• Journal of Construction Engineering and Project Management
• /
• v.5 no.2
• /
• pp.11-15
• /
• 2015

The Last PlannerSystem (LPS) has been implemented on construction projects to increase work flow reliability, a precondition for project performance againstproductivity and progress targets. The LPS encompasses four tiers of planning processes:master scheduling, phase scheduling, lookahead planning, and commitment / weeklywork planning. This research highlights deficiencies in the current implementation of LPS including poor lookahead planning which results in poor linkage between weeklywork plans and the master schedule. This poor linkage undetermines the ability of theweekly work planning process to select for execution tasks that are critical to projectsuccess. As a result, percent plan complete (PPC) becomes a weak indicator of project progress. The purpose of this research is to improve lookahead planning (the bridgebetween weekly work planning and master scheduling), improve PPC, and improve theselection of tasks that are critical to project success by increasing the link betweenShould, Can, Will, and Did (components of the LPS), thereby rendering PPC a betterindicator of project progress. The research employs the case study research method to describe deficiencies inthe current implementation of the LPS and suggest guidelines for a better application ofLPS in general and lookahead planning in particular. It then introduces an analyticalsimulation model to analyze the lookahead planning process. This is done by examining the impact on PPC of increasing two lookahead planning performance metrics: tasksanticipated (TA) and tasks made ready (TMR). Finally, the research investigates theimportance of the lookahead planning functions: identification and removal ofconstraints, task breakdown, and operations design.The research findings confirm the positive impact of improving lookaheadplanning (i.e., TA and TMR) on PPC. It also recognizes the need to perform lookaheadplanning differently for three types of work involving different levels of uncertainty:stable work, medium uncertainty work, and highly emergent work.The research confirms the LPS rules for practice and specifically the need to planin greater detail as time gets closer to performing the work. It highlights the role of LPSas a production system that incorporates deliberate planning (predetermined andoptimized) and situated planning (flexible and adaptive). Finally, the research presents recommendations for production planningimprovements in three areas: process related, (suggesting guidelines for practice),technical, (highlighting issues with current software programs and advocating theinclusion of collaborative planning capability), and organizational improvements(suggesting transitional steps when applying the LPS).

• Journal of Korea Water Resources Association
• /
• v.31 no.6
• /
• pp.821-832
• /
• 1998

This study investigates the prediction of daily water supply, which is a necessary for the efficient management of water distribution system. Fuzzy neuron, namely artificial intelligence, is a neural network into which fuzzy information is inputted and then processed. In this study, daily water supply was predicted through an adaptive learning method by which a membership function and fuzzy rules were adapted for daily water supply prediction. This study was investigated methods for predicting water supply based on data about the amount of water supplied to the city of Kwangju. For variables choice, four analyses of input data were conducted: correlation analysis, autocorrelation analysis, partial autocorrelation analysis, and cross-correlation analysis. Input variables were (a) the amount of water supplied (b) the mean temperature, and (c)the population of the area supplied with water. Variables were combined in an integrated model. Data of the amount of daily water supply only was modelled and its validity was verified in the case that the meteorological office of weather forecast is not always reliable. Proposed models include accidental cases such as a suspension of water supply. The maximum error rate between the estimation of the model and the actual measurement was 18.35% and the average error was lower than 2.36%. The model is expected to be a real-time estimation of the operational control of water works and water/drain pipes.

• Food Science and Preservation
• /
• v.24 no.7
• /
• pp.1034-1042
• /
• 2017

The quality characteristics of Yakju and survival rate of yeast were investigated by modifying the drying method for the cold adapted yeast strain Saccharomyces cerevisiae Y297 (SCY297). Viability and fermentation characteristics of the freeze-dried, air blast-dried, and liquid SCY297 cultures were compared after storing them at $25^{\circ}C$. In addition, 5% skimmed milk, ${\alpha}$-lactose, or trehalose was added as a protective agent for examining the effects of drying methods. During the 15-week storage period, the liquid and freeze-dried SCY297 cultures containing a protective agent showed a survival rate of 80%. However, the air blast-dried SCY297 culture showed 80% survival rate only in the skimmed milk supplemented group. Compared to the untreated cells, the acidity and amino acidity of Yakju prepared using freeze-dried or air blast-dried cultures of SCY297 increased by 2 fold and 5.7 fold respectively, while the alcohol content decreased by 5.07%. Compared to the untreated cells, the pH and amino acidity of Yakju prepared using the liquid culture of SCY297 increased by 1.5 fold and 2.5 fold respectively. Although the alcohol content decreased by 2.9%, decrease rate was lower than that observed for the freeze-dried and air blast-dried yeast cultures. Therefore, the results of this study showed that using a liquid starter culture was more advantageous than using the conventional solid culture.

