• Title/Summary/Keyword: immersion time

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A Study on Manipulating Method of 3D Game in HMD Environment by using Eye Tracking (HMD(Head Mounted Display)에서 시선 추적을 통한 3차원 게임 조작 방법 연구)

  • Park, Kang-Ryoung;Lee, Eui-Chul
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.45 no.2
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    • pp.49-64
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    • 2008
  • Recently, many researches about making more comfortable input device based on gaze detection technology have been done in human computer interface. However, the system cost becomes high due to the complicated hardware and there is difficulty to use the gaze detection system due to the complicated user calibration procedure. In this paper, we propose a new gaze detection method based on the 2D analysis and a simple user calibration. Our method used a small USB (Universal Serial Bus) camera attached on a HMD (Head-Mounted Display), hot-mirror and IR (Infra-Red) light illuminator. Because the HMD is moved according to user's facial movement, we can implement the gaze detection system of which performance is not affected by facial movement. In addition, we apply our gaze detection system to 3D first person shooting game. From that, the gaze direction of game character is controlled by our gaze detection method and it can target the enemy character and shoot, which can increase the immersion and interest of game. Experimental results showed that the game and gaze detection system could be operated at real-time speed in one desktop computer and we could obtain the gaze detection accuracy of 0.88 degrees. In addition, we could know our gaze detection technology could replace the conventional mouse in the 3D first person shooting game.

Effects of Thyroid Hormones on Settlement, Survival and Growth in Olive Flounder, Paralichthys olivaceus Larvae (Thyroid hormone 처리에 의한 넙치, Paralichthys olivaceus 자어의 착저, 생존 및 성장)

  • Bang In Chul;Kim Yoon;Kim Kyung-Kil;Kim Dong Soo
    • Journal of Aquaculture
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    • v.8 no.2
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    • pp.133-140
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    • 1995
  • Olive flounder (Paralichthys olivaceus) larvae of pre-metamorphic and early metamorphic stage were treated with different concentrations of triiodothyroxine $(T_3)\;and\; thyroxine\;(T_4)$ by immersion (0.02, 0.04, 0.08 and 0.16 ppm) for 11 days. Although $T_3$ was more potent than $T_4,\;both\;T_3\;and\;T_4$ accelerated the settlement time of fish larvae. Duration upto complete settlement in hormone-treated groups was significantly shorter than that in controls. Survival of hormone-treated groups at the pre-metamorphic stage decreased as hormone concentrations increased, however groups treated at the early metamorphic stage were not differ from control. Growth rates of groups treated with high concentration of hormone were slightly lower than that of control except 0.02ppm $T_4$ treated group.

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Study on the Estimation of Long Life Cycle and Reliability Tests for Epoxy Insulation Busway System (에폭시 박막 절연형 버스웨이 시스템의 장기 수명 및 신뢰성 평가에 관한 연구)

  • Jang, Dong-Uk;Park, Seong-Hee;Lee, Kang-Won
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.9
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    • pp.261-268
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    • 2018
  • The use of electric cable was limited due to the installation time and large space as the increase of power demand and load quantity in side line. In order to solve these problems, the application of busway system which can supply the large current was increasing. But it was lack of methods of performance tests to evaluate the reliability and results of test for busway system. In this paper, we presented items to evaluate the reliability test for epoxy coated busway system with reference to IEC 61349-6. In addition, we proposed items to evaluate the reliability and long term life cycle test for the epoxy coated busway system. The combined acceleration deterioration test that reflects actual conditions of the survey as much as possible was conducted considering both thermal and electrical stresses. The deterioration condition was selected to satisfy fifty years life expectation and the insulation performance verification test of the busway system confirmed the long term life prediction. Furthermore, as test items for reliability assessment of compliance with the environment for the use of temperature, humidity and load current where busway system was installed, thermal overload test, water immersion test, cold shock temperature test and thermal cycle test were performed. And we examined changes in characteristics and abnormality after tests. From results, the test items presented to evaluate performance and reliability of the epoxy insulated busway system were confirmed to be appropriate in this paper, and the performance of the product was also confirmed to be excellent for reliability tests.

