• Title/Summary/Keyword: between two environments

Search Result 923, Processing Time 0.026 seconds

The optimal balance between sexual and asexual reproduction in variable environments: a systematic review

  • Yang, Yun Young;Kim, Jae Geun
    • Journal of Ecology and Environment
    • /
    • v.40 no.2
    • /
    • pp.89-106
    • /
    • 2016
  • Many plant species have two modes of reproduction: sexual and asexual. Both modes of reproduction have often been viewed as adaptations to temporally or spatially variable environments. The plant should adjust partitioning to match changes in the estimated success of the two reproductive modes. Perennial plants showed that favorable habitats in soil nutrients or water content tend to promote clonal growth over sexual reproduction. In contrast, under high light-quantity conditions, clonal plants tend to allocate more biomass to sexual reproduction and less to clonal propagation. On the other hand, plants with chasmogamous and cleistogamous flowers provides with a greater tendency of the opportunity to ensure some seed set in any stressful environmental conditions such as low light, low soil nutrients, or low soil moisture. It is considered that vegetative reproduction has high competitive ability and is the major means to expand established population of perennial plants, whereas cleistogamous reproduction is insurance to persist in stressful sites due to being strong. Chasmogamous reproduction mainly enhances established and new population. Therefore, the functions of sexual and asexual propagules of perennial or annual plants differ from each other. These traits of propagule thus determine its success at a particular region of any environmental gradients. Eventually, if environmental resources or stress levels change in either space or time, species composition will probably also change. The reason based on which the plants differ with respect to favored reproduction modes in each environmental condition, may be involved in their specific realized niche.

Transmission Techniques for Downlink Multi-Antenna MC-CDMA Systems in a Beyond-3G Context

  • Portier Fabrice;Raos Ivana;Silva Adao;Baudais Jean-Yves;Helard Jean-Francois;Gameiro Atilio;Zazo Santiago
    • Journal of Communications and Networks
    • /
    • v.7 no.2
    • /
    • pp.157-170
    • /
    • 2005
  • The combination of multiple antennas and multi-carrier code division multiple-access (MC-CDMA) is a strong candidate for the downlink of the next generation mobile communications. The study of such systems in scenarios that model real-life trans-missions is an additional step towards an optimized achievement. We consider a realistic MIMO channel with two or four transmit antennas and up to two receive antennas, and channel state information (CSI) mismatches. Depending on the mobile terminal (MT) class, its number of antennas or complexity allowed, different data-rates are proposed with turbo-coding and asymptotic spectral efficiencies from 1 to 4.5 bit/s/Hz, using three algorithms developed within the European IST-MATRICE project. These algorithms can be classified according to the degree of CSI at base-station (BS): i) Transmit space-frequency prefiltering based on constrained zero-forcing algorithm with complete CSI at BS; ii) transmit beamforming based on spatial correlation matrix estimation from partial CSI at BS; iii) orthogonal space-time block coding based on Alamouti scheme without CSI at BS. All presented schemes require a reasonable complexity at MT, and are compatible with a single-antenna receiver. A choice between these algorithms is proposed in order to significantly improve the performance of MC-CDMA and to cover the different environments considered for the next generation cellular systems. For beyond-3G, we propose prefiltering for indoor and pedestrian microcell environments, beamforming for suburban macrocells including high-speed train, and space-time coding for urban conditions with moderate to high speeds.

Genetics, Agronomic, and Molecular Study of Leaflet Mutants in Mungbean(Vigna radiata(L.) Wilczek)

