• Journal of the Korean Chemical Society
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• v.7 no.2
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• pp.182-185
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• 1963

In the previous paper of the series of researches on the graphitic properties of anthracites, authors have already reported the results on the electrical specific resistance measurements for Korean anthracites in order to develope a simple methods which differentiate graphite from anthracite. In this paper, the X-ray diffraction method and oxidation have been applied and compared with the results which were obtained by the specific resistance measurements in the previous paper. It has been confirmed that there is a parallel relation between the value of specific resistance measurement and height of hexagonal peak by X-ray diffraction, but the color reaction due to graphitic acid by oxidation does not show any definite critical points between graphite and anthracite.

• Journal of Industrial Technology
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• v.18
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• pp.51-59
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• 1998

To flood forecastion, until now, Storage function method, Streamflow Synthesis and Reservoir Regulation, and HEC-1 model have been analysed generally in various definite simulation. Generally, Streamflow Synthesis and Reservoir Regulation and HEC-1 model are more delicacy and more excellent model than Storage function method in physically. But the resource huge for test of models. On the contrary, Storage function method has not only a few model various and data for decision but also has poor theory background in model excessively simpled water circulation about a basin. In this reason, this study is purpose to develop a statistical flood forecasting model that can forecast with accuracy variety of water height to Nak-Dong river vibration spots in flood with accumulated water resource.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.4
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• pp.563-575
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• 2003

The purpose of this study was to investigate differences in craniofacial characteristics of professional sportsmen who have practiced since their prepubertal periods. From the standardized lateral and P-A cephalograms of 137 sportsmen, 7 angular, 19 linear, 4 ratio, and 2 index measurements were measured and evaluated by means of statistical methods. The samples were divided into three groups: Group 1; ice hockey(n=17), foot-ball(n=27), basketball(n=16) Group 2; baseball(n=16), gymnastics(n=13), and Group 3; judo(n=18), ssireum(n=10), weight lift(n=20). The results were as follows: It seemed obvious that the cephalic indices of the 3 groups exhibited brachycephalic headform (Group 1; $0.85{\pm}0.04$, Group 2; $0.84{\pm}0.04$, Group 3; $0.83{\pm}0.06$) and there was no statistical difference among the groups (p>0.05). The facial indices of the Group 1 ($0.93{\pm}0.05$) and Group 2 ($0.93{\pm}0.04$) exhibited definite leptoprosopic facial forms while the Group 3 ($0.90{\pm}0.04$) showed more or less euryprosopic facial form, and there appeared significant difference between the Group 1 and 3 (p<0.05), and also between the Group 2 and 3 (p<0.05). There appeared strong relationships between the facial indices and the facial axis angle, mandibular plane angle, total craniofacial height, total facial height, upper anterior dental height, lower anterior dental height, mandibular length, lower anterior facial height ratio, and especially with lower anterior facial height (p<0.001). It seemed that most of the vertical facial measurements of the Group 1 and 2 appeared to be larger than those of the Group 3.

• Journal of Oral Medicine and Pain
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• v.34 no.2
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• pp.179-188
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• 2009

Aim of this study is to examine correlation between size of the coronal pulp cavity and chronological age in adult. Total 716 teeth (218 mandibular canines, 230 first premolars, 268 second premolars) free from pathologies and dental restorations were selected from 276 patients (111 males, 165 females), ranging from 20-69 years. Using periapical X-ray, the height (mm) of the crown (CH=coronal height) and the height (mm) of the coronal pulp cavity (CPCH=coronal pulp cavity height) of the teeth were measured. The tooth-coronal index (TCI) after Ikeda et al (Jpn. J. For. Med. 1985;39:244-250) was computed for each tooth and regressed on real age. With increasing age, the TCI was relatively decreased, indicating the reduction of length of the pulp chamber. Even reduction of the TCI with aging was found in combined group rather than in each sex and type of tooth separately. The most definite reduction was in canine of combined group. The correlation coefficient was strongest when measurement from canines of females (r2=0.247).

• Journal of Korean Neurosurgical Society
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• v.59 no.2
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• pp.129-136
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• 2016

Objective : The purpose of this study was to figure out the radiologic findings and risk factors related to adjacent segment degeneration (ASD) after anterior cervical discectomy and fusion (ACDF) using 3-year follow-up radiography, computed tomography (CT), and magnetic resonance image (MRI). Methods : A retrospective matched comparative study was performed for 64 patients who underwent single-level ACDF with a cage and plate. Radiologic parameters, including upper segment range of motion (USROM), lower segment range of motion (LSROM), upper segment disc height (UDH), and lower segment disc height (LDH), clinical outcomes assessed with neck and arm visual analogue scale (VAS), and risk factors were analyzed. Results : Patients were categorized into the ASD (32 patients) and non-ASD (32 patients) group. The decrease of UDH was significantly greater in the ASD group at each follow-up visit. At 36 months postoperatively, the difference for USROM value from the preoperative one significantly increased in the ASD group than non-ASD group. Preoperative other segment degeneration was significantly associated with the increased incidence of ASD at 36 months. However, pain intensity for the neck and arm was not significantly different between groups at any post-operative follow-up visit. Conclusion : The main factor affecting ASD is preoperative other segment degeneration out of the adjacent segment. In addition, patients over the age of 50 are at higher risk of developing ASD. Although there was definite radiologic degeneration in the ASD group, no significant difference was observed between the ASD and non-ASD groups in terms of the incidence of symptomatic disease.

