• Membrane Journal
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• v.27 no.3
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• pp.248-254
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• 2017

In order to secure the reliability of pathogenic microorganisms such as Cryptosporidium and Giaridia, which are chlorophilic protozoans, membrane filtration systems have been widely used in water purification process. hese integrity tests are classified into direct and indirect methods. Based on the bubble point theory, the pressure-based test in the direct method is presented in the USEPA Guidance Manual with sensitivity to detect a minimum size of pathogenic microorganisms of $3{\mu}m$ or more. Indirect methods are widely used in that they are capable of continuous operation in on-line state, but there is a very low sensitivity of damage detection compared to the direct method, and there is a limit that can not specify the damage area, so it is necessary to improve this sensitivity. In this study, we compared the LRVDIT and UCL values according to the type of membrane defect, number of fiber breaks, and initial set pressure value through the Integrity Test by Pressure Decay Test (PDT).

• Journal of the Korea Organic Resources Recycling Association
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• v.5 no.1
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• pp.53-61
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• 1997

This study was conducted to analysis citizen's attitude and style to the foodwaste from l0th Sept. to 30th Sept. in 1996. The research was used questionare method and analysis was used prequency analysis and cross table method by SPSS (scientific statistics). The foodwaste of householdwaste account for 24.8%, and the magnitude by the kinds of garbage were waste from pre-cocking stage, fruitshell, foodwaste remained after eating, septic foodwaste during storage. The more the housewives'age are young, foodwaste volumne were much. Most remained foodwaste after eating were soup and pot stew. The main cause of foodwaste production was overvolumne cooking. 88.8% of answers think that a menu can be useful to reduce foodwaste. The survey showed that 87.3% of answers put into the meter-rate bag after removed wetness of garbage. 84.1% of answers thought that the recycling of foodwaste needed, but the practical housewife was only 21%. For the suitable treatment of foodwaste, Survey showed that the consistent policy of goverment and continuous publicity was needed essentially, and that the public notice of TV or radio was effective. All of answers would like to participate in recycling of foodwastes whether public-posting or personal-posting. To set up vessel of posting at household, the proper purchase price and space of institution are needed, also the solution of sanitory & aesthetic problem and the collection of composting-product must be achieved smoothly.

• Korean Journal of Community Nutrition
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• v.20 no.5
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• pp.351-361
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• 2015

Objectives: The purpose of this study was to investigate the relations between diabetic dietary compliance and dietary intake, physical activity and prevalence of metabolic syndrome (MS) in type 2 diabetic patients. Methods: Seventy five subjects diagnosed with type 2 diabetes visiting the D hospital in Dongducheon from May 2014 to Dec 2014 were included in this study. The subjects were divided into two groups according to their diabetic dietary compliance score (median 39); low diabetic dietary compliance (LDDC) group (n=44) and high diabetic dietary compliance (HDDC) group (n=31). Survey data collection was carried out by direct interview method. The nutrient intake, food intake and KDDS (Korean's dietary diversity score), DVS (dietary variety score) and GMVDF (grain, meat, vegetable, dairy and fruit) were analyzed using data from the 24-recall method. Metabolic parameters were obtained from the hospital records. Data was analyzed using Chi-square test and general linear model adjusted for sex. Results: The prevalence of MS was 59.7% in the participating diabetic patients. The prevalence of MS of the HDDC (39.3%) was significantly lower than that of the LDDC (72.7%). The distribution of physical activity showed a significant difference between the groups (p=0.006). The intakes of seeds and nuts of the HDDC were significantly lower than those of the LDDC. Fat and vegetable fat intakes and % fat of energy in the HDDC were significantly lower than those in the LDDC. But, carbohydrate (CHO) and potassium intake and %CHO of energy in the HDDC were significantly higher than those in the LDDC. KDDS and GMVDF showed significant differences between groups (p=0.033; p=0.012). Conclusions: Continuous intervention by specialized nutritionists for long-term self-regulation is needed for diabetic patients, and the high compliance to diabetic diet and increasing physical activity may be effective in the prevention of metabolic syndrome.

• Applied Chemistry for Engineering
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• v.10 no.5
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• pp.796-803
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• 1999

Solution copolymerization of styrene(St.) with methyl methacrylate(MMA), ethyl methacrylate(EMA) and n-butyl methacrylate(BMA) was carried out with benzoylperoxide(BPO) as an initiator in toluene at $80^{\circ}C$ in a continuous stirred tank reactor. Reaction volume and residence time were 0.6 liters and 3hours, respectively. The monomer reactivity ratios, $r_1(St.)$ and $r_2(RMA)$ determined by both the Kelen-Tudos method and the Fineman-Ross method were $r_1(St.)=0.60(0.61),\;r_2(MMA)=0.59(0.60);\;r_1(St.)=0.65(0.62),\;r_2(EMA)=0.55(0.52);\;r_1(St.)=0.75(0.67),\;r_2(BMA)=0.63(0.56)$. The cross-termination factor $\Phi$ of the copolymer over the entire St. compositions ranged from 0.26 to 0.96. The $\Phi$ factors of St.-RMA copolymer were increased with increasing St. content. The simulated conversions and copolymerization rates were compared with the experimental results. The average time to reach dynamic steady-state was three times and half of the residence time.

