• Title/Summary/Keyword: 고정효과 모형

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Employee's Business Outlook Disclosed Through Social Media And Employment Growth : The Case of Jobplanet (소셜미디어를 통한 직원의 기업전망 평가와 고용증가와의 상관성 : 잡플래닛 기업전망을 대상으로)

  • Byeongsoo, Kim;Ju Young, Kang
    • Smart Media Journal
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    • v.11 no.10
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    • pp.9-21
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    • 2022
  • The recent expansion of the use of social media has served as an opportunity to express users' opinions in real time in various fields such as society, economy, politics, and culture, and brought many platforms that provide various information about companies. Among them, Glassdoor.com which started 2008 in US provides users with evaluations of the current and the former employees of their companies and also provides a outlooks for the company's growth Such a platform has the utility of providing necessary information to whom want to find a job or change jobs. In addition to this, variable studies have shown that the company information provided through these platforms is useful for investors as well. In this study, it was tested whether the corporate growth prospects of employees provided by Jobplanet, a platform with a typical function similar to Glassdoor.com in Korea, have predictive power to predict actual corporate growth. The forecast provided by Jobplanet and the company's financial indicator data received from FnGuide were collected and composed of panel data and analyzed using fixed effect model regression analysis. As a result, it was found that companies with positive prospects had higher employment growth than companies with negative prospects. When the outlook was neutral, the employment growth rate was higher than that of companies with a negative outlook.

The Point Load Index of the Daegu Shale and its Relation to the Uniaxial Compressive Strength (대구지역 셰일의 점재하지수 특성 및 일축압축강도와의 상관성)

  • Lee, Younghuy;Youn, Chanho
    • Journal of the Korean GEO-environmental Society
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    • v.10 no.3
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    • pp.37-45
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    • 2009
  • The experimental study was carried out to evaluate the characteristics of the point load index and the uniaxial compressive strength of inherently anisotropic shale in the laboratory. In the testing program the effects of size and the shape on the point load index were investigated both in the axial and diametral direction. In general, the point load index of the shale was constant when the length/diameter (L/D) ratio of the specimen is greater than 1.0 in the diametral direction. The point load index in axial direction shows slight decrease as the L/D ratio is increased and the corner breakage was observed when L/D ratio is greater than unity. The minimum point load index was observed in the bedding angle of $\beta=15^{\circ}{\sim}30^{\circ}$ in the axial point load tests and of $\beta=30^{\circ}$ in the uniaxial compression tests. The relationship between the point load index and the uniaxial compressive strength was linear to ${\sigma}_c=25.0 I_{s(50)}$ for the specimen with the bedding plane angle, $\beta$ at the range of $0^{\circ}{\sim}90^{\circ}$. On the other hand, this relationship was appeared linear to ${\sigma}_c=14.4 I_{s(50)}$ when the bedding angle, $\beta$ is fixed to 90${^{\circ}}$ and this correlation is much different from ${\sigma}c=22 I_{s(50)}, which is generally applied to the rock specimen with no bedding plane in ISRM (1985). The anisotropic strength with different $\beta$ angle shows the shoulder type and this can be suitably modelled by the corrected Ramamurthy'(1993)s equation with the index value of 'n' equal to 3.0.

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A study of the economic effects of weather and climate information on marine logistics (해상운송업의 기상기후정보 경제적 효과에 관한 연구)

  • Lho, Sangwhan;Lim, Dongsoon
    • Environmental and Resource Economics Review
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    • v.23 no.1
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    • pp.1-19
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    • 2014
  • Weather seems to influence industries in a variety of ways. On a day-to-day basis, it is the most volatile external factor influencing consumer and market behavior. And, because weather is constantly changing, industries must deal with a continuously shifting array of opportunities and risks. This study aims to examine how climate and weather changes and information, as external environmental factors, have affected the Korean industries, particularly marine shipping and logistics. To find out the economic value of marine weather information, we use measurable results of VVOS(Vessel and Voyage Optimization Services) in the ocean shipping, which the marine weather software tool can save fuel costs up to 4%. When the fuel saving is same as VVOS's performance, the saving of Korean flag ship is estimated about 62 billion won and the saving of total flag ship is estimated about 519 billion won. However, coastal shipping companies have been struggling with the heavy weather factors, such as wave height, wave period and wind. Major findings are that wind and wave height have a significant negative effect on cargo transport, while wave period has a significant positive effect on cargo transport. And to conclude, when we use efficiently the marine weather information, we can increase cargo transport and save fuel costs etc.