  • Soehendi, Rudy;Chanprame, Sontichai;Toojinda, Theerayut;Ngampongsai, Sumana;Srinives, Peerasak
    • Journal of Crop Science and Biotechnology
    • /
    • v.10 no.3
    • /
    • pp.193-200
    • /
    • 2007
  • Mungbean plants generally have a relatively close canopy, thus a large amount of self-shading can reduce yield due to poor light penetration. Modification of leaflet type can affect leaf canopy and could alter seed yield. Two multiple leaflet mutants were obtained from gamma-ray irradiation and used to study the mode of inheritance related to leaflet types and to evaluate their agronomic features. The cross between large-heptafoliate leaflet with small-pentafoliate leaflet mutants produce all $F_1$ plants with normal trifoliate leaflets. The $F_2$ plants segregated in leaflet size and leaflet number into a 9:3:3:1 ratio of large-trifoliate: large-heptafoliate: small-pentafoliate: small-heptafoliate plants, suggesting that independent loci control leaflet size and leaflet number. Regarding leaflet number, the $F_2$ population can be classified into normal-trifoliate, small-pentafoliate, large-heptafoliate, and small-heptafoliate at the dihybrid ratio of 9:3:3:1. The gene symbols $N_1,n_1$ and $N_2,n_2$ are proposed to represent leaflet number. Since no plant was found with large-pentafoliate leaflets, we hypothesize that the $N_2$ allele expresses pleiotropic effect on both leaflet number and leaflet size. Another possibility is that an additional locus with S and s alleles controls leaflet size and S is tightly linked with $N_2$. The effect of multifoliate leaflet on yield and yield components was evaluated in four mungbean families each with four leaflet isolines under three environments. Averaging across the families and environments, the normal-trifoliate and large-heptafoliate lines gave higher yield than small pentafoliate and heptafoliate ones. These two large leaflet lines also had higher leaf area per plant than the other multifoliate lines. Therefore, the mungbean lines with a greater leaf area, which were likely to intercept more sunlight, gave greater yield. Three AFLP markers that were found to be linked to number of leaflets per leaf, corresponded to the N1 allele of the smallpentafoliate parent.

  • PDF

The Characterization of Carbonyl Compounds in the Newly-Built Schools, Daegu City (대구지역 신축학교 실내공기 중 카보닐화합물의 농도 특성 평가)

  • Hwang, Yoon-Jung;Park, Hee-Sun;Jang, Seong-Il;Roh, Ki-Cheul;Son, Tae-Jung;Han, Jeong-Wook;Bae, Gi-Soo;Choi, Im-Jo
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.22 no.6
    • /
    • pp.831-841
    • /
    • 2006
  • The study on school indoor air quality was carried out at classrooms, computer-rooms, laboratories and play- grounds for carbonyl compounds including formaldehyde during the winter time from November to December 2004 and during the summer time from June to July 2005. The sampling was conducted under the general school condition without any artificial intervention such as the sealing, ventilating or heating at indoor environments. The concentrations of formaldehyde at all types of indoor environments were lower than air quality standard of $120{\mu}g/m^3$ for public facilities. The mean concentrations of formaldehyde at indoors were $4.5{\sim}6.1$ times higher than those at outdoors. From the comparison between two year and one year old schools after construction, the concentrations of formaldehyde in two year old school were $30{\sim}38%$ lower than those in one year old school measured at classrooms and laboratories.

Xi Jinping's Visit to South Korea and Its Implications (시진핑(習近平) 국가주석의 방한과 한·중 미래 전략적 협력 동반자 관계)

  • Shin, Jung-Seung
    • Strategy21
    • /
    • s.34
    • /
    • pp.5-25
    • /
    • 2014
  • On July 3~4, 2014, the Chinese President Xi Jinping's state visit to Seoul might be seen as a step on the path toward strategic outcomes for both country. For South Korea, Seoul shrewdly retains some degree of self-reliance by balancing between ROK-China strategic cooperative partnership relationship and ROK-US alliance. For China, Beijing appears to put its interests on the Korean Peninsula increasingly within China's larger geopolitical influence. To what extent can ROK-China relationship maintain futuristic strategic cooperative partnership between them? As we observed joint press communiques of the Chinese President Xi Jinping's state visit on July 3, 2014, four agendas of bilateral relationship between Seoul and Beijing can be identified: intractable rivalry between the two great powers, North Korea nuclear issues, disparities of their displeasure with Japan denying the past wrongdoing and enhancing its military capabilities and Chinese imposing of its core interests on its Korea policy. With these evolving strategic environments, however, China and the ROK appear justifiably be pleased with the state of their relations: their strategic cooperative partnership is the cornerstone of peace and prosperity in the Asia-Pacific or Indo-Pacific region and continues to grow broader and deeper.

