• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.23 no.2
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• pp.8-8
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• 1987

This paper describes on the distribution of the vibration and the noise produced on a skipjack pole and line training ship M/S Pusan 403 (243GT, 1,000ps) under the cruising or drifting condition. The vibration and the noise level were measured by use of protable vibration analyzer (B and K 3513) and sound level meter (B and K 2205), and so the vibration level was converted into dB unit. The check points were set through every decks and around important places of the ship. The results obtained can be summarized as follows: 1. The vibration and the noise level 1) On the main deck, both the vibration and the noise level were highest at the vertically above the main engine, whereas the vibration level was the lowest in the bow store and the noise level beneath the bridge. 2) Under cruising condition, the vibration level around the cylinder head of main engine, port side of the engine room, on the shaft tunnel was 80, 67, 65 dB and the noise level 104, 87, 86 dB, respectively. 3) The vibration level on the vertical line passing through the bridge was the highest at the orlop deck with 60 dB and the lowest on the bridge deck with 55 dB, whereas the noise level the highest at the compass deck with 75 dB and the lowest at the orlop deck with 53 dB. 4) The vibration and the noise level on the open decks were the highest with 65 dB and 84 dB on the boat deck, whereas the vibration level was the lowest at the lecture room with 51 dB and the noise level the lowest at the fore castle deck with 57 dB. 5) On the orlop decks, both the vibration and the noise level were the highest at the engine room with 65 dB and 85 dB, and the lowest at bow store with 54 dB and 52 dB, respectively. Comparing with the vibration level and the noise level, the vibration level was higher than the noise level in the bow part and it was contrary in the stern part of the ship. 2. Vibration analysis 1) The vibration displacement and the vibration velocity were the greatest at the cylinder head of main engine with 100μm and 11mm/sec, and were the smallest at the compass deck with 3μm and 0.07mm/sec. They were also attenuated rapidly around the frequency of 100Hz and over. 2) The vibration acceleration was the greatest at the cylinder head with the main frequency of 1KHz and the acceleration of 1.1mm/sec super(2), and the smallest at the compass deck with 30KHz and 0.05mm/sec super(2).

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.23 no.2
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• pp.54-60
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• 1987

This paper describes on the distribution of the vibration and the noise produced on a skipjack pole and line training ship M/S Pusan 403 (243GT, 1,000ps) under the cruising or drifting condition. The vibration and the noise level were measured by use of protable vibration analyzer (B and K 3513) and sound level meter (B and K 2205), and so the vibration level was converted into dB unit. The check points were set through every decks and around important places of the ship. The results obtained can be summarized as follows: 1. The vibration and the noise level 1) On the main deck, both the vibration and the noise level were highest at the vertically above the main engine, whereas the vibration level was the lowest in the bow store and the noise level beneath the bridge. 2) Under cruising condition, the vibration level around the cylinder head of main engine, port side of the engine room, on the shaft tunnel was 80, 67, 65 dB and the noise level 104, 87, 86 dB, respectively. 3) The vibration level on the vertical line passing through the bridge was the highest at the orlop deck with 60 dB and the lowest on the bridge deck with 55 dB, whereas the noise level the highest at the compass deck with 75 dB and the lowest at the orlop deck with 53 dB. 4) The vibration and the noise level on the open decks were the highest with 65 dB and 84 dB on the boat deck, whereas the vibration level was the lowest at the lecture room with 51 dB and the noise level the lowest at the fore castle deck with 57 dB. 5) On the orlop decks, both the vibration and the noise level were the highest at the engine room with 65 dB and 85 dB, and the lowest at bow store with 54 dB and 52 dB, respectively. Comparing with the vibration level and the noise level, the vibration level was higher than the noise level in the bow part and it was contrary in the stern part of the ship. 2. Vibration analysis 1) The vibration displacement and the vibration velocity were the greatest at the cylinder head of main engine with 100$\mu$m and 11mm/sec, and were the smallest at the compass deck with 3$\mu$m and 0.07mm/sec. They were also attenuated rapidly around the frequency of 100Hz and over. 2) The vibration acceleration was the greatest at the cylinder head with the main frequency of 1KHz and the acceleration of 1.1mm/sec super(2), and the smallest at the compass deck with 30KHz and 0.05mm/sec super(2).

