• Journal of the Society of Naval Architects of Korea
• /
• v.54 no.2
• /
• pp.151-160
• /
• 2017

Growing demand and rapid development of the synthetic fiber rope in mooring system have taken place since it has been used in deep water platform lately. Unlike a chain mooring, synthetic fiber rope composed of lightweight materials such as Polyester(polyethylene terephthalate), HMPE(high modulus polyethylene) and Aramid(aromatic polyamide). Non-linear stiffness and another failure mode are distinct characteristics of synthetic fiber rope when compared to mooring chain. When these ropes are exposed to environmental load for a long time, the length of rope will be increased permanently. This is called 'the creep phenomenon'. Due to the phenomenon, The initial characteristics of mooring systems would be changed because the length and stiffness of the rope have been changed as time goes on. The changed characteristics of fiber rope cause different mooring tension and vessel offset compared to the initial design condition. Commercial mooring analysis software that widely used in industries is unable to take into account this phenomenon automatically. Even though the American Petroleum Institute (API) or other classification rules present some standard or criteria with respect to length and stiffness of a mooring line, simulation guide considers the mechanical properties that is not mentioned in such rules. In this paper, the effect of creep phenomenon in the fiber rope mooring system under specific environment condition is investigated. Desiged mooring system for a Mobile Offshore Drilling Unit(MODU) with HMPE rope which has the highest creep is analyzed in a time domain in order to investigate the effects creep phenomenon to vessel offset and mooring tension. We have developed a new procedure to an analysis of mooring system reflecting the creep phenomenon and it is validated through a time domain simulation using non-linear mooring analysis software, OrcaFlex. The result shows that the creep phenomenon should be considered in analysis procedure because it affects the length and stiffness of synthetic fiber rope in case of high water temperature and permanent mooring system.

• Journal of Korea Water Resources Association
• /
• v.47 no.11
• /
• pp.1051-1060
• /
• 2014

This study is attempted to realize an improved computation performance by combining the MPI (Message Passing Interface) Technique, a standard model of the parallel programming in the distributed memory environment, with the DHM(Diffusion Hydrodynamic Model), a inundation analysis model. With parallelizing inundation model, it compared with the existing calculation method about the results of applications to complicate and required long computing time problems. In addition, it attempted to prove the capability to estimate inundation extent, depth and speed-up computing time due to the flooding in protected lowlands and to validate the applicability of the parallel model to the actual flooding analysis by simulating based on various inundation scenarios. To verify the model developed in this study, it was applied to a hypothetical two-dimensional protected land and a real flooding case, and then actually verified the applicability of this model. As a result of this application, this model shows that the improvement effectiveness of calculation time is better up to the maximum of about 41% to 48% in using multi cores than a single core based on the same accuracy. The flood analysis model using the parallel technique in this study can be used for calculating flooding water depth, flooding areas, propagation speed of flooding waves, etc. with a shorter runtime with applying multi cores, and is expected to be actually used for promptly predicting real time flood forecasting and for drawing flood risk maps etc.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
• /
• 2002.08a
• /
• pp.54-63
• /
• 2002

Post-harvest technology for rice was focused on in-bin drying system, which consists of about 100, 000 facilities in 1980s. The modernized Rice Processing Complex (RPC) and Drying Storage Center (DSC) became popular for rice dry, storage, process and distribution from 1990s. However, the percentage of artificial drying for rice is 48% (2001) and the ability of bulk storage is about 15%. Therefore it is necessary to build enough drying and bulk storage facilities. The definition of high quality rice is to satisfy both good appearance and good taste. The index for good taste in rice is a below 7% of protein, 17-20% of amylose, 15.5-16.5% of moisture contents and high concentration of Mg and K. To obtain a high quality rice, it is absolutely needed to integrate high technologies including breeding program, cropping methods, harvesting time, drying, storing and processing methodologies. Generally, consumers prefer to rice retaining below b value of 5 in colorimetry, and the whiteness, the hardness and the moisture contents of rice are in order of consumer preference in rice quality. By selection of rice cultivars according to acceptable quality, the periods between harvesting time and drying reduced up to about 20 days. Therefore it is necessary to develop a low temperature grain drying system in order to (1) increase the rate of artificial rice drying up to 85%, (2) keep the drying temperature of below 45C, (3) maintain high quality in rice and (4) save energy consumption. Bulk storage facilities with low temperature storage system (7-15C) for rice using grain cooler should be built to reduce labor for handling and transportation and to keep a quality of rice. In the cooled rice, there is no loss of grain quality due to respiration, insect and microorganism, which results in high quality rice containing 16% of moisture contents all year round. In addition, introducing a low temperature milling system reduced the percentage of broken rice to 2% and increased the percentage of head rice to 3% because of proper hardness of grain. It has been noted that the broken rice and cracking reduced significantly by using low pressure milling and wet milling. Our mission for improving rice market competitiveness goes to (1) produce environment friendly, functional rice cultivars, (2) establish a grade standard of rice quality, (3) breed a new cultivar for consumer oriented and (4) extend the period of storage and shelf life of rice during postharvest.

