• Journal of the Korea Institute of Military Science and Technology
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• v.25 no.1
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• pp.1-8
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• 2022

Electronic equipment mounted on military vehicles is exposed to external shocks and vibrations. This causes problems in tactical operation and also causes cost loss in equipment maintenance. Therefore, to optimize the test standards for military vehicles with vibration, dynamic characteristics should be analyzed and standardized through actual driving tests. In this paper, the internal structure of 2.5tons military vehicle is designed in the form of a drawer and lathe, and the dynamic characteristics are identified by experiment, and the design is proposed.

• IEMEK Journal of Embedded Systems and Applications
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• v.10 no.6
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• pp.345-352
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• 2015

Recently, by developing many training systems in battle field, the demand for interconnecting and internetworking between Live, Virtual, Constructive training systems has been increased to support efficient data distribution and system control. But, there are lots of problems for them to interwork, because the existing researches only support L-L, V-V, C-C Interoperability. Therefore, we propose L-V-C gateway to provide interoperable simulation environment based on HLA and DDS between them. First, we illustrate FOM Management that parses RPR-FOM XML file to acquire Data information to be shared between them, and generates common data structure and source code used for L-V-C Gateway. L-V-C Gateway created from FOM Management supports Data Conversion and Quality of Service between HLA and DDS. HLA Federate and DDS Domainparticipant in L-V-C Gateway play a role of logical communication channel and relay data from HLA Federation to DDS Domain and vice versa.

• Bulletin of the Korean Chemical Society
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• v.30 no.10
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• pp.2341-2344
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• 2009

Metallacyclodimers, [Ag(OTf)($L1)]_2$ and [Ag($L2)]_2(OTf)_2$ (L1 = 1,3-dibromo-2,2-bis[(isonicotinoyloxy)methyl] propane; L2 = 2,5-dimethyl-2,5-bis(isonicotinoyloxy)hexane) were constructed and characterized. The crystal structure of [Ag(OTf)($L1)]_2$ reveals a 32-membered cyclodimer, whereas that of [Ag($L2)]_2(OTf)_2$ shows a linked 34-membered cyclodimer chain via intercyclic argentophilic (Ag…Ag) interactions. [Ag(OTf)($(L1)]_2$ affords “intramolecular $\pi-\pi$ interaction cyclodimer” whereas [Ag($L2)]_2(OTf)_2$ produces a racemic mixture of “twisted cyclodimer”. Ring-conformation of the cyclodimers was affected via the competition of electrostatic interaction and argentophilic interaction.

• Journal of Information Processing Systems
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• v.10 no.1
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• pp.69-80
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• 2014

The free distance of (n, k, l) convolutional codes has some connection with the memory length, which depends on not only l but also on k. To efficiently obtain a large memory length, we have constructed a new class of (2k, k, l) convolutional codes by (2k, k) block codes and (2, 1, l) convolutional codes, and its encoder and generation function are also given in this paper. With the help of some matrix modules, we designed a single structure Viterbi decoder with a parallel capability, obtained a unified and efficient decoding model for (2k, k, l) convolutional codes, and then give a description of the decoding process in detail. By observing the survivor path memory in a matrix viewer, and testing the role of the max module, we implemented a simulation with (2k, k, l) convolutional codes. The results show that many of them are better than conventional (2, 1, l) convolutional codes.

• Phonetics and Speech Sciences
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• v.7 no.4
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• pp.139-145
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• 2015

The present study investigates the effects of syllable structure and prosodic prominence on the patterns of tonal alignment and scaling of the phrase-initial rise in Seoul Korean. Two syllable structures (Onset (/#CVC.../ as in minsa) vs. No-onset (/#VC.../ as in insa)) and two prominence conditions (Focus vs. Neutral) were considered. Results showed that the alignment of the L and the H tones in the phrase-initial rise was affected by syllable structure but not by prominence. The time of L was before the vowel onset of the first syllable in the Onset condition (i.e., within the onset consonant) and it was after the vowel onset in the No-onset condition. The difference was attributable to the fact that the initial L was anchored at a fixed distance from the phrase boundary, which was about 30ms after the onset of the syllable in both cases. The time of H was also consistently observed about 20ms after the second vowel onset (i.e., /a/ in minsa/insa). Moreover, the rise time (the duration from the L to the H tones) was longer as the local syllable duration became longer due to different syllable structure and prominence conditions. Taken together, the results provide a support for the segmental anchoring hypothesis, which claims that both the beginning and the end of F0 movement are consistently aligned with segmental 'anchor' points with relatively high stability (Ladd et al., 1999). Results also showed that the scaling of the early rise was slightly influenced by syllable structure but not by prominence. The differences between the results of the current study and a previous study (Cho, 2011) are further discussed.

• Journal of the Korean Magnetics Society
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• v.21 no.2
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• pp.43-47
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• 2011

It is known that the Fe-Al transition metal compounds have a lot of disagreement about structural stability and magnetism. In this study, the correlation between magnetism and atomic structure of ordered $B_2$, $L1_2$, and $D0_3$ structured Fe-Al compounds has been investigated using the all-electron full-potential linearized augmented plane wave (FLAPW) method based on the generalized gradient approximation (GGA). We found that considered all the structures were calculated to be stabilized in a ferromagnetic state. The calculated spin magnetic moments of the Fe atoms for B2 and $L1_2$ structures were 0.771 and 2.373 ${\mu}_B$, respectively, and that of Fe(I) and Fe(II) in $D0_3$ structure calculated to be 2.409 ${\mu}_B$, 1.911 ${\mu}_B$, respectively. In order to investigate structural stability between $L1_2$ and $D0_3$ structures, we performed the formation enthalpy calculations. As a result, the $D0_3$ structure is found to be more favorable than $L1_2 one by energy difference 16 meV/atom, which is well consistent with the experimental observation. We understood about structural stability and magnetism for Fe-Al compounds in terms of analysis of their atomic and electronic structures.

