• Title/Summary/Keyword: Directional Difference

Search Result 229, Processing Time 0.025 seconds

Adolescents' online and offline socializing and delinquent behaviors: Cross-domain influences (청소년의 온라인과 오프라인 교우활동과 비행행동 간의 상호영향 분석)

  • Kim, Hyoseon;Moon, Ui Jeong;Shim, Hee Sub
    • Korean Journal of Family Welfare
    • /
    • v.23 no.4
    • /
    • pp.575-593
    • /
    • 2018
  • Online and offline are not separate worlds, especially for adolescents. Many friends in offline settings originally met each other online, but cross-domain influences have rarely been examined. This study aims to examine how much time adolescents spend with peers in online and offline settings, and how time spent with peers influences their online and offline delinquent behaviors during their middle school years. This study used data from the Korean Children & Youth Panel Survey (KCYPS). We focused on students for whom information was available from all three years of middle school. We used a cross-lagged panel model to examine the bi-directional effect of online and offline behaviors over time. Results show that more time spent with peers offline was associated with more offline delinquency, and more time spent with peers online was associated with more online delinquency. Cross-domain influences were also found: more time with peers offline increased online delinquency, and vice versa. However, this adverse cross-domain influence was observed only for male adolescents, not for female adolescents. Implications for intervention programs are discussed for male and female adolescents.

The Role of Remittances in Financial Development: Evidence from Nonlinear ARDL and Asymmetric Causality

  • MEHTA, Ahmed Muneeb;QAMRUZZAMAN, Md.;SERFRAZ, Ayesha;ALI, Asad
    • The Journal of Asian Finance, Economics and Business
    • /
    • v.8 no.3
    • /
    • pp.139-154
    • /
    • 2021
  • This study's impetus is to explore fresh evidence to answer the question, i.e., whether remittances asymmetrically influence financial development in Bangladesh from 1975 to 2019. The study employs several tests, i.e., nonlinear unit root test, Autoregressive Distributed Lagged (ARDL), NARDL, and asymmetric causality test for establishing the pattern of association. Nonlinear unit root tests confirm that variables follow a nonlinear system of being stationary after the first difference. nonlinearity among variables is investigated by performing the BDS test and nonlinear OLS. Directional causality is investigated through both linear and nonlinear effects of remittance inflows by following the non-granger casualty test. The test statistics of Fpass and tBDM showed the Long-run cointegration in the empirical model and positive effect running from remittances inflow to financial development both in the long-run and short-run. Furthermore, the results of a standard Wald test divulge the presence of long-run and short-run asymmetry. Asymmetry causality test established unidirectional causality due to positive and negative shocks in remittances inflows to Bank-based financial development and feedback hypothesis hold for explaining causality between positive and negative shocks in remittance inflows and Stock-based financial development.

Symmetric and Asymmetric Effects of Financial Innovation and FDI on Exchange Rate Volatility: Evidence from South Asian Countries

  • QAMRUZZAMAN, Md.;MEHTA, Ahmed Muneeb;KHALID, Rimsha;SERFRAZ, Ayesha;SALEEM, Hina
    • The Journal of Asian Finance, Economics and Business
    • /
    • v.8 no.1
    • /
    • pp.23-36
    • /
    • 2021
  • The study explores the nexus between foreign direct investment (FDI), financial innovation, and exchange rate volatility in selected South Asian countries for 1980 to 2017. The study applies the unit root test, Autoregressive Distributed Lagged, nonlinear ARDL, and causality test following Toda-Yamamoto. Unit root tests ascertain that variables are integrated in a mixed order; few variables are stationary at a level and few after the first difference. Empirical model estimation with ARDL, Long-run cointegration revealed with the tests of FPSS, WPSS, and tBDM by rejecting the null hypothesis of "no cointegration." This finding suggests that, in the long-run financial innovation, FDI inflows, and exchange rate volatility move together. Moreover, study findings established adverse effects running from FDI inflows and financial innovation to exchange rate volatility in the long run. These findings suggest that continual FDI inflows and innovativeness in the financial system assist in lessening the volatility in the foreign exchange market. Furthermore, nonlinear ARDL confirms the presence of asymmetric cointegration in the model. The standard Wald test established asymmetric effects running from FDI inflows and financial innovation to exchange rate volatility, both in the long and short run. Directional causality unveils feedback hypothesis holds for explaining causality between FDI, financial innovation, and exchange rate volatility.