• Restorative Dentistry and Endodontics
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• v.31 no.2
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• pp.119-124
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• 2006

The purpose of this study was to evaluate the effect of newly developed endodontic root canal cleanser (MTAD) on the apical leakage of obturated root canal using an electrochemical method. Canals of 60 extracted single-rooted human teeth were prepared by using a crown-down technique with rotary nickel-titanium files. In Group 1 (positive control group) and 2 (negative centre) group), 5.25% NaOCl was used as a canal irrigant and no canal wall treatment was done. In group 3 only 5.25% NaOCl were used as canal irrigant, canal wall treatment and final rinse. In group 4, specimens were irrigated with 5.25% NaOCl, treated with 5 ml of 17% EDTA for 5 minutes and final rinsed with 5.25% NaOCl Specimens of group 5 were irrigated with 1 3% NaOCl and treated with 5 ml of MTAD for 5 minutes. All root canals are dried with paper points and obtuated with gutta-percha and AH plus as a sealer using a continuous wave of condensation technique except in the group 1. The electrical resistance between the standard and experimental electrodes in canals was measured over a period of 10 days. Rising of apical leakage with time was observed for all the groups. Group 4 and 5 showed lower apical leakage than group 3 but differences between the group 3, 4 and 5 were no statistical significance at any measurement time.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.456-456
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• 2009

Boron doping on an n-type Si wafer is requisite process for IBC (Interdigitated Back Contact) solar cells. Fiber laser annealing is one of boron doping methods. For the boron doping, uniformly coated or deposited film is highly required. Plasma enhanced chemical vapor deposition (PECVD) method provides a uniform dopant film or layer which can facilitate doping. Because amorphous silicon layer absorption range for the wavelength of fiber laser does not match well for the direct annealing. In this study, to enhance thermal affection on the existing p-a-Si:H layer, a ${\mu}c$-Si:H intrinsic layer was deposited on the p-a-Si:H layer additionally by PECVD. To improve heat transfer rate to the amorphous silicon layer, and as heating both sides and protecting boron eliminating from the amorphous silicon layer. For p-a-Si:H layer with the ratio of $SiH_4$ : $B_2H_6$ : $H_2$ = 30 : 30 : 120, at $200^{\circ}C$, 50 W, 0.2 Torr for 30 minutes, and for ${\mu}c$-Si:H intrinsic layer, $SiH_4$ : $H_2$ = 10 : 300, at $200^{\circ}C$, 30 W, 0.5 Torr for 60 minutes, 2 cm $\times$ 2 cm size wafers were used. In consequence of comparing the results of lifetime measurement and sheet resistance relation, the laser condition set of 20 ~ 27 % of power, 150 ~ 160 kHz, 20 ~ 50 mm/s of marking speed, and $10\;{\sim}\;50 {\mu}m$ spacing with continuous wave mode of scanner lens showed the correlation between lifetime and sheet resistance as $100\;{\Omega}/sq$ and $11.8\;{\mu}s$ vs. $17\;{\Omega}/sq$ and $8.2\;{\mu}s$. Comparing to the singly deposited p-a-Si:H layer case, the additional ${\mu}c$-Si:H layer for doping resulted in no trade-offs, but showed slight improvement of both lifetime and sheet resistance, however sheet resistance might be confined by the additional intrinsic layer. This might come from the ineffective crystallization of amorphous silicon layer. For the additional layer case, lifetime and sheet resistance were measured as $84.8\;{\Omega}/sq$ and $11.09\;{\mu}s$ vs. $79.8\;{\Omega}/sq$ and $11.93\;{\mu}s$. The co-existence of $n^+$layeronthesamesurfaceandeliminating the laser damage should be taken into account for an IBC solar cell structure. Heavily doped uniform boron layer by fiber laser brings not only basic and essential conditions for the beginning step of IBC solar cell fabrication processes, but also the controllable doping concentration and depth that can be established according to the deposition conditions of layers.

• Korean Journal of Environment and Ecology
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• v.22 no.4
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• pp.453-460
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• 2008

This study conducted an analysis of plant species composition and vegetation at sea cliffs of the uninhabited islets off Ganghwa-gun by applying discontinuous classification method & continuous ordination method of species composition table by correlation. The analysis results are as follows: First, the plant showing the highest appearance frequency was Parthenocissus tricuspidata Planch.(58.3%), followed by Carpinus coreana Nak., Viburnum carlesii Hemsl. and Kalopanax septemlobus Koidz.(37.5%,respectively). As for a plant community, it was found that it consisted of Quercus mongolica community, Tilia mandshurica community, Carpinus coreana community, Sorbus alnifolia community and Pinus thunbergii community; as for the community distribution classified by individual islet, it was revealed that Quercus mongolica community appeared at Sosongdo and Bunjido; Tilia mandshurica community at Sosongdo and Daesongdo; Carpinus coreana community appeared at Woodo, Suribong and Bido; Sorbus alnifolia community at Susido, Sosongdo and Daesongdo, and Pinus thunbergii community at Seokdo and Woodo, respectively. The plant similarity classified by uninhabited islet was found to be the highest at Sosongdo and Daesongdo. This research judged the reason why the typical grassland community of coastal cliffs did not join these islets to be environmental conditions of rock landform where there exists almost no surface soil at most sea cliffs; thus, more detailed study on this was required.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.6
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• pp.225-229
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• 2011

