• 대한치과교정학회지
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• 제11권1호
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• pp.31-34
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• 1981

A study of a sample of 81 Korean adolescents was taken to determine the degree of correlation between mandibular anterior teeth size and the size of the canines and premolars. The correlation between the total mesiodistal width of the mandibular permanent incisors and that of maxillary or mandibular canine and first and second premolars was found to be 0.53 and 0.58, respectively. Further , regression constants were determined in an attempt to estimate the buccal segments from the mandibular incisors.

• Journal of Advanced Marine Engineering and Technology
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• 제27권7호
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• pp.826-831
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• 2003

The purpose of this study was to measure the surface tension of hard water through electro-magnetic field for investigating the effect of electro-magnetic water treatment. The maximum reduction of surface tension was 8% comparing to the no treatment case. When the flow velocity through the permanent magnetic device (PMD) was 6.3 m/s, sample of hard water had the minimum surface tension.

• 한국산림과학회지
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• 제97권5호
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• pp.501-507
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• 2008

The data of crown width with 4 directions, DBH, tree height, and coordinate for sample trees were collected from 30 permanent sample plots in secondary fore st of the Maoershan Experimental Forestry Farm, Northeast China. In this paper, the competition of individual trees in stand were discussed for secondary forest by using iterative Hegyi competition index and crown overlap index that represented the competitive and cooperative interactions among neighboring trees. Active competitors of subject tree in the competition zone were selected to calculate the iterative competition index. Using the results of crown classification based on the equal crown projection area, a new distance dependent competition index called crown overlap index (COI) was developed for secondary forest. The COI performed well in describing the crown competition rather than crown competition factor (CCF). The individual-based competition index discussed in this paper will provide more precise for developing individual tree growth models for secondary forest and it can also use to adjust the stand structure for spatial optimal management.

• Nuclear Engineering and Technology
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• 제56권7호
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• pp.2704-2710
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• 2024

Nuclear archaeology research provides scientific methods to reconstruct the operating histories of fissile material production facilities to account for past fissile material production. While it has typically focused on analyzing material in permanent reactor structures, spent fuel or high-level waste also hold information about the reactor operation. In this computational study, we explore a Bayesian inference framework for reconstructing the operational history from measurements of isotope ratios from a sample of nuclear waste. We investigate two different inference models. The first model discriminates between three potential reactors of origin (Magnox, PWR, and PHWR) while simultaneously reconstructing the fuel burnup, time since irradiation, initial enrichment, and average power density. The second model reconstructs the fuel burnup and time since irradiation of two batches of waste in a mixed sample. Each of the models is applied to a set of simulated test data, and the performance is evaluated by comparing the highest posterior density regions to the corresponding parameter values of the test dataset. Both models perform well on the simulated test cases, which highlights the potential of the Bayesian inference framework and opens up avenues for further investigation.

• The Journal of Asian Finance, Economics and Business
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• 제8권2호
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• pp.625-633
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• 2021

This study analyzes the impact of the reward variable on employees' performance through work motivation and employee engagement. This study's specific purpose is to investigate employee engagement's mediating role in the relationship between reward and employee performance. The sample of research is the employee at Sukorejo, Pasuruan Indonesia. The sample is permanent employees at manufacture corporate. The sample size is 150 employees of the total 759 workers through the calculation of the Slovin formula. Respondents in this study were employees with the criteria for having worked for at least last five years. The data obtained is in the form of answers from employees to the statements submitted. The data analysis was used structural equation modeling partial least square. To test the relationship between variables, it was equipped with a Sobel mediation test of statistics. SmartPLS 3.0 is used to help analyze the relationship between variables. The result shows that the reward does not have a direct influence on the performance of employees. However, it has a significant positive effect on the performance of employees through employee engagement. While working motivation variable does not have the role as a mediation variable related to the effect of reward on employee performance.

• Journal of Korean Dental Science
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• 제11권1호
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• pp.14-20
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• 2018

Purpose: The purpose of this study is to measure and compare the removal torques of different cements applied in attachments of zirconia restorations on titanium (Ti) abutments fitted with retrievable cement-type slot (RCS) on the lingual side for the better retrievablity by use of a slot driver. Materials and Methods: Three types of cements were used in the experiment: two permanent cements in $RelyX^{TM}$ U200 (RU) (3M ESPE) which is a resin cement and $FujiCem^{TM}$ (FC) (GC) which is a resin-modified glass ionomer cement, and a temporary cement in $Freegenol^{TM}$ temporary cement (TC) (GC). Measurements of removal torques were conducted as follows; an attached sample was fixed on the equipment customized for the experiment; a slot driver was connected to a MGT12 (Mark-10 Corp.), a torque measurement instrument; the sample had the driver fitted to its RCS and then was rotated until the it was removed; and finally, the maximum torque value was recorded. Result: As for the removal torque measurement results, the average values were $47.9{\pm}2.6Ncm$ for RU, $43.4{\pm}1.5Ncm$ for FC, and $20.9{\pm}1.0Ncm$ for TC. The statistical analysis using Kruskal-Wallis test yielded the significance probability of P<0.05 (P=0.002), which confirmed the presence of significant differences between the three groups. Conclusion: All three cements exhibit clinically acceptable levels of removal torque when applied to an upper zirconia implant restoration fitted with a lingual slot, with RU and FC, the two permanent cements, having the significantly higher values than that of TC, the temporary cement.

