korean using the cone beam computerized tomography (Cone-beam CT). Materials and Methods: 120 Koreans (60 males and 60 females) who visited Daejeon Dental College Hospital of Wonkwang University and who underwent the Cone-beam CT were selected. The Cone-beam CT images were analysed with Invivo 5.1 (Anatomage, San Jose, USA). After reorientation of axis, the intercondylar distance was measured by clicking both middle points of condyle. And the condyle-incisor distance was measured by clicking the middle point of condyle and contact point of the mandibular central incisor's incisal edge. The collected data were analysed using the SPSS Version 23.0 (IBM Inc., Armonk, USA) and statistical significance was verified by gender using independent t-test. Results: The mean intercondylar distance of Korean was 105.9 mm, and the male (108.3 mm) was statistically significantly larger than the female (103.4 mm). The mean condyle-incisor distance of Korean was 105.2 mm, and the male (108.1 mm) was statistically significantly larger than the female (102.3 mm). Conclusion: The mean intercondylar distance of Korean in this study was 105.9 mm that was smaller than well-known 110 mm of Caucasian and the male was statistically significantly larger than the female. Within the limitations of this study, it would be necessary to use the articulator which can adjust the intercondylar distance according to the individual for prosthodontic treatment of Korean.