• Journal of Industrial Technology
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• v.20 no.A
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• pp.101-111
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• 2000

This research is results of experimental and numerical works on characteristic of strength increase and bearing capacity in dredged and reclaimed soil due to desiccation shrinkage. For a soil sampled from southern coastal area in Korea, basic soil property tests and standard consolidation test with falling head permeability tests were carried out to obtain consolidational characteristics of soil. Double cone penetration test, laboratory vane test and unconfined compression test were also performed to investigate the change of shear strength with degree of desiccation. Model tests were performed in 1G environment and 30G level artificially accelerated condition by using the centrifuge model test facilities to investigate the bearing capacity of desiccated ground. Test results were analyzed by using the theoretical and load-settlement characteristics method proposed by Meyehof & Hanna(1978). On the other hands, the numerical technique, using the finite strain consolidation theory considering the effect of desiccation was used to estimate the appropriate time of using heavy construction equipments in field with respect to strength increase due to desiccation.

• Geotechnical Engineering
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• v.14 no.4
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• pp.117-128
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• 1998

Solid mattress foundation using geogrid has often been used on soft grounds to increase the bearing capacity, and its effect has received much recognition. Geogrid-mattress system is the method of construction which increases the bearing capacity and the effect of controlling settlement by dispersing load to wider foundation through its stiffness. But ifs mechanism has not been examined exactly yet. considered to be influential factors in the experiments. As a result of the experiments, the characteristic of dispersing stress under mattress foundations was understood and the way of calculating the bearing capacity in designing the mattress foundations was suggested.

• The Journal of Korean Physical Therapy
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• v.8 no.1
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• pp.1-14
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• 1996

The present case study has a object to investigate the changes in locomotion patterns of infant with athetoid cerebral palsy would be occured by the program when it is applied with upper extremity weight bearing. The subject has been limited to one infant over one year of age, selected from the patients in the physical therapy clinic, Rehabilitation Center, Taegu University. Subject is normal in the visual and auditory sense, but he is unable to walk on his own Subject weighted 2.9kg at birth and underwent severe postnatal kernicterus, always on the baby-walker at homo. He disliked supine position characteristic in moving in athetoid type before he was under the program. The program was applied 7 months. Each session of the program is composed of 7 stages : (1) prebriefing between the therapist and the parents (2) pretherapy amusement time of the infant (3) warming-up (4) upper extremity weight bearing (5) cooling-down (6) post-therapy amusement time (7) postbriefing. The locomotion of the subject is proved to be influenced by the program. He showed a leftward circular movement as a result of the exercise, reducing the involuntary movement of his head when he was positioned for crawling. Later he proceeded to develop into creeping, crawling, kneeling and finally cruising. In conclusion, it appeared evident that the locomotive abilities of the subject is improved by the program explored in this study. The higher locomotive patterns could be achieved such as crawling, sitting, kneeling and cruising wich enable the upper extremities weight bearing.

• Smart Structures and Systems
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• v.29 no.3
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• pp.513-522
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• 2022

Due to the importance of accurate analysis of bearing capacity in civil engineering projects, this paper studies the efficiency of two novel metaheuristic-based models for this objective. To this end, black hole algorithm (BHA) and multi-verse optimizer (MVO) are synthesized with an artificial neural network (ANN) to build the proposed hybrid models. Based on the settlement of a two-layered soil (and a shallow footing) system, the stability values (SV) of 0 and 1 (indicating the stability and failure, respectively) are set as the targets. Each model predicted the SV for 901 stages. The results indicated that the BHA and MVO can increase the accuracy (i.e., the area under the receiving operating characteristic curve) of the ANN from 94.0% to 96.3 and 97.2% in analyzing the SV pattern. Moreover, the prediction accuracy rose from 93.1% to 94.4 and 95.0%. Also, a comparison between the ANN's error decreased by the BHA and MVO (7.92% vs. 18.08% in the training phase and 6.28% vs. 13.62% in the testing phase) showed that the MVO is a more efficient optimizer. Hence, the suggested MVO-ANN can be used as a reliable approach for the practical estimation of bearing capacity.

