• 제목/요약/키워드: dominant period

검색결과 1,136건 처리시간 0.036초

자동차 타이어 손상에 의한 초음파 신호 주기 측정에 관한 연구 (On the Study of the Period Measurement of Ultrasonic Signal in Damaged Vehicle Tire)

  • 박정임;임승각;강대수
    • 한국인터넷방송통신학회논문지
    • /
    • 제11권5호
    • /
    • pp.47-52
    • /
    • 2011
  • 본 논문에서는 주행 중 타이어와 노면이 마찰하면서 발생하는 초음파 신호에서 이물질로 인해 야기되는 우성주기를 검출하여 타이어 손상 유무를 판별하는 알고리즘에 대해 연구하였다. 손상된 타이어에서 획득한 초음파 신호의 포락선에 대해 전력스펙트럼을 산출하고 통계적 처리에 의한 임계값을 설정함으로써 우성주기를 판별하는 알고리즘을 제안하였다. 모의실험 결과, 시속 80km/h로 주행 시 초음파 신호의 포락선에 대해 전력스펙트럼의 피크주기 97.6ms에 비해 제안된 알고리즘의 우성주기는 100ms로서 포락선 피크의 평균주기 101.24ms를 기준으로 하였을 때 더 정확한 주기 측정 결과를 보였다.

낙동강 하류지역의 식물플랑크톤 우점종 군집 변화: 2002년~2012년 (Changes of Dominant Phytoplankton Community in Downstream of the Nakdong River: From 2002 to 2012)

  • 손희종
    • 대한환경공학회지
    • /
    • 제35권4호
    • /
    • pp.289-293
    • /
    • 2013
  • 2002년부터 2012년까지 낙동강 하류 물금지역에서의 식물플랑크톤 우점종의 군집비율 변화를 조사한 결과, 식물플랑크톤 생체량(클로로필-a 농도)은 점진적인 감소 추세였던 반면, 우점종의 개체수는 증가 추세를 나타내었다. 식물플랑크톤 종별로 우점종의 연도별 개체수 비율변화에서 규조류는 감소 추세를 보인 반면, 남조류는 증가 추세를 나타내었다. 또한, 우점기간의 경우 매년 우점기간의 75% 이상을 규조류가 차지하였다. 연중 식물플랑크톤 비율변화에서 규조류는 11월에서 5월까지 매우 높은 우점비율을 보였고, 6월부터 9월까지도 우점일수의 56%~74%를 차지하여 연중 규조류가 300일 정도 우점하였다. 남조류는 6월부터 9월까지 개체수 및 우점기간의 68%~94% 및 26%~36%를 차지하였으며, 녹조류는 4월부터 9월까지 낮은 우점률을 나타내었다. 규조류와 남조류 우점종들의 연중 천이패턴은 규조류의 경우 12월~5월은 Stephanodiscus spp., 5월~10월은 Aulacoseira spp.와 Fragilaria spp.가 대부분 우점하였으며, 남조류의 경우 5월~11월에 Microcystis spp.가 대부분을 우점하였다. 또한, 녹조류는 4월~9월에 Actinastrum spp., Pediastrum spp., Micractinium spp. 및 Pandorina spp.가 우점하였다.

손 기능 훈련이 손의 기민성에 미치는 영향 (The Effect of Hand Function Training on Hand Dexterity)

