• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.24 no.2
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• pp.55-64
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• 1988

Stow nets have widely been used in the western sea of Korea from the olden age. The original structure of a stow net is a large square-sectional bag net made of 4 netting panels, and the front fringes of top and bottom panels are connected to the top and bottom beams respectively. Wire ropes, which is originated from the holding anchor are gradually forked and biforked, and finally 4 pieces of wire rope (biforked pendants) are jointed to each beam. Much convenience caused by long and heavy beams were problemed, then some studies have been carried out to improve the net since 1930's. The most effective improvement were achieved in 1980 by Mr. Han and his colleagues. The key point of improvement was that the beams were removed and the belt shaped shearing device made by canvas was attached to the side panels, the head rope and ground rope to the front fringe of top and bottom panel, and biforked pendants are joined to the shearing device. Even though this is the epoch-making improvement of a stow net, the further study should be required to find out more effective method. The authors carried out a model experiment on the stow net to determine the vertical and horizontal opening of a net mouth, and also examine the front, top and side-view configuration of the net. The model net was constructed depending on the Similarity Law of Fishing Gear in 1/10 and 1/20 scale and set against to the current at shallow and speedy flowing channel. The vertical and horizontal openings were determined by using scaled bamboo poles, and the configuration was observed by using specially prepared observation platform and underwater observation glass, and also photographed by using specially prepared underwater photographic equipment. The results obtained can be summarized as follows: 1. The opening height and width of the shearing device varied in accordance with the relative length of the biforked pendants. Considering the height and width of shearing device in 6 cases of the arrangement system of biforked pendants, the best result was obtained in the case that the 2nd, 3rd and 4th pendents from the bottom-most was 5%, 9% and 4% longer than that. 2. On the top-view configuration the excessive deformation of head rope and ground rope were observed. In the actual net, 54m long head rope and ground rope were attached to the front fringe of top and bottom panels so that the head rope may be lifted to make the net mouth open highly. But actually the head rope and the ground rope are streamed backward without any lift, and also the netting followed the ropes were deformed until the 2/5 in the whole length of the net. This deformation may be guessed to disturb the entrance of fish school into the net and also caused the net to get caught by obstacles in the sea bed and to be broken largely. 3. Hydrodynamic resistance R of the actual net may be deduced as R(kg)=29.2$\times$103 v1.65. It is also expressed as R(kg)=5.9$\times$d/l$\times$ab v1.65. depending on the formula deduced by Koyama to estimate the resistance of trawl nets, where d/l denote the ratio between diameter of netting twine and length of mesh leg in every part of side panel, a and b, the stretched circumference of the mouth and the stretched length of the net, respectively.

• Explosives and Blasting
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• v.21 no.3
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• pp.23-35
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• 2003

An analytical diffusion model for flood routing with backwater effects and lateral flows is developed. The basic diffusion equation is linearized about an average depth of (H + h), and is solved using the boundary conditons which take into account the effects of backwater and lateral flows. Scouring phenomenon around pier which affects on the support function of pier and the stabilization if river bed is a complex problem depending on flow properties and river bed state as well as pier geometry. therefore, there is no uniting theory at present which would enable the designer to estimate, with confidence, the depth of scour at bridge piers. The various methods used in erosion control are collectively called upstream engineering, HEC-RAS Model, underwater blasting. They consist of reforestation, check-dam construction, planting of burned-over areas, contour plowing and regulation of crop and grazing practices. Also included are measures for proper treatment of high embankments and cuts and stabilization of streambanks by planting or by revetment construction. One phase of reforestation that may be applied near a reservoir is planting of vegetation screens. Such screens, planted on the flats adjacent to the normal stream channel at the head of a reservoir, reduce the velocity of silt-laden storm inflows that inundate these areas. This stilling action causes extensive deposition to occur before the silt reaches the main cavity of the reservoir.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.10
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• pp.684-693
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• 2012

The stormwater runoff from the increasing paved roads and vehicles resulted in the increase in the pollutants load to adjacent water bodies. The granular media filtration facilities are the most widely adopted to minimize the non-point source pollution from motorways. It is essential to consider the severe variation of hydraulic condition, suspended solid (SS) characteristics, and the medium characteristics for stormwater management filter. In this study, different types of media, including sand, were tested and the performance of downflow sand filters was investigated under various linear velocity and influent solid particle size. Results showed that the best medium is the coarse sand with large grain size, which showed the specific SS removal before clogging of more than $8.498kg/m^2$, the SS removal of higher than 95%, and minimum head loss. Linear velocity did not affect the total solid removal, while the performance was improved when fine solid was introduced. It is suggested that the life of a downflow sand filter bed can be extended by deep bed filtration when influent particles are fine. However, the captured particles can be washed out after a long period of operation.