• The korean journal of orthodontics
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• v.31 no.5 s.88
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• pp.479-487
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• 2001

The perception of facial esthetics is critically important to orthodontists. A viewpoint to facial esthetics is influenced by various factors and dependent on the perception of observer. The purpose of this study was to examine the differences regarding esthetic viewpoints among orthodontists, to identify attractive profiles preferred to orthodontists and to present the characteristic aspects of attractive profiles upon the degree of facial convexity. 35 persons whose faces were judged as attractive one by S orthodontists were selected out of 133 young Korean women. Soft tissue profiles Identified as a good-profile group were measured and analyzed. And then according to the facial convexity, good-profile group was subdivided to convex (G-Sn-Pg$9^{\circ}$) and straight (G-Sn-Pg<$9^{\circ}$) groups for the purpose of this study. There were statistically no significant differences regarding esthetic viewpoints among S orthodontists(p<0.05), even if there exists prevailing concept that the standard for facial esthetics is substantially subjective. N-Pg-Sn and N-Pg-Pn, measured for determining anteroposterior relationship of midfacial convexity, showed significant differences statistically between 2 subgroups (P

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.8
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• pp.253-263
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• 2013

Frequency Scanning Interferometry(FSI) system, one of the most promising optical surface measurement techniques, generally results in superior optical performance comparing with other 3-dimensional measuring methods as its hardware structure is fixed in operation and only the light frequency is scanned in a specific spectral band without vertical scanning of the target surface or the objective lens. FSI system collects a set of images of interference fringe by changing the frequency of light source. After that, it transforms intensity data of acquired image into frequency information, and calculates the height profile of target objects with the help of frequency analysis based on Fast Fourier Transform(FFT). However, it still suffers from optical noise on target surfaces and relatively long processing time due to the number of images acquired in frequency scanning phase. 1) a Polarization-based Frequency Scanning Interferometry(PFSI) is proposed for optical noise robustness. It consists of tunable laser for light source, ${\lambda}/4$ plate in front of reference mirror, ${\lambda}/4$ plate in front of target object, polarizing beam splitter, polarizer in front of image sensor, polarizer in front of the fiber coupled light source, ${\lambda}/2$ plate between PBS and polarizer of the light source. Using the proposed system, we can solve the problem of fringe image with low contrast by using polarization technique. Also, we can control light distribution of object beam and reference beam. 2) the signal processing acceleration method is proposed for PFSI, based on parallel processing architecture, which consists of parallel processing hardware and software such as Graphic Processing Unit(GPU) and Compute Unified Device Architecture(CUDA). As a result, the processing time reaches into tact time level of real-time processing. Finally, the proposed system is evaluated in terms of accuracy and processing speed through a series of experiment and the obtained results show the effectiveness of the proposed system and method.

• The korean journal of orthodontics
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• v.27 no.6 s.65
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• pp.963-978
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• 1997

Orthodontic patients are individuals that grow and develop ;therefore selection of the proper time for orthodontic treatment Is considered to be one of the most difficult and yet difficult factor.Since the development of cephalometric X-ray, amount and pattern of craniofacial growth change with aging could be predicted and became useful in the process of orthodontic treatment. The relationship between the mean values of cephalometric measurements and body height and weight was studied among the groups(boys and girls) of Korean children from the ages of 3-years to 12-years. 126 boys and 90 girls with no abnormality in growth and development and no history of orthodontic treatment from the ages of 3 years to 12 years were chosen as subjects: Cephalometric X-ray were taken for 2 years and hard tissue analysis based on Burstone's COGS, which was divided into measurements of 6 parts (Cranial base, Maxillar and Mandible, Vertical measurements, Horizontal measurements, Basal bone relationship, Dental measurements). The relationship between craniofacial growth and body height & weight was studied. The following conclusions were obtained : 1. The maximum growth in the measurements of cranial base, N-Ar(FH), N-Ba(FH) corresponded with the age with the maximum increasein body height & weight in both boys and girls. 2. Genial angle gradually decreased with aging in both boys and girls. 3. N-ANS(L) showed greater amount of growth than ANS-Me(L), and this had greater influence on facial profile. 4. $N-A-Pog^{\circ}$ decreased with aging, and mandibular growth exceeded maxillary growth in amount and rate. 5. Length of Y-axis increased, but Y-axis to FH plane remained constant. This show that mandible grows at a constant angulation to cranial base. 6. As Permanent teeth erupt, interincisal angle deceased.