• Korean Journal of Applied Biomechanics
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• v.16 no.4
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• pp.21-30
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• 2006

The purpose of the study is to search for the possibility of the application of kinematics analysis to physical education at schools and expand its scope of application. This study chose 9 college students majoring in physical education and classified them into type A group who can make the straight, vertical handstand, type B group whose waist is bent, type C group who cannot handstand completely. The center of mass, distance between hand and leg, and the angle and angular velocity of each joint were obtained. The result of this study is this. 1. The time for CM showed 6:4 for A group and 5:5 for B and C groups. The distance between hand and foot in the event 3 was 44% of the height for A group, and 41% for B and C groups. A Group showed the higher CM positional significant difference, it was vertically direction below the hip joint at front. For significant difference of the B Group showed horizontal and vertical velocity of the CM, the highest vertical was obtained in phase 3. The difference of angle of shoulder join in the flexion/extension was showed gradually extension event 2 and the height angular velocity was at phase 3 in the A group. 2 The analysis of the handstand motion revealed that the phase 3, but the maintenance of posture start part the handstand is also very important. Through these results, this study confirmed that the time for phase of the CM, horizontal and vertical positions, velocity, the distance between hands and foot, and the difference of the angle and angular velocity of hip joint and shoulder joint can be set as the variables of analysis. It was also definite cause that the handstand motions of college students majoring in physical education had many difference in performance.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.2
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• pp.231-237
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• 1986

Under the different conditions of planting density and nitrogen level with aromatic tobacco, some agronomic characters of tobacco like plant height, leaf size, LAI, yield and price were investigated in view of aroma volatile acid contents, the main compounds contributing to the aroma of oriental leaf tobacco. The closer a spacing interval became, the smaller the growth of plant and the leaf size with increment of yields, until about 22,000 plants per 10 are. But the leaf size became smaller without increment of yield when the planting density became more than 22,000 plants per 10 are. There were definite trends toward increase in leaf size, LAI and yield with increase in nitrogen rate. Correlation coefficient between aroma volatile and plant height, largest leaf length, one leaf area was -0.49, -0.49 and -0.47, respectively, showing significance at 1 % level. But LAI (r=-0.14) and dry weight of unit leaf area(r=0.25) was not observed to be significantly associated with aroma volatile, respectively. The results suggest that closer spacing is desirable for smaller leaves, higher contents of aroma volatile and for increased yield.

• Korean Journal of Acupuncture
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• v.18 no.1
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• pp.27-63
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• 2001

The phrase 'Gyeong Su' in the twelve gyeong su(經水) indicate twelve lower reaches of rivers and lakes which are located in the center of China. The reason of this chapter called 'twelve gyeong su(經水)' is that the ki(氣) circulation through twelve meridians in the human body is similar to constant flow of twelve lower reaches of rivers and lakes. This chapter is divided into five sub chapters, according to its contents as follows, Chapter 1 deals with the correlation between twelve gyeong su and twelve meridians, Chapter 2 deals with the correlation between universe and human body, Chapter 3 deals with the definite example of the correlation between human body and universe and Um-Yang(陰陽), Chapter 4 deals with most proper acupuncturing depth and remain time of acupuncture according to the theory of man, as a microcosm, is connected with the macrocosm(天人相應) and more or less of moxibustion amount, Chapter 5 deals with acupuncture application according to height, age, body shape of patients.

• Korean Journal of Agricultural Science
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• v.27 no.1
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• pp.5-12
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• 2000

The main purpose of this study is to obtain spatial image information toward forest thinning process in Larix forest stands. Thirteen different alternatives were simulated to visualize on the basis of actual thinning work photos. The options were illustrated as photos produced by photoshop program. Each alternatives were evaluated by forest visitor group with total 244 respondents after reliability test. Spatial images of 13 thinning photos were measured by 12 semantic differential scale as broad -narrow, ordered-tangled, friendly-unfriendly, monotonous-divers, dry-refreshing, relieved -stifling, healthy-sickly, uniform-scattered, dead-alive, opened-closed, bent-straight, and beautiful-ugly. In comparison with thinning stands and natural stands, thinning works were visual improvement effects of spatial images. Seemingly, this trend is due to definite form beauty, straight and clear length form of coniferous forest, As can be expected, slash and downwood were negatively related to improvement effects of spatial images. The 60% ratio of stem/ tree height and 450-950 trees/ha was positive in attraction of spatial images. Results indicate how to conduct forest thinning system for spatial images on Larix forest stands.

• Korean Institute of Interior Design Journal
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• no.32
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• pp.82-89
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• 2002

This study is focused on the chairs for students, especially, middle school students who grow rapidly compared with other group. We make a certain definite possibilities by the scientific and medical comparison of the approved chair with existing chair about the function of feet-height control & the application of the flexible back. The object of this test is middle & high school student (ratio of gender is the same) in Inchon. And the study types are two. One is to bring a matter and to suggest a design as alternative, the other is to verify propriety of the alternative. The major finding from the research are summarized as follows: 1) K·S standards for existing chairs are not proper to the growth rate of present juveniles, and they don't cope with proactive the discrepancy of growth pace. 2) Existing chairs have caused troubles by using only the fixed back of a chair. This troubles made bad influences on juveniles in a growth period. 3) Even existing chairs can adjust the back of a chair, they can be easily broken , and if they adjusted once, they can't be easily controled. Furthermore, it is Impossible to manage them because of the rust of control parts. 4) In the case of supplying the same sizes of them, juveniles who are different to growth rate respectively, can't accept the chairs. Even supplied adjustable chairs, they cant be ideal types of chairs in Open Classroom mode.