Difference of Expressed Character Strengths, the Type of Work : Classification as Per the Korean Strength Scale (한국인 강점 척도를 기반으로 한 업무 유형에 따른 대표 강점 발현의 차이)

  • Kim, Ji-Eun;Kwon, Ye-Ji;Ran, Na-Hae;Lee, Ji-Eun;Noh, Jae-Heung;Chae, Jeong-Ho
    • Anxiety and mood
    • /
    • v.12 no.1
    • /
    • pp.13-20
    • /
    • 2016
  • Objective : The purpose of this study was to verify the differences of expressed character strengths graded as per the Korean Strength Scale, based on the type of work. Methods : A total of 2,444 conglomerate workers were classified into two groups: 1,356 office workers and 1,088 production workers. The subjects were examined through a web or mobile application based on the Korean Strength Scale. The Korean Strength Scale consists of a total of four top entries and 25 sub-items with appropriate validity. Results : The difference in the average score of sum of character strengths between the two groups was not significant. In the office worker group, character strengths such as love of learning, creativity, perspective, curiosity, facilitation, judgment and faith had significantly high scores. On the other hands, modesty, hope, gratitude, sincerity, magnanimity and self-regulation were high in the production worker group. The results remained unchanged in additional analysis of covariants as sex, age and education level, except for self-regulation and faith. Conclusion : Our results suggest significant differences in the character strengths between the two types of work; however, the average of sum of character strength score remains unchanged. These results may help to understand differences between work environments and thus help to establish a positive foundation.

  • PDF

Effects of Cervical Instability on Function of Deep Neck Flexor Muscle and Muscle Tonus of Neck Muscles (목 불안정성이 깊은목굽힘근의 기능과 목 근육들의 긴장도에 미치는 영향)

  • Lee, Sung-Hyun;Seo, Dong-Kwon
    • Journal of The Korean Society of Integrative Medicine
    • /
    • v.9 no.1
    • /
    • pp.123-131
    • /
    • 2021
  • Purpose : The time spent using smart devices is constantly increasing, particularly in recent times. Using smart devices for a long time with an incorrect posture may lead to cerebral palsy (CP), instability, and abnormal muscle tone. Therefore, we aimed to investigate the relationships among cervical instability, deep neck flexor (DNF) activity, range of motion (ROM), and muscle tonus. Methods : Fifty subjects with CP participated in this study, and they were physiotherapists at W Hospital in Daejeon. Those who voluntarily participated in the research were selected as candidates who fulfilled the selection criteria. According to an instability test, 25 subjects were assigned to the instability and control groups. All subjects first underwent the instability test to be allocated to the appropriate group. Those in the instability group tested positive on the instability test. The Neck Disability Index (NDI), ROM, muscle tone, and DNF activity were measured to evaluate their relationships. The DNF strength and endurance were measured using a cranio-cervical flexion test. The upper trapezius (UT), sternocleidomastoid (SCM), and suboccipital (SO) muscle tones were measured using a contact soft tissue tone measuring instrument. The statistical significance level was set to .05. Results : There were significant differences in the flexion, extension, and rotation of the cervical ROM (CROM) between the two groups (p<.05). The SCM, UT, and SO muscle tones were significantly different between the two groups (p<.05). The DNF strength and endurance showed a significant difference between the two groups (p<.05). Conclusion : We found that there were significant increases in the CROM and muscle tone and decrease in the DNF strength and endurance in the instability group. This indicated that cervical instability is affected by the DNF strength and endurance. We may recommend DNF exercises in cases of cervical instability in clinical environments.

