• Journal of the Korea Concrete Institute
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• v.11 no.4
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• pp.21-29
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• 1999

In this study, an experiment was performed to analyze the influence of water-cement ratio on the fundamental characteristics of antiwashout underwater concrete using blended sand (sea sand:river sand = 1:1). The water-cement ratio (45%, 50%, 55%, 60%), andtiwashout underwater agent contents (0.82%, 1.00%, 1.14% of water contents per unit volume of concrete), and superplasticizer contents (1.5%, 2.0%, 2.5% of cement contents per unit volume of concrete) were chosen as the experimental parameters. The experimental results show that the underwater segregation resistance, unit weight of hardening concrete and compressive strength were increased as the water-cement ratio decreased and as the antiwashout underwater agent contents increased. On the other hand, the flowability(slump flow) was increased to the 55% of the increase of water-cement ratio, however, it was decreased at the ratio of 60%. From this study, the antiwashout underwater concrete can potentially be used as a materials underwater work of ocean if the water-cement ratio and chemical admixture contents for the suitable balance between cost and performance are properly selected.

• Proceedings of the Acoustical Society of Korea Conference
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• 1991.06a
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• pp.58-63
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• 1991

This paper describes development of small scale voice dialing system using TMS320C30. Recognition vocabuliary is used 50 department name within university. In vocabulary below the middle scale, word unit recognition is more practice than phoneme unit or syllable unit recognition. In this paper, we performend recognition and model generation using DMS(Dynamic Multi-Section) and implemeted voice dialing system using TMS320C30. As a result of recognition, we achieved a 98% recognition rate in condition of section 22 and weight 0.6 and recognition time took 4 seconds.

• Food Engineering Progress
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• v.21 no.4
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• pp.312-317
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• 2017

Weight loss that influences quality and farmer incomes is affected by the storage environment of agricultural products. The interior of storage should be maintained at high humidity to prevent the weight loss of products which contain a lot of moisture. The research had constantly proceeded with change in the heat exchanger surface areas, humidity systems, and weight loss forecast to maintain high humidity within storage. Relative humidity that exerts an effect weight loss of crop is influenced by storage temperature, leak state, and volume of product. When weight loss is predicted, different conditions of these factors are derived. In case of CA storage, ways of forecasting the weight loss become easier compared to cold storage due to sealed storage with external environment during storage period. In this study, apples were stored in purge-type CA storage and weight loss has been predicted by using operating characteristics and environmental conditions. As a result, humidity variation in the storage fluctuates with the operation of the unit-cooler. Furthermore, unit-cooler operation factor is influenced by outside temperature and respiration heat. Prediction value of weight loss according to temperature and humidity has been most accurately predicted. Prediction value through defrosting water measured shows unit-cooler work quality. K-value needs verification to calculate the VPD method.

• Journal of the Korean Society of Mechanical Technology
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• v.20 no.6
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• pp.936-940
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• 2018

Wasted meat & bone has generated as byproducts in the slaughtering process of livestock and also faced with demands for its recycling and environmental protection. Many studies have been conducted to recycle byproducts and carried out mainly on the crushing of bones and the vacuum packing technology of products. In this study, the crushing unit, transporting unit, separated unit and packing unit have designed for development of the crushing and packing systems. Also, to confirm the performance of this system, the experimental verification were carried out the working noise and packing weight.

• Genomics & Informatics
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• v.21 no.4
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• pp.47.1-47.12
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• 2023

Silver barb (Barbonymus gonionotus) is among the most economically important freshwater fish species in Thailand. It ranks fourth in economic value and third in production weight for fisheries and culture in Thailand. An XX/XY sex-determination system based on gynogenesis was previously reported for this fish. In this study, the molecular basis underlying the sex-determination system was further investigated. Genome-wide single-nucleotide polymorphism data were generated for 32 captive-bred silver barb individuals, previously scored by phenotypic sex, to identify sex-linked regions associated with sex determination. Sixty-three male-linked loci, indicating putative XY chromosomes, were identified. Male-specific loci were not observed, which indicates that the putative Y chromosome is young and the sex determination region is cryptic. A homology search revealed that most male-linked loci were homologous to the Mariner/Tc1 and Gypsy transposable elements and are probably the remnants of an initial accumulation of repeats on the Y chromosome from the early stages of sex chromosome differentiation. This research provides convincing insights into the mechanism of sex determination and reveals the potential sex determination regions in silver barb. The study provides the basic data necessary for increasing the commercial value of silver barbs through genetic improvements.

• Korean Journal of Agricultural Science
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• v.24 no.2
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• pp.218-225
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• 1997

This study was performed to evaluate the physical and mechanical properties of surlightweight polymer concrete using synthetic lightweight aggregate. The following conclusions were drawn; 1. Unit weight was in the range of $810~970kgf/m^3$, the unit weights of those concrete were decreased 58~65% than that of the normal cement concrete. 2. The highest strength was achieved by $P_1$, it was increased 112% by compressive strength, 378% by bending strength and 290% by tensile strength than that of the normal cement concrete, respectively. 3. Ultrasonic pulse velocity was in the range of 2,206~2,595m/s, which was low showed compared to that of the normal cement concrete. 4. Durability of surlightweight polymer concrete was superior to that of the normal cement concrete. 5. Compressive, tensile and bending strength were largely showed with the increase of unit weight. But, ultrasonic pulse velocity was low showed with the increase of unit weight.

