• Journal of IKEEE
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• v.11 no.4
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• pp.322-330
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• 2007

Recent advances in wireless networks and low-cost, low-power design have led to active research in large-scale networks of small, wireless, low power sensors and actuators, In large-scale networks, lots of timing-synchronization protocols already exist (such as NTP, GPS), In ad-hoc networks, especially wireless sensor networks, it is hard to synchronize all nodes in networks because it has no infrastructure. In addition, sensor nodes have low-power CPU (it cannot perform the complex computation), low batteries, and even they have to have active and inactive section by periods. Therefore, new approach to time synchronization is needed for wireless sensor networks, In this paper, I propose Energy-Efficient Time Synchronization (EETS) protocol providing network-wide time synchronization in wireless sensor networks, The algorithm is organized two phase, In first phase, I make a hierarchical tree with sensor nodes by broadcasting "Level Discovery" packet. In second phase, I synchronize them by exchanging time stamp packets, And I also consider send time, access time and propagation time. I have shown the performance of EETS comparing Timing-sync Protocol for Sensor Networks (TPSN) and Reference Broadcast Synchronization (RBS) about energy efficiency and time synchronization accuracy using NESLsim.

• Journal of Korean Society on Water Environment
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• v.30 no.3
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• pp.292-297
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• 2014

We synthesized the self-organized nanoporous oxide with potentiostatic anodization of iron foil. The iron oxide nanocomposite (INCs) were fabricated in 1M $Na_2SO_4$ containing 0.5wt% NaF electrolyte holding the potential at 20, 40 and 60 V for 20min, respectively. Field Emmision Scanning Electron Microscopy (FESEM) and X-ray Diffractometer (XRD) were used to evaluate the micromorphology and crystalline structure of INC film. Also, this study was performed to evaluate the fenton reaction using INC film with hydroperoxide for degradation of cyanide dissolved in water. In case of INC-40V in the presence of $H_2O_2$ 3%, the first-order rate constant was found to be $1.7{\times}10^{-2}min^{-1}$, and indicated to be $1.2{\times}10^{-2}min^{-1}$ on commercial hematite powder. This result is shown to be good performance enough to replace the powder type for treatment of wastewater.

• Journal of the Korean Home Economics Association
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• v.42 no.12 s.202
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• pp.175-190
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• 2004

The purposed of this research was to suggest a basic material of Korean-typed cohousing plan for a dual-income family by examining the difference of cohousing residing environment needs. Selecting Employed and unemployed housewives as this research's subject, the following results were drawn from the analysis between the two groups. 1) The housewives takes responsibility of the household works regardless of whether or not they are employed. Also, more than half of employed housewives stated that the time of nursery facilities was shorter than their needs and that they favored a nursery facility located inside the residential area. 2) The most meaningful difference of cohousing residing environment needs was the demand for sharing household work in terms of cohousing need of the subjects. The desirable cohousing area is the suburbs of the metropolitan areas and the preferable resident organization is need to be organized by people sharing the same goal through an announcement. 3) The need of cohousing and residence intention were generally low, but the employed housewives' need was higher than the unemployed ones.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.8
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• pp.1162-1172
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• 2000

The research was conducted to quantify farm and household characteristics of sheep farmers, evaluate farmer access to and the effectiveness of livestock services in sheep farming areas, and examine regional constraints to improving sheep productivity and profitability in Nepal. A rapid diagnostic socioeconomic survey of 200 sheep farmers was carried out in 1996 and all four ecological regions (Trans-Himalayan, Mountains, Hills and Terai), each with a distinct local sheep breed, were represented in the survey. Six major constraints were identified: (a) poor performance of local sheep breeds, (b) a serious seasonal deficit of pasture and other feed, (c) the lack of an organized market for wool and meat, (d) poor access to agricultural credit, (e) primitive shearing equipment, and (f) an inadequate supply of drinking water for sheep. Strategies to assist farmers develop their sheep management skills, improve access and quality of support services, improved technology adaptable to local conditions and effective linkages with local carpet and meat industry are likely to overcome the constraints and alleviate persistent poverty faced by sheep farmers in Nepal.

• Korean Journal of Adult Nursing
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• v.22 no.4
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• pp.408-417
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• 2010

Purpose: The purpose of this study was to describe public health services for the aged in public health centers from the perspective of public health nurses. Methods: The interview data were collected from 11 public health nurses and analyzed by using Colazzi's (1978) descriptive phenomenology. The procedural steps was that described the phenomenon of interest, collected participants' descriptions of the phenomenon, extracted the meaning of significant statement, organized the meanings into theme clusters, wrote exhaustive descriptions and then incorporated data into an exhaustive description. Results: The results included 291 re-statements, 49 constructed meanings, 27 themes, 12 theme clusters, and 5 categories were deduced. The five categories were 'perception of obstacles for elderly health system', 'sense of burden in services of health', 'planning about diverse elderly health services', 'elderly clients-focused performance', and 'solidify community ground of elderly health services'. Despite obstacles, participants tried to diverse health services for elderly. Conclusion: This study has described public health nurses' experiences about public health services for the aged. These findings have important implication for the practice of public health services for the aged and must be considered to develop program for planning and practice of public health nurses for the aged.

