• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.3
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• pp.163-170
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• 2016

Heading time is important element for yield and quality in crops. Among day length and temperature which influence on heading, temperature effect has not been investigated well. To investigate temperature effect on heading, heading date and plant growth characters were checked under the low and high temperature conditions in short day length. Analyzing heading date of six Korean varieties under the high and low temperature condition, heading date of varieties were delayed under low temperature. In the low temperature condition, dry weight and area of leaf were reduced. Varieties showing more delay of heading under low temperature also showed more reduction in leaf area. After selecting three varieties showing significant difference in leaf growth and heading date under different temperature conditions, nutrient contents of plant were analyzed. Nitrogen content was reduced in leaf and shoot under the low temperature condition. OsNRT2.3, nitrate transporter, was significantly down regulated in varieties showing more heading delay. Available phosphate content was decreased in leaf, but increased in shoot due to reduction of phosphate mobility. OsPT1, phosphate transporter regulating phosphate uptake, was more down regulated in varieties showing more heading delay. OsPT6, phosphate transporter regulating phosphate transport in plant, was also significantly down regulated in those varieties. With these data, we expected that active nitrogen and available phosphate uptake and transport in plant would increase leaf growth then might reduce heading delay under the low temperature condition.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.4
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• pp.221-226
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• 2000

This experiment was designed to assess changes in yield difference between waxy (IWR) and non-waxy (INWR) near isogenic rice by evaluating the translocation and accumulation of assimilates in different parts of the rice plants after heading stage under different fertilizer application. Nitrogen content of culm in both IWR and INWR decreased rapidly from 35 days before heading to flowering time and after then it was maintained constantly, while the nitrogen content of leaf blade was continually reduced. Sugar content of leaf blade in IWR decreased steadly by 10 days after heading, but that in INWR increased 20 days after heading. There was no difference in starch content of culum between IWR and INWR from 35days before heading to heading, but that of culm of IWR increased again after heading. Dry weight of IWR plant was less reduced during ripening as compared with INWR. The dry weight of culm was not significantly different between two isogenic lines.

• Journal of Ocean Engineering and Technology
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• v.34 no.2
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• pp.77-88
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• 2020

In this study, heading characteristics and heading control performances were evaluated to achieve the wave shield effect. The wave shield effect originating from heading control reduces the relative motions of moored vessels in a floating liquefied natural gas bunkering terminal (FLBT). Therefore, loading and off-loading performances are improved through reduced relative motion. For the objective of this study and efficiency of the analysis, a simplified model was used that assuming no relative motion of the moored vessels in the FLBT. The simplified model involved modeling the environmental loads and inertia of several floating bodies, including FLBT, into the environmental loads and inertia of a single vessel. The simplified model was validated through comparisons with model tests. With the simplified model, heading characteristics and heading control simulations were performed using low-frequency planar motion equations. The heading characteristics and heading control performances of FLBT were analyzed through the results of simulations under the expected environmental conditions. The capacity of the tunnel thrust for the heading control performance was confirmed to be adequate for improvement of the loading and off-loading performances using the wave shielding effects under the operation conditions.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.3
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• pp.213-224
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• 2019

There is an increasing frequency in the occurrence of abnormal weather phenomena such as sharp increases and decreases in temperature. Under these weather conditions, the heading time of rice changes unexpectedly, which poses problems in agriculture. Therefore, we investigated the effect of temperature on the heading response at different growth stages in rice. During the period from transplanting to heading, the plants were subjected to different temperature treatments, each for a 9-day period, to observe the heading response. For the heading date analysis, "heading date" was defined as the number of days from transplanting to the appearance of the first spikelet. We found that the influence of temperature increased in the order of rooting stage, followed by meiosis, early tillering, spikelet differentiation, and panicle initiation stage in all ecological types and cultivars. In particular, unlike the results reported previously, the effect of temperature on heading during the photo-sensitive period was very small. Meanwhile, the influence of temperature on vegetative growth response at different growth stages was not consistent with heading response. These results can be used as basic data for predicting the variation in heading date owing to temperature variation at each growth stage. In addition, we propose that the concept of day length should be included in determining the influence of temperature on the photo-sensitive period.