Inclusion effect of soybean meal, fermented soybean meal, and Saccharina japonica in extruded pellet for juvenile abalone (Haliotis discus, Reeve 1846)

  • Yun, Ahyeong;Kim, June;Jeong, Hae Seung;Lee, Ki Wook;Kim, Hee Sung;Kim, Pil Youn;Cho, Sung Hwoan
    • Fisheries and Aquatic Sciences
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    • v.21 no.9
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    • pp.26.1-26.8
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    • 2018
  • Inclusion effect of soybean meal (SBM) and fermented SBM (FSM) in extruded pellet for juvenile abalone (Haliotis discus) was compared in abalone farm. Dietary inclusion effect of the combined macroalgae (MA) (Undaria pinnatifida and Hizikia fusiforme) and a single Saccharina japonica on abalone was also compared. Three thousand six hundred juvenile abalone were purchased from a private hatchery and acclimated to the experimental conditions for 2 weeks. Six 5-ton flow-through raceway tanks were used, and abalone were randomly distributed into tanks (n = 600 per tank). Three experimental diets were prepared in duplicate. Fish meal, FSM, corn gluten meal, and shrimp meal and wheat flour and dextrin were used as the protein and carbohydrate sources, respectively, in the FSM diet. MA was also included in the FSM diet. FSM and MA in the FSM diet were substituted with SBM at the expense of wheat flour and S. japonica, referred to as the SBM and SJ diets. The experimental diets were pelletized by an extruded pelleter. Water stability of nutrients in the experimental diets was monitored at 12, 24, and 48 h after seawater immersion. The experimental diets were fed to abalone once a day to satiation with a little leftover for 120 days. The retained crude protein and lipid and ash content of the extruded pellets were changed over all period of time. Weight gain and specific growth rate (SGR) of abalone fed the SBM diet were greater than those of abalone fed the FSM and SJ diets. Weight gain and SGR of abalone fed the SJ diet were also greater than those of abalone fed the FSM diet. The longest shell length, widest shell width, highest shell height, and greatest soft body weight were obtained in abalone fed the SBM diet, followed by the SJ and FSM diets. Proximates of the soft body of abalone were not different among the experimental diets. In conclusion, SBM was a superior protein source to FSM in extruded pellet for growth performance of abalone. Dietary inclusion of a single S. japonica was superior to the combined inclusion of U. pinnatifida and H. fusiforme in the production of abalone.

Changes of Internal Pressure during Freezing, Frozen Storage and Thawing of Meats (식육의 동결, 냉동냉장 및 해동시 내부압력 변화)

  • Jeong, Jin-Woong;Kim, Jong-Hoon
    • Korean Journal of Food Science and Technology
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    • v.31 no.3
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    • pp.682-687
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    • 1999
  • The destruction of tissues by volume increase at food freezing is accepted as one of the factor responsible for quality damage. For this reason, the internal pressure developed in meats were investigated with a pressure transducer during freezing, frozen storage and thawing. Increasement of 6.33% for volume and $942.17\;kg/cm^2$ for density at $-20^{\circ}C$ for beef were shown. In quick and slow freezing of beef, internal pressure reached to highest point after reached to the lowest point at initial of the zone of ice crystal formation. The internal pressure was approximately $8{\sim}10\;psig$ and pressure difference was about 1 psig, which was bigger in immersion freezing than that of still-air freezing. During frozen storage of pork, internal pressure of $1.84{\sim}2.32\;psig$ occurred repeatedly as a function of sample weight at material temperature difference of ${\pm}1^{\circ}C$. The internal pressure during thawing of pork was decreased slowly after rapid increase to the maximum for less than 5min at the beginning of thawing. Internal pressure value at thawing was higher than that at freezing in most cases. Internal pressure of beef with thermal equalized freezing was about $1{\sim}4\;psig$, which was lower than that of non-thermal equalized freezing. Also, freezing time was shortened to $10{\sim}20%$.