Functional Haplotypes and Evolutionary Analyses of SBE1 in Collected Rice Germplasm

  • Thant Zin Maung;Yong-Jin Park
    • Proceedings of the Korean Society of Crop Science Conference
    • /
    • 2022.10a
    • /
    • pp.216-216
    • /
    • 2022
  • The starch-branching enzymes (BEs) are responsible for synthesizing the amylopectin, which plays an important role in determining the structural and physical properties of starch granules. BE has two differently functioning isoforms (BEI and BEIIa/b) based on their difference in the chain-length pattern by the degree of polymerization (DP), which mainly contributes to the amylopectin chain length distribution in starch biosynthesis. In this study, we investigated functional haplotypes and evolutionary analyses of SBE1 in 374 rice accessions (320 Korean bred and 54 wild). The analyses were performed based on the classified subpopulations. Haplotype analysis generates a total of 8 haplotypes, of which only four haplotypes were functional carrying four functional SNPs in four different exons of SBE1 on chromosome 6. Nucleotide diversity analysis showed a highest pi-value in aromatic group (0.0029), while the lowest diversity value was in temperate japonica (0.0002), indicating the signal of this gene evolution origin. Different directional selections could be estimated by negative Tajima's D value of temperate japonica (-1.1285) and positive Tajima's D value of tropical japonica (0.9456), where the selective sweeps were undergone by both positive purifying and balancing selections. Phylogenetic analysis indicates a closer relationship of the wild with most of the cultivated subgroups indicating a common ancestor for SBE1 gene. FST-values indicate distant genetic relationships of temperate japonica from all other classified groups. PCA and population structure analysis show an admixed structure of wild and cultivated subpopulations in some proportions.

  • PDF

PRELIMINARY STUDY OF NEUROSENSORY RECOVERY AFTER BSSRO (악교정 수술 후 발생하는 신경회복에 대한 연구 I)

  • Lee, Dong- Keun;Jo, I-Su;Min, Seung-Ki;Oh, Seung-Hwan;Jeong, Chang-Ju;Lee, Eun-Tak
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.23 no.2
    • /
    • pp.144-154
    • /
    • 2001
  • Dysfunction of the inferior alveolar nerve indicated by various degree of numbness of the lower lip and chin is one of the few drawbacks of mandibular osteotomy, especially Bilateral Sagittal Split Ramus Osteotomy(BSSRO) and genioplasty. Although it has been recorded throughout the history of this techniques, it is true etiology poorly understood. In this study, 22 consecutive patients under class III malocclusiion impression and undergoing orthognathic surgery(BSSRO only 11 case, BSSRO with genioplasty 11 case) were studied using 4 neurosensory test(static light touch, directional discrimination, two-point discrimination, pin pressure nociception) with post OP 1 week, 2 weeks, 4 weeks, 8 weeks, 12 weeks, 24 weeks, On control group, 10 members without trauma and nerve damage history, nerve test was accomplished. We concluded majority of patients return of sensation during post operative 24 weeks. Althought immediate nerve deficit are 92.2%, 97.2% 88.9% these are recovered to 25%, 35.72%, 10.71% at 24 weeks. Nerve recovery rate increased prominently between post 4 weeks and 8 weeks. There is no statistically difference about neurosensory deficit among the chin area. Neurosensory deficit more severe when the BSSRO with genioplasty group than the only BSSRO group. Immediate neurosensory deficit is larger left side than right side but after 6 months, there is no significantly difference between left side and right side. Static light touch and pin pressure nociception are more sensitive method of neurosensory deficit than two point discrimination.

  • PDF

Design of a KaBand Half-Height Waveguide Power Combiner (Ka-Band용 Half-Height Waveguide 전력 합성기 설계)

  • 빅필준;최재훈
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.11 no.7
    • /
    • pp.1218-1224
    • /
    • 2000
  • A half-height waveguide power combiner is designed and analyzed for Ka-band satellite application. The branch line directional coupler is utilized as a power combiner to achieve high port-to-port isolation and low insertion loss. The half height waveguide is adopted to reduce the volume and mass of a power combiner. In this paper a half height waveguide power combiner is designed and analyzed by FDTD and its performance is compared with that of a full-height waveguide power combiner. The designed half-height combiner having optimum order is manufactured and tested. The measurement shows that the designed half-height power combiner satisfies all the performance requirements (insertion loss less than 0.3 dB, reflection loss more than 20dB, port to port isolation more than 20 dB, and port to port phase difference within 5$^{\circ}$) in the satellite communication frequency band of 20.255 GHz to 21.255 GHz.