• Journal of Korea Water Resources Association
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• v.53 no.11
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• pp.951-960
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• 2020

This study investigates the adjustment processes of the rivers after weir removal through laboratory experiments. Delta upstream eroded rapidly by flow at the initial stage of the experiments and the knickpoint migrates upward. Moreover, the knickpoint moves fast upward on the condition of alternate bars. The head cutting in the bed is developed fast at the initial stage. However, the erosion speed in the bed decreases with time. The well developed alternate bars migrates with keeping their shape downstream, and the bars affect the channel downstream to adjust new environments after weir removal. Maximum scouring depth downstream and the migration speed decrease over time after removing the weir. The scouring depth in the channel without alternate bars migrates with speed. However, the depth in the channel with alternate bars migrates slow downstream. The channel with alternate bars, in turn, is adjusted well to the new equilibrium states. The maximum scouring depth migrates downstream with time, and the scouring depth and its migration speed decreases with time. The dimensionless maximum scouring depth decreases with the migration speed of dimensionless maximum scouring depth because the deeply scoured places capture the sediments from upstream and the migration speed is slow as the places are filled with them. The dimensionless maximum scouring depth is shallow as the dimensionless backfilling speed is high. The dimensionless maximum scouring depth decreases rapidly less than 5 of dimensionless backfilling speed. However, the depth decreases slow more than 5 of it.

• Korean Journal of Head & Neck Oncology
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• v.16 no.2
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• pp.167-171
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• 2000

Objectives: To compare the outcomes of treatment with a focus on the effectiveness of the two primary techniques of radiation used for treating parotid gland malignancies. Materials and Methods: A retrospective analysis of 70 patients with parotid gland cancer treated between 1981-1997. Radiation was delivered through an ipsilateral field of high energy electron and photon in 37 patients(52.9%). Two wedge paired photon was used to treat in 33 patients(47.1%). The median dose was 60 Gy, typically delivered at 1.8-2.0Gy per fraction. The median follow-up times for surviving patients was 60 months. Results: The overall and disease free 5 year survival rates were 71.6% and 69.5%, respectively. Wedge paired photon and photon-electron treatment disease tree 5 year survival rates were 61.1% and 80.5%, respectively. Overall local failure rate was 18.6%. Local failure rate of wedge paired photon technique was higher than that of mixed beam technique. Late complication rate was 37.1%, but most of them were mild grade. Conclusion: Techniques of radiation were associated with local control. The technique of using an ipsilateral field encompassing the parotid bed and treated with high energy electrons often mixed photons was effective with minimal severe late toxicity. To irradiate deep sited tumors, we consider 3-D conformal treatment plan for well encompassing the target volume.

• Clinical and Experimental Pediatrics
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• v.46 no.12
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• pp.1274-1278
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• 2003

Syncope in children and adolescents have a common occurrence according for up to 15% before adulthood. Micturition syncope, a kind of situational syncope, can be considered a form of reflex syncope. It can typically occur in healthy young men after rising from bed in the early morning who experience sudden loss of consciousness during or immediately after urination. The mechanism of micturition syncope is not completely understood, but it has been suggested that vasovagal reflex mediated bradycardia and peripheral vasodilation and decreased venous return due to Valsalva effect and standing position lead to the decrease in cerebral blood flow resulting in syncope. The causes of syncope are variable. So complete history taking, physical examination, electrocardiography, exercise stress test, echocardiography, head-up tilt table test, electroencephalography(EEG), brain magnetic resonance image and urodynamic study should be required for the diagnosis of micturition syncope. There were several reports about micturition syncope. However, literature of micturition syncope at the pediatric age has rarely been reported in Korea so far. Therefore, we report a case of a 9-year-old boy with micturition syncope with typical EEG findings of high amplitude delta wave and flattening during syncope.

• Journal of Fashion Business
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• v.3 no.2
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• pp.85-90
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• 1999

A shroud is clothes for giving a dead person a bath and being finely dressed:though our routine clothes have been western, putting on a shroud has been kept comparatively well as a tradition of a conventional ceremony garments. This study is about the current using of dressing a shroud, and for presenting foundations of a way about dressing a shroud in order to make the most of this by everyone, therefore this research will be worthwhile to preserve the traditional custom of giving a dead person a bath and being finely dressed. 1. We must confirm the death of a person before we do Su-Si for controlling rightly a corse. Su-Si is ways of changing a clean clothes after bathing the dead person, tieing up hands, feet and ankles with a string, filling up a mouth, a nose and ears with a wad of cotton, laying down the dead person with his head toward east, and setting up a screen after covering the dead person with a bed sheet. 2. Here are processes of putting on a shroud. After the day of death, first of all, you must untie the string to control rightly a corpse, take off the clothes, and give a dead man a bath. You trim the dead person's fingernails and toenails, put them in O-nang, then put his hands and feet in five pouches, finally put feet in korean socks and wrap with Ak-su. You put a underwear in a overwear in order to put on the clothes easily, and then put on an upper garments after putting on trousers. And put on Sb-sin After you wash the dead person's face and his hair, you put gems and raw rice in his mouth, wrap head with cotton fabrics, and put hairs into five pouches, then put on a headgear which is filled with five pouches. 3. You tie up with hem cloth the dead person dressed a shroud after wrapping with Dae-ryum-km and So-ryumkm. 4. After you encoffin the dead person, you weave coffin strings with cotton fabrics in order to lift up the coffin easily, and lay down a red fabrics having white letters about the dead person's name or social position onto the coffin, then cover the coffin with a coffin cover : finally you leave the coffin at the former place and set up screen.