• Journal of Institute of Control, Robotics and Systems
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• v.8 no.6
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• pp.524-532
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• 2002

This paper presents a new in-flight alignment method for an SDINS under large initial heading error. To handle large heading error, a new attitude error model is introduced. The attitude errors are divided into heading error and leveling errors using a newly defined horizontal frame. Some navigation error dynamic models are derived from the attitude error model for indirect feedback filtering of the in-flight alignment system. A Kalman filter with Position measurement is designed to estimate navigation errors as the indirect feedback filter Simulation results show that the proposed in-flight alignment method reduces the heading error very quickly from more than 40deg to about 5deg so as to apply a refined navigation filter. The total alignment process including leveling mode and navigation mode in addition to the proposed one allows large initial values not only in heading error but also in leveling errors.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.6
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• pp.468-472
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• 2001

In order to know the relationship between the accumulated temperature distribution and barley growth characteristics, average, early and late heading years were analyzed. Among 24 year's crop situation test 1976, 1979, 1989, 1990, 1998 were sorted to early heading years and 1977, 1980, 1984, 1996 to late heading years. About $650^{\circ}C$ of accumulated temperature from October to December was enough to get average year's heading date in barley. While 62$0^{\circ}C$ of accumulated temperature were not enough for average heading, 67$0^{\circ}C$ of accumulated temperature accelerated barley heading. 78$0^{\circ}C$ of accumulated temperature from October to February, were enough to get average year's heading date in barley. while $650^{\circ}C$ of accumulated temperature were not enough to, 78$0^{\circ}C$ of accumulated temperature accelerated barley heading. Temperature pattern types in early heading years were distinguished by three types : high temperature type before winter(I), high temperature type in winter-regrowth stage(II), high temperature type in tillering stage(III). On the other hands, temperature pattern types in late heading years were divided to two types : low temperature type in winter-regrowth stage(I), low temperature type in tillering stage(II). Barley heading was mainly influenced by temperature before winter and winter-regrowth stage. Yields of early heading years were higher than that of late heading years and yield was heavily influenced by the number of spikes per square meter.

• The Journal of Korea Robotics Society
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• v.6 no.4
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• pp.334-343
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• 2011

This paper presents a new approach for mobile robot heading detection using MEMS Gyro north finding method in the indoor environment. Based on this, the robot heading angle measurement scheme is proposed; improved north finding theory and algorithm are also explained. Several approaches are applied to confirm system's precision and effectiveness. In order to find out the heading angle, a single axis MEMS gyroscope to sense the angle between the robot heading direction and the north is used. To reach enough estimation accuracy and reduce detection time, the least square method (LSM) for the signal fitting and parameter estimation is applied. Through a turn-table, we setup a carouseling system to decrease the substantial bias effect on gyroscope's heading angle. For the evaluation of the proposed method, this system is implemented to the Pioneer robot platform. The performance and heading error are analyzed after the test. From the simulation and experimental results, system's accuracy, usefulness and adaptability are shown.

• Journal of Korean Library and Information Science Society
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• v.32 no.4
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• pp.257-282
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• 2001

The purpose of this study is to suggest a rational guidelines of authority record for personal name heading control. It analyzes the Statement of Principles of ICCP, the headings of Korean Cataloging Rules and personal name heading of KORMARC on Disc. It also investigates the problems and suggests the possible improvements for headings of personal name. The rules for heading control retains the frame from headings of cataloging rules. The guidelines for heading control of personal name will be integrated in the rules for headings. To efficient retrieval, It suggests distinction of different persons of the same name and subject List.

• Proceedings of the Acoustical Society of Korea Conference
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• 1984.12a
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• pp.100-106
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• 1984

Traditional methods for estimating the location of underwater target, i.e. the triangulation method and the wavefront curvature method, have been utilized. The location of a target is defined by the range and the bearing, which estimates can be obtained by evaluating the time delay between neighboring sensors. Many components of error occur in estimating the target range, among which the error due to the fluctuation of heading angle is outstanding. In this paper, the wavefront curvature method was used. We considered the error due to the heading fluctuation as the $\beta$-density process, from which we analized the range estimates with $\beta$-density function exist in some finite limits, and its mean value and variation are depicted as a function of true range and heading fluctuation. Given heading angles and sensor separation, maximum estimated heading errors are presented as a function of true range.

• Journal of the Korean Institute of Navigation
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• v.21 no.2
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• pp.59-67
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• 1997

This paper describe the method and the result of making a fiber optic gyrocompass measuring the heading angles of a ship with a fiber optic sensor. As the method seeking for the heading angles, it is possible to get the heading angles by measuring the output signals from a stationary fiber optic sensor in at least three directions such as a heading direction and other two directions having phase difference ${\phi}1$ and ${\phi}2$ to the heading. We made the static fiber optic gyrocompass by a high performance fiber optic sensor having scale factor of 210mV/deg/s and resolution of 0.5deg/hr using this principle. The accuracy of this system was $0.29^{\circ}$ from 20 numbers of data measuring the arbitrary heading angle.