• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.12
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• pp.157-164
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• 2019

Superabsorbent polymers(SAPs) are powdery material that absorb water several tens or hundreds of times its own mass. It has been reported that when SAPs are incorporated into a high strength cementitious material, the autogenous shrinkage of the material is reduced. Cross-linked sodium polyacrylate type SAPs are relatively safe for human body and low in production cost. In order to apply this type of SAPs to the admixture for total(plastic+autogenous+drying) shrinkage reduction of high strength mortar, the shrinkage behavior of mortar when an expansion agent(EA) and SAPs were mixed together was analyzed. As a result, it was found that the shrinkage was reduced when an EA 5% (mass % of cement) and SAPs 0.4% were mixed together than the mortar containing only an EA 10%. The shrinkage was further reduced when EA 10% and SAPs 0.4% were incorporated into mortar.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.3
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• pp.47-56
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• 2016

Superabsorbent Polymers (SAPs) are hydrophilic synthetic polymers which could absorb water by hundreds of their own weight. They are used for multiple purpose including hygienic goods, soil conditioners, and hospital supplies. It is necessary to investigate the standard of their use including the amendment rate for soil application in agricultural fields. It is also important to understand their effects on the soil water content and engineering characteristics. The objective of this study is to find the water absorbing capacity and reusability of SAPs, and the characteristics of water release and effect of them on soil water content and engineering characteristics. In the result, SAPs per unit weight (1 g) used for this research could absorb about 200 g of water in max. The water absorbing capacity decreased after SAPs were used repeatedly. Released water of SAPs could provide the soils with about 9 % of the soil water content. Soil water content increased with decreasing distance from the SAPs. The distance of release was spreaded out with increasing water absorbed of SAPs. Finally, when a drainage and the capacity of soil water content were considered, it is recommended to amend the SAPs with soil by less than 0.25 %.

• Journal of Preventive Medicine and Public Health
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• v.38 no.3
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• pp.276-282
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• 2005

Objectives : To evaluate the predictive validity of three scoring systems; the acute physiology and chronic health evaluation(APACHE) III, simplified acute physiology score(SAPS) II, and mortality probability model(MPM) II systems in critically ill patients. Methods : A concurrent and retrospective study conducted by collecting data on consecutive patients admitted to the intensive care unit(ICU) including surgical, medical and coronary care unit between January 1, 2004, and March 31, 2004. Data were collected on 348 patients consecutively admitted to the ICU(aged 16 years or older, no transfer, ICU stay at least 8 hours). Three models were analyzed using logistic regression. Discrimination was assessed using receiver operating characteristic(ROC) curves, sensitivity, specificity, and correct classification rate. Calibration was assessed using the Lemeshow-Hosmer goodness of fit H-statistic. Results : For the APACHE III, SAPS II and MPM II systems, the area under the receiver operating characterist ic(ROC) curves were 0.981, 0.978, and 0.941 respectively. With a predicted risk of 0.5, the sensitivities for the APACHE III, SAPS II, and MPM II systems were 81.1, 79.2 and 71.7%, the specificities 98.3, 98.6, and 98.3%, and the correct classification rates 95.7, 95.7, and 94.3%, respectively. The SAPS II and APACHE III systems showed good calibrations(chi-squared H=2.5838 p=0.9577 for SAPS II, and chi-squared H=4.3761 p=0.8217 for APACHE III). Conclusions : The APACHE III and SAPS II systems have excellent powers of mortality prediction, and calibration, and can be useful tools for the quality assessment of intensive care units(ICUs).

