• Journal of KIISE:Computer Systems and Theory
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• v.32 no.7
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• pp.341-348
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• 2005

Detecting unaffected race conditions is important for debugging message-passing programs effectively, because such races can influence other races to occur or not. The previous technique used in detecting unaffected races detects a race by halting the execution of a process at the receive event of the race that errors first in the process. However this technique does not guarantee that all of the detected races are unaffected, because halting the execution of processes does disconnect some chains of affects-relations among those races. Tn this paper. we improved the second pass algorithm of the previous technique by producing information about affects-relations of the races that occur first in each Process. Then we effectively visualize affect-relations among the races detected in each process. This visualization is effective in detecting visually unaffected races by simplifying affects-relations among the races which occur first In each Process.

• Journal of the Korea Society of Computer and Information
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• v.19 no.4
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• pp.17-24
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• 2014

Detecting data races is important for debugging shared-memory programs with nested parallelism, because races result in unintended non-deterministic executions of the program. It is especially important to detect the first occurred data races for effective debugging, because the removal of such races may make other affected races disappear or appear. Previous dynamic detection tools for first race detecting can not guarantee that detected races are unaffected races. Also, the tools does not consider the nesting levels or need support of other techniques. This paper suggests a post-mortem tool which collects candidate accesses during program execution and then detects the first races to occur on the program after execution. This technique is efficient, because it guarantees that first races reported by analyzing a nesting level are the races that occur first at the level, and does not require more analyses to the higher nesting levels than the current level.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.9
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• pp.1582-1589
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• 2006

A lock mechanism is essential for synchronization on the multiprocessor systems. The conventional queuing lock has two bus traffics that are the initial and retry of the lock-read. %is paper proposes the new locking protocol, called WPV (Waiting Processor Variable) lock mechanism, which has only one lock-read bus traffic command. The WPV mechanism accesses the shared data in the initial lock-read phase that is held in the pipelined protocol until the shared data is transferred. The nv mechanism also uses the cache state lock mechanism to reduce the locking overhead and guarantees the FIFO lock operations in the multiple lock contentions. In this paper, we also derive the analytical model of WPV lock mechanism as well as conventional memory and cache queuing lock mechanisms. The simulation results on the WPV lock mechanism show that about 50% of access time is reduced comparing with the conventional queuing lock mechanism.

• Defense and Technology
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• no.3 s.265
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• pp.32-43
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• 2001

국방과학연구소는 정밀기술진흥대회에서 우수 첨단기술을 보유하고 있는 산업체 및 연구소들과의 치열한 기술경합을 통해 4번의 대회참가 중 3회에 걸쳐 금상을 수상받은 최초의 연구기관으로 기록을 남겼다. 군 무기체계를 연구개발하는 국방과학연구소가 정밀기술진흥대회 참가를 통해 대.내외적으로 공인된 관련기술들을 산업체에 개방 및 기술이전함으로써 국가산업 경쟁력 제고에 기여하였다. 지금은 세계 속의 경쟁력있는 연구소를 목표로 하고 있기 때문에 세계 수준의 첨단기술 및 기술 경쟁력을 확보하기 위해서는 대외적인 각종 정밀기술대회에 능동적으로 참가해야 할 핑요성이 증대되고 있다. 우수한 첨단기술을 보유한 산업체들가 기술경쟁을 통해 연구소가 보유하고 있는 분야별 국방관련 기술이 산업체보다 우수함을 검증받아야만 산업체에서 필요로 하는 관련 기술을 산업체들에게 효과적으로 이전시켜 줄 수 있기 때문이다. 따라서 연구소의 주체인 연구원들이 대외의 각종 정밀기술진흥대회에 자발적인 참가를 통해 자체 보유기술에 대한 대.내외 검증과 이로 인한 창의적인 기술개발을 보다 활성화시킬 수 있도록 연구소 차원의 지원과 관련제도의 뒷받침이 절실히 요구된다.

• Journal of the Korean Geographical Society
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• v.48 no.6
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• pp.944-966
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• 2013

This study attempts to highlight the cultural importance of urban public space by analyzing the changes Tap-Gol Park from late 1990's to early 2000's, a park located in the heart of Seoul, underwent in its meanings and uses. Public space, a product of modern urban planning, is characterized by its openness and accessibility and represents the vitality of modern city, serving as a meeting place for citizens with different social backgrounds at such occasions as gatherings and festivals. While the government or a few dominant groups try to control the public and their behavior in public space by giving a specific meaning to it and specifying its use, people constantly set their foot in it and view the space as a place differently for each individual's personal or social reasons. It is therefore not very surprising that the meaning of public space has never been successfully defined. Following the traces of attempts to define the meaning of public space and considering how public space can be efficiently used will shed light on what types of groups, especially ages and classes participated in the contest for the use of public space and expressed their own cultures in urban society through various negotiations.