  • 장철;이제영;송민옥
    • 대한통합의학회지
    • /
    • 제3권4호
    • /
    • pp.11-21
    • /
    • 2015
  • Purpose : The purpose of this study was to provide the material about the treatment effect of hand function training and writing training being performed as a part of treatment to improve the function of the non-dominant hand of the patients whose dominant hand is damaged and thus need to improve their non-dominant hand's function. Method : During one month of November, 2013, this study randomly chose five study subjects for hand function training, five for writing training, and ten of control group from 20 normal male and female adults going to K Univ. in Busan. All study subjects fully understood all of the training course, agreed to take the test in this study, and volunteered to participate in the test. Each training was performed five times for two weeks, 30 minutes each time. For measurement, Purdue pegboard was used to look into the change of hand dexterity. To investigate an improvement in hand function through hand function training and writing training, this study conducted early evaluation before training, interim evaluation, and final evaluation. Result : First, according to the comparison of dominant hand dexterity by group and by method during a training period, the groups of hand function training and of writing training improved dominant hand dexterity more than the control group. Secondly, according to the comparison of non-dominant hand dexterity by group during a training period, the groups of hand function training and of writing training improved dexterity more than the control group. According to the comparison of non-dominant hand dexterity by method during a training period, there was no big difference in dexterity between the groups of hand function training and of writing training and the control group. But, the group of hand function training showed a further improvement. Thirdly, according to the comparison of both-hand dexterity by group and by method during a training period, the groups of hand function training and of writing training improved both-hand dexterity more than the control group. Fourthly, according to the comparison of both-hand handling ability by group and by method during a training period, the groups of hand function training and of writing training improved both-hand handling ability more than the control group. Conclusion : Given the study result, it is considered that hand function training and writing training help brain damaged patients improve their hand function for their daily activity. And it will be meaningful to research brain damaged patients' motor skills after their brain damage, and the patients who have low abilities of visual perception and cognition. In the future, it will be necessary to secure more study subjects and perform systematic training during a sufficient test period.

과제수행을 통한 비우세손 훈련이 손 기능에 미치는 영향 (Effects of the Training of Non-Dominant on Hand Function)

  • 장철;송민옥;김보아;한수정
    • 대한통합의학회지
    • /
    • 제3권4호
    • /
    • pp.1-9
    • /
    • 2015
  • Purpose : We described how the training of non-dominant hand that applicates the activity effects on dominant hand. Method : From November 6th to December 2nd 2013, We randomly selected 18 people that don't have a damage of hand function and are in college of K in Busan. (cross stitch training group 9 people, control group 9 people) All participants agreed on the research after fully being aware of training procedures and spontaneously conducted. Each training was practiced for 40 minutes in once every second day. One researcher deals with three participants at silent environment. We used the study measurement, Purdue pegboard, to investigate the sharpness of hand. To investigate the advancement of hand function caused by cross stitch training, we practiced three times estimations of primary one before training, middle one after 2 weeks training, last one after four weeks training and obtained the following results. Result : First of all, We found that the group of hand training appeared to be advanced of dominant hand's sharpness depending on the training period more than the control group. Second, We found that the group of hand training appeared to be advanced of non-dominant hand's sharpness depending on the training period more than the control group. Third, We found that the group of hand training appeared to be advanced of both hand's sharpness depending on the training period more than the control group. Fourth, We found that the group of hand training appeared to be advanced of the assembling function sharpness depending on the training period more than the control group. Conclusion : Put the results of this research together, we found that non-dominant hand training that used the activity was of help to advance the function of dominant hand. So, we thinks that hand training might help the recovery of affected hand function to the person that have a problem of hand function like hemiplegia patient. It will be required to practice the further study targeting the person that have a problem of hand function like hemiplegia patient. We hope that this research will be apply to clinical occupational therapy.

진해만 동부해역에 출현하는 자치어의 종조성 (Species composition of larval fishes in the eastern Jinhae Bay, Korea)

  • 김현지;정재묵;박종혁;허성회;백근욱
    • 수산해양기술연구
    • /
    • 제54권1호
    • /
    • pp.81-88
    • /
    • 2018
  • A study for species composition and abundance of the fish assemblages in the eastern Jinhae Bay, Korea was conducted using monthly larval collection by a RN80 net from October, 2010 to September, 2011. Of all the 45 species collected, the dominant species were Clupea pallasii, Hexagrammos otakii, Pholis fangi and Engraulis japonicus. Clupea pallasii, Hexagrammos otakii, Pholis fangi in winter and examined Engraulis japonicus, Acanthogobius sp., Parablennius yatabei, and Tridentiger trigonocephalus in summer appeared seasonally. Popoulation characteristic by stations was not clear seasonally and spatially, and appearance aspects of dominant species were similar by stations. Compared our results with other studies in the South Sea, dominant species and their appearance period were similar to their spawning period. Finally, the appearance period of the larvae in the South Sea was closely resulted to spawning period rather than the regional characteristic.