• Journal of Power Electronics
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• v.17 no.4
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• pp.972-982
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• 2017

The Park's vector of stator current is a popular technique for the detection of induction motor faults. While the detection of the faulty condition using the Park's vector technique is easy, the classification of different types of faults is intricate. This problem is overcome by the Multiple Park's Vector (MPV) approach proposed in this paper. In this technique, the characteristic fault frequency component (CFFC) of stator winding faults, rotor winding faults, unbalanced voltage and bearing faults are extracted from three phase stator currents. Due to constructional asymmetry, under the healthy condition these characteristic fault frequency components are unbalanced. In order to balanced them, a correction factor is added to the characteristic fault frequency components of three phase stator currents. Therefore, the Park's vector pattern under the healthy condition is circular in shape. This pattern is considered as a reference pattern under the healthy condition. According to the fault condition, the amplitude and phase of characteristic faults frequency components changes. Thus, the pattern of the Park's vector changes. By monitoring the variation in multiple Park's vector patterns, the type of fault and its severity level is identified. In the proposed technique, the diagnosis of faults is immune to the effects of unbalanced voltage and multiple faults. This technique is verified on a 7.5 hp three phase wound rotor induction motor (WRIM). The experimental analysis is verified by simulation results.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.10a
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• pp.134-138
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• 2001

Basic governing equations for the Active Magnetic Bearing system are derived. Characteristic difference between PD and PID controllers are studied. It is shown that I-control action is able to minimize the steady state error and increase the stiffness in low frequency range.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.10a
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• pp.701-702
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• 2011

• Journal of the Mineralogical Society of Korea
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• v.19 no.3 s.49
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• pp.197-207
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• 2006

In the coal-bearing formations of the Janggi Group, which are reported as typical clastic sediments, several beds of volcaniclastic rocks are actually found in the Yeongil area. The coal-bearing formations generally exhibit alternating lithologic characteristics of pyroclastic and epiclastic sedimentary facies. Tuff and tuffaceous sandstone rich in pumice fragments are characteristic in the coal-bearing fermations. Diagenetic minerals found in the pyroclastic rocks of the upper and lower coal-bearing formations are montmorillonite, clinoptilolite, opal-CT, and quartz. Several tuffaceous beds correspond to the low-grade ores of zeolites and bentonite, and moreover, these ores mostly occur as thin beds less than 1 m in thickness. Thus, the potential of altered tuffaceous rocks as the resources typical of zeolite and bentonite seems to be low. However, based on mineral composition and CEC determinations, it can be evaluated that these tuffaceous rocks mostly have the promising potential for utilization as the absorbent-functional mineral resources such as acid clays, if these low-grade ores plus adjacent tuffaceous rocks are collectively exploited.

• Journal of Korean Physical Therapy Science
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• v.9 no.1
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• pp.53-59
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• 2002

This study is research for effect of the involved lower limb weight bearing training on symmetrical weight supporting rate improvement by practicing involved lower limb weight bearing training of three weeks period to improve standing equilibrium problem with asymmetric weight supporting rate of hemiplegia. In result of the study, it has shown that P-value incase of involved supporting rate is lower than level of significance $\alpha$<.05 and mean improvement rate of experienced group is higher in comparison with controlled group and experienced group. In changing quantity of involved maximum supporting rate, P-value is .26 and higher than level of significance $\alpha$<.05, and so it did not show significant difference statistically. But in case of experienced group between pre and post-test, involved side supporting rate and involved side maximum supporting rate showed significant improvement in all. In comparison of relative characteristic training effect difference, it was shown that train-learning effect on case of 40-60 years old, hemorrhagic patient and standard body bun of patient is valuable, which showed significant improvement in case of paralytic side and disease period, it did not show significant difference on excercise learning effect in two above cases. In the above result, we can say that continuous weight bearing training on the involved lower limb for three weeks period help improve the involved side supporting rate of hemiplegia. Accordingly, the weight bearing training on the involved lower limb is training method that patient can easily train with simple guidance of therapists, without being special expensive equipment. Furthermore it can be helpful to establish home therapeutic plan for hemiplegia through education of a patron.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2004.05a
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• pp.370-375
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• 2004

Fatigue tests were carried out to find the fatigue characteristics in the super-long life range by using a cantilever type rotational bending fatigue test machine. Three kinds of specimen in bearing steels with the quenched and tempered in air (A and B, B: shot peened after heal treatment) and under vacuum conditions(C:non-shot peened)were tested in this study. S-N curves obtained from fatigue tests of C specimen tend to come dawn again in the super-long life range due to fish-eye type cracking, while most of A and B specimens fractured by surface defects such as scratches and slip lines. This duplex S-N behavior for the high strength steels have to be reviewed by the change of fracture modes.