• The Journal of Fisheries Business Administration
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• v.18 no.1
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• pp.37-57
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• 1987

This article discussed the characteristics of several Pareto-optimal incentive contracts between owner and labor, more specifically, four situations: reporting output jointly observable by labor ana owner; reporting both output and effort; incorporating other endogenous elements (like capital) that affect the production process and Pareto-optimal fee schedules; and ascertaining the effects of private pre-decision information private- decision information, and per-contact informational asymmetries. Also presented were several extensions of the basic contractual model, and the different components of agency costs associated with labor-owner contractual relations. In a single-period model, the agency problem exists because the uncertainty prevents the owner from using the cash flow to determine unambiguously the labor's action. Holmstrom(1979) suggests that "when the same situation repeats itself over time, the effects of uncertainty tend to be reduced and dystunctional behavior is more accurately revealed, thus alleviating the problem of moral hazard. " Under these conditions, if the labor selects the first-best level of effect in each period, the cash flow will be independent and identically distributed over time. As the number of periods increases, the variance of the labows average output, if he selects the first-best level of effort in each period, gets smaller. Note that for this diversification effect to occur, it is necessary that the owner evaluate the labor's effort over the entire history of his employment, rather than evaluate each period's performance separately. Radner(1980) and Rubinstein and Yaari(1980) consider the extreme case in which there are an infinite number of observations. They show that the owner can eventually detect and systematic shirking on the part of the labor by comparing the labor's average output with what would be expected if the labor had been selecting the first-best level of effort in each period. In a dynamic model with incentive problems we have demonstrated that the labor's second-period compensation will depend on his first-period performance. This allows the owner to diversify away some of the uncertainty surrounding the labor's actions. In addition, this allows the owner to smooth the labor's income over time by spreading the risk of the first-period outcome over both periods. At least some unexplored avenves in this area invite future accounting research: situations where owner has different incompatible objectives and negotiates a contract with labor; circumstances in which owner deals with multiple objectives and negotiates contracts with several labors simultaneously; the value of costly accounting information systems and communication in establishing, Pareto-optimal incentive contracts, and the value and effects of inside information, Thorough theoretical or empirical research on each of these topics not only would increase our knowledge about the role and significance of accounting information but could also provide explanations of the inherent differences among various organizations and in their economic behavior. behavior.

• The Journal of Korean Academy of Prosthodontics
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• v.32 no.1
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• pp.148-169
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• 1994

The concept of biologic attachment of load-bearing implants has developed over the past decades as an alternative to the difficulties associated with long term implantation using mechanical fixation and bone cement. The choice of implant material is also as critical an element as site preparation or insertion procedure. The properties of implants that affect host tissue responses are not limited to chemical composition alone, but also include shape, surface characteristics, site of implantation, and mechanical interaction with host tissues. Initial mechanical interlocking prevents micromotion and may be a prerequisite for direct bone apposition. A hard tightening of screws does not necessarily mean a stronger fixation and final tightening of the fixtures is dependent on the experience of the operator. Removal torque is lower than insertion torque. The purpose of this study was to investigate differences in the removal torques at the bone-implant interface of polished and sandblasted Titanium. This experiment will give insight into important factors that must be considered when interpreting in vivo screwing forces on implants during the connection of the transmucosal abutments. We evaluated the significance of different surface textures by comparison of the withdrawal forces necessary for removal of otherwise identical rough and polished implants of Titanium and also evaluated interfacial response on the light microscopic level to implant surface. And the priority of the area of insertion on osseointegration were evaluated. 9 Titanium implants - among them, 3 were for the developmental - of either a smooth or rough surface finish were inserted in the dog mandible in the right side. 3 months later Kanon Torque Gauge was used to unscrew the implants. The results were as follows : 1. No significant difference was seen in the removal torque due to variation in surface treatment, 23 Ncm for the sandblasted and 23.33 Ncm for the polished surface (p>0.05). 2. Implants in the anterior (25 Ncm) mandible showed better resistance to unscrewing in comparison to ones in the posterior (18 Ncm) region (p<0.05). 3. Developmental fixtures (22 Ncm) had similar pullout strength to the control group (p>0.05).