• Journal of Korean Society of Forest Science
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• v.106 no.3
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• pp.275-287
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• 2017

The purpose of this study was to analyze forest vegetation type classification and relationships between the type and environment factor in Mt. Dutasan. Data were collected by total of forty six plots using Z-M phytosociological method from June to October, 2016, and analyzed by vegetation classification, canopy layer structure and relationships between vegetation unit and environment factor using coincidence methods. As a result of vegetation type classification, Quercus mongolica community group was classified at a top level of vegetation hierarchy that was classified into Rhododendron schlippenbachii community and Betula costata community. R. schlippenbachii community was divided into Lychnis cognata group and R. schlippenbachii typical group. L. cognata group was subdivided into Veratrum oxysepalum subgroup and L. cognata typical subgroup. B. costata community was divided into Fraxinus mandshurica group and Betula schmidtii group. F. mandshurica group was subdivided into Weigela subsessilis subgroup and Cimicifuga heracleifolia subgroup. Therefore the forest vegetation was composed of six vegetation units with two kinds of bisected species groups and fourteen species groups. As the result of an analysis of canopy layer structure, there were two kinds of structures with monotonous structures V. oxysepalum subgroup (vegetation units 1), L. cognata typical subgroup (vegetation units 2), W. subsessilis subgroup (vegetation units 4) and complicated structures R. schlippenbachii typical group (vegetation units 3), C. heracleifolia subgroup (vegetation units 5), Betula schmidtii group (vegetation units 6). The vertical layer structure of vegetation unit 5 was the most developed and vegetation unit 6 had the lowest coverage of herb layer. According to the correlation between vegetation unit and environmental factor, R. schlippenbachii community (vegetation units 1~3) and B. costata community (vegetation units 4~6) were classified based on 1,100 m of altitude, middle slope, twenty of slope degree, twenty percents of bare rock and thirty centimeters of DBH in tree layer. R. schlippenbachii community (vegetation units 1~3) showed positive correlation with altitude, topography and B. costata community (vegetation units 4~6) showed negative correlation tendency with them.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.4
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• pp.535-547
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• 2019

In this study, the heavy metal analysis in sediments (surface sediments, sediments cores and settling particles) from Shihwa Lake has been carried out to evaluate the changes of metal pollution levels in sediments after the operation of Tidal Power Plant (TPP). The average concentrations of metals in surface sediments sampled in 2015 were 8% (Cd)~31% (Zn, Hg) lower than in 2009 before TPP operation. Results of calculating the pollution load index (PLI) with 8 metals, the PLI value in 2015 showed a 18% decrease compared to 2009. However, Cu, Zn, Pb concentrations of surface sediments in 2015 at the upper region around industrial complex still exceeded the TEL (threshold effect level) values for sediment quality guideline in Korea. After the operation of TPP, the metal contaminated depths were increasing from 15 cm to 30 cm at S6 site and from 8 cm to 20 cm at S7 site, respectively. Our data showed that the mean concentration of heavy metals in core samples decreased but the contaminated depth increased. The average of the total sedimentation flux for particulate matter increased by 3.2 times from 32.5 g/㎡/d in 2009 to 103.5 g/㎡/d in 2015. This showed that the bottom sediments were resuspended by the operation of TPP, resulting in an increase of particulate matter in the water column. These results suggest that the sediments contaminated with heavy metals seem to be resuspended and relocated due to the water current caused by the operation of TPP. Cr, Cu, Zn, Pb and Cd were highly exceeding the TEL values in the upstream region and accumulated more than 40 cm of sediment depth, indicating that heavy metal contamination through industrial activity were still a serious environmental problem of Shihwa Lake. Although the metal pollution of Shihwa Lake has been slightly reduced, the contaminated sediments with heavy metals inside of Shihwa Lake might be discharged to outer sea after the resuspension by TPP operation. It is necessary for the advanced scientific approach and political decision to drastically reduce the heavy metal pollution of the study region.

• Korean Journal of Applied Biomechanics
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• v.12 no.2
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• pp.279-293
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• 2002

In the study the subjects who 10 university golfers act, and the kinetic factors were analyzed by the ground reaction system. the conclusion are as follows. 1) In the golf putting swing, the ground reaction factors of sagital plane in aspect are showen that the left and right foot sufficient difference, in the level of p <.05. 2) In the golf putting swing, the ground reaction factors of frontal plane in aspect is showen that the left foot has no significant difference in AD BS in the level of p < .05. In success, IP, FS. It can show significant difference. In addition, the right foot is shown the success, There is significant difference. 3) In the golf putting swing, the ground reaction factors of the vertical plane in aspect are shown that the left foot has no significant difference in BS, FS in the level p < .05. In success, AD, IP. It can show significant difference. In addition, the right foot is shown the success, There is significant difference. 4) In the golf putting swing, the ground reaction factors of torque in aspect are shown that the left foot had no significant difference in BS in the level p < .05. In success, AD, IP, FS. It can show significant difference. In addition, the right foot has no significant difference in IP in the level p < .05. AD, BS, FS. There is significant difference. The summarized conclusions are as follows. The first that the power of sagital plane needs the motion which can get the good power change in the stabilized pose. The second is that the small motion can make good putting in stabilized pose. The third is that the body weight move to the direction of the ball. The fourth is that the putting which looks perfect oscillation is good motion.

