• Journal of Plant Biotechnology
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• v.7 no.1
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• pp.1-15
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• 2005

Salinity is one of the major limiting factors for agricultural productivity. In plants, accumulation of osmolytes plays a pivotal role in abiotic stress tolerance. Likewise, exclusion or compartmentation of $Na^+$ ions into vacuoles provides an efficient mechanism to avert deleterious effects of $Na^+$ in the cytosol. Both vacuolar and plasma membrane sodium transporters and $H^+-ATPases$ can provide the necessary ion homeostasis. A variety of crop plants were engineered with respect to the synthesis of osmoprotectants and ion-compartmentation, but there are other cellular pathways involved in the salinity responses that are still not completely explored. Genomics approaches are increasingly used to identify genes and pathway changes involved in salt-tolerance. The new knowledge may be used via guided genetic engineering of multiple genes to create crop plants with significantly increased productivity in saline soils. This review surveys how plants deal with high salt conditions and how salt tolerance can be improved by transgenic approaches.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.2
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• pp.228-236
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• 2004

Two varieties of alfalfa (Medicago sativa L cv. Pioneer and Beaver) and timothy (Phleum pratense L cv. Climax and Joliette), grown at different locations in Saskatchewan (Canada), were cut at three stages [1=one week before commercial cut (early bud for alfalfa; joint for timothy); 2=at commercial cut (late bud for alfalfa; pre-bloom head for timothy); 3=one week after commercial cut (early bloom for alfalfa; full head for timothy)]. The energy values of forages were determined using three approaches, including chemical (NRC 2001 formula) and biological approaches (standard in vitro and in situ assay). The objectives of this study were to determine the effects of forage variety and stage of maturity on energy values under the climate conditions of western Canada, and to investigate relationship between chemical (NRC 2001 formula) approach and biological approaches (in vitro and in situ assay) on prediction of energy values. The results showed that, in general, forage species (alfalfa vs. timothy) and cutting stage had profound impacts, but the varieties within each species (Pioneer vs. Beaver in alfalfa; Climax vs. Joliette in timothy) had minimal effects on energy values. As forage maturity increased, the energy contents behaved in a quadratic fashion, increasing at stage 2 and then significantly decreasing at stage 3. However, the prediction methods-chemical approach (NRC 2001 formula) and biological approaches (in vitro and in situ assay) had great influences on energy values. The highest predicted energy values were found by using the in situ approach, the lowest prediction value by using the NRC 2001 formula, and the intermediate values by the in vitro approach. The in situ results may be most accurate because it is closest to simulate animal condition. The energy values measured by biological approaches are not predictable by the chemical approach in this study, indicating that a refinement is needed in accurately predicting energy values.

• Journal of the Korean Institute of Navigation
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• v.17 no.3
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• pp.69-76
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• 1993

In harbour the practical shiphandlers should have a expert knowledge of systematically reducing head-way and keeping ship's positions to the final position with confidence and under control. But now in the practical approaches we do not have any special maneuvers of controlling the ship effi-ciently regarding the headway and approaches except some existing reduction of speeds according to the Weight-to-Power Ratio, use of astern power and Rudder Cycling. Consequently this study put Woo's Super Rudder Controlling originally developed by Captain Woo, Ph. D. to practical use as a special maneuvers in the port approaches. The conclusions of this paper are drawn as follows : 1) Optimum standard and desirable controls in combination of three engine speeds with three yaw ang-les were proposed for the practical shiphandlers, 2) According to simulation of the pilotships the Super advances are 10.5 ship lengths for Full full full maneuvers, and 7.9 ship lengths for Full half maneuvers approximately, 3) Approach maneuvers to anchorages by trying Woo's Super Rudder Controlling saved about 30% of total standby time in comparison with the existing Weight-to-Power Ratio maneuvers in the Pusan and Kwang Yang ports.

• Research in Mathematical Education
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• v.16 no.3
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• pp.177-194
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• 2012

What strategies are used to help students understand quadratic functions in mathematics classroom? In specific, how does Chinese teacher highlight a connection between algebraic representation and graphic representation? From October to November 2009, an experienced teacher classroom was observed. It was found that when students started learning a new type of quadratic function in lessons, the teacher used two different teaching strategies for their learning: (1) Eliciting students to plot the graphs of quadratic functions with pointwise approaches, and then construct the function image in their minds with global approaches; and (2) Presenting a specific mathematical problem, or introducing conception to elicit students to conjecture, and then encouraging them to verify it with appoint approaches.

