• Journal of Korea Water Resources Association
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• v.42 no.9
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• pp.759-771
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• 2009

The electricity cost of pumping system accounts for a large part of the total operating cost for long distance water supply networks. This study presents a method based on dynamic programming for establishing an joint optimal operation of pumps and storages system on a hourly basis. Analysis is taken of the relative efficiencies of the available pumps, the structure of the electricity tariff, the consumer-demand pattern, and the storage characteristics and operational constraints of the pipe. The possible system objectives and constraints are described. An application of the method to the existing Yangju Water Supply System consisted of two pump station and 5 storage pools under the condition of expanding pumping facility in the part of the Capital Area Water Supply System is presented, showing that considerable electricity cost savings are remarkable. The approach was found to be implementable in real system operation and large-scale water supply system design in respect of minimizing life-cycle total cost.

• Journal of Conservation Science
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• v.27 no.4
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• pp.451-458
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• 2011

This study aims at identifying wall painting production technique of Songsanri No. 6 tomb based on optical examination and scientific analysis along with the investigation of written records of ancient wall paintings. The result displays that bricks with mortar were used for the construction of the wall, and masonry joint were made of lime, sand and gypsum. The surface of brick were plastered with black and thereafter with white lime. Finely sifted clay on the top of the white surface, were applied not with plasterer's trowel but with a brush for making ground surface. The clay are mineral particles smaller than $30{\mu}m$ of silt. The wall paintings of Sonsanri No. 6 is the only example of making ground layer with clay for painting of Sasindo (literally four heavenly animals painting) among remaining wall paintings of ancient tombs. The historical value of the painting should be attributed not only in terms that it displays a rare production techniques which were never discovered in any other paintings in Korea and Asia, but also it might had been uncompleted when the tomb were closed, even though it considers the fact that the wall painting were discovered in damaged condition in 1933.

• Composites Research
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• v.31 no.1
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• pp.17-22
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• 2018

Long Fiber Prepreg Sheet (LFPS) has the advantages of excellent production efficiency and formability for complex shapes compared to conventional continuous fiber reinforced composites. When fibrous composites are used with different materials, joining method is important because strength of the joining part determines the strength of the hybrid structure. In this study, the adhesive joint strengths of co-cured LFPS and aluminum were evaluated under various surface treatment conditions and environmental conditions (temperature and moisture conditions). Mechanical abrasion and plasma exposure were used for the surface treatment. The adhesive joints experienced various surface treatments were tested by using single lap joint specimens. Adhesive strengths under various conditions were compared and the most appropriate condition was determined.

• Journal of Korean society of Dental Hygiene
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• v.18 no.5
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• pp.665-674
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• 2018

Objective: The purpose of this study was to reduce the burden on dental hygienists in performing dental hygiene processes in the clinic. This study systematically analyzed dental hygiene problems and dental hygiene planning according to the oral condition of patients by applying an oral health care program based on the dental hygiene process. Methods: This study analyzed influential factors of 17 dental hygiene problems and 12 dental hygiene plans according to the oral health index and charts of 185 patients. This study was approved by the Institutional Review Board (IRB No. 1041449-201801-HR-003) of Silla University. The frequency of dental hygiene problems and dental hygiene planning was analyzed and correlations among the oral health index, dental hygiene problems, and dental hygiene planning were analyzed. Results: The higher the bleeding on probing score was, the more scaling was planned. The higher the calculus rate was, the more air-jet and jaw joint disorder prevention education was planned. The higher the O'Leary index was, the more dietary education and air-jet was planned. The higher the Simplified Oral Hygiene Index was, the more air-jet and jaw joint disorder prevention education was planned. The higher the Periodontal Screening and Recording index was, the more scaling and professional tooth cleaning was planned (p<0.05). Conclusions: The burden of oral preventive duties on dental hygienists will be minimized by systematically establishing problems and planning of dental hygiene according to patients' oral health index scores. Therefore, it is expected that dental hygienist can actively use the dental hygiene process in oral health care programs.