The Influence of Export Promotion Programs on SMEs' Export Performance: Focusing on Promising SMEs in Export (수출유망중소기업 지원프로그램이 수출성과에 미치는 영향에 관한 연구)

  • Jaekyung Ko;Chulhyung Park;Chang-Yong Han
    • Journal of Korea Society of Industrial Information Systems
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    • v.28 no.2
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    • pp.95-107
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    • 2023
  • The purpose of this study is to investigate the impact of export promotion programs (EPPs) on the export performance of small- and medium-sized enterprises (SMEs), with a specific focus on the influence of EPPs for promising SMEs in the export market. Using data on SMEs provided by the Industrial Bank of Korea (IBK), we conducted a fixed-effects model analysis from 2016 to 2019. Our study shows that EPPs have a positive and significant relationship with export intensity. Further analysis reveals that SMEs utilizing the financing support system provided by EPPs tend to improve their export growth and financial performance relative to their counterparts. While EPPs can assist SMEs with their internationalization efforts, their similarity and redundancy are recognized as potential limitations. This study complements the existing literature that has mainly focused on surveys and cross-sectional analysis by specifying the research subject to promising SMEs in export, and analyzing the effects of the export promotion program supported by IBK Industrial Bank. The results of this study are expected to provide implications for improving SMEs' export capabilities.

Estimation of Family Variation and Genetic Parameter for Growth Traits of Pacific Abalone, Haliotis discus hannai on the 3th Generation of Selection (선발 3세대 북방전복의 성장형질에 대한 가계변이 및 유전모수 추정)

  • Park, Jong-Won;Park, Choul-Ji;Lee, Jeong-Ho;Noh, Jae-Koo;Kim, Hyun-Chul;Hwang, In-Joon;Kim, Sung-Yeon
    • The Korean Journal of Malacology
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    • v.29 no.4
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    • pp.325-334
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    • 2013
  • The purpose of this paper is to compare and analyze family variations for growth-related traits of Pacific abalone, Haliotis discus hannai. Genetic parameters and breeding values were estimated using all measurement data like shell length, shell width, and total weight as 18-month-old growth traits of 5,334 individuals of selected third generation's Pacific abalone produced in 2011. Family variations of 865 individuals of the upper 10 families with the largest number were inspected. Overall mean in phenotypic traits of 18-month-old Pacific abalone which was investigated in this study showed 54.5 mm of shell length, 36.8 mm of shell width and 21.3 g of total weight respectively. And, variation coefficient of total weight was 51.0%, so variability of data was shown to be higher than 21.1% of shell length and 20.7% of shell width. The family effects showed significant difference by each family (p < 0.05), and heritability of shell length, shell width, and total weight was medium with 0.370, 0.382, and 0.367 respectively. So it is considered that family selection is more advantageous than individual selection. On the basis of breeding values of estimated shell length and total weight, to investigate distribution and ranking by each individual about the upper 10 families with the largest number of individuals, the values were used by being changed into standardized breeding values. Based on shell length, it was investigated that the individual number of the upper 5.4% is 152 and the number of the lower 5.4% is 8. In case of total weight, it was inspected that the individual number of the upper 5.4% is 164 and the number of the lower 5.4% is 1. Like these, phenotypic and genetic diverse variations between families could be checked. By estimating genetic parameters and breeding values of a population for production of the next generation, if they are used properly in selection and mating, it is considered that more breeding effects can be expected.

Studies on Effects of Channel Bed Fixation by Erosion Control Dams in Torrential Streams (황폐계류(荒廢溪流)에 있어서 사방시설물(砂防施設物)에 의한 하도고정(河道固定)에 관한 연구(硏究))

  • Chun, Kun Woo
    • Journal of Korean Society of Forest Science
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    • v.79 no.3
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    • pp.269-277
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    • 1990
  • In planning the disaster prevention by the erosion control facilities, it is essential to focus on the microtopography of the channel bed and the chronological process of sedimental movement in the torrential streams. For this purpose, the microtopographical change of the channel bed and the effects of the erosion control facilities in the mountain torrents were analyzed by the experimental channel and the field survey of the torrents where low-dam series had been constructed in the channel. The results of this experiment showed that the effects of construction of the low-dam series on the channel bed fixiation were the prevention of the local scouring in the experimental channel and the expansion of flow channel width and deposit space. The results are summarized as follows : 1. When the low-dam series were constructed over the whole channel bed (L'/L=1), the conning water and the sediment were seperated, simultaneously resulting in deposition of sediment and reduction of the tractive force for the running water. Therefore, the F.A. (Fluctuation area in cross-section: value was decreased to about 65% compared with that of non-work (L'/L=0). 2. The efficiencies of the low-dam series on the channel width were increased with an increment in length of working space. After the construction of low-dam series on the whole channel bed (L'/L=1), flow channel width was increased to about 1.53 times compared with that of non-work (L'/L=0). 3. It needs a deposition area to store the sediment with decrease in tractive force. The low-dam series in the experimental channel widened the deposition area about 2.10 times compared with that of non-work.