• Tuberculosis and Respiratory Diseases
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• v.52 no.4
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• pp.411-418
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• 2002

Pulmonary alveolar proteinosis(PAP) is a disorder in which an insoluble, proteinaceous material, rich in phospholipids, is deposited in the alveoli and bronchioles. The deficiency in the clearance and degradation of the intra-alveolar phospholipoproteinaceous material in PAP most likely represents a dysfunction of the type II pneumocytes. Although the pathogenesis and causative treatment of PAP is unclear a whole lung bronchopulmonary lavage is a relatively safe and effective treatment. Here we experienced a case of pulmonary alveolar proteinosis in a 62 year old female patient who had pulmonary tuberculosis approximately 20 years ago. She complained of aggravated dyspnea and chronic cough, and presented fine inspiratory crackles at both lung fields, diffuse ground glass opacity with some area of consolidation and smooth interlobular septal thickenings in both upper, right middled lobes, and a portion of right lower lobe. Optical microscopy of the lung tissue obtained by and open lung biopsy revealed many granulomas containing acid-fast smear positive bacilli and diffuse homogeneous PAS-positive fluid in the alveolar space. Immunohistochemical stain showed surfactant. A in the alveolar space. Antituberculosis drugs with bronchoalveolar lavage were used to treat the disease. Thereafter she showed improvement in her symptoms and a partial improvement in the chest X-ray and HRCT findings. We present a case of PAP associated with pulmonary tuberculosis.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.7
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• pp.591-598
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• 2015

Pool boiling heat transfer coefficients of a LiBr solution were obtained for seven low fin tubes having different fin pitch and fin height. The test range covered saturation pressure from 7.38kPa to 101.3kPa, heat flux from $20kW/m^2$ to $40 kW/m^2$ and LiBr concentration from 0% to 50%. The optimum fin geometry for the present experimental range turned out to be 26 fpi with 0.18 mm fin height.The advantage of added heat transfer area and the disadvantage of slower bubble growth and departure appear to have yielded an optimum fin pitch. The heat transfer coefficient decreased as saturation pressure decreased and Libr concentration increased. The reason may be attributed to the low saturation pressure, which increased the bubble departure diameter and decreased the bubble departure frequency. As the LiBr concenreation increased, the saturation temperature increased and the mass diffusion rate decreased, which resulted in a reduced heat transfer coefficient. The heat transfer coefficients of the low fin tube were greater than those of the smooth tube. Correlations were developed based on the present data.

• Journal of Korean Ophthalmic Optics Society
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• v.21 no.3
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• pp.159-171
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• 2016

Purpose: This study investigated medical accessibility on optical stores and ophthalmic clinics of Seoul Special City and six other metropolitan cities. Methods: By using a number of households, population, optician stores, ophthalmic hospitals, and real estate (apartments) standard market price of Seoul Special City and six other metropolitan cities provided by the Commercial District Information System (2016.6) of Small Enterprise & Market Authority, we analyzed the level of healthcare accessibility and business area zones, Statistical analyses were performed with SPSS 18.0. Results: Inchon (household 2,227/population 5,723) had the highest household and population rate per optical store, and Gwangju (1,146/2,979) had the lowest. Gwangju (24,612/63,987) had the highest household and population rate per optical store, and Seoul (10,021/24,432) had the lowest. From the consumer and patient's point of view, lower household rate per optical store is a city with good accessibility to healthcare, but from an optical store and ophthalmic clinic's view, it will have great difficulty due to issues of competition. Conclusions: Consumers and patients should be the center of healthcare. A healthcare system that can provide smooth service anywhere anytime should be constructed. However, most metropolitan cities, including Seoul, have optical stores and ophthalmic clinics densely populated where profitability and liquidity are ensured and causing unbalanced distribution of healthcare. To solve such problems, we need proper distribution of optician stores according to the population proportion and industrial-educational research to find balance point of local healthcare.

• Journal of IKEEE
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• v.24 no.2
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• pp.638-648
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• 2020

Currently, the method of user-follwoing in intelligent cooperative robots usually based in vision system and using Lidar is common and have excellent performance. But in the closed space of Corona 19, which spread worldwide in 2020, robots for cooperation with medical staff were insignificant. This is because Medical staff are all wearing protective clothing to prevent virus infection, which is not easy to apply with existing research techniques. Therefore, in order to solve these problems in this paper, the ultrasonic sensor is separated from the transmitting and receiving parts, and based on this, this paper propose that estimating the user's position and can actively follow and cooperate with people. However, the ultrasonic sensors were partially applied by improving the Median filter in order to reduce the error caused by the short circuit in communication between hard reflection and the number of light reflections, and the operation technology was improved by applying the curvature trajectory for smooth operation in a small area. Median filter reduced the error of degree and distance by 70%, vehicle running stability was verified through the training course such as 'S' and '8' in the result.

• Journal of Broadcast Engineering
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• v.25 no.4
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• pp.497-506
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• 2020

A chameleonic surface proposed in this study was a pin-art and 3D display device for generating arbitrary shapes. A smooth and continuous surface was formed using slim telescopic actuators and high-elasticity composite material. Realistic 3D shapes were continuously generated by projecting dynamic mapping images on the surface. A slim telescopic actuator was designed to show long strokes and minimize area for staking. A 3D shape was formed by thrusting and extruding the high-elasticity material using multiple telescopic actuators. This structure was advantageous for generating arbitrary continuous surface, projecting dynamic images and lightening weight. Because of real-time synchronization, a distributed controller based on EtherCAT was applied to operate hundreds of telescopic actuators smoothly. Integrated operating software consecutively generated realistic scenes by coordinating extruded shapes and projecting 3D image from multiple projectors. An opera content was optimized for the chameleon surface and showed to an audience in an actual concert.