• Journal of Forest and Environmental Science
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• 제24권3호
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• pp.159-164
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• 2008

Forest inventory is a commercial term meaning the preparation of detailed descriptive list of articles with number, quantity and value of each item included. Forest inventory deals with the measurement of trees and stands, the estimation of their volume, growth prediction, biomass, carbon stocks and the description tree characteristics, as well as the land upon which they are growing. National Forest Inventory Center (NFIC) in Korea conducts national forest inventory every 5 years to obtain accurate baseline data for national forest policy. The permanent sample plot data used in were collected by NFI. The objective of this study was to develop methods for quantifying forest resources at national scale based on $5^{th}$ National Forest Inventory (NFI) data in Korea. Forest land area decreased from 6.44 to 6.38 million ha between 1997 and 2007, continuing a slight downward trend in area beginning in the late 1990s. However forest resources of the Korea have continued improving in general condition and quality, as measured by increased average size and volume of trees. Growing-stock volume of the Korea increased from 17 to 123.79 cubic meter per ha between 1976 and 2007. The biomass in Korea was estimated to be 153.81 tons per hectare and carbon stocks in Korea was estimated to be 84.36 tons per hectare by NFI data. This information is important for government officials, public administration, the private business sector, and the researcher. Forest Inventory should be implemented in a way to be able to monitor and assess the forests continuously.

• 대한소아치과학회지
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• 제32권4호
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• pp.693-702
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• 2005

치아의 정확한 맹출 시기와 그 순서는 어린이의 발육 성숙도의 지표로서 소아치과 임상 및 예방 교정치료에 있어서 매우 중요하다. 이에 $2001{\sim}2003$년에 연세대학교 치과대학병원 소아치과에 내원한 어린이 중 만 5세부터 만 14세까지의 남자 654명, 여자 542명, 총 1,196명의 자료를 수집하여 영구치의 맹출 시기 및 순서에 대한 연구 결과 다음과 같은 결론을 얻었다. 1. 상악 영구치의 맹출 시기는 중절치 남 만6.81세, 여 만6.78세, 측절치 남 만8.30세, 여 만7.98세, 견치 남 만10.28세, 여 만10.04세, 제1소구치 남 만9.74세, 여 만9.90세, 제2소구치 남 만10.87세, 여 만10.41세, 제1대구치 남 만6.25세, 여 만6.54세, 제2대구치 남 만12.21세, 여 만12.03세였다. 2. 하악 영구치의 맹출 시기는 중절치 남 만6.00세, 여 만6.06세, 측절치 남 만6.99세, 여 만6.74세, 견치 남 만9.83세 여 만9.17세, 제1소구치 남 만9.92세, 여 만9.75세, 제2소구치 남 만10.66세, 여 만10.39세, 제1대구치 남 만5.99세, 여 만5.75세, 제2대구치 남 만11.92세, 여 만12.17세였다. 3. 영구치의 맹출 순서는 상악에서 제1대구치, 중절치, 측절치, 제1소구치, 견치, 제2소구치, 제2대구치의 순이었고, 하악에서 제 1대구치, 중절치, 측절치, 견치, 제 1소구치, 제2소구치, 제2대구치의 순이었다.

• Journal of Magnetics
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• 제21권3호
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• pp.315-321
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• 2016

M-Zn (M = Sb, V, Nb) substituted M-type strontium hexaferrites were prepared by a ceramic method. The phase composition, morphology and magnetic properties were studied by x-ray diffractometry, scanning electron microscopy and vibrating sample magnetometry. Saturation magnetization increases with a substitution up to 75.0 emu/g (2.5 % higher compared to unsubstituted hexaferrite) and then decreases with a further substitution. A coercive field of substituted hexaferrite powders with highest saturation magnetization is more than 3 kOe. Substituted strontium hexaferrite powders prepared in this work are a rare example of high $M_S$ compositions without doping rare-earth elements and would be a promising candidate for a permanent magnet application.

• Journal of Power Electronics
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• 제8권4호
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• pp.354-362
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• 2008

This paper presents neural load torque compensation method which is composed of a deadbeat load torque observer and gains compensation by a parameter estimator. As a result, the response of the PMSM (permanent magnet synchronous motor) obtains better precision position control. To reduce the noise effect, the post-filter is implemented by a MA (moving average) process. The parameter compensator with an RLSM (recursive least square method) parameter estimator is adopted to increase the performance of the load torque observer and main controller. The parameter estimator is combined with a high performance neural load torque observer to resolve problems. The neural network is trained in online phases and it is composed by a feed forward recall and error back-propagation training. During normal operation, the input-output response is sampled and the weighting value is trained multi-times by the error back-propagation method at each sample period to accommodate the possible variations in the parameters or load torque. As a result, the proposed control system has a robust and precise system against load torque and parameter variation. Stability and usefulness are verified by computer simulation and experiment.