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Factors Influencing on Total Fertility Rate using Panel Analysis (패널분석을 이용한 합계출산율에 영향을 미치는 요인분석)

  • Choi, Eun-Hee;Cho, Taek-Hee
    • The Journal of the Korea Contents Association
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    • v.16 no.8
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    • pp.59-70
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    • 2016
  • This study aimed to find effective policies to cope with low birth rate in local authorities. It was analyzed the variables-a number of child-care facilities, paid parental leave, labor force participation, and total working hours-using panel analysis from 2005 to 2014. The results were as follows. First, after testing the whole years, we found that the fittest model was the fixed-effects model of 2 models(fixed-effects model, random effects model). A number of child-care facilities had positive effects, and a number of child-care facilities, and total working hours in women influenced negative effects on total fertility rate. Second, during the former time and the period of plan for low birth rate and aging society, a number of child-care facilities influenced negative effects on total fertility rate. Third, a number of child-care facilities had negative effects on total fertility rate in Busan, Daegu, and Kwangju. Paid parental leave influenced positively on total fertility rate in 5 cities and a province. Women's total working hours were a significant variable of total fertility rate in Jeju. This study found that the variables which influenced on total fertility rate were different by local authorities, and a number of child-care facilities and paid parental leave were very important variables on total fertility rate.

Optimization of Osmotic Dehydration Process for Manufacturing a Dried Sweet Pumpkin (건조단호박 제조를 위한 삼투건조공정의 최적화)

  • 나경민;홍주헌;차원섭;박준희;오상룡;조영제;이원영
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.2
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    • pp.433-438
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    • 2004
  • This study was conducted to develop a sweet pumpkin to intermediate materials for various processed foods and dried food having high quality. Factorial experiment design with three variables having three levels was adapted and response surface methodology was used to determine optimum conditions for osmotic dehydration of sweet pumpkin. The moisture content, weight reduction, moisture loss and solid gain after osmotic dehydration increased according to increasement of immersion temperature, concentration and time. The effect of concentration was more significant than that of temperature and time at given conditions. Sugar concentration and vitamin C content increased in accordance with increasement of immersion temperature, concentration and time during osmotic dehydration. Hardness was increased by increasing immersion time. The regression models showed very significant values and high correlation coefficients (R2) above 0.91, excepting hardness. The optimum condition for osmotic dehydration was 23$^{\circ}C$, 52$^{\circ}C$Brix and 80 min at the constricted conditions such as 60∼70% moisture content, above 3 mg/100 g vitamin C and more than 10 kg/$\textrm{cm}^2$ hardness.

Emprical Tests of Braess Paradox (The Case of Namsan 2nd Tunnel Shutdown) (브라이스역설에 대한 실증적 검증 (남산2호터널 폐쇄사례를 중심으로))

  • 엄진기;황기연;김익기
    • Journal of Korean Society of Transportation
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    • v.17 no.3
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    • pp.61-70
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    • 1999
  • The Purpose of this study is to test whether Braess Paradox (BP) can be revealed in a real world network. Fer the study, Namsan 2nd tunnel case is chosen, which was shut down for 3 years for repair works. The revelation of BP is determined by analyzing network-wise traffic impacts followed by the tunnel closure. The analysis is conducted using a network simulation model called SECOMM developed for the congestion management of the Seoul metropolitan area. Also, the existence of BP is further identified by a before-after traffic survey result of the major arterials nearby the Namsan 2nd tunnel. The model estimation expected that the closure of Namsan 2nd tunnel improve the network-wise average traffic speed from 21.95km/h to 22.21km/h when the travel demand in the study area and congestion Pricing scheme on Namsan 1st & 3rd tunnels remain unchanged. In addition, the real world monitoring results of the corridors surrounding Namsan 2nd tunnel show that the average speed increases from 29.53km/h to 30.37km/h after the closure. These findings clearly identify the BP Phenomenon is revealed in this case.

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Uplift Bearing Capacity of Spiral Steel Peg for the Single Span Greenhouse (온실용 나선철항의 인발저항력 검토)

  • Lee, Bong Guk;Yun, Sung Wook;Choi, Man Kwon;Lee, Si Young;Moon, Sung Dong;Yu, Chan;Yoon, Yong Cheol
    • Journal of Bio-Environment Control
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    • v.23 no.2
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    • pp.109-115
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    • 2014
  • This study examined the uplift bearing capacity of spiral steel pegs according to the degree of soil compaction and embedded depth in a small-scaled lab test. As a result, their uplift bearing capacity increased according to the degree of soil compaction and embedded depth. The uplift bearing capacity under the ground condition of 85% compaction rate especially recorded 48.9 kgf, 57.9 kgf, 86.2 kgf and 116.6 kgf at embedded depth of 25 cm, 30 cm, 35 cm and 40 cm, respectively, being considerably higher than under other ground conditions. There were huge differences in the uplift bearing capacity of spiral steel pegs according to the compaction conditions of ground. Their maximum uplift bearing capacity was 116.6 kgf under the ground condition of 85% compaction rate and at embedded depth of 40 cm, and it is very high considering the data of spiral steel pegs. It is thus estimated that wind damage can be effectively reduced by careful maintenance of ground condition surrounding spiral steel pegs. In addition, spiral steel pegs will be able to make a contribution to greenhouse structural stability if proper installation methods are provided including the number and interval according to the types of greenhouse as well as fixation of plastic film. The findings of the study indicate that the optimal effects of spiral steel pegs for greenhouse can be achieved at embedded depth of more than 35cm and compaction degree of more than 85%. The relative density of the model ground in the test was 67% at compaction rate of 85%.