• Journal of Korea Water Resources Association
• /
• v.53 no.11
• /
• pp.939-949
• /
• 2020

Currently, the demand for farmland is steadily decreasing due to changes in the agricultural environment and dietary life. In line with this, the government adopted an integrated water management with the enactment of the Framework Act on Water Management on June 2019. Therefore, it is required to take a closer look at agricultural water demand that accounts for 61% of water use for efficient water resources management. In this study, the overal process was evaluated for estimating agricultural water demand. More specifically, agricultural water demand for paddy field, which comprises 67% to 87% of agricultural water demand, was reviewed in detail. The biggest issue in estimating the paddy field water demand is the selection of the method for potential evapotranspiration. FAO recommends Penman-Monteith, but, currently, our criteria suggest a modified Penman equation that shows over estimation. Also, the crop coefficient, which is the main factor in evaluating evapotranspiration, has an issue that does not consider the current climate and crop varieties because it was developed 23 years ago. Comparing the Modified Penman and Penman-Monteith equations using the data from Jeonju National Weather Service, the modified Penman equation showed a big difference compared to the Penman-Monteith equation. When the crop coefficient was applied, the difference between late May and late August increased, where the amount of evapotranspiration was high. The estimation process was applied to four study reservoirs in Gimje. Comparing the estimated water demand with the supplied water record from reservoirs, the results showed that the estimation accuracy depends on not just the potential evapotranspiration, but also the standard water storing level in paddy fields.

• Journal of the Korea Institute of Building Construction
• /
• v.15 no.4
• /
• pp.359-365
• /
• 2015

Floor mortar experiences dry shrinkage by temperature and humidity difference of internal matrix with material type. Also, since floor mortar is influenced by environmental conditions during placing and curing period, cracks are likely to be occurred. In this study, it was evaluated the hardening and dry shrinkage properties of non-sintered binder based floor mortar utilizing alpha-hemihydrate gypsum which has expansibility in order to prevent crack of the floor mortar. It was applied to the construction site, and examined the effects of external environmental conditions on shrinkage deformation and cracking. Different types of slag accelerated initial and final setting in comparison with cement mortar and its compressive strength was satisfied standard compressive strength for floor mortar. Also shrinkage deformation behavior after the initial expansion exhibited a similar tendency with the cement mortar. From the field application result, no crack was found from slag mortar, and it is determined that the slag mortar has better dimensional stability than cement mortar caused by external environment conditions.

• Physical Therapy Korea
• /
• v.14 no.3
• /
• pp.48-56
• /
• 2007

Environmental Enrichment (EE) alone is not capable of enhancing the fine digit and the forelimb functions. Therefore, we applied modified constraint-induced movement therapy (mCIMT) under the influence of EE to assess its effect on promoting improved forelimb sensorimotor functions. Focal ischemic brain injury was produced in Sprague-Dawley rats (60 rats, $250{\pm}50$ g) through middle cerebral artery occlusion (MCAO). Before MCAO induction, all rats were trained in modified limb placing tests and reaching tasks for 1 week. Then they were randomly divided into three groups: Group I: application of standard environment (SE) after MCAO induction (n=20), Group II: application of EE after MCAO induction (n=20), Group III: MCAO+EE, mCIMT and task-oriented training that was initiated at 10th day after MCAO induction (n=20). We also applied mCIMT (between 9 AM and 5 PM/daily) which included restraining the forelimb ipsilateral to the lesion using the 'Jones & Schallert' method. We assessed the change of modified limb placing, single pellet reaching test and the immunoreactivity of BDNF by immunohistochemistry (pre, 1st, 5th, 10th and 20th day). Group I showed no improved outcome, whereas group II and III significantly improved on the use of the forelimb and the immunoreactivity. The qualitative analysis of the skilled reaching test, of group III showed the greatest improvement in the fine digit and the forelimb function. These results suggest that EE combined with mCIMT is more functional in promoting enhanced fine digit and forelimb functional movements.

