• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.36 no.6
• /
• pp.594-597
• /
• 2023

We have proposed and demonstrated a fiber optic RH (relative humidity) sensor based on fiber Bragg grating covered with a polyimide film. As the polyimide film absolves the moisture in the air, its volume expands. As a result, the grating period of the FBG (fiber Bragg grating) covered with a polyimide film becomes wide and the Bragg wavelength is shifted. The sensor is implemented by fixing a 30 ㎛ thickness polyimide film on the surface of an optical fiber grating using an adhesive, and the characteristics of the device according to humidity are analyzed. The fabricated FBG RH sensor showed a high sensitivity of 0.0186 nm/RH% and a wide measurement range from 30% to 90%. The influence of environmental temperature on the characteristics of the RH sensor was also measured and analyzed. The feasibility of commercialization is presented.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.39 no.6
• /
• pp.531-536
• /
• 1994

Drainage duration before seeding and furrow depth desirable for establishment and growth in direct drill seeding of rice on puddled paddy soil were investigated. Furrow depths tested were 2, 4 and 6cm in combination with drainage duration 2, 4, and 6days. Dongjinbyeo was used and seeded on May 11, 1993. Seedling establishment were improved by longer drainage duration and by shallower furrow. Lodging occurred moderately at furrow depth of 2cm with 4 and 6days of surface drainage before seeding. This lodging might be attributable to the shallow burying of shoot below soil surface. Rice yield was highest at furrow depth of 4cm with 4days drainage before seeding. In considering seedling establishment and yield, desirable drainage duration before seeding and furrow depth might be 4days and 4cm, respectively. Cone(115g) penetration depth, dropped at 1m above soil surface, was 6 to 7cm on the date after 4days drainage before seeding.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.41 no.3
• /
• pp.295-301
• /
• 1996

This study was carried out to clarify the effect of sprout length, burried depth of seed and CaO$_2$ seed coating on emergence, seedling stand and early growth of rice in puddled-soil drill seeding at Junbuk in 1995. The cultivar tested was Dongjinbyeo(Japonica type). Although the longer sprouted seeds were caused the better seedling stand, 4mm sprout length of seeds appeared to be appropriate for good seedling stand and seeding uniformity, while 6mm sprouted seed resulted in ununiform seedling establishment. Rapid emergence and increased seedling stand were obtained by CaO$_2$ seed coating, which had effect more on soaked seed than on sprouted seed, but the seedling stand of sprouted seeds significantly reduced at deeper than 1cm seeding depth and also emergence rate of sprouted seeds significantly reduced at deeper than 2cm seeding depth.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.42 no.4
• /
• pp.483-488
• /
• 1997

This experiment was conducted to determine cutting time on the yield and nutritive value of brittle culm rice. Plant height and number of tiller were significantly different between variety and cutting time, and regrowth plant height and rate of regrowth tiller were tall and high at the early cutting. Early cutting increased crude protein, fat and NFE(Nitrogen free extract) content in the harvested foliage but crude fiber and ash content were decreased in the first cutting. Those of second cutting also showed reverse tendency. Fresh and dry matter yield were highest on heading date cutting, and those of KL501 were higher than those of Seomjinbyeo. TDN(Total digestible nutrients) content was higher with earlier cutting for initiated cutting, but that of second cutting was reversed. KL501 showed higher TDN content than Seomjinbyeo did at the any cutting time. TDN yield of heading date cutting was higher than that of the other cutting time.

• Maritime Security
• /
• v.6 no.1
• /
• pp.109-135
• /
• 2023

The North Korean military's maneuver toward Honam was the fastest maneuver the North Korean army had demonstrated during the Korean War, and it was a threatening attack that forced the Korean and Allied forces to fully adjust the defenses of the Nakdong River. However, when this study analyzed the North Korean military's maneuver toward Honam in terms of indirect approach strategy, there were a number of factors that inevitably led to its failure. In terms of implementing the indirect approach strategy, the North Korean military cited a number of failure factors, including the dispersion of combat forces, the inflexibility of changing the line of operation, the maneuvering of ground forces, and the lack of psychological distaction. However, the North Koreans were preparing for a final "surprise attack," in which the 7th Division, which was following the North Korean 6th Division, took another diversion and attempted to attack in the direction of Tongyeong. With this, the North Koreans intended to break through the Nakdong River defenses and head for Pusan. However, the North Korean attack was ultimately thwarted by the Korean Navy and Marine Corps' Tongyeong Amphibious Operation. With a swift maneuver using the sea as a maneuvering space, the Navy and Marine Corps occupied key points first, creating an advantageous situation and fending off an attack by the North Korean 7th Division. The Navy and Marine Corps' Tongyeong Amphibious Operation finally thwarted the North Korean military's maneuver toward Honam, thus maintaining the Nakdong River defenses.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.39 no.5
• /
• pp.495-501
• /
• 1994