• Journal of Korean Academy of Nursing
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• v.49 no.5
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• pp.550-561
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• 2019

Purpose: This study aimed to identify the effects of utilizing Smartphone Application Peer Support (SAPS) on health behavior and body mass index (BMI) among overweight or obese breast cancer survivors (BCS). Methods: A nonequivalent control group with a non-synchronized design was utilized and 36 participants (experimental group 14, control group 22) were recruited from August 2017 to September 2018. Participants were 40~65 years old, overweight or obese, had completed primary cancer treatment within the 12 months prior to the study, and had not done regular exercise during the last 6 months. The 3-month SAPS consisted of exercise and diet education (once p/2 weeks), peer support (once p/week), and self-monitoring using smartphone applications (5 times p/week). All participants underwent assessments at baseline, right after SAPS, and at 3 months after SAPS. Data were analyzed using repeated measures ANOVA. Results: At the completion of SAPS significant differences were found between groups in motivation for exercise (t=-3.24, p=.005), physical activity (t=-4.15, p<.001), total calorie intake (t=3.42, p=.002), calories from fat (t=-3.01, p=.005), intake of vegetables (t=-2.83, p=.008), and BMI (t=5.21, p<.001). Significant differences in BMI (t=4.13, p<.001) remained up to 3 months after SAPS completion. No significant differences was shown between groups in self-efficacy for exercise, either immediately after or 3 months after SAPS. Conclusion: The SAPS has the potential to improve motivation for exercise, health behavior, and BMI of BCS. However, special efforts are required to encourage participants to complete the intervention and maintain long-term effects for future trials.

• Korean Journal of Community Nutrition
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• v.17 no.3
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• pp.312-320
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• 2012

The purpose of this study was to investigate the perception of the school dietitian on superior agricultural products (SAP) and the status of using superior agricultural products in school meals. Questionnaires were distributed to 185 school dietitians after face to face interview, and a total of 181 responses were used for analysis. 82.3% of the respondents were using SAPs in school meals and there was a significant difference between elementary school (95.1%), middle school (76.8%) and high school (66.7%) dietitians (p < 0.001). 85.2% of the dietitians, who were using SAP, were purchasing SAPs through electronic bidding, and the main reason of not using SAPs was the higher price of SAPs than that of general agricultural products. The good agricultural practices (GAP) product was considered the most appropriate agricultural products for school meals by the majority of respondents (66.9%), and organic products was the next (13.3%). In addition, the most important selection criterion for a SAP perceived by school dietitians was safety (58.0%), and the main reason of using SAPs in school meals, when two choices were allowed, was 'to provide healthful food to children' (98.9%). The major barriers to using SAPs in school meals (two choices were allowed) were 'too expensive' (73.5%) and 'unstable supply' (32.6). In conclusion, it was suggested that there should be an improvement in SAP supply and management systems to increase the use of SAPs in school meals.

• Journal of Internet Computing and Services
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• v.18 no.6
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• pp.7-13
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• 2017

In this paper, we propose a novel dynamic subchannel grouping (DSG) algorithm to maximize the system capacity considering intended proper outage probability for the downlink of enterprise small-cell networks (ESNs). In the proposed DSG scheme, a local gateway (LGW) which is installed in a building dynamically divides the frequency bandwidth into different numbers of subchannel groups (SGs) based on the numbers of small-cell access points (SAPs) and small-cell user equipments (SUEs) per floor. Then, the LGW assigns the SGs to SAPs and the SAPs allocate them to their serving SUEs. Through simulation results, we show that the proposed DSG scheme is appropriate for the ESNs compared to the conventional small-cell networks in which all SAPs use the number of fixed SGs in terms of the system capacity and outage probability.

• Journal of the Korean Wood Science and Technology
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• v.26 no.3
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• pp.81-92
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• 1998

Lately public interest in tree saps of maple and birch trees has been increased for sap drink as a natural medical beverage. To ensure tree sap drink for commercial production, species which are available in resources, their ecological regeneration characteristics in the natural forest stand, and tree sap resources should be investigated. Species for the collecting tree saps and their distribution were surveyed in the areas of Mt.Sobaek, Tanyang-gun, Chungcheongbuk-do. Mt.Sobaek area was selected to the proper place to survey as the feasible area for tapping tree saps for the natural beverage. Feasible tree species of this area are Betula costata, Betula schmidtii, Comus controversa, Acer mono, and Acer pseudosieboldianum based on the estimated tree sap amounts. Average and maximum species diversities of surveyed area were 4.2 and 5.39, respectively. Its evenness 0.78 referred that there are actively progressing ecological regeneration among diverse tree species. Tree saps are mainly harvested at the areas of upper and lower Wonmanteo. In terms of species, the most high sap amounts were from birch sap, next Comus controversa, the 3rd Acer mono. Many measures were suggested ecologically and technically, for commercial or practical production of tree sap drinks, though Mt.Sobaek area was evaluated as improper place because of geographical and transportational limitation.