• Journal of the Korean earth science society
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• v.31 no.6
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• pp.600-607
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• 2010

In 2008, multiple episodes of large-scale transport of natural airborne particles and anthropogenically affected particles from different sources in the East Asian continent were identified in the National Oceanic and Atmospheric Administration (NOAA) satellite RGB-composite images and the mass concentrations of ground level particulate matters. To analyze the aerosol size distribution during the large-scale transport of atmospheric aerosols, both aerosol optical depth (AOD; proportional to the aerosol total loading in the vertical column) and fine aerosol weighting (FW; fractional contribution of fine aerosol to the total AOD) of Moderate resolution Imaging Spectroradiometer (MODIS) aerosol products were used over the East Asian region. The six episodes of massive natural airborne particles were observed at Cheongwon, originating from sandstorms in northern China, Mongolia and the loess plateau of China. The $PM_{10}$ and $PM_{2.5}$ stood at 70% and 16% of the total mass concentration of TSP, respectively. However, the mass concentration of $PM_{2.5}$ among TSP increased as high as 23% in the episode in which they were flowing in by way f the industrial area in east China. In the other five episodes of anthropogenically affected particles that flowed into the Korean Peninsula from east China, the mass concentrations of $PM_{10}$ and $PM_{2.5}$ among TSP reached 82% and 65%, respectively. The average AOD for the large-scale transport of anthropogenically affected particle episodes in the East Asian region was measured at $0.42{\pm}0.17$ compared with AOD ($0.36{\pm}0.13$) for the natural airborne particle episodes. Particularly, the regions covering east China, the Yellow Sea, the Korean Peninsula, and the east Korean sea were characterized by high levels of AOD. The average FW values observed during the event of anthropogenically affected aerosols ($0.63{\pm}0.16$) were moderately higher than those of natural airborne particles ($0.52{\pm}0.13$). This observation suggests that anthropogenically affected particles contribute greatly to the atmospheric aerosols in East Asia.

• 한국벤처창업학회:학술대회논문집
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• 2006.04a
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• pp.167-201
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• 2006

Korean corporations are transforming their vertical operational structure to a team-based structure to compete in the rapidly changing environment and for improved performance. However, a high percentage of the respondents in KBS said that despite the appearance of the present team structure, the organization operates much like a vertically-structured organization. This result can be attributed to the lack of study and implementation toward the goal of empowerment, the key variable for the success of the team-based structure. This study aims to provide policy suggestions on how to implement the process of empowerment, by investigating the conditions that hinder the process and the attitude of the KBS employees. For the cross-sectional study, this thesis examined the domestic and international references, conducted a survey of KBS employees, personal interviews and made direct observations. Approximately 1,200 copies of the Questionnaire were distributed and 474 were completed and returned. The analysis used SPSS 12.0 software to process the data collected from 460 respondents. For the longitudinal-study, six categories that were common to this study and "The Report of the Findings of KBS Employees' View of the Team Structure" were selected. The comparative study analyzed the changes in a ten-month period. The survey findings showed a decrease of 24.2%p in the number of responses expressing negative views of the team structure and a decrease of 1.29%p in the number of positive responses. The findings indicated a positive transformation illustrating employees' improved understanding and approval of the team structure. However, KBS must address the issue on an ongoing basis. It has been proven that the employee empowerment increases the productivity of the individual and the group. In order to boost the level of empowerment, the management must exercise new, innovative leadership and build trust between the managers and the employees first. Additional workload as a result of shirking at work places was prevalent throughout all divisions and ranks, according to the survey data. This outcome leads to the conclusion that the workload is not evenly distributed or shared. And the data also showed the employees do not trust the assessment and rewards system. More attention and consideration must be paid to the team size and job allocation in order to address this matter; the present assessment and rewards system need to be complemented. The type of leadership varies depending on the characteristics of the organization's structure and employees' disposition. KBS must develop and reform its own management, leadership style to suit the characteristics of individual teams. Finally, for a soft-landing of KBS team structure, in-house training and education are necessary.