This experiment was carried out to investigate the proper seeding methed for direct seeding culture of rice in puddled soil at ill-drained paddy field. Mangeumbyeo was seeded on May 11 with drill seeder attached to cultivater, dibbling seeder attached to transplanter and power dust blower. And to determine the proper flooding time after seeding, Mangeumbyeo was seeded on May 7 and June 1 with drill seeder. Emergence ratio wasn't significantly different between drill seeder seeding and dibbling seeder seeding but emergence was very low with power dust blower. Working hour for seeding was shortened in the order of power dust blower, drill seeder and dibbling seeder, and these seeding methods saved the working hour remarkably compared with machine transplanting of infant seedling by omitting the procedures of raising seedling and transplanting. Lodging occurred slightly in all seeding methods. However, yield wasn't significantly different between machine transplanting of infant seeding and direct seeding culture in puddled soil except power dust blower. When field was flooded on seeding date, the emergence period was shortened, emergence ratio was increased and weed occurrence was decreased. Yield was highest when flooding was done on seeding date as the number of panicle per m$^2$ and the number of spikelets per m$^2$ were higher than any other flooding time.

• KOMUNHWA
• /
• no.56
• /
• pp.29-58
• /
• 2000

A lot of dolmens without burial chamber have been brought to the light around Honam (southwestern provinces of Korea) area. Even though they are commonly classified as dolmens of surrounding stone type(圍石式), it seems necessary to put under the category of

• 지역과문화
• /
• v.6 no.1
• /
• pp.57-80
• /
• 2019

In this study, we will investigate Nujung culutre of Seobuk-jung in Hamra, which is representative Nujung in the modern period Iksan region, and examine how to use it as local contents. Hamra, where Seobyeog-jeong is located, was an economic center in the Joseon Dynasty. Under the historical and economic background, Seobyeong-jeong was erected by Lee, Chip-chon in 1926. The study of Seobyeong-jeong and Nujung culture erected by the Landloard family of Honam in modern times can be used as an important data for understanding the Nujung culture of modern Iksan Proviance.

• Honam Mathematical Journal
• /
• v.1 no.1
• /
• pp.61-75
• /
• 1979

In this explanation. we shall describle how the de Rham's cohomology on a n-dimensional $C^{**}$-manifold is constructed. The Čech's cohomology defined by only topological structure of $C^{**}$-manifold has a crack that it is dependent on the covering of a $C^{**}$-manifold. At the end of explanation we shall prove that the de Rham's cohomology is isomorphic to Čech's cohomology which is made by simply covering.

• Honam Mathematical Journal
• /
• v.1 no.1
• /
• pp.1-9
• /
• 1979

Positive Local Coordmate($(x^1,x^2,{\cdots}x^n)$)을 갖는 Oriented Manifold M을 생각한다. M이 Compact Carrier를 갖는 경우, M위의 n차(次) Differential Form ${\phi}^{(n)}$의 적분(積分)을 $${\int}{\phi}^{(n)}=\sum_{\alpha}{\int}_{-{\infty}}^{\infty}{\cdots}{\int}_{-{\infty}}^{\infty}f_{\alpha}{\phi}^{(n)}dx^1{\cdots}dx^n$$로 정의(定義)하며 (정의(定義) 7), M위의 p 차(次)의 Differential form $\beta^{(p)}$와 Differential simplex $S^{(p)}=(S^{(p)},\;{\pi},\;{\varepsilon})$에 대하여 $S^{(p)}$위의 $\beta^{(p)}$의 적분(積分)을 $${\int}_{^{(p)}S}{\beta}^{(p)}={\int}_{S^{(p)}}{\varepsilon}{\pi}^*{\beta}^{(p)}={\int}_{E^p}f{\cdot}{\varepsilon}{\cdot}{\pi}^*{\beta}^{(p)}$$로 정의(定義)한다 (정의(定義) 9). 단(但) $\bar{S}^{(p)}$는 $S^{(p)}=(p_0{\cdot}p_1{\cdots}p_p)$에 의(依)하여 Spanning 되는 $E^p$의 Subspace이고 f는 $\bar{S}^{(p)}$의 특성함수(特性函數)이다. 이때 (n-1)차(次)의 Differential Form ${\beta}^{(n-1)}$이 Compart인 Carrier를 가지면 ${\int}d{\beta}^{(n-1)}=0$이 됨을 고찰(考察)하며(정리(定理 8), (p-1)차(次) Differential Form ${\beta}^{(p-1)$과 p차(次) Differential Chain $C^{(p)}$에 관(關)하여 $${\int}_{C^{(p)}}d{\beta}^{(p-1)}={\int}_{{\partial}C^{(p)}}{\beta}^{(p-1)}$$이 성립(成立)함을 구명(究明)하려 한다(정리(定理) 10).