• Journal of the Korean Wood Science and Technology
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• v.26 no.3
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• pp.93-99
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• 1998

Lately public interest in tree saps of maple and birch trees stimulated to increase demands for sap drink as a natural medical beverage. In order to understand factors affecting tree sap flows, birch species, particularly Betula platyphylla in Mt.Sobaek area, were monitored for daily sap flows according to factors, such as DBH, tapping hole sizes and direction of hole drilling on the trunks. The chemical constituents of saps were also analyzed. The sap flow initiated from the end of March and finished at the end of April. The flow maxima appeared from April 14th to April 26th. Total amounts of the sap flow obtained from birch tree were over 1,800 ml per day per one tree. Sap flows were increased with increasing DBH and tree age. Six milimeter drilled hole resulted in the highest sap flows. Sap flows increased with increases of diameter and height of the trees. Hole drilling to downward side(south-facing) of tree produced almost doubled sap flows than that of upward one(north-facing), while rightside drilling produced same amounts of saps to that of leftside one. Six mm drilling gave the best results not only in maximum flows but also effective hole occluding rates. The saps have in the range of 4.5 to 5.6 pH and l.0 - 2.0% of saccharinity. Sucrose, glucose, fructose and high mineral contents were found in the saps of birch tree. The tree saps could be utilized not only medicinal drink, but also one of the healthy beverages.

• Korean Journal of Environmental Agriculture
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• v.42 no.1
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• pp.1-7
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• 2023

Super absorbent polymers (SAPs) are hydrophilic molecules that can absorb large amounts of water. This study was conducted to investigate the enhancement of the physicochemical properties of sand soil blended with three SAPs imbibed with 100, 150, and 200-fold water. Three treatments were applied, namely, 100SAP, 150SAP, and 200SAP. The three SAPs were blended at concentrations of 0% (control), 3%, 5%, 7%, and 10% with sand. The pH, electrical conductivity, and cation exchangeable capacity (CEC) of soil blended with the three SAPs were pH 6.35-6.46, 0.09-0.65 dS/m, and 1.42-1.92 cmol_c/kg, respectively, and their capillary porosity, total porosity, and saturated hydraulic conductivity were 21.0-29.3%, 39.2-48.7%, and 272-470 mm/hr. CEC, capillary porosity, total porosity, and saturated hydraulic conductivity of soil were positively correlated with the ratio of the SAPs (p<0.01). These results indicate that blending sand soil with SAPs increased CEC, capillary porosity, and saturated hydraulic conductivity, thus improving the nutrient-retention capacity, water-retention capacity, and permeability of the soil.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.1
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• pp.88-96
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• 2020

In this study, the effect of cyclic wetting-drying on the self-healing of cementitious materials containing superabsorbent polymers (SAPs) were experimentally evaluated. In each cycle, cracked cement paste specimens containing various SAP dosages were exposed to wet conditions for 1 h, during which the capillary water absorption tests and water flow tests were conducted, and then exposed to dry conditions for 47 h. The capillary water absorption test results showed that the sorptivity values of the specimen without SAPs, SAP 0.5%, SAP 1.0%, and SAP 1.5% specimens were decreased by approximately 22.9%, 36.8%, 42.8%, and 46.3%, respectively, after 8 cycles. In addition, the water flow test results showed that the amount of water runoff through the cracks of all cracked specimens gradually decreased over wet/dry cycles, especially the reduction ratio of the amount of water runoff increased with increasing SAP dosage. Furthermore, the swelling behavior of SAPs in cracks by in gress water was con firmed via X-ray computed tomography (CT) analysis. These results indicate that the effective crack width can be reduced as SAPs absorb water and swell, while the water absorbed in SAPs can be released to crack surfaces under dry conditions, further promoting healing product formation. This study demon strates that the in corporation of SAPs can in crease the water tightness of cracks, thereby improving the self-healing efficiency of cementitious materials.