• Journal of Applied Reliability
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• v.15 no.1
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• pp.1-5
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• 2015

This note suggests three approaches to improve reliability in developing weapon systems. The high complexity of the weapon systems make it hard to analyze and predict of those reliability. Current situations of the reliability have been reviewed in terms of logistics support analysis (LSA), warranty policy, maintenance and development. Three suggestions are notified to improve the reliability considering the complexity of the weapon systems.

• Journal of Korea Technology Innovation Society
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• v.20 no.4
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• pp.1122-1158
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• 2017

Government-funded research institutes in the field of science and technology of Korea have contributed to the growth of the national economy and industrial development since the 1960s. However, those institutes recently have faced with criticism over the R&D performance on investment. Accordingly, we suggest two analytical approaches that estimate the economic benefit of the R&D performance of those institutes, (1) 'bottom-up' approach that aggregates the economic benefits of individual performances, e.g., technology transfer, technology support for small and medium enterprises, and the supply of researcher manpower and (2) 'top-down' one that estimates the contribution of those institutes on the economic growth of the industries that the R&D performance of those institutes is mainly utilized. In addition, by applying two approaches, we computed the economic benefit of the performance of the K institute in the 1996-2014 periods at 12.3 trillion won and 29.5 trillion won, respectively. Lastly, we suggest the feasibility of two approaches from the perspective of complementarity. Our study provides analytical approaches that estimate the economic benefit of the R&D performance from government funded research institutes in Korea. Lastly, our study contributes to the understanding of public on science and technology as well as the enhancement of legitimacy on those institutes among the public.

• Wind and Structures
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• v.34 no.1
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• pp.1-14
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• 2022

In this work the flow through a hollow porous 5:1 rectangular cylinder made of perforated plates is numerically investigated by means of 2D URANS based simulations. Two approaches are adopted to account for the porous surfaces: in the first one the pores are explicitly modeled, so providing a detailed representation of the flow. In the second one, the porous surfaces are modeled by means of pressure jumps, which allow to take into account the presence of pores without reproducing the flow details. Results obtained by using the two aforementioned techniques are compared aiming at evaluating differences and similarities, as well as identifying the main flow features which might cause discrepancies. Results show that, even in the case of pores remarkably smaller than the immersed body, their arrangement can lead to local mechanisms able to affect the global flow arrangement, so limiting the accuracy of pressure jumps based simulations. Despite that, time-averaged fields often show a reasonable agreement between the two approaches.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.9 no.6
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• pp.519-525
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• 2016

This paper addresses the framework of object-oriented image coding, describing a new algorithm, based on monodimensional Legendre polynomials, for texture approximation. Through the use of 1D orthogonal basis functions, the computational complexity which usually makes prohibitive most of 2D region-oriented approaches is significantly reduced, while only a slight increment of distortion is introduced. In the aim of preserving the bidimensional intersample correlation of the texture information as much as possible, suitable pseudo-bidimensional basis functions have been used, yielding significant improvements with respect to the straightforward 1D approach. The algorithm has been experimented for coding still images as well as motion compensated sequences, showing interesting possibilities of application for very low bitrate video coding.

• Journal of Power Electronics
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• v.10 no.1
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• pp.1-8
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• 2010

A new scheme for sliding-mode control (SMC) of DC-DC converters with a constant switching frequency is proposed. The scheme is based on the averaging model and the output signal of the controller is $d^+$ or $d^-$ instead of the on or off signal of a direct sliding-mode (SM) controller or the continuous signal d = $u_{eq}$ of an indirect SM controller. Two approaches using the new scheme are also proposed and the design procedures for a buck converter are given in detail. The first approach called constant $d^+$ and $d^-$ SMC is simple, cost effective and dynamically fast. In order to improve the dynamic characteristics of the reaching phase and to alleviate chattering, the second approach called reaching law SMC is also presented. Analyses and simulation results demonstrate the feasibility of the proposed scheme.

• Journal of the Korean Society of Clothing and Textiles
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• v.42 no.1
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• pp.195-209
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• 2018

This study reviewed emerging trends in 3D technology adopted in apparel design research and product development for rapid prototyping and effective evaluation of product performance. Based on a literature review, the authors discussed technical advantages, practical merits and limitations, applications, and on-going developmental efforts of the following methodologies focusing on 3D body scanning and 3D motion capture, and 3D virtual fit simulation technologies. Such data-driven technical approaches observed in recent apparel design research and industry practice are expected to increasingly be adopted in the field to improve consumers' satisfaction with functionality, aesthetics, and comfort of a wide range of apparel products that include daily wear, sport apparel and protective clothing.