Measurement-Based Stochastic Cross-Correlation Models of a Multilink Channel in Cooperative Communication Environments

  • Park, Jae-Joon;Kim, Myung-Don;Kwon, Heon-Kook;Chung, Hyun Kyu;Yin, Xuefeng;Fu, Yaoyao
    • ETRI Journal
    • /
    • v.34 no.6
    • /
    • pp.858-868
    • /
    • 2012
  • In this paper, stochastic models for the cross-correlation of multiple channels are established based on measurement data collected using a wideband multiple-input multiple-output relay Band Exploration and Channel Sounder system at 3.7 GHz. We propose models for the cross-correlation characteristics of large-scale parameters (LSPs) between two links, that is, the base station and mobile station (MS) link and the relay station and MS link. The LSPs include shadow fading, Rician K-factor, delay spread, angle spread of arrival, and angle spread of departure. Furthermore, models are established for the cross-correlation of the small-scale fading in the impulse responses of two links. The statistics of these model parameters are investigated as functions of geometrical features of the multilink. They are extracted from a large amount of cross-correlation observations, which are obtained in three measurement sites along more than one hundred measurement routes. These models can be used together with the standard single-link channel models for the generation of correlated components, for example, path clusters, in two separate channels.

Exploring Effects of Appropriation on the Compliance Intention to Information Security Policy (정보보호 정책의 전유과정이 정보보호 준수의도에 미치는 영향에 대한 탐색적 연구 : 콜센터와 병원 종사자들을 중심으로)

  • Oh, Jinwouk;Baek, Seung Ik
    • Journal of Information Technology Services
    • /
    • v.19 no.5
    • /
    • pp.15-31
    • /
    • 2020
  • This study explores the process in which employees adopt the information security policy. The results of this study, which surveyed 234 employees in three call centers and four hospitals, show that the employees adapt the information security policy through the social structuring process suggested by the AST model. In particular, this study identifies roles of two appropriation activities (FOA : Faithfulness of Appropriation & COA : Consensus on Appropriation) observed in the social structuring process. Regarding to the interactions between the two appropriation activities, FOA, which indicates a better understanding of the information security policy, is examined as a more critical factor than COA, which indicates the degree of agreement among employees about how to use it. FOA not only has a direct effect on compliance intention toward the information security policy, but also indirectly through COA, whereas COA has only a indirect effect through FOA. This result shows that, in order for a company to successfully implement a new information security policy, it is important for employees to understand its purpose and intention. The adaption of information security policy through two appropriation activities is observed in both hospitals and call centers, but due to the different working environments, there were differences in the preceding variables affecting the appropriation activities. The results of this study are expected to provide guidelines for companies who want to successfully adopt information security policy.

Using Korean Phonetic Alphabet (KPA) in Teaching English Stop Sounds to Koreans

  • Jo, Un-Il
    • Proceedings of the KSPS conference
    • /
    • 2000.07a
    • /
    • pp.165-165
    • /
    • 2000
  • In the phoneme level, English stop sounds are classified with the feature of 'voicing': voiceless and voiced (p/b, t/d, k/g). But when realized, a voiceless stop is not alwats the same sound. For example, the two 'p' sounds in 'people' are different. The former is pronounced with much aspiration, while the latter without it. This allophonic differnece between [$P^h$] and [p] out of an English phoneme /p/ can be well explained to Koreans because in Korean these two sounds exist as two different phonemes {/ㅍ/ and /ㅃ/ respectively). But difficulties lie in teaching the English voiced stop sounds (/b, d, g/) to Koreans because in Korean voiced stops do not exist as phonemes but as allophones of lenis sounds (/ㅂ, ㄷ, ㄱ/). For example, the narrow transcription of '바보' (a fool) is [baboo]. In the word initial position, Korean lenis stops are pronounced voiceless and even with a slight aspiration while in the inrervocalic environments they become voiced, That is in Korean voiced stops do not occur independently and neither they have their own letters. To explain all these more effectively to Koreans, it is very helpful to use Korean Phenetic Alphabet (KPA) which is devised by Dr. LEE Hyunbok (a professor of phonetics at Seoul National Univ. and chairman of Phonetic Society of Koera.)(omitted)

  • PDF