Most of the silicon cutting methods using the multi-wire with the slurry injection have been used for wafers of the crystalline solar cell. But the productivity of slurry injection cutting type falls due to low cutting speeds. Also, the direct contact with the metal wire and silicon block increases the concentration of metallic impurities in the wafer's surface. In addition, the abrasive silicon carbide (SiC) generates pollutants. And production costs are rising because it does not re-use the worn wire. On the other hand, the productivity of the cutting method using the diamond coated wire is about 2 times faster than the slurry injection cutting type. Also, the continuous cutting using the used wire of low wear is possible. And this is a big advantage for reduced production costs. Therefore, the cutting method of the diamond coated wire is more efficient than the slurry injection cutting technique. In this study, each cutting type is analyzed using the surface characteristics of the solar wafer and will describe the effects of the manufacturing process of the solar cell. Finally, we will suggest improvement methods of the solar cell process for using the diamond cutting type wafer.

• Journal of Korean Academy of Nursing
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• v.3 no.3
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• pp.119-132
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• 1973

This study observed on habitual methods of toilet training for infants and toddlers in Korea thru 300 mothers at four medical institutions Ewha Woman′s University Hospital, Ewha Maternal and Child Health Center, Severance Hospital and Seoul National University Hospital) with a design to analyze beginning time, duration of period, methods employed, motives, equipments used, special terminology used for the subject training. The main purpose of this study was to generalize the proper methods of toilet training, and also to contribute a better psychological education for the mother and child. The results obtained from this study were as follows; 1. Majority of (67.3%) observed were in the age category between 30 and 40 years, and dominant numbers (64.7%) were housewives with high level of education and from middle class family background. 2. In the most cases (85%), toilet training was carried out by mothers(including wives who had a job) while more than half of mothers (53.7%) maintained their important motive for the training was "due to having high regard for cleanliness" 3. As for the time of beginning toilet training: finding indicated that starting period was decided (70%) at inconsiderate desertion of each mother. whereas, only minority group (30%) represents the cases where mother started the training when they consider tile child was physically and psychologically randy. Also greater number (77.7%) started bladder training prior to that of bowel. 4. It is noticeable that in course of training a large number of mothers (48.3%) applied strict training method when the child proper talenting, and the more rigid and strict in tile training. the more malformation of personality of the infant and toddler were seen after the training period (P<0.01). 5. Over the half of the total cases denoted (bowel 54.3%, bladder 67.7%) starting period before one year and in most cases (bowel 79.3%, bladder 729)the training was accomplished within 12 month, and therefore it was noted that earlier start(before 1 year) shortened the training period (with 12 month) . There was no significant difference between male and female infants in both starting period and duration of period in bladder training, however, in bowel training there was a tendency that female started earlier(7-12 months needed, 51.4%) than tile male (13-18 months needed, largest number 41.4%), and also in cases of female the period for needed for training were shorter than the cases of male. 6. Many a number (bowel 50.3%, bladder 97.7%) employed the method of continuous talenting at regular interval in accordance with that of child′s habit formed before training. Equipment used were various kinds, however, pieces of paper for male (45.5%) and piss pot or bedpost (42.3%) for female were common, on the other hand, "Eung-ga" for defecation (52.3%) and "Shii" for the urination (95.3%) were most standard expression that used during the training period.

• Journal of the Korean earth science society
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• v.36 no.3
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• pp.222-235
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• 2015

Samples were collected from both places including the coastal area within the height of 5 m above the mean sea level (msl) (DH) and the top of the coastal terrace of 10-15 m msl (KS) high in Gwangseungri, Gochanggun, Korea. To find the origin of the deposit in the coastal area, granulometric analysis and geochemical analysis were performed. The result showed that the DH samples were originated from the reddish soils overlaying weathered bedrock which presented gradual change of chemical composition from the bottom toward the top. Clay minerals were found from the DH samples. These results concluded that the DH samples were found as in-situ weathered materials. The KS samples were originated from the soil layer covering gravel layer at the foot slope of the hill along the coast. The KS samples contained different chemical compositions from the DH. It is inferred that some of this layer was disturbed or experienced the influx of foreign material. The particle size of the KS samples was different from those found on the beach. The particle size of lower parts of KS site was finer than that on the beach, but the particle size of middle part of the site was coarser than that on the beach. The sorting of the KS site was poorer than that on the beach. Thus, it is inferred that some parts of the layer were formed by short-lived high energy event rather than sustained and continuous action of tidal currents and/or waves. Analysis using an optically stimulated luminescence (OSL) method showed that the burial age of samples from KS site were found 0.65-0.71 ka. Though the characteristics of the sediment layer and forming event in this area should be further studied, it can be inferred that this sedimentary layer formed by coastal flooding with storm.