• The Journal of the Korea Contents Association
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• v.13 no.11
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• pp.957-967
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• 2013

While a vast number of cad drawings are produced in the life cycle of construction projects from the planning, design, and construction phases to the maintenance and control phases, the creation and distribution of non-standard drawings make it difficult for the construction parties to communicate with one another and to recycle, maintain, and control drawings by project phase. The Korea standard of CAD drawing in construction CALS/EC, which stipulates the standard for construction CAD drawings, is based on roads, rivers, and railways in line- and unit-based structures, allowing the creation of standardized CAD drawings. Such standard, however, cannot be easily applied to construction projects with multiple facilities like harbors, housing sites, or lands consisting of surface forms. In particular, port field consist of complex docks and amenities located in a certain coastal area based on multiple objectives. They also contain the concept of housing sites, like background land, and are composed of various civil engineering facilities, construction facilities, and port field, so that the existing CAD drawing standard cannot be easily implemented. Therefore, the purpose of this study is to maximize the efficiency of the information related to drawing information and to ultimately support smooth information exchanges in construction design by conducting a development research on the expansion of the CAD drawing standard that meets the needs of port field.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.15 no.3
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• pp.157-170
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• 1993

To prove the effct of semi-rigid fixation which utilize wire and rigid fixation which utilizes miniplate toward cranio-facial growth and development of growing children for teenagers, 28 rabbits-6 weeks, about 1.5kg-were experimented. They were classified three groups the semi-rigid group was 12 rabbits which were fixed with 26 gauge stainless steel wire to cross a fronto-nasal suture, the rigid group was the other 12 rabbits which were fixed with miniplate and screw, the control group was 4 rabbits which were get rid of only periosteum. The sample of fronto-nasal of rabbits which were sacrified after 2 weeks, 4 weeks, 8 weeks, and 12 weeks of the operation were investigated and made a comparative study with the light microscops. 1. At the control group, the central part of bony suture was connected with colagen bundle, the osteoblastic layer was investigated at the bony ending, new bone which covered the inside and outside faces of the bone suture was formed between periosteum. 2. Two weeks later from the experiment, ran slightly irregularly the collagen bundle which connects both bony endings of the rigid group. 3. Four weeks later from the experiment, collagen bundle of bone surface were arranged parally a little and comparing to the semi-rigid group, newly formed woven bone of surface of the adjacent bone was made obviously a little. 4. Eight weeks later from the experiment, collagen bundle which is located between both bony ending become close. Both the semi-rigid group and the rigid group showed significant formation of new bone at the periosteum and the bone surface. 12 weeks later from the experiment, both the semi-rigid group and the rigid group showed the regular running in the collagen bundle and smooth, dense periosteum. Then they assumed a similar aspect of the control group. I think that it does not give the influence to the cranio-facial growth of children or teenager to utilize a rigid fixation for a short period. Because as the time goes on, the surface of the bone suture was recovered and adjacent bone surface of the miniplate fixation showed compensatory growth, although both the semi-rigid group which utilized wire and rigid group which utilized a miniplate brought about the change of the area of the bone suture at the early period.

• Journal of Broadcast Engineering
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• v.16 no.2
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• pp.274-292
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• 2011

This paper proposes an efficient coding method of the depth-map which is different from the natural images. The depth-map are so smooth in both inner parts of the objects and background, but it has sharp edges on the object-boundaries like a cliff. In addition, when a depth-map block is decomposed into bit planes, the characteristic of perfect matching or inverted matching between bit planes often occurs on the object-boundaries. Therefore, the proposed depth-map coding scheme is designed to have the bit-plane unit coding method using the adaptive XOR method for efficiently coding the depth-map images on the object-boundary areas, as well as the conventional DCT-based coding scheme (for example, H.264/AVC) for efficiently coding the inside area images of the objects or the background depth-map images. The experimental results show that the proposed algorithm improves the average bit-rate savings as 11.8 % ~ 20.8% and the average PSNR (Peak Signal-to-Noise Ratio) gains as 0.9 dB ~ 1.5 dB in comparison with the H.264/AVC coding scheme. And the proposed algorithm improves the average bit-rate savings as 7.7 % ~ 12.2 % and the average PSNR gains as 0.5 dB ~ 0.8 dB in comparison with the adaptive block-based depth-map coding scheme. It can be confirmed that the proposed method improves the subjective quality of synthesized image using the decoded depth-map in comparison with the H.264/AVC coding scheme. And the subjective quality of the proposed method was similar to the subjective quality of the adaptive block-based depth-map coding scheme.