• The Journal of the Korean dental association
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• v.51 no.4
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• pp.198-203
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• 2013

Nowadays, it seems like that the concept of the early loading protocol has been intruded between the concept of the immediate loading supported by advanced clinicians and the concept of the conventional loading supported by the prudent clinicians. In particular, the stability dip, which is found to occur usually at 4~6 weeks after dental implant placement because the decrease of the primary mechanical stability is not compensated by the increase of the secondary biologic stability, is frequently pointed out as one of the major causes of early loading failure. In this article, based on our recent clinical investigation about the crestal bone preservation effect of the early loaded NanoTite$^{TM}$ Tapered Certain Prevail$^{(R)}$ (Biomet 3i, USA), the concept of the early loading is revisited. In addition, various methods to overcome the stability dip are reviewed as the oral and maxillofacial surgeon's view point.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.5
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• pp.153-160
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• 2004

In this paper, we propose an efficient bit loading algorithm for IEEE 802.11a wireless LAN systems. While a conventional bit loading algorithm uses the SNR value of each subcarrier, it is very difficult to estimate the exact SNR value in wireless LAN systems due to randomness of AWGN. Therefore, in order to solve this problem our proposed algorithm uses the channel frequency response instead of the SNR of each subcarrier. Through simulation results, we can obtain the performance gain of 3.5∼8㏈ at PER of 10-2 with the proposed bit loading algorithm while the conventional one obtains the performance gain of 0.5∼5㏈ at the same conditions. Also, the increased data rate can be confirmed 63Mbps. After the logic synthesis using 0.3${\mu}{\textrm}{m}$ CMOS technology, the logic gate count for the processor with proposed algorithm can be reduced by 34% in comparison with the conventional one.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1992.04a
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• pp.364-368
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• 1992

The conventional loading process of workpieces for a CNC lathe is performaed either by human or by a general robot. It is not suitable for a general robot to load workpieces because of high price and inefficiency. Starting from the description of the environment around CNC lathes and the analysis ofloading process, we have developed the task-oriented loading manipulator. The characteristics of a loading manipulator are the following: to load/unload heavy workpieces, to decrease the whole porcess time. The air-chuck to load heavy workpiece has high clamping force and light weight. A loading manipulator has accomplished both the integration of independent automation techniques and cost-down effect of product. A loading manupulator developed in this project has been designed for general loading process. The loading manipulator is capable of carrying heavy payload with respect to weight of robot in short cycle time.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.281-286
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• 2005

The main objective of the research work presented in this article is to present a systematic approach for designing a multilayer feed-forward artificial neural network based self-tuning power system stabilizer (ST-ANNPSS). In order to suggest an approach for selecting the number of neurons in the hidden layer, the dynamic performance of the system with ST-ANNPSS is studied and hence compared with that of conventional PSS. Finally the effect of variation of loading condition and equivalent reactance, Xe is investigated on dynamic performance of the system with ST-ANNPSS. Investigations reveal that ANN with one hidden layer comprising nine neurons is adequate and sufficient for ST-ANNPSS. Studies show that the dynamic performance of STANNPSS is quite superior to that of conventional PSS for the loading condition different from the nominal. Also it is revealed that the performance of ST-ANNPSS is quite robust to a wide variation in loading condition.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.4A
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• pp.315-321
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• 2010

In Ad-hoc networks, centralized power control is not suitable due to the absence of base stations, which perform the power control operation in the network to optimize the system performance. Therefore, each node should perform power control algorithm distributedly instead of the centralized one. The conventional distributed power control algorithm does not consider the adaptive bit loading operation to change the MCS (modulation and coding scheme) according to the received SINR (signal to interference and noise ratio), which limits the system throughput. In this paper, we propose a novel distributed bit loading and power control algorithm, which considers the adaptive bit loading operation to increase total system throughput and decrease outage probability. Simulation results show that the proposed algorithm performs much better than the conventional algorithm.

• Journal of Environmental Health Sciences
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• v.17 no.2
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• pp.41-47
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• 1991

A study on the effects of volumetric loading rate, surface loading rate and hydraulic. retention time (HRT) for the anaerobic treatment was conducted with the anaerobic fixed-film process using synthetic wastewater at lower temperature than that of conventional anaerobic treatment. The results are as follows 1. Alkalinity and pH value decreased as the hydraulic retention time increased 2. Increase of the volumetric lodaing rate led to increasl of effluent COD concentration and decrease of COD removal efficiency. 3. The removed volumetric loading rate increased linearly according to the increase of the volumrtric loading rate. 4. Similarly, the linear increase of the removed surface loading rate was noticed with an increase of the surface loading rate.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.1
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• pp.1-9
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• 2000

This study was carried out to improve the opacity of printing paper. Conventional filler loading enhanced the opacity of paper, but subsequently caused reduction of paper strength of paper. We try to seek a new filler loading method so-called beater loading that enhances opacity of paper as well as sustained desire strength. In our experiment, comparing to direct loading method, the beater loading method enhanced 0.8% of opacity and 0.2% of brightness. This also decreased the rates of strength reduction of paper. Therefore, the results obtained in this study indicated that beater loading was a very effective method to improve the opacity of paper while not to decreased so much of paper strength.

• Proceedings of the KSR Conference
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• 2002.10b
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• pp.1029-1034
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• 2002

Object of this paper are numerical and experimental evaluation of Korean Standard Train Loading(L-loading scheme) with respect to UIC's and real train loading, quantitative formulation of the real train types in South Korea. These objects are require to changing environment of train operation, for example, high density traffic and gradual train speed increase. For the reasonable repair, reinforcement and rehabilitation of existing railway infrastructures, statistical analysis of the loading effect during the long term experiment in conventional lines have to conduct. Statistical quantitative formulation of the loading case need to consistency numerical evaluation of the railway safety. Hereafter, those results will be core technical data for the economy enhancement of international line construction. Further, these results are using to make track maintenance criterions for transcontinental, speed up railway and revision of standard train leading diagram.

• Steel and Composite Structures
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• v.9 no.1
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• pp.19-38
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• 2009

The present paper provides test data to evaluate the seismic performance of recycled aggregate concrete (RAC) filled steel square hollow section (SHS) beam-columns. Fifteen specimens, including 12 RAC filled steel tubular (RACFST) columns and 3 reference conventional concrete filled steel tubular (CFST) columns, were tested under reversed cyclic flexural loading while subjected to constant axially compressive load. The test parameters include: (1) axial load level (n), from 0.05 to 0.47; and (2) recycled coarse aggregate replacement ratio (r), from 0 to 50%. It was found that, generally, the seismic performance of RACFST columns was similar to that of the reference conventional CFST columns, and RACFST columns exhibited high levels of bearing capacity and ductility. Comparisons are made with predicted RACFST beam-column bearing capacities and flexural stiffness using current design codes. A theoretical model for conventional CFST beam-columns is employed in this paper for square RACFST beam-columns. The predicted load versus deformation hysteretic curves are found to exhibit satisfactory agreement with test results.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1629-1632
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• 2006

A novel column spacer with concaved top surface has been made through conventional photolithography process. The mechanical characteristics of this spacer were also investigated by using load-unload cycle test. According to the experimental results, the deformation ratio of this new designed spacer is larger than that of conventional column spacers about two times in the lower loading stage. At the higher loading stage there is no obviously difference in deformation ratio between the new designed spacer and the conventional spacer.