Seasonal Cycle of Phytoplankton in Aquaculture Ponds in Bangladesh

  • Affan, Abu;Jewel, Abu Syed;Haque, Mahfuzul;Khan, Saleha;Lee, Joon-Baek
    • ALGAE
    • /
    • 제20권1호
    • /
    • pp.43-52
    • /
    • 2005
  • A study on the seasonal changes in the phytoplankton community was carried out in four aquaculture ponds of Bangladesh over a period of 16 months from August 2000 to November 2001. Out of 45 phytoplankton species identified, 30 belong to Cyanophyceae, 7 to Chlorophyceae, 5 to Bacillariophyceae and 3 to Euglenophyceae. The highest phytoplankton abundance was observed in spring followed by early autumn, summer, and the lowest was in winter. The annual succession of Cyanophyceae was characterized by spring and early autumn period dominated by Microcystis sp. Anabaena sp. and Planktolymbya sp. with Microcystis sp. as the main blue-green algae represented. Chlorophyceae was characterized by rainy season domination of Chlorella vulgaris, Pediastrum sp. and Scenedesmus denticulatus with maximum abundance of Chlorella vulgaris. Whereas Bacillariophyceae was dominant during the winter period. Navicula angusta and Cyclotella meneghiniana were the most frequently occurring species of Bacillariophyceae throughout the study period. Euglenophyceae was dominant in late autumn and Euglena sp. was the dominant species. The effect of various physicochemical water quality parameters on the seasonal distribution and succession of the above mentioned phytoplankton population as well as the interaction and eutrophication are discussed.

Estimation of the Fundamental Period for Residential Buildings with Shear-Wall System

  • Chun, Young-Soo;Chang, Kug-Kwan;Lee, Li-Hyung
    • KCI Concrete Journal
    • /
    • 제12권1호
    • /
    • pp.121-130
    • /
    • 2000
  • This study focused on evaluating the reliability of code formulas such as those of the current Korean Building Code(KBC 1988). UBC 1997, NBCC 1995. and BSLJ 1994 for estimating the fundamental period of RC apartment buildings with shear-wall dominant systems, representative of typical residential buildings in Korea. For this purpose, full-scale measurements were carried out on fifty RC apartment buildings, and these results were compared to those obtained by code formulas and also by dynamic analysis. Although these code formulas are based on the measured periods of buildings during various earthquakes and building period varies with the amplitude of structural deflection or strain level, ambient surveys should provide an effective tool for experimentally verifying the design period to the completed building. This comparison shows that comparatively large errors are likely to occure when the code formula of KBC 1988 is used, and all the other code formulas are not sufficient to estimate the fundamental period of apartment buildings with shear-wall dominant systems. An improved formula is proposed by regression analysis on the basis of the measured period data. The proposal is for the servicebility stress level, but it can also be applied for seismic code in the regions of low seismicity similar to Korea.

  • PDF

증강현실 기반의 단기간 무릎운동이 관절가동범위와 균형에 미치는 영향 - 예비연구 (The Influence of Augmented Reality based Knee Exercise in Short Period on Range of Motion and Balance - Pilot study)