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2299-2303
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• 2014

Two diastereoisomers of cyclo(Pro-Tyr) have been synthesized simultaneously. The crystal structures and conformations of both cyclo($\small{L}$-Pro-$\small{L}$-Tyr) and a racemic mixture of cyclo($\small{D}$-Pro-$\small{L}$-Tyr) and cyclo($\small{L}$-Pro-$\small{D}$-Tyr), abbreviated as rac-cyclo($\small{D}$-Pro-$\small{L}$-Tyr/$\small{L}$-Pro-$\small{D}$-Tyr), have been determined by a single-crystal X-ray diffraction study at low temperature. The crystals of rac-cyclo($\small{D}$-Pro-$\small{L}$-Tyr/$\small{L}$-Pro-$\small{D}$-Tyr) belong to orthorhombic space group $Pna2_1$ with a = 10.755 (1), b = 12.699 (1), c = 9.600 (1) ${\AA}$ and Z = 4. The tyrosine side chain is folded towards the diketopiperazine (DKP) ring. The DKP ring adopts a twist boat conformation with pseudo symmetry $C_{2v}$. The pyrrolidine ring has an envelope conformation with the N5, C4, C7 and C8 atoms in a plane. The crystal of rac-cyclo($\small{D}$-Pro-$\small{L}$-Tyr/$\small{L}$-Pro-$\small{D}$-Tyr) is stabilized by hydrogen bonds between amide N2-H2 and carbonyl oxygen O2 in the neighbor. The hydroxyl group of tyrosine residue is also hydrogen bonded to the oxygen of the carbonyl group of the DKP ring in the next molecule. The spectroscopic properties of both isomers are also described.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.4
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• pp.679-687
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• 2017

In this paper, a microstrip-fed triple-band monopole antenna with DGS (Defected Ground Structure) for WLAN/WiMAX applications was proposed. The proposed antenna is based on a microstrip-fed structure, and composed of two strip lines and DGS structure and then designed in order to get triple band characteristics. We carried out simulation about parameters. Adjusted the position and length of the two strips and three slits, we get the optimized parameters. The proposed antenna is fabricated on an FR-4 substrate of which the dielectric constant is 4.4, and its overall size is $34mm(W_1){\times}34mm(L_1){\times}1.6mm(t)$, and its proposed antenna size is $17.0mm(W_6){\times}30.75mm(L_3+L_4+L_9)$. From the fabricated and measured results, return loss of the proposed antenna satisfied return loss -10dB bandwidth 360 MHz (2.335~2.695 GHz), 645 MHz (3.37~4.015 GHz) and 1,770 MHz (5.14~6.91 GHz). And measured results of gain and radiation patterns characteristics displayed for operating bands.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.2
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• pp.246-251
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• 2013

In this paper, we consider the stability of linear systems without delay decomposition. A less conservative result obtained without delay decomposition is strongly required since it is a basis to get an improved result by applying simple delay decomposition. Unlike the most popular Lyapunov-Krasovski(L-K) function, we consider the cross terms between variables. Based on this new structure of L-K function, we derive a delay-dependent stability criterion in the form of linear matrix inequality(LMI). Finally, we show, by well-known two examples, that our result is less conservative than the recent results.

• Bulletin of the Korean Chemical Society
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• v.19 no.11
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• pp.1175-1179
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• 1998

The aerobic reaction of 2-(acetylpyridine)-S-methyldithiocarbazate (acpy-mdtcH) and 2-(acetylpyridine)-N-phenylthiosemicarbazate(acpy-phTscH) with manganese(Ⅱ) acetate affords Mn(acpy-mdtc)2 and Mn(acpyphTsc)2, respectively. The spectroscopic data and X-ray structure of Mn(acpy-mdtc)2 are reported. Crystal data for Mn(acpy-mdtc)2; C18H20N6S4Mn, mol wt 503.58, monoclinic crystal system(P21/c) a=12.240(5) Å, b= 10.918(l) Å, c=17.651(3) Å, β=105.93(2), and V=2268(l) Å3, Z=4, 5071 data collected with 0°< 2θ < 52.64°, 2995 data with I > 3σ(I), R= 0.046, Rw= 0.065. The ligands act as tridentate NNS donors. The two Mn-S distances are not equal, and respectively 2.512(2) Å and 2.541(2) Å. The average Mn-N (azomethine) length, 2.242(5) Å, is slightly shorter than the average Mn-N (pyridyl) length, 2.262(5) Å. The coordination environment about MN(Ⅱ) center deviates considerably from octahedral geometry. The manganese(Ⅱ)-manganese(Ⅰ) and manganese(Ⅰ)-manganese(0) reduction potentials of Mn(acpy-mdtc)2 are ∼-l.71 and ∼-l.98 V while those of Mn(acpy-phTsc)2 are ∼-l.87 and ∼-2.11 V vs. Ag/Ag+ in dimethyl sulfoxide, respectively.