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Changes in Quality during Frozen Storage of Meat with Thermal Equalized Freezing (균온처리 동결에 의한 식육의 저장중 품질변화)

  • Jeong, Jin-Woong;Lee, Ho-Jun;Park, Noh-Hyun
    • Korean Journal of Food Science and Technology
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    • v.31 no.3
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    • pp.688-696
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    • 1999
  • Changes in quality during frozen storage of meat with thermal equalized freezing and various freezing methods were investigated. When beef were frozen at freezing rate of $0.39{\sim}0.66\;cm/h$, average diameter of ice crystal were about $30{\sim}50\;{\mu}m$ and showed broken tissues or irregular cracks. At freezing velocity of $1.14{\sim}2.26\;cm/h$, ice crystals of about $10{\sim}30\;{\mu}m$ was formed mainly inside or between fiber and slight destruction of tissues was occurred. The average diameter (D) of the ice crystals were related to the characteristic freezing time $(t_c)$ by the equation: $D({\mu}m)=4.089+26.88logt_c\;(r^2=0.913)$. Beef with still-air freezing showed higher drip loss than methods of immersion and thermal equalized freezing. Also, drip loss of pork was relatively lower than beef and showed highest value to 7.39% during storage on 40 days at air-blast freezing method. No apparent change of pH during storage of frozen beef and pork by freezing methods were detected. However, least changes for sample with thermal equalized freezing was found compare to sample with still-air and air blast freezing in VBN and TBA value. The fluctuation of frozen storage temperature did not cause noticeable changes on pH and water content. However, drip loss, VBN and TBA values were increased slowly as frequency of fluctuation increased.

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The Efficacy of Biofeedback in Reducing Cybersickness in Virtual Navigation (생체신호 피드백을 적용한 가상 주행환경에서 사이버멀미 감소 효과)

  • 김영윤;김은남;정찬용;고희동;김현택
    • Science of Emotion and Sensibility
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    • v.5 no.2
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    • pp.29-34
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    • 2002
  • Our previous studies investigated that narrow field of view (FOV : 50˚) and slow navigation speed decreased the frequency of occurrence and severity of cybersickness during immersion in the virtual reality (VR). It would cause a significant reduction of cybersickness if it were provided cybersickness alleviating virtual environment (CAVE) using biofeedback method whenever subject underwent physiological agitation. For verifying the hypothesis, we constructed a real-time cybersickness detection and feedback system with artificial neural network whose inputs are electrophysiological parameters of blood pulse volume, skin conductance, eye blink, skin temperature, heart period, and EEG. The system temporary provided narrow FOV and decreased speed of navigation as feedback outputs whenever physiological measures signal the occurrence of cybersickness. We examined the frequency and severity of cybersickness from simulator sickness questionnaires and self-report in 36 subjects. All subjects experienced VR two times in CAVE and non-CAVE condition at one-month intervals. The frequency and severity of cybersickness were significantly reduced in CAVE than non-CAVE condition. Virtual environment of narrow FOV and slow navigation provided by electrophysiological features based artificial neural network caused a significant reduction of cybersickness symptoms. These results showed that efficiency of a cybersickness detection system we developed was relatively high and subjects expressed more comfortable in the virtual navigation environment.

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Evaluation of Properties of Artificial Soil Aggregate Based on Ground Granulated Blast-Furnace Slag According to Unit Binder Content (단위결합재량에 따른 고로슬래그 기반 육성용 인공토양골재의 특성평가)