• Journal of Mechanical Science and Technology
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• v.18 no.1
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• pp.92-105
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• 2004

A new algorithm for planning a collision-free path based on algebraic curve is developed and the concept of collision-free Path Space (PS) is introduced. This paper presents a Geometry Mapping (GM) based on two straight curves in which the intermediate connection point is organized in elliptic locus ($\delta$, $\theta$). The GM produces two-dimensional PS that is used to create the shortest collision-free path. The elliptic locus of intermediate connection point has a special property in that the total distance between the focus points through a point on ellipse is the same regardless of the location of the intermediate connection point on the ellipse. Since the radial distance, a, represents the total length of the path, the collision-free path can be found as the GM proceeds from $\delta$=0 (the direct path) to $\delta$=$\delta$$\_$max/(the longest path) resulting in the minimum time search. The GM of elliptic workspace (EWS) requires calculation of interference in circumferential direction only. The procedure for GM includes categorization of obstacles to .educe necessary calculation. A GM based on rectangular workspace (RWS) using Cartesian coordinate is also considered to show yet another possible GM. The transformations of PS among Circular Workspace Geometry Mapping (CWS GM) , Elliptic Workspace Geometry Mapping (EWS GM) , and Rectangular Workspace Geometry Mapping (RWS GM), are also considered. The simulations for the EWS GM on various computer systems are carried out to measure performance of algorithm and the results are presented.

• Journal of the Korean Institute of Intelligent Systems
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• v.26 no.5
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• pp.390-395
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• 2016

In this paper, a sprint race of human and that of humanoid robot are compared. Sprint race is one of the most popular sports games of human. HuroCup organized by FIRA is the most representative sports event of humanoid robots. The rules of the sprint race in HuroCup are explained and the strategy for the sprint race that humanoid robots can play is proposed. A child-sized humanoid robot is designed and developed so that it can play to follow the rules of the sprint race. The algorithm of the game strategy is applied to the robot, and the robot's performance is tested. Eventually, in HuroCup, it is verified that the developed humanoid robot is suitable to perform the sprint race.

• The Journal of Information Systems
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• v.15 no.2
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• pp.247-270
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• 2006

This study identifies communication patterns of groups using Instant Messenger for their group decision-making, and examines how these patterns are associated with creative solutions to problems. Our research suggests that certain communication behavior of groups, when appropriately organized, can be of help in enhancing creative production of outcomes. A qualitative study was conducted on communication patterns based on an analysis of text-based electronic conversation protocols. Specifically this research tried to overcome existing studies on electronic groups by focusing on interactive process of communication among participants. The major study conclusions are: (1) Satisfation of group decision-making may depend on the process or sequence of discussion among group members with Instant Messenger. That is, proper interactive responses and appropriate control of the discussion process are essential to obtain a high level of performance. (2) It is important to ]mike discuss rules based on meta-cognitive and interactive protocols in the early stage. Explicit rules relating to internal group processes as well as communication medium use are even more important to groups with Instant Messenger than face-to-face groups.

• Journal of Korean Academy of Nursing Administration
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• v.12 no.3
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• pp.365-372
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• 2006

Purpose: OSCE, Objective Structured Clinical Examination, is a good way to evaluate clinical skills of nursing students. To do this, we need modules, evaluators, persons to run the examination, as well as models and standardized patients if necessary. Author coached nursing students to develop modules and ran the examination by themselves. Method: 24 third-year and 4 first-year students volunteered; third-year students developed 5 modules, and organized and ran the examination. First-year students played patient role. 60 2nd-year students participated as examinees. Modules were duplicated to finish examination in a given time. The relationship between OSCE score, conventional clinical evaluation score and credit of students was compared. Effect of module duplication on score was tested. And responses of examinees were collected. Results: There was no correlation between OSCE and conventional clinical evaluation score (r=0.07), and credit (r=0.27), And there was no difference of OSCE score between duplicated modules $(53.77{\pm}7.61$ vs $55.33\pm7.74).$ Response of examinees to OSCE was favorable. Examinee did not expressed resistance for the evaluation by OSCE developed and ran by students. Conclusion: Nursing students successfully developed and ran OSCE, which was accepted favorably by examinees. Student-developed OSCE may play a role in evaluation of clinical performance.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.6
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• pp.1356-1363
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• 2005

In the gyrocompass system, the use of the fiber optic gyroscope(FOG) makes this traditional system considerably attractive because it has strong points in terms of weight, power, warming-up time, and cost. In this paper, a novel digital north-finding method based upon an FOG, which can be applied to the gyrocompass system, is proposed. The analytical model for the earth signal of the FOG is described, and the earth signals passed through lock-in amplifiers are modeled. Additionally, a north-finding algorithm using two lock-in amplifier outputs is developed, and the proposed method is organized by the developed algorithm. Simulation results are included to verify the performance of the proposed method.