• The Journal of Korean society of community based occupational therapy
• /
• v.5 no.1
• /
• pp.55-62
• /
• 2015

Objective : The purpose of this study was to investigate the satisfaction of occupational therapy service for parents of children with disabilities using specialized child-care centers for disabled in Gyeongbuk. Methods : The subjects of this study were 104 parents who have experience in occupational therapy at 14 specialized child-care centers for disabled in Gyeongbuk. A questionnaire was conducted from July, 2014 to March, 2015. Descriptive statistics of frequency, mean, standard deviation, and One-Way ANOVA study were used to analyze data. Results : Disabled children got occupational therapy at first when they were 3.25 years, on average. Duration of occupational therapy use were 31.84 month, on average. The subjects determined to got occupational therapy mostly through consultation nurseries(40.4%). Most of them got speech therapy(78.0%) other than receiving occupational therapy service, responded very necessary to occupational therapy(69.3%). Satisfaction of occupational therapy service were 4.49 point at attitude of occupational therapists, 4.36 point at occupational therapy program, and 4.26 point at environment of occupational therapy room. Attitude of occupational therapists were the highest satisfied. Conclusion : This study would contribute to effective and meaningful occupational therapy through objective view

• Korean Journal of Construction Engineering and Management
• /
• v.8 no.4
• /
• pp.73-80
• /
• 2007

As BTL(Build-Transfer-Lease) private investment business benchmarking PHI(Private Finance Initiative) of USA and Japan is introduces to Korea since 2005, as a part of supplying high leveled public service and early expanding required facilities for SOC, Value for Money on private investment business from treasury investment business at the beginning gets to be needed. Accordingly, this survey has been conducted in order to analyse BTL projects status, propriety of economic analysis method(VFM analysis, calculation of estimated business expenses, valuation of bidding price, etc.) by business advance phases from the viewpoint of person in charge, necessity of improvement and alternative plants. As the result of conducting cross tabulation analysis and correlation analysis by occupational group, BTL project advance phases and alternative plans for improvement, it is necessary ye prepare standardized service level against business expense and basis for calculating and evaluation operation expenses. Based on the necessity of quantitative analysis (LCC analysis) of VFM, standard for calculating management, maintenance and administration expenses is required. In addition, reliable economic valuation system considering domestic BTL environment should be setup, for business efficiency.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• 2007.11a
• /
• pp.190-196
• /
• 2007

As the number of aged-housing has been rapidly increased, many kinds of defects and problems such as degeneration of housing environment, structural performance, and equipment performance have been appeared. The reconstruction as the way to improve the aged-housing has been used mostly because the legal process of the reconstruction is relatively easy. On the other hand, it has caused problems such as the lack of natural aggregates, the environmental damages owing to construction wastes, the loss of national resources, and the lack of the housing for rent nearby the reconstruction area. This problems limit active tying into the reconstruction business at present in the industrial and political perspective. In this context, it is necessary to revitalize the remodeling rather than the reconstruction. In order to reach this objective, this research aims at identifying the user-oriented performance for the housing and deducing the core technology. It is expected that the result of this research can contribute to more revitalize the remodeling as tying researches in terms of design, structure, equipment, and construction.

• Journal of Environmental Policy
• /
• v.7 no.4
• /
• pp.1-34
• /
• 2008

It is recognized that RPS(Renewable Portfolio Standard) and FIT(Feed-in Tariff) are two main policy instruments to promote Renewable Electricity(RE). The Korean Government announced in 2008 that RE promotion scheme will be changed to RPS from current FIT system in 2012. But we believe RPS is inferior to FIT for promoting less developed technologies such as photovoltaics or wind power. This is because the achievement of RE promotion in countries adopting RPS is markedly worse than that in European counties or Janpan adopting FIT. If the policy change is inevitable, when considering the lessons from Japan's failure as well as supporting the less developed technologies, it is recommended that either the market should be divided into several technology and scale categories, or more RPS-Credit per kWh should be assigned to the photovoltaic and wind power than instead of letting the all technologies compete in the "open category". It is also recommended that (1) Renewable Energy Promotion Fund(tentative name) based on a part of current energy related tax revenue should be introduced, or (2) cost of supporting the Renewable Electricity should automatically be transferred into the electricity bill of electricity consumers following the German System.