  • Mun, Ju-Hyun;Sim, Jae-Il;Yun, In-Gu
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.20 no.5
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    • pp.85-92
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    • 2016
  • The eight mixes and artificial soil aggregates were prepared for evaluating the practical application of lightweight foamed concrete as soil aggregates. The main parameter was unit binder content ranged between from 100 to $800kg/m^3$. In lightweight foamed concrete, flow, slurry and dried density, and compressive strength at different ages were measured. In Artificial soil aggregates crushed from lightweight foamed concrete, particle size distribution, pH, coefficient of permeability, cation exchange capacity(CEC), and ratio of carbon to nitrogen(ratio of C/N), were measured. The test results showed that flow, slurry and dried density, and compressive strength at different ages of lightweight foamed concrete increased with the increasing of unit binder content. Compressive strength at age of 28, of lightweight foamed concrete with unit binder of more than $500kg/m^3$, was more than 4 MPa. The ammonium phosphate immersion time of more than age of 3, was effective to decrease pH of artificial soil aggregates. In addition, artificial soil aggregates was evaluated as high class in terms of cation exchange capacity(CEC), while satisfied with value of ratio of carbon to nitrogen(ratio of C/N) recommended by landscape specification.

Interface of Interactive Contents using Vision-based Body Gesture Recognition (비전 기반 신체 제스처 인식을 이용한 상호작용 콘텐츠 인터페이스)

  • Park, Jae Wan;Song, Dae Hyun;Lee, Chil Woo
    • Smart Media Journal
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    • v.1 no.2
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    • pp.40-46
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    • 2012
  • In this paper, we describe interactive contents which is used the result of the inputted interface recognizing vision-based body gesture. Because the content uses the imp which is the common culture as the subject in Asia, we can enjoy it with culture familiarity. And also since the player can use their own gesture to fight with the imp in the game, they are naturally absorbed in the game. And the users can choose the multiple endings of the contents in the end of the scenario. In the part of the gesture recognition, KINECT is used to obtain the three-dimensional coordinates of each joint of the limb to capture the static pose of the actions. The vision-based 3D human pose recognition technology is used to method for convey human gesture in HCI(Human-Computer Interaction). 2D pose model based recognition method recognizes simple 2D human pose in particular environment On the other hand, 3D pose model which describes 3D human body skeletal structure can recognize more complex 3D pose than 2D pose model in because it can use joint angle and shape information of body part Because gestures can be presented through sequential static poses, we recognize the gestures which are configured poses by using HMM In this paper, we describe the interactive content which is used as input interface by using gesture recognition result. So, we can control the contents using only user's gestures naturally. And we intended to improve the immersion and the interest by using the imp who is used real-time interaction with user.

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Substitution effect of white radish (Raphanus sativus L.)' by-product and tunic of sea squirt (Halocynthia rorentzi, von Drasche) for Undaria pinnatifida in feed of abalone (Haliotis discus, Reeve 1846)

  • Lee, Ki Wook;Kim, Hee Sung;Kim, Pil Youn;Jeong, Hae Seung;Kim, June;Yun, Ah-Yeong;Cho, Sung Hwoan
    • Fisheries and Aquatic Sciences
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    • v.21 no.4
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    • pp.10.1-10.8
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    • 2018
  • Substitution effect of white radish' by-product (WRB) and tunic of sea squirt (TSS) for Undaria in feed on growth and carcass composition of abalone was determined. Eight-hundred forty juveniles were distributed into 12 containers. Three formulated diets were prepared in triplicate. A 15% Undaria was included in the control diet. The 15% Undaria was substituted with a same amount of WRB and TSS, referred to as the DRG and TSS diets, respectively. Finally, dry Undaria was also prepared to compare effect of the formulated diets on performance of abalone. The experimental diets were fed to abalone once a day at a satiation level with a little leftover. The feeding trial lasted for 16 weeks. Crude protein, crude lipid, and ash content of the experimental diets changed over all period of time. Higher crude protein and lipid and ash contents retained in all formulated diets compared to the Undaria were observed at 24 and 48 h after seawater immersion. Survival of abalone was not affected by the experimental diets. Weight gain and specific growth rate (SGR) of abalone fed the TSS diet was greater than all other diets. Weight gain and SGR of abalone fed the control diet was not different from those of abalone fed the WRB diet. Proximates of the soft body of abalone was affected by the diets. In conclusion, WRB and TSS are the promising feed ingredients to replace Undaria in abalone feed; especially, TSS is superior to either Undaria or WRB. The formulated diets produced improved growth performance of abalone over the single Undaria.