• 대한조선학회논문집
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• 제49권6호
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• pp.478-483
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• 2012

The speed performances of ice sea trial on the Arctic(2010 & 2011) area were shown different results depend on the ice floe size. Penetration phenomena of level ice was not happened on medium ice floe and tore up by the impact force because the mass of medium ice floe is similar to the mass of Araon which is Korean ice breaking research vessel and did not shut up by the ice ridge or iceberg. The sea trial on the Amundsen sea was performed at the big floe which is classified by WMO(World Meteorological Organization). Three measurements of ice properties and five results of speed trial were obtained with different ice thicknesses and engine powers. To evaluate speed of level ice trial and model test results at the same ice thickness and engine power, the correction method of HSVA(Hamburg Ship Model Basin) was used. The thickness, snow effect, flexural strength and friction coefficient were corrected to compare the speed of sea trial. The analyzed speed at 1.03m thickness of big floe was 5.85 knots at 10MW power and it's 6.10 knots at 1.0m ice thickness and the same power. It's bigger than the results of level ice because big floe was also slightly tore up by the impact force of vessel based on the observation of recorded video.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2010년 춘계학술발표회 논문집
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• pp.113-115
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• 2010

We studied the methods to utilize vehicle-based mobile mapping system for field investigation work of digital map generation process. Map layers which should be checked by field investigation were analyzed to find the possibility of being checked with data from vehicle-based mobile mapping system. Also new process for digital map generation were suggested to adopt field investigation by vehicle-based mobile mapping system. We performed field investigation work on the Kangneung area by vehicle-based mobile mapping on a trial bases and compared the results with a results from usual field investigation method.

• 한국통신학회논문지
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• 제36권2B호
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• pp.141-147
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• 2011

본 연구에서는 국내 FM 방송 가용주파수 확보 가능성을 확인하기 위하여 600kHz 채널이격 간격에 대한 동일 송신소 이격실험을 실시하였다. 통일 송신소에서 주파수를 600kHz로 이격할 경우, 수신기를 통한 주관적 음질평가, 전계강도 등의 특성이 비교적 양호한 것으로 평가되어 사전 시뮬레이션 및 충분한 Field Test 등의 사전 분석을 통해 사용할 수 있음을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1658-1660
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• 1994

This paper describes the measurement system of the magnetic field waveforms generated by lightning return strokes. The frequency bandwidth of magnetic field measurement system is from 270[Hz] to about 2.3 [MHz]. As the application experiment, the magnetic field generated by simple impulse and oscillating impulse currents, which are measured by a current transformer (Tek. AM503), is observed by the trial magnetic field measurement system. The obtained results are agreement with each other. A typical magnetic field waveform associated with lightning return strokes was recorded and presented.

• 한국농림기상학회지
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• 제20권4호
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• pp.277-283
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• 2018

기후변화 영향평가를 위해 작물생육모형을 폭넓게 사용하고 있지만 모형을 구동하기 위해서는 품종모수를 결정하는 것이 필수적이다. 그러나 품종모수 결정을 위한 실험은 장시간의 노력이 필요하여 대부분 작황자료 또는 지역적응 시험 자료를 많이 사용하고 있다. 그러나 밭작물의 경우 작황자료 또는 지역적응 시험을 사용하는 경우에는 포장의 관개량과 시기에 대한 자료가 없고 또한 별도의 기상관측 없이 최인접지역의 기상자료를 사용하기 때문에 문제가 발생할 수 있다. CERES-MAIZE를 이용하여 밭작물인 옥수수에 대해서 이 문제점들을 검토하였다. 출사기와 관련된 품종모수는 최대 27km 내에 기상관측 지점이 있는 경우에도 신뢰성있는 품종모수가 얻어졌다. 온도의 경우에는 지형에 따라 유효한 거리가 달라질 수 있지만 본 연구의 대상 지역에서는 품종 모수 추정에 문제가 크지는 않을 것으로 보인다. 또한 온도 이외의 요소인 강수 또는 관개량은 생물계절관련 품종모수와는 큰 영향이 없기 때문에 비교적 정확도가 높은 결과가 나온 것으로 보인다. 그러나 수량과 관련된 품종 모수 요소에서는 그렇지 못하였다. 이는 밭작물의 경우 강수량에 따라 스트레스 정도가 결정되기 때문에 관개 및 강수량 정보가 중요한데, 관개량에 대한 정보를 작황 또는 지적시험 보고서에서는 얻을 수 없기 때문이다. 더구나 강수량의 경우에 온도보다 더 가까운 위치에 기상관측소가 존재해야만 유의미한 정보를 제공할 수 있다. 그러나 시험포장에 따라 기상관측소와의 거리가 충분히 가깝지 않은 경우가 대부분이었다. 따라서, 작황 또는 지역적응 시험자료를 이용하여 옥수수의 품종모수를 결정할 때는 기상관측 지점이 최소한 20km 이내의 인접지역에서 생물계절과 관련된 모수에 대해서만 결정하는 것이 타당할 것으로 생각된다. 그 반면에 수량과 관련된 요소의 결정은 적절하지 않을 것으로 생각된다. 수량과 관련된 요소를 결정하기 위해서는 가급적 직접 기상관측망을 설치하여 해당 포장에서 관개시기와 관개량을 모두 확보한 실험한 결과를 바탕으로 얻는 것이 적절할 것으로 생각된다.