• Journal of KIISE:Computer Systems and Theory
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• v.28 no.9
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• pp.424-433
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• 2001

The cyclic debugging approach often fails for message passing parallel programs because they non-deterministic characteristics due to message race conditions. This paper identifies the MPI events that affect non-deterministic executions, and then converts the concurrent execution to the sequential one that is controlled in order to make it equivalent to a reference execution by keeping their orders of events in two executions identical. This paper also presents an efficient algorithm for the causal distributed breakpoint which is initiated by any sequential breakpoint in one process, and restores each process to the earliest state that reflects all events that happened causally before the sequential breakpoint. So a cyclic debugging approach can be used in debugging MPI parallel programs as like as in debugging sequential programming environments.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.1
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• pp.43-48
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• 1986

The experiment was conducted to know the varietal difference in changing aspect of daily filling sink during of rice using three cultivars; ‘Suweon 295’ (japonica), ‘Suwoen 264’ and ‘IR 1317-70-1’ (semi-dwarf indica) cultivated in the field and green house of the Crop Experiment Station in 1983. There was not significant varietal difference in flowering habit and duration of flowering period each panicle. Semi-dwarf indica cultivars showed shorter days to physiological maturity of rice kernel than the japonica one. The former also displayed earlier decrease in water content of rice grain during ripening than the latter. Japonica variety revealed larger difference in ripening advancement between vigorous florets and inferior one than semi-dwarf indica varieties. The semi-dwarf indica rice cultivars expressed significantly shrewder parabola of daily filling of sink per panicle during ripening than the japonica one. The time showing maximum capacity of daily filling of sink per panicle during ripening was 10-12 days after anthesis. The filling capacity of daily sink filling per panicle for 'IR 1317-70-1', 'Suweon 264' and 'Suweon 265' at this time were about 240 mg, 165 mg and 145 mg, respectively. Pattern of sink filling per panicle during ripening was slightly changed by the cultural environment. ‘Suweon 295’ showed slightly sharper parabola and 2-3 days earlier time showing maximum capcity of daily sink demand per panicle during ripening in the field than those in the green house.

• Korean Journal of Weed Science
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• v.16 no.2
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• pp.81-87
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• 1996

Seeds of rice, cv. Ilpoom, and barnyardgrasses(Echinochloa crus-galli, vars. oryzicola, crux-galli, and praticola) were sown for a characterization of their responses to temperature during emergence under a dry direct-seeded condition. A laboratory-made aluminum block apparatus for emergence-temperature control conferred a linear continuous temperature gradient from 10 to $30^{\circ}C$ to the seeds from cooling to heating ends of the apparatus. The lowest temperature for emergence was $12.3^{\circ}C$ for rice cv. Ilpoom, and $11.0^{\circ}C$ for the three varieties of Echinochloa spp.. Percent emergence of rice increased sharply with an increase in temperature by ca. $20^{\circ}C$, then leveled-off, while those of barnyardgrasses increased almost linearly with temperatures up to $30^{\circ}C$. In rice the time required for emergence after seeding was shortened exponentially with increased temperature while those for barnyardgrasses were shortened almost linearly from 11 to $30^{\circ}C$. The temperature-response characteristic of rice in emergence-speed was almost the same among those for the 1st emergence, emergence by 25, 50, 75%, or average emergence time. At $13^{\circ}C$, $346.7^{\circ}C$ days of accummulated temperature(26.67 days) were required for the 1st emergence in rice while 131.7, 136.0, and $138.7^{\circ}C$ days(10.13, 10.46, and 10.67 days) were required for the 1st emergence in E. spp., vars. crus-galli, praticola, and oryzicola, respectively. Greater cold tolerance and increasingly faster emergence of barnyardgrasses than rice below $20^{\circ}C$ seem to render the barnyardgrasses as much more competitive than rice at lower temperatures.

• Korean Journal of Weed Science
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• v.16 no.2
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• pp.88-99
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• 1996

In recent years dry direct-seeding of rice has been encouraged by the government and increasingly practiced by farmers in Korea. This has been bringing up an increased occurrence of weedy rites. Some farmers in the southern region dare to sow the rice before winter after harvest, while most farmers wish to sow as early as possible in the spring to secure the growing period, and to disperse the intensive labor in early May. The purpose of this study was to determine the feasibility of moving the sowing of rice to an earlier date under dry direct-seeding, and to elucidate the nature of emergence of an old strain of rice, weedy rites, and barnyardgrasses tinder this farming practice and their adaptive competence over present cultivate. The presently recommended rice cultivar, Dongjinbyo and an old rice strain, Dadajo which prevailed in early 1900s, almost could not emerge from soil deeper than 6cm and could emerge to only 5.3% at best from 1cm deep loamy soil field when the seeds were sown on Nov. 28. However, two strains of weedy rites being weedy for over 200 years emerged by 17.0 to 63.0% from the loamy and sandy clay loam field 1 to 6cm deep. Emergence of the weedy rites was greater in the loamy soil and at a shallow depth, and negligible from the soil depth of 9cm. Barnyardgrasses sown on Nov. 28 emerged by 13.4 to 51 % from the 1 to 3cm deep loamy soil, and 8.6 to 46.7% from the 1cm deep sandy clay loam. Echinochloa crus-galli var. crus-galli emerged more than var. praticola, and var. oryzicola least. Most of the non-emerged barnyardgrasses seem to have entered secondary dormancy. Seeding rice a month earlier than the season lowered the emergence of Dongjinbyo by ca. 10, 18, and 26%, respectively at 1, 3, and 6cm soil depths, indicating that moving the seeding date a month earlier is impractical. The old strain, Dadajo sown in the soil at a depth of 6cm responded similarly. However, the strain has shown a significantly higher ability in emergence from 9cm deep soil. Weedy rices sown a month earlier A month earlier sown weedy rices have shown very similar emergence rates at various soil depths to those sown on May 1. Barnyardgrasses have also shown similar emergence rates when sown between April 3 and May 1. Like barnyardgrasses, the old strain and weedy rices apparantly posessed a greater adaptability to emerge under lower temperatures, and from deeper soil ; Dongjinbyo${\leq}$ Echinochloa species in that order. However, emergence- speed under lower temperature(sown on April 3) was faster in the order of weedy rice