• Journal of the Korean Society for Railway
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• v.10 no.5
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• pp.596-599
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• 2007

A comparative Life Cycle Assessment (LCA) among three types of Electric Motor Unit (EMU) Interior Panel (IP) was conducted. A functional unit for comparative LCA is a weight of IP for 1 EMU. It is assumed that Manufacturing stage and its upstream processes, Use stage and End of Life (EoL) stage are included in the boundary of product system. For Use stage, the weight of IP causes electricity consumption. It is assumed that aluminum IP is recycled and the other IPs are incinerated at the EoL stage. As a comparison results, aluminum IP has much larger environmental impact (5.162pt) than others (FRP IP; 4.069pt, Phenol IP; 4.053pt) even though recycling consideration is included. The manufacturing stage of aluminum IP has relative big environmental impact (1.824pt) and this point make the most important difference from other IPs (FRP IP; 0.1617pt, Phenol IP; 0.4534pt)). Despite of large weight difference between FRP IP (888.96kg) and phenol IP (316kg), the final environmental impact result has only little difference (0.016pt, 0.39%). With this result, the EMU designer can choose IP with a consideration of the environmental performance of IP.

• Journal of Korean Clinical Nursing Research
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• v.17 no.2
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• pp.239-250
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• 2011

Purpose: This study was aimed to evaluate the effects of Labor Support Behaviors (LSB) one-to-one application and partner's delivery participation on the delivery satisfaction and delivery results among mothers who delivered premature birth and low birth weight infant. Methods: The data were collected from 30 mothers in the experimental group and 27 in the control group from April 23, 2009 to April 22, 2010. The collected data were analyzed using percentage, mean, standard deviation, $x^2-test$ (Fisher's exact test) and t-test with SPSS. Results: The satisfaction levels of the experimental group and the control group women were $3.73{\pm}0.43$ and $3.72{\pm}0.34$ as mean values, respectively, showing not statistically different (t=0.07, p=.945). None showed less than 7 point of Apgar score at 1 minute in the experimental group while 5 out of 27 did (18.5%) in the control group, which was statistically meaningful. Also, the emergent cesarian section cases were 3 out of 33 (9.1%) in the experimental group and 5 out of 32 (15.6%) in the control group, demonstrating lower emergency cesarian section rate in the experimental group than the control group, but showing not statistically different ($x^2=0.643$, p=.475). Conclusion: The results of this study show that LSB one-to-one application and partner's participation has affirmative effects on 1 minute Apgar scores of newborns.

• Child Health Nursing Research
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• v.27 no.3
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• pp.297-307
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• 2021

Purpose: This descriptive study compared the perceived parental stress levels between parents with very low birth weight infants (VLBWIs) and nurses in the neonatal intensive care unit (NICU). Methods: In total, 83 parents of VLBWIs and 78 NICU nurses were enrolled. Data were collected with the Parental Stress Scale (PSS) and analyzed using the t-test and analysis of variance in SAS version 9.4. Results: The average PSS score was 3.31 among parents and 3.45 among nurses. The stress score was significantly higher among nurses with children (t=2.46, p=.016) and senior nurses (t=2.12, p=.037). There was a significant difference in the stress score according to parents' education (t=3.29, p=.002) and occupation (F=3.14, p=.049) in the sights and sounds subscale. Mothers had significantly higher stress scores than fathers in the parental role alterations subscale (t=2.32, p=.023). Parental stress scores were higher than those perceived by nurses in the infant's appearance and behaviors subscale for breathing patterns (t=2.95, p=.004), followed by jerky/ restless behavior (t=2.70, p=.008). Conclusion: Nurses should provide explanations to parents of VLBWIs in order to reduce parental stress about the appearances and behavior of VLBWIs. This is more important than aspect of the NICU environment and education about parental roles.

• Journal of the Korean Society of Industry Convergence
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• v.10 no.4
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• pp.207-211
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• 2007

The durable lifetime of RC structures is shortened by various reasons, which are the generation of cracks in construction and service term, the exterior deterioration according to climatic condition, the surface damage due to chloride attack and the corrosion of reinforced bars. The durability of concrete structures is nevertheless able to be increased by the method and the material of reinforcement and repair. The epoxy resin is widely used for reinforment and repair of concrete because of the superiority in mechanical property, adhesive property, abrasion resistance, impact resistance and chemical resistance. The epoxy cement mortar with hardening agent has a lot of disadvantages that are troublesome mixing work, weakened weatherability and high cost for hardening agent. In this study, the mix proportion of mortar is presented just only with epoxy resin and some admixtures, and the test result of mortar without hardening agent shows the higher strength than the mortar with hardening agent. In the mix proportion, the weight of epoxy resin must be less than 15% of the unit weight of cement, and 10% of unit weight of cement is adequate for the weight of admixtures.