  • 임종훈;유재호
    • 정형스포츠물리치료학회지
    • /
    • 제14권2호
    • /
    • pp.1-8
    • /
    • 2018
  • Purpose: This study investigated the effect of the augmented reality (AR)-based knee joint short period exercise program and used a motion analyzer with a 3D camera to determine the range of motion and dynamic balance and further investigate the effects of therapeutic exercise on patients. Methods: This study used AR-based motion analysis and a Y-balance test to measure the range of motion (ROM) of each joint: the hip joint and the knee joint. After the measurements, an exercise program was applied to the subjects, using the knee motion program function, and the muscles of the quadriceps femoris and the hamstring were stretched or strengthened. Results: Our results showed knee joint extension at the dominant hip joint flexion position. While there was no significant difference (p>.05) at this position, there were significant differences in the non-dominant hips, unbalanced knee joint flexion, and superior knee joint flexion (p<.05). The Y-balance test using the non-dominant leg supported by the dominant legs showed that the absolute reach was $69.70{\pm}7.06cm$ before the exercise, and the absolute reach after the exercise was $77.56{\pm}6.09cm$ (p<.05). Conclusions: There was a significant difference when the movement of the lower limbs supported the superior limbs, and a significant difference was found in the ROM when the non-dominant side supported the dominant side. Therefore, the AR-based exercise program improves the balance of the human body and the range of motion of the joints, and research that aims to improve patients abilities should continue.

서해 태안반도 북서 연안해역에서의 연안류 특성 (The Characteristics of Coastal Currents to the Northwest of the Taean Peninsula in the Yellow Sea)

  • 신홍렬
    • Ocean and Polar Research
    • /
    • 제27권4호
    • /
    • pp.433-441
    • /
    • 2005
  • To investigate the characteristics of tidal currents and water circulation in the coastal waters off the Taean Peninsula, tidal currents and sea levels were measured at the study area from 1998 to 2004. In the central waterway to the south of Changan Sand Ridge, mean speed of tidal currents and residual currents were 74.0cm/s, 17.8cm/s respectively; the dominant residual currents flowed northeastward, and the amplitudes of semi-diurnal components $(M_2,\;S_2)$ were larger than diurnal components $(O_1,\;K_1)$. The flood and ebb tidal currents were northeastward and southwestward, respectively, and each period was about 6 hours for them, which was consistent with the period of sea levels at the study area. In the coastal region near Hakampo, Taean, mean velocities of tidal currents and residual currents were 46.1cm/s, 30.8cm/s respectively, and the dominant residual currents flowed southwestward. The amplitudes of shallow water constituents $(M_4,\;MS_4)$ were relatively laige, which were weaker to the northeastern coastal region off Mineodo. The northeastward flow continued for about $2{\sim}3$ hours, while the southwestward flow continued for about $9{\sim}10$ hours near Hakampo during the tidal period. Tidal currents flowed northeastward in the central area of the waterway during the period from the Low Water Level (LWL) to the High Water Level (HWL). While the currents in the coastal region flowed northeastward for the first 3 hours after the LWL, southwestward counter-currents flowed between 3 and 6 hours after the LWL. During the period from the HWL to the LWL, the dominant currents flowed southwestward in the study area except to the northeastern coastal region off Mineodo. Along the shorelines, the counter-currents flowed northward between 4 and 6 hours after the HWL. It seems that the counter-currents near the coastal region are caused by the topography and the geography of the shorelines at the study area.

Improving Productive and Reproductive Performance of Holstein Dairy Cows through Dry Period Management

  • Safa, S.;Soleimani, A.;Heravi Moussavi, A.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제26권5호
    • /
    • pp.630-637
    • /
    • 2013
  • To determine the effects of dry period (DP) length on milk yield, milk composition, some blood metabolites, complete blood count (CBC), body weight and score and follicular status, twenty five primiparous and multiparous Holstein cows were assigned to a completely randomized design with DP-60 (n = 13) and DP-20 (n = 12) dry period lengths. Cows in the DP-60 produced more milk, protein, SNF, serum non-esterified fatty acids (NEFA) and beta hydroxyl butyrate acid (BHBA) compared with cows in DP-20 ($p{\leq}0.05$). Serum glucose, blood urea nitrogen (BUN), urea, and glutamic oxaloacetic transaminase (GOT) were all similar among the treatments. Body Condition Score (BCS), body weight (BW), complete blood count (CBC) and health problems were similar between the treatments. Diameter of the first dominant follicle and diameter of the dominant follicle on d 14 were different among the treatments. Thus, results of this study showed that reducing the dry period length to DP-20 had a negative effect on milk production, milk composition and reproductive performance in Holstein dairy cows.