• The Korean Journal of Food And Nutrition
• /
• v.29 no.3
• /
• pp.431-437
• /
• 2016

Macrophages play a pivotal role in the innate and adaptive immune systems. This study investigated the immuno-modulatory activities of polysaccharides separated from Chrysanthemum zawadskii var. latilobum (CZPS) in macrophages. Polysaccharides from Chrysanthemum zawadskii var. latilobum were extracted by the ethanol precipitation method. RAW 264.7 mouse macrophage cell line was treated with CZPS (4 to $128{\mu}g/mL$), and there was no cytotoxicity at a dose below $32{\mu}g/mL$. The levels of nitric oxide (NO) and pro-inflammatory cytokines (tumor necrosis factor (TNF)-${\alpha}$ and interleukin (IL)-6, IL-$1{\beta}$) production in the CZPS treated group ($32{\mu}g/mL$) were $6.5{\pm}0.12{\mu}m$ (NO), $1252.8{\pm}79.85$ (TNF-${\alpha}$), $305.4{\pm}29.41$ (IL-6), and $683.3{\pm}59.71$ (IL-$1{\beta}$), respectively, and they were significantly increased when compared to the control group; $2.2{\pm}0.03{\mu}m$ (NO), $452.3{\pm}38.34$ (TNF-${\alpha}$), $31.7{\pm}5.75$ (IL-6), and $184.1{\pm}11.52$ (IL-$1{\beta}$). Additionally, protein expression of inducible nitric oxide synthase (iNOS) and phosphorylation of MAPKs and NF-${\kappa}B$ expression were significantly increased upon CZPS treatment. Therefore, these results indicated that polysaccharides separated from Chrysanthemum zawadskii var. latilobum (CZPS) may have a potential immunomodulatory activity in macrophages through MAPKs and NF-${\kappa}B$ signaling, and this information is useful for the development of immune enhancing adjuvant materials using a natural ingredient.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.50 no.11
• /
• pp.58-63
• /
• 2013

This paper presents a transceiver design for DisplayPort interface using an optical channel. By converting the electronic channel to the optical channel, the DisplayPort's main channel can provide a high-speed data transmission for long distance. The design converting the electronic channel to the optical channel in the main channel and AUX channel of the DisplayPort is presented in this paper. Futhermore, the HPD signal transmission by using AUX channel is proposed. In order to minimize power consumption, this paper also proposed a method of controlling the TX block in the main link. The proposed system is designed by a FPGA and an optical module. The FPGA used 651 ALUT(adaptive look-up table)s, 511 resisters and 324 block memory bits. The maximum operating rate of the FPGA is 250MHz. With the proposed power control scheme, 740mW of power dissipation reduction can be achieved at the main link optical TX module.

• Journal of Korea Water Resources Association
• /
• v.46 no.6
• /
• pp.655-666
• /
• 2013

Lately, intensity and frequency of natural disasters such as flood are increasing because of abnormal climate. Casualties and property damages due to large-scale floods such as Typhoon Rusa in 2002 and Typhoon Maemi in 2003 rapidly increased, and these show the limits of the existing disaster prevention measures and flood forecasting systems regarding irregular climate changes. In order to efficiently respond to extraordinary flood, it is important to provide effective countermeasures through an inundation model that can accurately simulate flood inundation patterns. However, the existing flood inundation analysis model has problems such as excessive take of analysis time and accuracy of the analyzed results. Therefore, this study conducted a flood inundation analysis by using the Gerris flow solver that uses quadtree grid, targeting the Baeksan Levee in the Nakdong River Basin that collapsed because of a concentrated torrential rainfall in August, 2002. Through comparisons with the FLUMEN model that uses unstructured grid among the existing flood inundation models and the actual flooded areas, it determined the applicability and efficiency of the quadtree grid-based flood inundation model of the Gerris flow solver.

