• Korean journal of applied entomology
• /
• v.40 no.1
• /
• pp.1-4
• /
• 2001

The American species Melanolophia imitata (Walker) is recorded for the fist time from Korea. The species attacks various coniferous trees in Canada and, in prospect, it can stay a serious pest of forestry in East Asia.

• Journal of Institute of Control, Robotics and Systems
• /
• v.11 no.11
• /
• pp.936-942
• /
• 2005

Recently the exoskeletal power assistive equipment which is a kind of wearable robot has been widely developed to help the human body motion. For the elderly people and patients, however, some limits exist due to the weight and volume of the equipments. As a feasible solution, a tendon-driven exoskeletal power assistive device fur the lower body, and caster walker are proposed in this research. Since the caster walker carries the heavy items, the weight and volume of the wearable exoskeleton are minimized. The key control is used to generate the joint torque required to assist motions such as sitting, standing and walking. Experiments were performed for several motions and the EMG sensors were used to measure the magnitude of assistance. When the motion of sitting down and standing up was compared with and without wearing the proposed device, the $25\%$ assistance was acquired.

• Journal of Korean Neurosurgical Society
• /
• v.56 no.1
• /
• pp.61-65
• /
• 2014

Neurocutaneous melanosis (NCM) is a rare congenital syndrome consisting of benign or malignant melanotic tumors of the central nervous system with large or numerous cutaneous melanocytic nevi. The Dandy-Walker complex (DWC) is characterized by an enlarged posterior fossa with high insertion of the tentorium, hypoplasia or aplasia of the cerebellar vermis, and cystic dilatation of the fourth ventricle. These each two conditions are rare, but NCM associated with DWC is even more rare. Most patients of NCM with DWC present neurological symptoms early in life such as intracranial hemorrhage, hydrocephalus, and malignant transformation of the melanocytes. We report a 14-year-old male patient who was finally diagnosed as NCM in association with DWC with extensive intracerebral and spinal cord involvement.

• Korean Journal of Soil Science and Fertilizer
• /
• v.24 no.4
• /
• pp.293-301
• /
• 1991

Spores of the family Clomaceae, Acaulosporaceae. and Gigasporaceae in the ord er Clomales. isolated from greenhouse soils grown horticultural crop in the southern region of Korea, included those of the following species : Acaulospora biretculata Rothwell & Trappe, A. appendiculata Spain, Sievering & Schenck, A. foveata Trappe & Janos, A. denticulata Sievering and Toro. A. elegans Trappe & Gerd., A. rehmii Sieverding & Toro in Acaulospora species, Gigaspora gigantea (Nicol. & Gerd.) Cerd. & Trappe, G. decipiens Hall & Abbott in Gigaspora species, Glomus ambisporum Schenck & Smith, G. hoi Berch & Trappe, G. caledoniwn (Nicol. & Gerd.) Trappe & Gerd. in Glomus species, Scutellispora aurigloba (Hall) Walker & Sanders, S. calospora (Nicol. & Gerd.) Walker & Sanders, S. coralloidea (Trappe, Gerd. & Ho) Walker & Sanders in Scutellispora species. Sporocarps of Sclerocystis pachycaulis Wu & Chen were also found.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2012.05a
• /
• pp.1147-1148
• /
• 2012

• The Journal of the Acoustical Society of Korea
• /
• v.15 no.2E
• /
• pp.4-7
• /
• 1996

In this paper, we propose a formula to compute the exact autocorrelations of the autoregressive (AR) process. For an arbitrary value of N, we first review the Yule-Walker equation and some basic properties of the AR model. We then modify the Yule-Walker equation to construct a new system of N+1 linear equations that can be used to solve for the N+1 autocorrelation coefficients for lags 0, 1, …, N, provided that the AR parameters of order N and the power of the white noise of the AR process are given.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2013.05a
• /
• pp.1427-1428
• /
• 2013

• Communications of the Korean Mathematical Society
• /
• v.29 no.2
• /
• pp.295-310
• /
• 2014

This paper provides a study of lightlike submanifolds of a generalized Robertson-Walker (GRW) space-time. In particular, we investigate lightlike submanifolds with curvature invariance, parallel second fundamental forms, totally umbilical second fundamental forms, null sectional curvatures and null Ricci curvatures, respectively.

• Bulletin of the Korean Mathematical Society
• /
• v.49 no.4
• /
• pp.863-874
• /
• 2012

We provide a study of lightlike hypersurfaces of a generalized Robertson-Walker (GRW) space-time. In particular, we investigate lightlike hypersurfaces with curvature invariance, parallel second fundamental forms, totally umbilical second fundamental forms, null sectional curvatures and null Ricci curvatures, respectively.

• Korean Journal of Mathematics
• /
• v.28 no.1
• /
• pp.75-87
• /
• 2020

Category F Rel of fuzzy sets and relations does not form a topos. J. Harding, C. Walker and E. Walker [3] showed that FRel has a tensor product and V. Durov [1] introduced basic definitions related to the notion of vectoid endowed with a tensor product. In this paper, we show that FRel forms a quasi topos. Also we show that there are quasi power objects in FRel. And by the use of the concepts of FRel and quasi topos, we get the logic operators of FRel. Moreover, we show that FRel forms a vectoid.