• Clinical and Experimental Pediatrics
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• v.53 no.11
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• pp.942-950
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• 2010

Purpose: The purpose of this study was to determine the mechanisms and exact causes of injuries to children by analyzing the medical records of children who visited emergency medical centers. Methods: We reviewed the medical records of 7,114 pediatric patients (aged below 15 years) who visited the emergency care center (ECC) of a Yeungnam university hospital in Daegu between January 2007 and December 2009. Results: Among the pediatric patients who visited the ECC, 1,526 (27.2%) were admitted for injuries (boys, 979 [64.2%] and girls, 547 [35.8%]); the boy-to-girl ratio in this study population was 1.8:1. The proportion of boys was higher than that of girls over all age ranges, except for children aged less than 1 year. The highest incidence of injury due to slipping (20.5%) was noted in the 1-year-old group, and nearly half the total number of cases (49.3%) involved children who were under 4 years of age. Of the sites of injury, 999 involved the head and face (73.7%) and 134 involved the hand and wrist (9.9%). Seventy-one injuries (5.7%) occurred on the bed, 70 (5.6%) at the door, and 67 (5.3%) on the stairs. Of the approximately 250 types of injuries classified by cause, 17 accounted for 50.4% of all the injuries. Conclusion: The cause of injury could be attributed to approximately 20 causes in more than half the cases of pediatric injuries. A classification of the types of injuries and the development of appropriate preventive strategies can help avoid such injuries.

• Journal of Korean Public Health Nursing
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• v.15 no.2
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• pp.324-333
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• 2001

The purpose of this cross-sectional study was to explore fear of falling in relation to activity restriction of in the community dwelling elderly. Two hundred ninety-nine community dwelling elderly residing in Seoul and Kyonggi-do were interviewed using a structured questionnaire. The results were as follows : 1. Subjects were predominantly women$(70.6\%)$, an average 72.5 years old; the incidence of falls in last one year was $45.5\%$. 2. The highest level of fear found for activity in those who say they do engage and those who do not engage in the activity was 'going out when it is slippery '(m=2.53, 2.81) and 'reach for something over your head'(m=1.66, 2.60). Fear of falling scores were significant lower for those who say they do engage in eight kinds of activities (excluded activities of given were 'go to the store', 'take a tub bath', 'get out of bed') than for those who do not engage in the activities. 3. Among those who did not perform the activity, the three activities, when it is slippy(n=80), reaching overhead(n=70), and walk outside(n=59),were most often avoided because fear alone as well as for reasons in addition to fear. 4. The significant variables associated with fear of falling were female(p=0.0000), 1 educational status(p=0.000l), poor economic condition(p=0.0007), and experience of falls in last one year(p=0.0007). Fear of falling is common in the community dwelling elderly in Korea and is associated with several demographical variables. Therefore, to prevent falls and to reduce fear of falling, further study for development of education program for the elderly is needed.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.2
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• pp.254-269
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• 2004

Polysilicato-iron coagulant (PSI) is receiving attention in Japan as a substitute for aluminum-based coagulants. In the first part of this article, coagulation, sedimentation and filtration experiments were carried out using kaolin clay particles as the turbidizing material and four types of PSI with various molar ratios of polysilicic acid to ferric chloride (Si/Fe ratio). Results demonstrate that use of a PSI with a high Si/Fe ratio can cause a more dramatic decrease in treated water turbidity but a higher suction time ratio (STR) than when PACl is used. However, optimization by increasing the rapid agitation strength GR is found to greatly improve the STR. In addition, the series of filtration experiments verified that optimization of GR is greatly effective in controlling rapid increases in filter head loss, and also formation of a thin aging layer in the upper part of the filter bed by slow-start filtration is effective in improving filtered water turbidity over the entire filtration process. The second part of this article describes two innovative filtration techniques to increase the particle separation efficiency; (1) coagulant-coated filter medium by enhancing the electrical potential of the surface of the filter medium, and (2) coagulant dosing in influent by controlling the electrical potential of particles entering the filter layer. From the results of the various filtration experiments using a pilot plant, these two techniques were found to be very effective to reduce the effluent water turbidity from the start to the end of a filter run. Moreover, in the filtration experiments using these two methods simultaneously, higher removal efficiency of approximately 3-log (99.7%) was realized, resulting that the finished water turbidity was accordingly reduced to 0.004mg/L.