• The Korean Journal of Ecology
• /
• v.28 no.6
• /
• pp.395-404
• /
• 2005

A project has recently begun to reintroduce endangered Asiatic black bears to the Jirisan National Park. However, information on home range that is necessary to maintain the Minimum Viable Population (MVP) of those bears does not exist. Based on point data of two bears that were released for trial in Jirisan in 2001, we identified the movement pattern of bears and estimated their home ranges with two different methods Finally, the possibility of conserving the MVP of bears was evaluated by comparing the location and size of the home range with habitats which have been found to be suitable for bears. The frequency of bears' appearance reduced drastically as road densities of both paved roads and legal trails increased. The midpoint of home ranges of the two bears was 376.85 $km^2$ and 50.76 $km^2$ based on 100% MCP (Minimum Convex Polygon) and 95% AK (Adaptive Kernel Home Range Method), respectively, with an overlapped area of 126.0 $km^2$ and 3.99 $km^2$ each. The core areas of their home ranges are located not in the no-entry zone, where major trails were open to the public - despite being designated as no -entry zone - but in areas where most trails were closed to the public. A discrepancy between core areas of home ranges and potentially suitable habitats suggests the effects of vehicles and tracking people through roads within the park. Thus, for the success of in situ conservation of endangered bears, well-planned management of habitats is needed to protect bears and to ensure the home ranges to support the MVP.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.40 no.1
• /
• pp.96-107
• /
• 2015

VANET technologies provide real-time traffic information for mitigating traffic jam and preventing traffic accidents, as well as in-vehicle infotainment service through Telematics/Intelligent Transportation System (ITS). Due to the rapid increasement of various requirements, the vehicle communication with a limited resource and the fixed frame architecture of the conventional techniques is limited to provide an efficient communication service. Therefore, a new flexible operation depending on the surrounding situation information is required that needs an adaptive design of the network architecture and protocol for efficiently predicting, distributing and sharing the context-aware information. In this paper, Vehicle-to-Infrastructure (V2I) based on communication between vehicle and a Road Side Units (RSU) and Vehicle-to-Vehicle (V2V) based on communication between vehicles are effectively combined in a new MAC architecture and V2I and V2V vehicles collaborate in management. As a result, many vehicles and RSU can use more efficiently the resource and send data rapidly. The simulation results show that the proposed method can achieve high resource utilization in accordance. Also we can find out the optimal transmission relay time and 2nd relay vehicle selection probability value to spread out V2V/V2I collaborative schedule message rapidly.

• Journal of Broadcast Engineering
• /
• v.10 no.3
• /
• pp.270-285
• /
• 2005

A joint design scheme is proposed to optimize the up/down scaler and the motion vector estimation module in the transcoder system. The proposed scheme first optimizes the resolution scaler for a fixed motion vector, and then a new motion vector is estimated for the fixed scaler. These two steps are iteratively repeated until they reach a local optimum solution. In the optimization of the scaler, we derive an adaptive version of a cubic convolution interpolator to enlarge or reduce digital images by arbitrary scaling factors. The adaptation is performed at each macroblock of an image. In order to estimate the optimal motion vector, a temporary motion vector is composed from the given motion vectors. Then the motion vector is refined over a narrow search range. It is well-known that this refinement scheme provides the comparable performance compared to the full search method. Simulation results show that a jointly optimized system based on the proposed algorithms outperforms the conventional systems. We can also see that the algorithms exhibit significant improvement in the minimization of information loss compared with other techniques.

• Journal of Broadcast Engineering
• /
• v.15 no.1
• /
• pp.122-132
• /
• 2010

AT-DMB system has been developed to increase data rate up to double of conventional T-DMB in the same bandwidth while maintaining backward compatibility. The AT-DMB system adopted hierarchical modulation which adds BPSK or QPSK signal as enhancement layer to existing DQPSK signal. The enhancement layer signal should be small enough to maintain backward compatibility and to minimize the coverage loss of conventional T-DMB service coverage. But this causes the enhancement layer signal of AT-DMB susceptible to fading effect in transmission channel. A turbo code which has improved error correction capability than convolutional code, is applied to the enhancement layer signal of the AT-DMB system for compensating channel distortion. However there is a need for other solutions for better reception of AT-DMB signal in receiver side without increasing transmitting power. In this paper, we propose adaptive array antenna system with Eigen-space beamforming algorithm which benefits beamforming gain along with diversity gain. We analyzed the reception performances of AT-DMB system in indoor and mobile environments when this new smart antenna system and algorithm is introduced. The computer simulation results are presented along with analysis comments.