  • PDF

The effects of a temporal masking on the sound laterlization (시간 마스킹이 음상정위에 미치는 영향)

  • Lee, Chai-Bong
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.5 no.4
    • /
    • pp.352-356
    • /
    • 2010
  • In this study, it is discussed how the directional property of the sound lateralization is influenced by proceeding or succeeding tone. The acoustic source applied here is a reference sound which has 0.5 msec interaural time difference(ITD). Based on this reference sound, interfering sounds with five levels of magnitude are applied to the subjects with four kinds of inter-stimuli time intervals(ISI). The interfering sounds are also added as two different types, proceeding tone and succeeding tone. Additionally, in order to investigate a frequency influence, the reference sound and the interfering sounds are generated by using 2kHz, 4 kHz and a white noise. As a result, the influence on lateralization by proceeding tone is lager than that by succeeding tone. It can consider this result as the effect of temporal masking on lateralization. Moreover, there are small differences of masking effect on lateralization by combinations of pure tone. This result shows that the dependency of frequency domain between reference sound and interfering sound is small on the sound lateralization.

Location Estimation Algorithm Based on AOA Using a RSSI Difference in Indoor Environment (실내 환경에서 RSSI 차이를 이용한 AOA 기반 위치 추정 알고리즘)

  • Jung, Young-Jin;Jeon, Min-Ho;Ahn, Jeong-Kil;Lee, Jung-Hoon;Oh, Chang-Heon
    • Journal of Advanced Navigation Technology
    • /
    • v.19 no.6
    • /
    • pp.558-563
    • /
    • 2015
  • There have recently been various services that use indoor location estimation technologies. Representative methods of location estimation include fingerprinting and triangulation, but they lack accuracy. Various kinds of research which apply existing location estimation methods like AOA, TOA, and TDOA are being done to solve this problem. In this paper, we study the location estimation algorithm based on AOA using a RSSI difference in indoor environments. We assume that there is a single AP with four antennas, and estimate the angle of arrival based on the RSSI value to apply the AOA algorithm. To compensate for RSSI, we use a recursive averaging filter, and use the corrected RSSI and the Pythagorean theorem to estimate the angle of arrival. The results of the experiment, show an error of 18% because of the radiation pattern of the four non-directional antennas arranged at narrow intervals.

Adaptive spatio-temporal deinterlacting algorithm based on bi-directional motion compensation (양방향 움직임 기반의 시공간 적응형 디인터레이싱 기법)

  • Lee, Sung-Gyu;Lee, Dong-Ho
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.39 no.4
    • /
    • pp.418-428
    • /
    • 2002
  • In this paper, we propose a motion-adaptive de-interlacing method using motion compensated interpolation. In a conventional motion compensated method, a simple pre-filter such as line averaging is applied to interpolate missing lines before the motion estimation. However, this method causes interpolation error because of inaccurate motion estimation and compensation. In the proposed method, EBMF(Edge Based Median Filter) as a pre-filter is applied, and new matching method, which uses two same-parity fields and opposite-parity field as references, is proposed. For further improvement, motion correction filter is proposed to reduce the interpolation error caused by incorrect motion. Simulation results show that the proposed method provides better performance than existing methods.

Secondary Residual Transform for Lossless Intra Coding in HEVC (제 2차 잔차 변환을 이용한 HEVC 무손실 인트라 코딩)

  • Kwak, Jae-Hee;Lee, Yung-Lyul
    • Journal of Broadcast Engineering
    • /
    • v.17 no.5
    • /
    • pp.734-741
    • /
    • 2012
  • A new lossless intra coding method based on residual transform is applied to the next generation video coding standard HEVC (High Efficiency Video Coding). HEVC includes a multi-directional spatial prediction method to reduce spatial redundancy by using neighboring samples as a prediction for the samples in a block of data to be encoded. In the new lossless intra coding method, the spatial prediction is performed as samplewise DPCM (Difference Pulse Code Modulation) but is implemented as block-based manner by using residual transform and secondary residual transform on the HEVC standard. Experimental results show that the new lossless intra coding method reduces the bit rate by approximately 6.45% in comparison with the lossless intra coding method previously included in the HEVC standard.