• Journal of Welding and Joining
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• v.17 no.1
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• pp.97-103
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• 1999

Ships, structures on the ocean, bridges, and other structures tend to be large by the development of industry. These ultra thick plate were welded with large heat input, which causes welding stresses, deformation and buckling, so it has to be considered the weld design, safety, reliability. The welded residual stresses were produced and redistributed due to the effect of large heat input. The mechanical phenomenon has not been surely identified yet. In spite of the lack of the study on the box column, there are various types of steel frame such as I type, H type, + type and $\bigcirc$ type, used in high story building. In this study, we performed computer simulation with two dimensional heat conduction and plane deformation thermal elasto-plastic finite element computer program as changing the plate thickness to 100mm, 150mm and groove angle to $60^{\circ}C$, $45^{\circ}C$, $30^{\circ}C$ of corner joint in box column. And then, to identify mechanical phenomenon such as the phenomenon of thermal distribution, welding residual stresses and deformation and to decide optimum groove angle and welding condition. The main conclusion can be summarized as follows: 1) Since the groove angle has became cooling down rapidly due to its smaller value, the temperature slope was steeped somewhat. 2) The tensile stress within the welding direction stresses was somewhat decreased at the weld metal and HAZ, increasing of the groove angle. 3) The local stress concentration of the groove angle $60^{\circ}C$ was appeared smaller than groove angle $30^{\circ}$.

• Journal of Korea Foundry Society
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• v.21 no.4
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• pp.239-245
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• 2001

Microstructure and mechanical properties of Sn-3.1 wt.%Ag-6.9 wt.%Bi system solders on Cu-substrate were studied. The Sn3.1 wt.%Ag-6.9 wt.%Bi alloy was designed by phase diagram and chemical properties and was prepared by melting in argon atmosphere. The mechanical properties of solder/Cu joints were examined by shear strength test, and also creep test. The microstructure of Sn-3.1 wt.%Ag-6.9 wt.%Bi alloy consists of Bi-rich phase and $Ag_3Sn$ precipitate in {\beta}-Sn$ matrix phase. The shear strength of the joint was decreased with aging treatment. Crack path under shear test was through the solder. Similar crack path change mode was observed at the creep test of solder/Cu joint. The creep behavior of Sn-3.1 wt.%Ag-6.9 wt.%Bi alloy represented the inverse primary creep behavior at all test condition. It is suggested that the inverse primary creep behavior is induced from Bi solute atoms in Sn-matrix. The creep resistance of Sn-3.1Ag-6.9Bi alloy is better than that of Sn-3.5 wt.%Ag alloy at all test conditions.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.2
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• pp.141-146
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• 2002

Purpose: Various treatment methods have been utilized for recurrent dislocation of the TMJ (temporomandibular joint). The purpose of this study is to define the effect of the eminectomy with discoplasty that had been performed in patients with TMJ luxation. Materials and Methods: Twenty patients (22 joints), whose diagnosis were TMJ dislocation were selected in 772 patients (871 joints) who had been underwent TMJ surgery between 1988 and 2000. The selected patients were divided into two groups. Group I (12 joints) was the habitual-luxation group which involves the recurrent TMJ dislocation patients. Group II (10 joints) was the open lock-history group which involves the patients who had more than two episodes of TMJ luxation and TMJ disorders. The history of TMJ luxation, maximum mouth opening and other TMJ signs and symptoms before and after surgery were reviewed. Results: In group I, one patient who had been underwent both TMJ operation had a intermittent locking, but it disappeared after post-operative 32 months. In group II, intermittent pain was present in one patient who had bruxism, but it was disappeared by splint therapy. No more TMJ dislocations and other pains were checked in other patients of group I and II. Conclusion: Eminectomy with discoplasty may be used to successfully treat the TMJ habitual luxation accompanied with abnormal condition of the disc-condyle complex.