• Korean Journal of Acupuncture
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• 제35권2호
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• pp.70-81
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• 2018

Objectives : To investigate the association of trial registration status with presence of reporting bias including publication bias and outcome reporting bias in recently published randomized controlled trials (RCTs) of acupuncture. Methods : A PubMed search for RCTs of acupuncture published from March 2016 to February 2017 was conducted. Primary outcomes were identified and the direction of the results was judged as positive (i.e., statistically significant) or negative. The trial registration was identified by manually screening the trial registration number in the main text of the published article and classified into 1) prospective registration; 2) retrospective registration based on the registration date or; 3) no registration. Results : Of the 125 included RCTs, only 40 studies (32.0%) prospectively registered the study protocols. Among 65 RCTs that adequately reported the primary outcome, unregistered trials were more likely to report positive results than the registered ones (p=0.013). Of the 40 prospectively registered studies, 19 trials (47.5%) had the discrepancies between the registered and published primary outcomes and furthermore, 40% of them reported the positive findings. Conclusions : Unregistered trials were more likely to report positive results and the discrepancies between the registered and published primary outcomes were detected in about a half of the prospectively registered studies, 42.1% of which tended to report positive findings. Journal editors and researchers in this field should be alerted to various reporting biases.

• 한국임상수의학회지
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• 제40권6호
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• pp.464-467
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• 2023

The autonomic regulation of heart rate (HR) is an indicator of the body's ability to adapt to an exercise stimulus. However, there are no reports on this topic in relation to Jeju horses used for racing. The aim of this study was to analyze the HR responses of Jeju horses during race trials and to investigate the correlation between HR and performance in these horses. HR data were collected from 17 healthy 2- to 7-year-old Jeju horses wearing HR monitors during race trials. Pearson correlation coefficients was used to determine the significance of the association between the race trial time and HR. A significant inverse correlation was observed between the race trial time (performance) and both the maximal HR (HRmax, r = -0.69, p < 0.01) and HR reserve (HRR) (HRmax - average HR during the warm-up period, r = -0.63, p < 0.01) and between the HRR and HRmax (r = 0.73, p < 0.01). Horses with a lower average HR during the warm-up period and higher heart rates during the trial achieved faster race trial times. This study reports the first HR measurements in Jeju horses during race trials, providing new insights into the HR response of this breed to exercise. The use of a noninvasive remote HR monitor system allowed assessment of exercise responses in the field, and the results suggest that both the HRR during warm-up period and HRmax may be useful performance indicators in Jeju horses.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1994년도 춘계공동학술대회논문집; 창원대학교; 08월 09일 Apr. 1994
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• pp.375-384
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• 1994

Depending upon the eye and head movement, the visual field is often classified into three categories; stationary field, eye field and head field. To investigate the effect of background condition on the size of stationary field, an experiment was conducted, in which the subject was instructed to search a target with distinct orientations. In each trial, a single target was presented on the rear-view screen projected by the two-field tachistoscope, with the visual angle subtended 4.3.deg. vertically and horizontally. Density, meridian and subject showed a significant effect on stationary field at .alpha.=0.01, where density was inversely proportional to the size of stationary field. The size of the stationary field on horizontal axis was larger than that on vertical axis, and that on right and below meridian also larger than on left and lower meridian. The shape was found to be horizontally oriented oval and statistically asymmetric with respect to horizontal and vertical axes. The regression equation to predict stationary field on the given background condition was suggested. These results were expected to be used as a designing guideline when arranging displays and controls on panels such as automobile display panels, cockpits, etc. In addition, it can be inferred from the results that eye field and head field are also subjected to the influence of background condition.

• Journal of Electrical Engineering and information Science
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• 제2권6호
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• pp.106-110
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• 1997

The binding energies of the ground state of both the heavy-hole and light-hole excitons in a GaAs(In\ulcornerGa\ulcornerAs) quantum well sandwiched between two semi-infinite Al\ulcornerGa\ulcornerAs(InP) layers are calculated as a function of well width in the presence of an arbitray magnetic field. A variational approach is followed using very simple trial wave function. The applied magnetic field is assumed to be parallel to the axis of growth and the binding energies are calculated for a finite value of the height of the potential barrier. The exciton binding energies for a given value of the magnetic field are found to be increased than their values in a zero magnetic field due to the compression of their wave functions within the well with the applied magnetic field.

• 한국해양공학회지
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• 제25권2호
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• pp.55-61
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• 2011

A field trial in an ice-covered sea is one of the most important tasks in the design of icebreaking ships and offshore structures. To correctly estimate the ice load and ice resistance of a ship's hull, it is essential to understand the material properties of sea ice during ice field trials and to use the proper experimental procedure for gathering effective ice data. The first Korean-made icebreaking research vessel, "ARAON," had her second sea ice trial in the Arctic Ocean during the summer season of 2010. This paper describes the test procedures used to obtain proper sea ice data, which provides the basic information for the ship's performance in an ice-covered sea and is used to estimate the correct ice load and ice resistance of the IBRV ARAON. The data gathered from the sea ice in the Chukchi Sea and Beaufort Sea during the Arctic voyage of the ARAON includes the temperature, density, and salinity of the sea ice, which was believed to be from two-year old ice floes. This paper analyses the gathered sea ice data in comparison with data from the first voyage of the ARAON during her Antarctic Sea ice trial.