• Journal of muscle and joint health
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• v.2 no.2
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• pp.131-146
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• 1995

Many arthritis patients experience weakness of muscles in extremities mainly due to disuse atrophy and weight gain because of the limited activities and exercises. This study examines the effects of the 6-week aquatic-exercise program on the body fat and the muscle of the rheumatoid arthritis patients. Seventeen patients in the experimental group and 18 in the control group were assigned depending on their preference and physical condition. These patients had more than 3 points of pain out of 10, deformities in knee, wrist and ankle joints. The amount of aquatic exercise increases from 35 minutes in the first week to 60 minutes in the 6th week. In the resting period they discussed their own experiences about exercise, personal and family affairs, and performed some recreation programs in order to increase the self-efficacy and promote the relationship with other patients by the group activities. Skinfold thickness and circumferences of both extremities were measured before and after experiment to compare the difference. For testing the body fat Saham Model was used. Prior to the experiment two group's body weight, skinfold thickness and skin circumferences were not significantly different which indicates the homogeneity of two groups. Body weight and most parts of skinfold thickness of the experimental group were significantly lower than the control group after 6-week aquatic exercise program. Circumference was not significantly lower than the control after the program. These findings indicate the in-crease of muscle sizes and the reduction of the body fat. Therefore a more active application of aquatic exercise into a variety of clients is strongly suggested.

• Journal of muscle and joint health
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• v.2 no.2
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• pp.185-196
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• 1995

The purposes of this study are to identify effectiveness of the hospital-based home care project, to manage patients' problems in comprehensive way, to decrease the patients' economical burden to the arthritis patients. The design is nonequivalent control group pretest-posttest design with matched samples in terms of age, sex and disease severity. Fifty two patients were assigned in each of the experimental and control groups in Seoul, Kyunggi, Kangwon and Kwangju. Before the experiment and after 3-month period of experiment of home care, level of pain, duration of morning stiffness, Richie Index, ADL, self-efficacy and depression were measured. Nine patients were excluded from the control group because of denial of participation. Contents of home care provided to the experimental group include distribution of prescribed drugs, assessment of patient's condition and side-reactions of drug, pain control, depression control, nutrition guide, exercise teaching, and family counselling. Patients assigned to the control group visited the outpatient clinic once a month as usual. Null hypotheses were selected because physicians concerned about the ineffective change of patients' conditions due to indirect communication with patients through nurses. Level of pain, Richie Index, ADL, self-efficacy, depression and duration of morning stiffness did not significantly different between two groups as expected. In the experimental group, level of pain, ADL, Richie Index and duration of morning stiffness changed to the positive direction from the pretest to the posttest. However, level of depression and self-efficacy did not show any changes. Ninety percent of patients in the experimental group satisfied with the home care provided to them. Since this is the intermediate report, more detailed and long-term report will be prepared.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.9 no.1
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• pp.39-52
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• 2003

The test for internal and external rotation of hip joint, was donet from September 2 to 9, 2002, with the participation of 50 male/female university students who are in a normal health condition. Results are : 1. When applying the external rotation of 45 degrees angle ; 1) In a sitting position, for male it results in an increase of 5 degrees on right and left sides each. 2) In a sitting position, for female there is no change on both right and left sides. 3) In a supine position, for both male and female it results in an increase of 5 to 10 degrees on right and left sides each. 4) In a prone position, for male it results in an increase of 5 degrees on the left side only. 5) In a prone position, for female it results in an increase of 5 to 10 degrees on right and left sides each. 2. When applying the internal rotation of 45 degrees angle ; 1) In a sitting position, for male it results in a decrease of 5 degrees on right and left sides each. 2) In a sitting position, for female there is no change on both right and left sides. 3) In a supine and prone position, there is no change for male. 4) In a supine position, for female it results in an increase of 5 to 10 degrees on right and left sides each. 5) In a prone position, for female it results in an increase of 5 degrees on right and left sides each.